Release v0.1.7

.gitignore

@@ -8,3 +8,270 @@ __pycache__/
 node_modules/
 dist/
 webui/dist/
+
+# GovOPlaN shared ignore rules from govoplan-core
+# ---> Node
+# Logs
+logs
+*.log
+npm-debug.log*
+yarn-debug.log*
+yarn-error.log*
+lerna-debug.log*
+.pnpm-debug.log*
+# Diagnostic reports (https://nodejs.org/api/report.html)
+report.[0-9]*.[0-9]*.[0-9]*.[0-9]*.json
+# Runtime data
+pids
+*.pid
+*.seed
+*.pid.lock
+# Directory for instrumented libs generated by jscoverage/JSCover
+lib-cov
+# Coverage directory used by tools like istanbul
+coverage
+*.lcov
+# nyc test coverage
+.nyc_output
+# Grunt intermediate storage (https://gruntjs.com/creating-plugins#storing-task-files)
+.grunt
+# Bower dependency directory (https://bower.io/)
+bower_components
+# node-waf configuration
+.lock-wscript
+# Compiled binary addons (https://nodejs.org/api/addons.html)
+build/Release
+# Dependency directories
+jspm_packages/
+# Snowpack dependency directory (https://snowpack.dev/)
+web_modules/
+# TypeScript cache
+*.tsbuildinfo
+# Optional npm cache directory
+.npm
+# Optional eslint cache
+.eslintcache
+# Optional stylelint cache
+.stylelintcache
+# Microbundle cache
+.rpt2_cache/
+.rts2_cache_cjs/
+.rts2_cache_es/
+.rts2_cache_umd/
+# Optional REPL history
+.node_repl_history
+# Output of 'npm pack'
+*.tgz
+# Yarn Integrity file
+.yarn-integrity
+# dotenv environment variable files
+.env
+.env.development.local
+.env.test.local
+.env.production.local
+.env.local
+# parcel-bundler cache (https://parceljs.org/)
+.cache
+.parcel-cache
+# Next.js build output
+.next
+out
+# Nuxt.js build / generate output
+.nuxt
+dist
+# Gatsby files
+.cache/
+# Comment in the public line in if your project uses Gatsby and not Next.js
+# https://nextjs.org/blog/next-9-1#public-directory-support
+# public
+# vuepress build output
+.vuepress/dist
+# vuepress v2.x temp and cache directory
+.temp
+.cache
+# vitepress build output
+**/.vitepress/dist
+# vitepress cache directory
+**/.vitepress/cache
+# Docusaurus cache and generated files
+.docusaurus
+# Serverless directories
+.serverless/
+# FuseBox cache
+.fusebox/
+# DynamoDB Local files
+.dynamodb/
+# TernJS port file
+.tern-port
+# Stores VSCode versions used for testing VSCode extensions
+.vscode-test
+# yarn v2
+.yarn/cache
+.yarn/unplugged
+.yarn/build-state.yml
+.yarn/install-state.gz
+.pnp.*
+# Local WebUI test/build scratch directories
+.component-test-build/
+.module-test-build/
+.policy-test-build/
+.template-preview-test-build/
+.import-test-build/
+webui/.component-test-build/
+webui/.module-test-build/
+webui/.policy-test-build/
+webui/.template-preview-test-build/
+webui/.import-test-build/
+# ---> Python
+# Byte-compiled / optimized / DLL files
+*$py.class
+# C extensions
+*.so
+# Distribution / packaging
+.Python
+build/
+develop-eggs/
+downloads/
+eggs/
+.eggs/
+lib/
+lib64/
+parts/
+sdist/
+var/
+wheels/
+share/python-wheels/
+.installed.cfg
+*.egg
+MANIFEST
+# PyInstaller
+#  Usually these files are written by a python script from a template
+#  before PyInstaller builds the exe, so as to inject date/other infos into it.
+*.manifest
+*.spec
+# Installer logs
+pip-log.txt
+pip-delete-this-directory.txt
+# Unit test / coverage reports
+htmlcov/
+.tox/
+.nox/
+.coverage
+.coverage.*
+.cache
+nosetests.xml
+coverage.xml
+*.cover
+*.py,cover
+.hypothesis/
+cover/
+# Translations
+*.mo
+*.pot
+# Django stuff:
+*.log
+local_settings.py
+db.sqlite3
+db.sqlite3-journal
+# Flask stuff:
+instance/
+.webassets-cache
+# Scrapy stuff:
+.scrapy
+# Sphinx documentation
+docs/_build/
+# PyBuilder
+.pybuilder/
+target/
+# Jupyter Notebook
+.ipynb_checkpoints
+# IPython
+profile_default/
+ipython_config.py
+# pyenv
+#   For a library or package, you might want to ignore these files since the code is
+#   intended to run in multiple environments; otherwise, check them in:
+# .python-version
+# pipenv
+#   According to pypa/pipenv#598, it is recommended to include Pipfile.lock in version control.
+#   However, in case of collaboration, if having platform-specific dependencies or dependencies
+#   having no cross-platform support, pipenv may install dependencies that don't work, or not
+#   install all needed dependencies.
+#Pipfile.lock
+# UV
+#   Similar to Pipfile.lock, it is generally recommended to include uv.lock in version control.
+#   This is especially recommended for binary packages to ensure reproducibility, and is more
+#   commonly ignored for libraries.
+#uv.lock
+# poetry
+#   Similar to Pipfile.lock, it is generally recommended to include poetry.lock in version control.
+#   This is especially recommended for binary packages to ensure reproducibility, and is more
+#   commonly ignored for libraries.
+#   https://python-poetry.org/docs/basic-usage/#commit-your-poetrylock-file-to-version-control
+#poetry.lock
+# pdm
+#   Similar to Pipfile.lock, it is generally recommended to include pdm.lock in version control.
+#pdm.lock
+#   pdm stores project-wide configurations in .pdm.toml, but it is recommended to not include it
+#   in version control.
+#   https://pdm.fming.dev/latest/usage/project/#working-with-version-control
+.pdm.toml
+.pdm-python
+.pdm-build/
+# PEP 582; used by e.g. github.com/David-OConnor/pyflow and github.com/pdm-project/pdm
+__pypackages__/
+# Celery stuff
+celerybeat-schedule
+celerybeat.pid
+# SageMath parsed files
+*.sage.py
+# Environments
+.env
+.venv
+env/
+venv/
+ENV/
+env.bak/
+venv.bak/
+# Spyder project settings
+.spyderproject
+.spyproject
+# Rope project settings
+.ropeproject
+# mkdocs documentation
+/site
+# mypy
+.dmypy.json
+dmypy.json
+# Pyre type checker
+.pyre/
+# pytype static type analyzer
+.pytype/
+# Cython debug symbols
+cython_debug/
+# PyCharm
+#  JetBrains specific template is maintained in a separate JetBrains.gitignore that can
+#  be found at https://github.com/github/gitignore/blob/main/Global/JetBrains.gitignore
+#  and can be added to the global gitignore or merged into this file.  For a more nuclear
+#  option (not recommended) you can uncomment the following to ignore the entire idea folder.
+#.idea/
+# Ruff stuff:
+# PyPI configuration file
+.pypirc
+# ---> VisualStudioCode
+.vscode/*
+!.vscode/settings.json
+!.vscode/tasks.json
+!.vscode/launch.json
+!.vscode/extensions.json
+!.vscode/*.code-snippets
+# Local History for Visual Studio Code
+.history/
+# Built Visual Studio Code Extensions
+*.vsix
+*.db
+# GovOPlaN local runtime state
+runtime/
+# GovOPlaN WebUI test output
+webui/.module-test-build/
+webui/.component-test-build/

package.json

@@ -1,6 +1,6 @@
 {
   "name": "@govoplan/calendar-webui",
-  "version": "0.1.5",
+  "version": "0.1.7",
   "private": true,
   "type": "module",
   "main": "webui/src/index.ts",
@@ -19,8 +19,8 @@
     "LICENSE"
   ],
   "peerDependencies": {
-    "@govoplan/core-webui": "^0.1.5",
+    "@govoplan/core-webui": "^0.1.7",
-    "lucide-react": "^0.555.0",
+    "lucide-react": "^1.23.0",
     "react": "^19.0.0",
     "react-dom": "^19.0.0",
     "react-router-dom": "^7.1.1",

pyproject.toml

@@ -4,15 +4,15 @@ build-backend = "setuptools.build_meta"
 
 [project]
 name = "govoplan-calendar"
-version = "0.1.5"
+version = "0.1.7"
 description = "GovOPlaN calendar module with VEVENT storage and WebUI integration."
 readme = "README.md"
 requires-python = ">=3.12"
 license = { file = "LICENSE" }
 authors = [{ name = "GovOPlaN" }]
 dependencies = [
-  "govoplan-core>=0.1.5",
+  "govoplan-core>=0.1.7",
-  "govoplan-access>=0.1.5",
+  "govoplan-access>=0.1.7",
   "icalendar>=7.2",
   "python-dateutil>=2.9",
 ]

src/govoplan_calendar/backend/caldav.py

@@ -21,6 +21,10 @@ class CalDAVPreconditionFailed(CalDAVError):
     pass
 
 
+class CalDAVNotFound(CalDAVError):
+    pass
+
+
 class CalDAVTransport(Protocol):
     def __call__(self, method: str, url: str, headers: Mapping[str, str], body: bytes | None, timeout: int) -> tuple[int, Mapping[str, str], bytes]:
         ...
@@ -48,6 +52,29 @@ class CalDAVWriteResult:
     status: int = 0
 
 
+@dataclass(frozen=True, slots=True)
+class CalDAVDiscoveryCalendar:
+    collection_url: str
+    href: str
+    display_name: str | None = None
+    color: str | None = None
+    ctag: str | None = None
+    sync_token: str | None = None
+
+
+@dataclass(frozen=True, slots=True)
+class _DAVDiscoveryResponse:
+    href: str
+    display_name: str | None = None
+    color: str | None = None
+    ctag: str | None = None
+    sync_token: str | None = None
+    is_calendar: bool = False
+    principal_hrefs: tuple[str, ...] = ()
+    calendar_home_set_hrefs: tuple[str, ...] = ()
+    supported_components: tuple[str, ...] = ()
+
+
 class CalDAVClient:
     def __init__(
         self,
@@ -78,6 +105,96 @@ class CalDAVClient:
         payload = self.request("PROPFIND", self.collection_url, body=body, depth="0", expected={207})
         return parse_multistatus(payload)
 
+    def discover_calendars(self) -> list[CalDAVDiscoveryCalendar]:
+        start_url = self.collection_url
+        calendars: dict[str, CalDAVDiscoveryCalendar] = {}
+        home_urls: list[str] = []
+        principal_urls: list[str] = []
+        visited_urls: set[tuple[str, str]] = set()
+        errors: list[str] = []
+
+        def add_home_href(base_url: str, href: str) -> None:
+            url = ensure_collection_url(absolute_dav_url(base_url, href))
+            if url not in home_urls:
+                home_urls.append(url)
+
+        def add_principal_href(base_url: str, href: str) -> None:
+            url = ensure_collection_url(absolute_dav_url(base_url, href))
+            if url not in principal_urls:
+                principal_urls.append(url)
+
+        def add_calendar(base_url: str, response: _DAVDiscoveryResponse) -> None:
+            if not response.is_calendar:
+                return
+            if response.supported_components and "VEVENT" not in response.supported_components:
+                return
+            url = ensure_collection_url(absolute_dav_url(base_url, response.href or base_url))
+            calendars[url] = CalDAVDiscoveryCalendar(
+                collection_url=url,
+                href=response.href,
+                display_name=response.display_name,
+                color=response.color,
+                ctag=response.ctag,
+                sync_token=response.sync_token,
+            )
+
+        def propfind(url: str, depth: str) -> list[_DAVDiscoveryResponse]:
+            key = (url, depth)
+            if key in visited_urls:
+                return []
+            visited_urls.add(key)
+            return self.propfind_discovery(url, depth=depth)
+
+        try:
+            for response in propfind(start_url, "0"):
+                add_calendar(start_url, response)
+                for href in response.calendar_home_set_hrefs:
+                    add_home_href(start_url, href)
+                for href in response.principal_hrefs:
+                    add_principal_href(start_url, href)
+        except CalDAVError as exc:
+            errors.append(str(exc))
+
+        for principal_url in principal_urls[:6]:
+            try:
+                for response in propfind(principal_url, "0"):
+                    for href in response.calendar_home_set_hrefs:
+                        add_home_href(principal_url, href)
+            except CalDAVError as exc:
+                errors.append(str(exc))
+
+        if not home_urls:
+            home_urls.append(start_url)
+
+        for home_url in home_urls:
+            try:
+                for response in propfind(home_url, "1"):
+                    add_calendar(home_url, response)
+            except CalDAVError as exc:
+                errors.append(str(exc))
+
+        if not calendars and errors:
+            raise CalDAVError(f"CalDAV discovery did not find any calendar collections: {errors[0]}")
+        return sorted(calendars.values(), key=lambda item: ((item.display_name or item.collection_url).lower(), item.collection_url))
+
+    def propfind_discovery(self, url: str, *, depth: str) -> list[_DAVDiscoveryResponse]:
+        body = b"""<?xml version="1.0" encoding="utf-8"?>
+<D:propfind xmlns:D="DAV:" xmlns:C="urn:ietf:params:xml:ns:caldav" xmlns:CS="http://calendarserver.org/ns/" xmlns:ICAL="http://apple.com/ns/ical/">
+  <D:prop>
+    <D:displayname/>
+    <D:current-user-principal/>
+    <D:principal-URL/>
+    <D:resourcetype/>
+    <D:sync-token/>
+    <C:calendar-home-set/>
+    <C:supported-calendar-component-set/>
+    <CS:getctag/>
+    <ICAL:calendar-color/>
+  </D:prop>
+</D:propfind>"""
+        payload = self.request("PROPFIND", ensure_collection_url(url), body=body, depth=depth, expected={207})
+        return parse_discovery_multistatus(payload)
+
     def list_objects(self) -> CalDAVReportResult:
         body = b"""<?xml version="1.0" encoding="utf-8"?>
 <C:calendar-query xmlns:D="DAV:" xmlns:C="urn:ietf:params:xml:ns:caldav">
@@ -182,6 +299,8 @@ class CalDAVClient:
             headers.update(dict(extra_headers))
         status, response_headers, payload = self.transport(method, url, headers, body, self.timeout)
         if status not in expected:
+            if status == 404:
+                raise CalDAVNotFound(f"{method} {url} returned HTTP {status}")
             if status == 412:
                 raise CalDAVPreconditionFailed(f"{method} {url} failed because the remote resource changed")
             raise CalDAVError(f"{method} {url} returned HTTP {status}")
@@ -189,14 +308,16 @@ class CalDAVClient:
 
 
 def urllib_transport(method: str, url: str, headers: Mapping[str, str], body: bytes | None, timeout: int) -> tuple[int, Mapping[str, str], bytes]:
-    request = urllib.request.Request(url, data=body, headers=dict(headers), method=method)
     try:
+        request = urllib.request.Request(url, data=body, headers=dict(headers), method=method)
         with urllib.request.urlopen(request, timeout=timeout) as response:
             return response.status, dict(response.headers.items()), response.read()
     except urllib.error.HTTPError as exc:
         return exc.code, dict(exc.headers.items()), exc.read()
     except urllib.error.URLError as exc:
         raise CalDAVError(f"{method} {url} failed: {exc.reason}") from exc
+    except ValueError as exc:
+        raise CalDAVError(f"{method} {url} failed: {exc}") from exc
 
 
 def parse_multistatus(payload: bytes) -> CalDAVReportResult:
@@ -232,10 +353,80 @@ def parse_multistatus(payload: bytes) -> CalDAVReportResult:
     return CalDAVReportResult(objects=objects, sync_token=sync_token, ctag=ctag)
 
 
+def parse_discovery_multistatus(payload: bytes) -> list[_DAVDiscoveryResponse]:
+    try:
+        root = ElementTree.fromstring(payload)
+    except ElementTree.ParseError as exc:
+        raise CalDAVError(f"Invalid CalDAV XML response: {exc}") from exc
+    responses: list[_DAVDiscoveryResponse] = []
+    for response in child_elements(root, "response"):
+        href = first_child_text(response, "href")
+        if not href:
+            continue
+        display_name = None
+        color = None
+        ctag = None
+        sync_token = None
+        is_calendar = False
+        principal_hrefs: list[str] = []
+        calendar_home_set_hrefs: list[str] = []
+        supported_components: list[str] = []
+        for propstat in child_elements(response, "propstat"):
+            status = first_child_text(propstat, "status") or ""
+            if status and " 200 " not in status and not status.endswith(" 200") and " 207 " not in status:
+                continue
+            prop = first_child(propstat, "prop")
+            if prop is None:
+                continue
+            for item in prop:
+                name = local_name(item.tag)
+                if name == "displayname" and item.text:
+                    display_name = item.text.strip() or display_name
+                elif name == "calendar-color" and item.text:
+                    color = item.text.strip() or color
+                elif name == "getctag" and item.text:
+                    ctag = item.text.strip() or ctag
+                elif name == "sync-token" and item.text:
+                    sync_token = item.text.strip() or sync_token
+                elif name == "resourcetype":
+                    is_calendar = is_calendar or any(local_name(child.tag) == "calendar" for child in item)
+                elif name in {"current-user-principal", "principal-URL"}:
+                    principal_hrefs.extend(nested_href_texts(item))
+                elif name == "calendar-home-set":
+                    calendar_home_set_hrefs.extend(nested_href_texts(item))
+                elif name == "supported-calendar-component-set":
+                    for component in item:
+                        if local_name(component.tag) == "comp":
+                            component_name = (component.attrib.get("name") or "").strip().upper()
+                            if component_name:
+                                supported_components.append(component_name)
+        responses.append(
+            _DAVDiscoveryResponse(
+                href=href,
+                display_name=display_name,
+                color=color,
+                ctag=ctag,
+                sync_token=sync_token,
+                is_calendar=is_calendar,
+                principal_hrefs=tuple(dict.fromkeys(principal_hrefs)),
+                calendar_home_set_hrefs=tuple(dict.fromkeys(calendar_home_set_hrefs)),
+                supported_components=tuple(dict.fromkeys(supported_components)),
+            )
+        )
+    return responses
+
+
 def ensure_collection_url(value: str) -> str:
+    value = value.strip()
+    if value and "://" not in value and not value.startswith("/"):
+        value = f"https://{value}"
     return value if value.endswith("/") else f"{value}/"
 
 
+def absolute_dav_url(base_url: str, href: str) -> str:
+    return urllib.parse.urljoin(ensure_collection_url(base_url), href)
+
+
 def strip_weak_etag(value: str | None) -> str | None:
     if value is None:
         return None
@@ -271,5 +462,13 @@ def child_elements(element: ElementTree.Element, name: str) -> list[ElementTree.
     return [child for child in element if local_name(child.tag) == name]
 
 
+def nested_href_texts(element: ElementTree.Element) -> list[str]:
+    hrefs: list[str] = []
+    for child in element.iter():
+        if local_name(child.tag) == "href" and child.text and child.text.strip():
+            hrefs.append(child.text.strip())
+    return hrefs
+
+
 def local_name(tag: str) -> str:
     return tag.rsplit("}", 1)[-1] if "}" in tag else tag

src/govoplan_calendar/backend/db/models.py

@@ -29,7 +29,7 @@ class CalendarCollection(Base, TimestampMixin):
     )
 
     id: Mapped[str] = mapped_column(String(36), primary_key=True, default=new_uuid)
-    tenant_id: Mapped[str] = mapped_column(ForeignKey("tenants.id", ondelete="CASCADE"), nullable=False, index=True)
+    tenant_id: Mapped[str] = mapped_column(String(36), nullable=False, index=True)
     slug: Mapped[str] = mapped_column(String(100), nullable=False)
     name: Mapped[str] = mapped_column(String(255), nullable=False)
     description: Mapped[str | None] = mapped_column(Text)
@@ -39,7 +39,7 @@ class CalendarCollection(Base, TimestampMixin):
     owner_id: Mapped[str | None] = mapped_column(String(36), nullable=True, index=True)
     visibility: Mapped[str] = mapped_column(String(20), default="tenant", nullable=False, index=True)
     is_default: Mapped[bool] = mapped_column(Boolean, default=False, nullable=False, index=True)
-    created_by_user_id: Mapped[str | None] = mapped_column(ForeignKey("users.id", ondelete="SET NULL"), nullable=True, index=True)
+    created_by_user_id: Mapped[str | None] = mapped_column(ForeignKey("access_users.id", ondelete="SET NULL"), nullable=True, index=True)
     deleted_at: Mapped[datetime | None] = mapped_column(DateTime(timezone=True), nullable=True, index=True)
     metadata_: Mapped[dict[str, Any] | None] = mapped_column("metadata", JSON, nullable=True)
 
@@ -56,7 +56,7 @@ class CalendarEvent(Base, TimestampMixin):
     )
 
     id: Mapped[str] = mapped_column(String(36), primary_key=True, default=new_uuid)
-    tenant_id: Mapped[str] = mapped_column(ForeignKey("tenants.id", ondelete="CASCADE"), nullable=False, index=True)
+    tenant_id: Mapped[str] = mapped_column(String(36), nullable=False, index=True)
     calendar_id: Mapped[str] = mapped_column(ForeignKey("calendar_collections.id", ondelete="CASCADE"), nullable=False, index=True)
     uid: Mapped[str] = mapped_column(String(255), nullable=False, index=True)
     recurrence_id: Mapped[str | None] = mapped_column(String(255), nullable=True, index=True)
@@ -86,8 +86,8 @@ class CalendarEvent(Base, TimestampMixin):
     etag: Mapped[str | None] = mapped_column(String(255), index=True)
     icalendar: Mapped[dict[str, Any]] = mapped_column(JSON, default=dict, nullable=False)
     raw_ics: Mapped[str | None] = mapped_column(Text)
-    created_by_user_id: Mapped[str | None] = mapped_column(ForeignKey("users.id", ondelete="SET NULL"), nullable=True, index=True)
+    created_by_user_id: Mapped[str | None] = mapped_column(ForeignKey("access_users.id", ondelete="SET NULL"), nullable=True, index=True)
-    updated_by_user_id: Mapped[str | None] = mapped_column(ForeignKey("users.id", ondelete="SET NULL"), nullable=True, index=True)
+    updated_by_user_id: Mapped[str | None] = mapped_column(ForeignKey("access_users.id", ondelete="SET NULL"), nullable=True, index=True)
     deleted_at: Mapped[datetime | None] = mapped_column(DateTime(timezone=True), nullable=True, index=True)
     metadata_: Mapped[dict[str, Any] | None] = mapped_column("metadata", JSON, nullable=True)
 
@@ -110,7 +110,7 @@ class CalendarSyncSource(Base, TimestampMixin):
     )
 
     id: Mapped[str] = mapped_column(String(36), primary_key=True, default=new_uuid)
-    tenant_id: Mapped[str] = mapped_column(ForeignKey("tenants.id", ondelete="CASCADE"), nullable=False, index=True)
+    tenant_id: Mapped[str] = mapped_column(String(36), nullable=False, index=True)
     calendar_id: Mapped[str] = mapped_column(ForeignKey("calendar_collections.id", ondelete="CASCADE"), nullable=False, index=True)
     source_kind: Mapped[str] = mapped_column(String(30), default="caldav", nullable=False, index=True)
     collection_url: Mapped[str] = mapped_column(String(1000), nullable=False)
@@ -142,11 +142,11 @@ class CalendarSyncCredential(Base, TimestampMixin):
     )
 
     id: Mapped[str] = mapped_column(String(36), primary_key=True, default=new_uuid)
-    tenant_id: Mapped[str] = mapped_column(ForeignKey("tenants.id", ondelete="CASCADE"), nullable=False, index=True)
+    tenant_id: Mapped[str] = mapped_column(String(36), nullable=False, index=True)
     credential_kind: Mapped[str] = mapped_column(String(30), nullable=False, index=True)
     label: Mapped[str | None] = mapped_column(String(255))
     secret_encrypted: Mapped[str | None] = mapped_column(Text)
-    created_by_user_id: Mapped[str | None] = mapped_column(ForeignKey("users.id", ondelete="SET NULL"), nullable=True, index=True)
+    created_by_user_id: Mapped[str | None] = mapped_column(ForeignKey("access_users.id", ondelete="SET NULL"), nullable=True, index=True)
     deleted_at: Mapped[datetime | None] = mapped_column(DateTime(timezone=True), nullable=True, index=True)
     metadata_: Mapped[dict[str, Any] | None] = mapped_column("metadata", JSON, nullable=True)
 

src/govoplan_calendar/backend/ical.py

@@ -92,6 +92,8 @@ def parse_vevent_component(calendar: Calendar, event: Event, *, raw_ics: str) ->
     properties = component_property_records(event)
     alarms = [component_alarm_record(alarm) for alarm in event.subcomponents if alarm.name == "VALARM"]
     standard = standard_property_index(properties)
+    if dtend is None and duration_seconds is not None:
+        standard["uses_duration"] = True
 
     return {
         "uid": uid,
@@ -154,7 +156,9 @@ def event_to_component(event: Any) -> Event:
     component.add("uid", event.uid)
     component.add("dtstamp", datetime.now(timezone.utc))
     component.add("dtstart", event_temporal_value(event.start_at, all_day=event.all_day, timezone_id=event.timezone))
-    if event.end_at is not None:
+    if event_uses_duration(event):
+        component.add("duration", timedelta(seconds=int(event.duration_seconds)))
+    elif event.end_at is not None:
         component.add("dtend", event_temporal_value(event.end_at, all_day=event.all_day, timezone_id=event.timezone))
     elif getattr(event, "duration_seconds", None) is not None:
         component.add("duration", timedelta(seconds=int(event.duration_seconds)))
@@ -474,6 +478,16 @@ def metadata_value(event: Any, key: str) -> str | None:
     return str(value) if value else None
 
 
+def event_uses_duration(event: Any) -> bool:
+    if getattr(event, "duration_seconds", None) is None:
+        return False
+    raw_metadata = getattr(event, "icalendar", None)
+    if not isinstance(raw_metadata, dict):
+        return False
+    standard = raw_metadata.get("standard")
+    return isinstance(standard, dict) and standard.get("uses_duration") is True
+
+
 def event_temporal_value(value: datetime, *, all_day: bool, timezone_id: str | None) -> date | datetime:
     value = normalize_datetime(value)
     if all_day:

src/govoplan_calendar/backend/manifest.py

@@ -3,6 +3,7 @@ from __future__ import annotations
 from pathlib import Path
 
 from govoplan_calendar.backend.db import models as calendar_models  # noqa: F401 - populate Calendar ORM metadata
+from govoplan_core.core.access import CAPABILITY_AUTH_PERMISSION_EVALUATOR, CAPABILITY_AUTH_PRINCIPAL_RESOLVER
 from govoplan_core.core.module_guards import drop_table_retirement_provider, persistent_table_uninstall_guard
 from govoplan_core.core.modules import FrontendModule, MigrationSpec, ModuleContext, ModuleManifest, NavItem, PermissionDefinition, RoleTemplate
 from govoplan_core.db.base import Base
@@ -87,8 +88,8 @@ def _calendar_router(context: ModuleContext):
 manifest = ModuleManifest(
     id="calendar",
     name="Calendar",
-    version="0.1.5",
+    version="0.1.7",
-    dependencies=("access",),
+    required_capabilities=(CAPABILITY_AUTH_PRINCIPAL_RESOLVER, CAPABILITY_AUTH_PERMISSION_EVALUATOR),
     optional_dependencies=("mail", "tasks", "scheduling", "appointments", "workflow", "notifications", "dms", "connectors"),
     permissions=PERMISSIONS,
     route_factory=_calendar_router,

src/govoplan_calendar/backend/migrations/versions/7c8d9e0f1a2b_calendar_collections_events.py

@@ -1,7 +1,7 @@
 """calendar collections and VEVENT storage
 
 Revision ID: 7c8d9e0f1a2b
-Revises: 1b2c3d4e5f70
+Revises: 2e3f4a5b6c7d
 Create Date: 2026-07-07 00:00:00.000000
 """
 from __future__ import annotations
@@ -11,14 +11,19 @@ import sqlalchemy as sa
 
 
 revision = "7c8d9e0f1a2b"
-down_revision = "1b2c3d4e5f70"
+down_revision = "2e3f4a5b6c7d"
 branch_labels = None
 depends_on = None
 
 
+def _scope_fk_target(tables: set[str]) -> str:
+    return "core_scopes.id" if "core_scopes" in tables else "tenancy_tenants.id"
+
+
 def upgrade() -> None:
     inspector = sa.inspect(op.get_bind())
     tables = set(inspector.get_table_names())
+    scope_fk_target = _scope_fk_target(tables)
     if "calendar_collections" not in tables:
         op.create_table(
             "calendar_collections",
@@ -38,8 +43,8 @@ def upgrade() -> None:
             sa.Column("metadata", sa.JSON(), nullable=True),
             sa.Column("created_at", sa.DateTime(timezone=True), nullable=False),
             sa.Column("updated_at", sa.DateTime(timezone=True), nullable=False),
-            sa.ForeignKeyConstraint(["created_by_user_id"], ["users.id"], name=op.f("fk_calendar_collections_created_by_user_id_users"), ondelete="SET NULL"),
+            sa.ForeignKeyConstraint(["created_by_user_id"], ["access_users.id"], name=op.f("fk_calendar_collections_created_by_user_id_users"), ondelete="SET NULL"),
-            sa.ForeignKeyConstraint(["tenant_id"], ["tenants.id"], name=op.f("fk_calendar_collections_tenant_id_tenants"), ondelete="CASCADE"),
+            sa.ForeignKeyConstraint(["tenant_id"], [scope_fk_target], name=op.f("fk_calendar_collections_tenant_id_scopes"), ondelete="CASCADE"),
             sa.PrimaryKeyConstraint("id", name=op.f("pk_calendar_collections")),
         )
         op.create_index(op.f("ix_calendar_collections_tenant_id"), "calendar_collections", ["tenant_id"], unique=False)
@@ -100,9 +105,9 @@ def upgrade() -> None:
             sa.Column("created_at", sa.DateTime(timezone=True), nullable=False),
             sa.Column("updated_at", sa.DateTime(timezone=True), nullable=False),
             sa.ForeignKeyConstraint(["calendar_id"], ["calendar_collections.id"], name=op.f("fk_calendar_events_calendar_id_calendar_collections"), ondelete="CASCADE"),
-            sa.ForeignKeyConstraint(["created_by_user_id"], ["users.id"], name=op.f("fk_calendar_events_created_by_user_id_users"), ondelete="SET NULL"),
+            sa.ForeignKeyConstraint(["created_by_user_id"], ["access_users.id"], name=op.f("fk_calendar_events_created_by_user_id_users"), ondelete="SET NULL"),
-            sa.ForeignKeyConstraint(["tenant_id"], ["tenants.id"], name=op.f("fk_calendar_events_tenant_id_tenants"), ondelete="CASCADE"),
+            sa.ForeignKeyConstraint(["tenant_id"], [scope_fk_target], name=op.f("fk_calendar_events_tenant_id_scopes"), ondelete="CASCADE"),
-            sa.ForeignKeyConstraint(["updated_by_user_id"], ["users.id"], name=op.f("fk_calendar_events_updated_by_user_id_users"), ondelete="SET NULL"),
+            sa.ForeignKeyConstraint(["updated_by_user_id"], ["access_users.id"], name=op.f("fk_calendar_events_updated_by_user_id_users"), ondelete="SET NULL"),
             sa.PrimaryKeyConstraint("id", name=op.f("pk_calendar_events")),
             sa.UniqueConstraint("calendar_id", "uid", "recurrence_id", name="uq_calendar_events_calendar_uid_recurrence"),
         )

src/govoplan_calendar/backend/migrations/versions/8d9e0f1a2b3c_caldav_sync_sources.py

@@ -16,11 +16,16 @@ branch_labels = None
 depends_on = None
 
 
+def _scope_fk_target(tables: set[str]) -> str:
+    return "core_scopes.id" if "core_scopes" in tables else "tenancy_tenants.id"
+
+
 def upgrade() -> None:
     inspector = sa.inspect(op.get_bind())
     tables = set(inspector.get_table_names())
     if "calendar_sync_sources" in tables:
         return
+    scope_fk_target = _scope_fk_target(tables)
     op.create_table(
         "calendar_sync_sources",
         sa.Column("id", sa.String(length=36), nullable=False),
@@ -42,7 +47,7 @@ def upgrade() -> None:
         sa.Column("created_at", sa.DateTime(timezone=True), nullable=False),
         sa.Column("updated_at", sa.DateTime(timezone=True), nullable=False),
         sa.ForeignKeyConstraint(["calendar_id"], ["calendar_collections.id"], name=op.f("fk_calendar_sync_sources_calendar_id_calendar_collections"), ondelete="CASCADE"),
-        sa.ForeignKeyConstraint(["tenant_id"], ["tenants.id"], name=op.f("fk_calendar_sync_sources_tenant_id_tenants"), ondelete="CASCADE"),
+        sa.ForeignKeyConstraint(["tenant_id"], [scope_fk_target], name=op.f("fk_calendar_sync_sources_tenant_id_scopes"), ondelete="CASCADE"),
         sa.PrimaryKeyConstraint("id", name=op.f("pk_calendar_sync_sources")),
     )
     for column in ("tenant_id", "calendar_id", "source_kind", "deleted_at"):

src/govoplan_calendar/backend/migrations/versions/9e0f1a2b3c4d_caldav_credentials_outbound_sync.py

@@ -16,10 +16,15 @@ branch_labels = None
 depends_on = None
 
 
+def _scope_fk_target(tables: set[str]) -> str:
+    return "core_scopes.id" if "core_scopes" in tables else "tenancy_tenants.id"
+
+
 def upgrade() -> None:
     bind = op.get_bind()
     inspector = sa.inspect(bind)
     tables = set(inspector.get_table_names())
+    scope_fk_target = _scope_fk_target(tables)
     if "calendar_sync_sources" in tables:
         columns = {column["name"] for column in inspector.get_columns("calendar_sync_sources")}
         add_column_if_missing(columns, "sync_enabled", sa.Column("sync_enabled", sa.Boolean(), server_default=sa.true(), nullable=False))
@@ -47,8 +52,8 @@ def upgrade() -> None:
             sa.Column("metadata", sa.JSON(), nullable=True),
             sa.Column("created_at", sa.DateTime(timezone=True), nullable=False),
             sa.Column("updated_at", sa.DateTime(timezone=True), nullable=False),
-            sa.ForeignKeyConstraint(["created_by_user_id"], ["users.id"], name=op.f("fk_calendar_sync_credentials_created_by_user_id_users"), ondelete="SET NULL"),
+            sa.ForeignKeyConstraint(["created_by_user_id"], ["access_users.id"], name=op.f("fk_calendar_sync_credentials_created_by_user_id_users"), ondelete="SET NULL"),
-            sa.ForeignKeyConstraint(["tenant_id"], ["tenants.id"], name=op.f("fk_calendar_sync_credentials_tenant_id_tenants"), ondelete="CASCADE"),
+            sa.ForeignKeyConstraint(["tenant_id"], [scope_fk_target], name=op.f("fk_calendar_sync_credentials_tenant_id_scopes"), ondelete="CASCADE"),
             sa.PrimaryKeyConstraint("id", name=op.f("pk_calendar_sync_credentials")),
         )
         for column in ("tenant_id", "credential_kind", "created_by_user_id", "deleted_at"):

src/govoplan_calendar/backend/router.py

@@ -5,10 +5,15 @@ from datetime import datetime
 from fastapi import APIRouter, Body, Depends, HTTPException, Query, Response, status
 from sqlalchemy.orm import Session
 
-from govoplan_access.backend.auth.dependencies import ApiPrincipal, get_api_principal, has_scope
+from govoplan_core.auth import ApiPrincipal, get_api_principal, has_scope
+from govoplan_core.api.v1.schemas import DeltaDeletedItem
+from govoplan_core.core.change_sequence import decode_sequence_watermark, encode_sequence_watermark, max_sequence_id, sequence_entries_since, sequence_watermark_is_expired
+from govoplan_calendar.backend.db.models import CalendarEvent
 from govoplan_calendar.backend.ical import ICalendarError, event_to_ics, http_last_modified
 from govoplan_calendar.backend.caldav import CalDAVError
 from govoplan_calendar.backend.schemas import (
+    CalendarCalDavDiscoveryRequest,
+    CalendarCalDavDiscoveryResponse,
     CalendarCalDavDueSyncItemResponse,
     CalendarCalDavDueSyncResponse,
     CalendarCalDavSourceCreateRequest,
@@ -23,24 +28,39 @@ from govoplan_calendar.backend.schemas import (
     CalendarCollectionResponse,
     CalendarCollectionUpdateRequest,
     CalendarEventCreateRequest,
+    CalendarEventDeltaResponse,
     CalendarEventListResponse,
     CalendarEventResponse,
     CalendarEventUpdateRequest,
     CalendarFreeBusyRequest,
     CalendarFreeBusyResponse,
     CalendarIcsImportRequest,
+    CalendarSyncDueSyncItemResponse,
+    CalendarSyncDueSyncResponse,
+    CalendarSyncSourceCreateRequest,
+    CalendarSyncSourceListResponse,
+    CalendarSyncSourceResponse,
+    CalendarSyncSourceSyncRequest,
+    CalendarSyncSourceSyncResponse,
+    CalendarSyncSourceUpdateRequest,
 )
 from govoplan_calendar.backend.service import (
+    CALENDAR_EVENTS_COLLECTION,
+    CALENDAR_EVENT_RESOURCE,
+    CALENDAR_MODULE_ID,
     CalendarError,
     caldav_source_response,
     caldav_sync_response,
     calendar_response,
     create_calendar,
     create_caldav_source,
+    create_sync_source,
     create_event,
     delete_calendar,
     delete_caldav_source,
+    delete_sync_source,
     delete_event,
+    discover_caldav_calendars,
     event_response,
     get_caldav_source,
     get_event,
@@ -49,10 +69,15 @@ from govoplan_calendar.backend.service import (
     list_caldav_sources,
     list_calendars,
     list_events,
+    list_sync_sources,
+    normalize_datetime,
+    sync_due_sources,
     sync_due_caldav_sources,
     sync_caldav_source,
+    sync_source,
     update_calendar,
     update_caldav_source,
+    update_sync_source,
     update_event,
 )
 from govoplan_core.db.session import get_session
@@ -78,10 +103,123 @@ def _event_response(event) -> CalendarEventResponse:
     return CalendarEventResponse.model_validate(event_response(event))
 
 
+def _calendar_event_watermark(session: Session, tenant_id: str) -> str:
+    return encode_sequence_watermark(
+        max_sequence_id(session, tenant_id=tenant_id, module_id=CALENDAR_MODULE_ID, collections=(CALENDAR_EVENTS_COLLECTION,))
+    )
+
+
+def _parse_payload_datetime(value) -> datetime | None:
+    if not isinstance(value, str) or not value:
+        return None
+    try:
+        return datetime.fromisoformat(value)
+    except ValueError:
+        return None
+
+
+def _event_interval_overlaps(payload: dict, *, prefix: str, start_at: datetime | None, end_at: datetime | None) -> bool:
+    event_start = _parse_payload_datetime(payload.get(f"{prefix}start_at"))
+    event_end = _parse_payload_datetime(payload.get(f"{prefix}end_at")) or event_start
+    if event_start is None:
+        return False
+    if start_at is not None and event_end is not None and event_end < normalize_datetime(start_at):
+        return False
+    if end_at is not None and event_start > normalize_datetime(end_at):
+        return False
+    return True
+
+
+def _event_payload_matches_window(entry, *, calendar_id: str | None, start_at: datetime | None, end_at: datetime | None) -> bool:
+    payload = entry.payload or {}
+    current_calendar = payload.get("calendar_id")
+    previous_calendar = payload.get("previous_calendar_id")
+    current_calendar_matches = calendar_id is None or current_calendar == calendar_id
+    previous_calendar_matches = calendar_id is None or previous_calendar == calendar_id
+    return (
+        current_calendar_matches and _event_interval_overlaps(payload, prefix="", start_at=start_at, end_at=end_at)
+    ) or (
+        previous_calendar_matches and _event_interval_overlaps(payload, prefix="previous_", start_at=start_at, end_at=end_at)
+    )
+
+
+def _visible_events_for_delta(
+    session: Session,
+    *,
+    tenant_id: str,
+    event_ids: list[str],
+    calendar_id: str | None,
+    start_at: datetime | None,
+    end_at: datetime | None,
+) -> list[CalendarEvent]:
+    if not event_ids:
+        return []
+    query = session.query(CalendarEvent).filter(
+        CalendarEvent.tenant_id == tenant_id,
+        CalendarEvent.id.in_(event_ids),
+        CalendarEvent.deleted_at.is_(None),
+    )
+    if calendar_id:
+        query = query.filter(CalendarEvent.calendar_id == calendar_id)
+    if start_at is not None:
+        normalized_start = normalize_datetime(start_at)
+        query = query.filter((CalendarEvent.end_at.is_(None)) | (CalendarEvent.end_at >= normalized_start))
+    if end_at is not None:
+        query = query.filter(CalendarEvent.start_at <= normalize_datetime(end_at))
+    return query.order_by(CalendarEvent.start_at.asc(), CalendarEvent.summary.asc(), CalendarEvent.id.asc()).all()
+
+
+def _full_event_delta_response(
+    session: Session,
+    *,
+    tenant_id: str,
+    calendar_id: str | None,
+    start_at: datetime | None,
+    end_at: datetime | None,
+) -> CalendarEventDeltaResponse:
+    events = list_events(session, tenant_id=tenant_id, calendar_id=calendar_id, start_at=start_at, end_at=end_at)
+    return CalendarEventDeltaResponse(
+        events=[_event_response(event) for event in events],
+        deleted=[],
+        watermark=_calendar_event_watermark(session, tenant_id),
+        has_more=False,
+        full=True,
+    )
+
+
+def _event_delta_entries(session: Session, *, tenant_id: str, since: str, limit: int):
+    try:
+        since_sequence = decode_sequence_watermark(since)
+    except ValueError as exc:
+        raise HTTPException(status_code=status.HTTP_400_BAD_REQUEST, detail=str(exc)) from exc
+    if sequence_watermark_is_expired(
+        session,
+        since=since_sequence,
+        tenant_id=tenant_id,
+        module_id=CALENDAR_MODULE_ID,
+        collections=(CALENDAR_EVENTS_COLLECTION,),
+    ):
+        return None, False
+    entries_plus_one = sequence_entries_since(
+        session,
+        since=since_sequence,
+        tenant_id=tenant_id,
+        module_id=CALENDAR_MODULE_ID,
+        collections=(CALENDAR_EVENTS_COLLECTION,),
+        limit=limit + 1,
+    )
+    has_more = len(entries_plus_one) > limit
+    return entries_plus_one[:limit], has_more
+
+
 def _caldav_source_response(source) -> CalendarCalDavSourceResponse:
     return CalendarCalDavSourceResponse.model_validate(caldav_source_response(source))
 
 
+def _sync_source_response(source) -> CalendarSyncSourceResponse:
+    return CalendarSyncSourceResponse.model_validate(caldav_source_response(source))
+
+
 @router.get("/calendars", response_model=CalendarCollectionListResponse)
 def api_list_calendars(
     principal: ApiPrincipal = Depends(get_api_principal),
@@ -107,7 +245,7 @@ def api_create_calendar(
         return _calendar_response(calendar)
     except CalendarError as exc:
         session.rollback()
-        raise HTTPException(status_code=status.HTTP_422_UNPROCESSABLE_ENTITY, detail=str(exc)) from exc
+        raise HTTPException(status_code=status.HTTP_422_UNPROCESSABLE_CONTENT, detail=str(exc)) from exc
 
 
 @router.patch("/calendars/{calendar_id}", response_model=CalendarCollectionResponse)
@@ -142,7 +280,124 @@ def api_delete_calendar(
         return Response(status_code=status.HTTP_204_NO_CONTENT)
     except CalendarError as exc:
         session.rollback()
-        raise HTTPException(status_code=status.HTTP_422_UNPROCESSABLE_ENTITY, detail=str(exc)) from exc
+        raise HTTPException(status_code=status.HTTP_422_UNPROCESSABLE_CONTENT, detail=str(exc)) from exc
+
+
+@router.get("/sync-sources", response_model=CalendarSyncSourceListResponse)
+def api_list_sync_sources(
+    calendar_id: str | None = None,
+    source_kind: str | None = None,
+    principal: ApiPrincipal = Depends(get_api_principal),
+    session: Session = Depends(get_session),
+):
+    _require_scope(principal, "calendar:calendar:read")
+    sources = list_sync_sources(session, tenant_id=principal.tenant_id, calendar_id=calendar_id, source_kind=source_kind)
+    return CalendarSyncSourceListResponse(sources=[_sync_source_response(source) for source in sources])
+
+
+@router.post("/sync-sources", response_model=CalendarSyncSourceResponse, status_code=status.HTTP_201_CREATED)
+def api_create_sync_source(
+    payload: CalendarSyncSourceCreateRequest,
+    principal: ApiPrincipal = Depends(get_api_principal),
+    session: Session = Depends(get_session),
+):
+    _require_scope(principal, "calendar:calendar:admin")
+    try:
+        source = create_sync_source(session, tenant_id=principal.tenant_id, user_id=principal.user.id, payload=payload)
+        session.commit()
+        session.refresh(source)
+        return _sync_source_response(source)
+    except CalendarError as exc:
+        session.rollback()
+        raise HTTPException(status_code=status.HTTP_422_UNPROCESSABLE_CONTENT, detail=str(exc)) from exc
+
+
+@router.patch("/sync-sources/{source_id}", response_model=CalendarSyncSourceResponse)
+def api_update_sync_source(
+    source_id: str,
+    payload: CalendarSyncSourceUpdateRequest,
+    principal: ApiPrincipal = Depends(get_api_principal),
+    session: Session = Depends(get_session),
+):
+    _require_scope(principal, "calendar:calendar:admin")
+    try:
+        source = update_sync_source(session, tenant_id=principal.tenant_id, source_id=source_id, payload=payload)
+        session.commit()
+        session.refresh(source)
+        return _sync_source_response(source)
+    except CalendarError as exc:
+        session.rollback()
+        raise HTTPException(status_code=status.HTTP_422_UNPROCESSABLE_CONTENT, detail=str(exc)) from exc
+
+
+@router.delete("/sync-sources/{source_id}", status_code=status.HTTP_204_NO_CONTENT)
+def api_delete_sync_source(
+    source_id: str,
+    principal: ApiPrincipal = Depends(get_api_principal),
+    session: Session = Depends(get_session),
+):
+    _require_scope(principal, "calendar:calendar:admin")
+    try:
+        delete_sync_source(session, tenant_id=principal.tenant_id, source_id=source_id)
+        session.commit()
+        return Response(status_code=status.HTTP_204_NO_CONTENT)
+    except CalendarError as exc:
+        session.rollback()
+        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail=str(exc)) from exc
+
+
+@router.post("/sync-sources/{source_id}/sync", response_model=CalendarSyncSourceSyncResponse)
+def api_sync_source(
+    source_id: str,
+    payload: CalendarSyncSourceSyncRequest | None = None,
+    principal: ApiPrincipal = Depends(get_api_principal),
+    session: Session = Depends(get_session),
+):
+    _require_scope(principal, "calendar:event:import")
+    payload = payload or CalendarSyncSourceSyncRequest()
+    try:
+        source, stats = sync_source(
+            session,
+            tenant_id=principal.tenant_id,
+            user_id=principal.user.id,
+            source_id=source_id,
+            password=payload.password,
+            bearer_token=payload.bearer_token,
+            force_full=payload.force_full,
+        )
+        session.commit()
+        session.refresh(source)
+        return CalendarSyncSourceSyncResponse.model_validate(caldav_sync_response(source, stats))
+    except (CalendarError, CalDAVError, ICalendarError) as exc:
+        session.rollback()
+        raise HTTPException(status_code=status.HTTP_422_UNPROCESSABLE_CONTENT, detail=str(exc)) from exc
+
+
+@router.post("/sync-sources/sync-due", response_model=CalendarSyncDueSyncResponse)
+def api_sync_due_sources(
+    limit: int = Query(default=50, ge=1, le=200),
+    principal: ApiPrincipal = Depends(get_api_principal),
+    session: Session = Depends(get_session),
+):
+    _require_scope(principal, "calendar:event:import")
+    results = sync_due_sources(session, tenant_id=principal.tenant_id, user_id=principal.user.id, limit=limit)
+    session.commit()
+    return CalendarSyncDueSyncResponse(
+        results=[
+            CalendarSyncDueSyncItemResponse(
+                source_id=item.source_id,
+                calendar_id=item.calendar_id,
+                status=item.status,
+                error=item.error,
+                created=item.stats.created if item.stats else 0,
+                updated=item.stats.updated if item.stats else 0,
+                deleted=item.stats.deleted if item.stats else 0,
+                unchanged=item.stats.unchanged if item.stats else 0,
+                fetched=item.stats.fetched if item.stats else 0,
+            )
+            for item in results
+        ]
+    )
 
 
 @router.get("/caldav/sources", response_model=CalendarCalDavSourceListResponse)
@@ -156,6 +411,20 @@ def api_list_caldav_sources(
     return CalendarCalDavSourceListResponse(sources=[_caldav_source_response(source) for source in sources])
 
 
+@router.post("/caldav/discover", response_model=CalendarCalDavDiscoveryResponse)
+def api_discover_caldav_calendars(
+    payload: CalendarCalDavDiscoveryRequest,
+    principal: ApiPrincipal = Depends(get_api_principal),
+    session: Session = Depends(get_session),
+):
+    _require_scope(principal, "calendar:calendar:admin")
+    try:
+        calendars = discover_caldav_calendars(session, tenant_id=principal.tenant_id, payload=payload)
+        return CalendarCalDavDiscoveryResponse(calendars=calendars)
+    except (CalendarError, CalDAVError) as exc:
+        raise HTTPException(status_code=status.HTTP_422_UNPROCESSABLE_CONTENT, detail=str(exc)) from exc
+
+
 @router.post("/caldav/sources", response_model=CalendarCalDavSourceResponse, status_code=status.HTTP_201_CREATED)
 def api_create_caldav_source(
     payload: CalendarCalDavSourceCreateRequest,
@@ -170,7 +439,7 @@ def api_create_caldav_source(
         return _caldav_source_response(source)
     except CalendarError as exc:
         session.rollback()
-        raise HTTPException(status_code=status.HTTP_422_UNPROCESSABLE_ENTITY, detail=str(exc)) from exc
+        raise HTTPException(status_code=status.HTTP_422_UNPROCESSABLE_CONTENT, detail=str(exc)) from exc
 
 
 @router.patch("/caldav/sources/{source_id}", response_model=CalendarCalDavSourceResponse)
@@ -188,7 +457,7 @@ def api_update_caldav_source(
         return _caldav_source_response(source)
     except CalendarError as exc:
         session.rollback()
-        raise HTTPException(status_code=status.HTTP_422_UNPROCESSABLE_ENTITY, detail=str(exc)) from exc
+        raise HTTPException(status_code=status.HTTP_422_UNPROCESSABLE_CONTENT, detail=str(exc)) from exc
 
 
 @router.delete("/caldav/sources/{source_id}", status_code=status.HTTP_204_NO_CONTENT)
@@ -231,7 +500,7 @@ def api_sync_caldav_source(
         return CalendarCalDavSyncResponse.model_validate(caldav_sync_response(source, stats))
     except (CalendarError, CalDAVError, ICalendarError) as exc:
         session.rollback()
-        raise HTTPException(status_code=status.HTTP_422_UNPROCESSABLE_ENTITY, detail=str(exc)) from exc
+        raise HTTPException(status_code=status.HTTP_422_UNPROCESSABLE_CONTENT, detail=str(exc)) from exc
 
 
 @router.post("/caldav/sync-due", response_model=CalendarCalDavDueSyncResponse)
@@ -274,6 +543,57 @@ def api_list_events(
     return CalendarEventListResponse(events=[_event_response(event) for event in events])
 
 
+@router.get("/events/delta", response_model=CalendarEventDeltaResponse)
+def api_list_events_delta(
+    calendar_id: str | None = None,
+    start_at: datetime | None = Query(default=None),
+    end_at: datetime | None = Query(default=None),
+    since: str | None = None,
+    limit: int = Query(default=500, ge=1, le=1000),
+    principal: ApiPrincipal = Depends(get_api_principal),
+    session: Session = Depends(get_session),
+):
+    _require_scope(principal, "calendar:event:read")
+    if since is None:
+        return _full_event_delta_response(session, tenant_id=principal.tenant_id, calendar_id=calendar_id, start_at=start_at, end_at=end_at)
+    entries, has_more = _event_delta_entries(session, tenant_id=principal.tenant_id, since=since, limit=limit)
+    if entries is None:
+        return _full_event_delta_response(session, tenant_id=principal.tenant_id, calendar_id=calendar_id, start_at=start_at, end_at=end_at)
+    scoped_entries = [
+        entry
+        for entry in entries
+        if entry.resource_type == CALENDAR_EVENT_RESOURCE and _event_payload_matches_window(entry, calendar_id=calendar_id, start_at=start_at, end_at=end_at)
+    ]
+    changed_ids = list(dict.fromkeys(entry.resource_id for entry in scoped_entries if entry.operation != "deleted"))
+    visible_events = _visible_events_for_delta(
+        session,
+        tenant_id=principal.tenant_id,
+        event_ids=changed_ids,
+        calendar_id=calendar_id,
+        start_at=start_at,
+        end_at=end_at,
+    )
+    visible_ids = {event.id for event in visible_events}
+    deleted = [
+        DeltaDeletedItem(
+            id=entry.resource_id,
+            resource_type=entry.resource_type,
+            revision=encode_sequence_watermark(entry.id),
+            deleted_at=entry.created_at if entry.operation == "deleted" else None,
+        )
+        for entry in scoped_entries
+        if entry.resource_id not in visible_ids
+    ]
+    watermark = encode_sequence_watermark(entries[-1].id) if has_more and entries else _calendar_event_watermark(session, principal.tenant_id)
+    return CalendarEventDeltaResponse(
+        events=[_event_response(event) for event in visible_events],
+        deleted=deleted,
+        watermark=watermark,
+        has_more=has_more,
+        full=False,
+    )
+
+
 @router.post("/events", response_model=CalendarEventResponse, status_code=status.HTTP_201_CREATED)
 def api_create_event(
     payload: CalendarEventCreateRequest,
@@ -288,7 +608,7 @@ def api_create_event(
         return _event_response(event)
     except CalendarError as exc:
         session.rollback()
-        raise HTTPException(status_code=status.HTTP_422_UNPROCESSABLE_ENTITY, detail=str(exc)) from exc
+        raise HTTPException(status_code=status.HTTP_422_UNPROCESSABLE_CONTENT, detail=str(exc)) from exc
 
 
 @router.get("/events/{event_id}", response_model=CalendarEventResponse)
@@ -319,7 +639,7 @@ def api_update_event(
         return _event_response(event)
     except CalendarError as exc:
         session.rollback()
-        raise HTTPException(status_code=status.HTTP_422_UNPROCESSABLE_ENTITY, detail=str(exc)) from exc
+        raise HTTPException(status_code=status.HTTP_422_UNPROCESSABLE_CONTENT, detail=str(exc)) from exc
 
 
 @router.delete("/events/{event_id}", status_code=status.HTTP_204_NO_CONTENT)
@@ -330,7 +650,7 @@ def api_delete_event(
 ):
     _require_any_scope(principal, "calendar:event:delete", "calendar:event:write")
     try:
-        delete_event(session, tenant_id=principal.tenant_id, event_id=event_id)
+        delete_event(session, tenant_id=principal.tenant_id, event_id=event_id, user_id=principal.user.id)
         session.commit()
         return Response(status_code=status.HTTP_204_NO_CONTENT)
     except CalendarError as exc:
@@ -362,7 +682,7 @@ def api_import_ics_event(
         return _event_response(event)
     except (CalendarError, ICalendarError) as exc:
         session.rollback()
-        raise HTTPException(status_code=status.HTTP_422_UNPROCESSABLE_ENTITY, detail=str(exc)) from exc
+        raise HTTPException(status_code=status.HTTP_422_UNPROCESSABLE_CONTENT, detail=str(exc)) from exc
 
 
 @router.get("/events/{event_id}/ics")
@@ -404,4 +724,4 @@ def api_freebusy(
         )
         return CalendarFreeBusyResponse(start_at=payload.start_at, end_at=payload.end_at, busy=busy)
     except CalendarError as exc:
-        raise HTTPException(status_code=status.HTTP_422_UNPROCESSABLE_ENTITY, detail=str(exc)) from exc
+        raise HTTPException(status_code=status.HTTP_422_UNPROCESSABLE_CONTENT, detail=str(exc)) from exc

src/govoplan_calendar/backend/schemas.py

@@ -5,12 +5,15 @@ from typing import Any, Literal
 
 from pydantic import BaseModel, ConfigDict, Field, SecretStr
 
+from govoplan_core.api.v1.schemas import DeltaDeletedItem
+
 
 CalendarOwnerType = Literal["tenant", "user", "group", "resource"]
 CalendarVisibility = Literal["private", "tenant", "shared", "public"]
 CalendarDeleteEventAction = Literal["delete", "move"]
 CalendarSyncAuthType = Literal["none", "basic", "bearer"]
 CalendarSyncDirection = Literal["inbound", "two_way"]
+CalendarSyncSourceKind = Literal["caldav", "ics", "webcal", "graph", "ews"]
 CalendarCalDavConflictPolicy = Literal["etag", "overwrite"]
 
 
@@ -70,9 +73,10 @@ class CalendarCollectionListResponse(BaseModel):
     calendars: list[CalendarCollectionResponse] = Field(default_factory=list)
 
 
-class CalendarCalDavSourceCreateRequest(BaseModel):
+class CalendarSyncSourceCreateRequest(BaseModel):
     model_config = ConfigDict(extra="forbid")
 
+    source_kind: CalendarSyncSourceKind = "caldav"
     calendar_id: str
     collection_url: str = Field(min_length=1, max_length=1000)
     display_name: str | None = Field(default=None, max_length=255)
@@ -88,7 +92,11 @@ class CalendarCalDavSourceCreateRequest(BaseModel):
     metadata: dict[str, Any] = Field(default_factory=dict)
 
 
-class CalendarCalDavSourceUpdateRequest(BaseModel):
+class CalendarCalDavSourceCreateRequest(CalendarSyncSourceCreateRequest):
+    source_kind: Literal["caldav"] = "caldav"
+
+
+class CalendarSyncSourceUpdateRequest(BaseModel):
     model_config = ConfigDict(extra="forbid")
 
     calendar_id: str | None = None
@@ -108,7 +116,11 @@ class CalendarCalDavSourceUpdateRequest(BaseModel):
     metadata: dict[str, Any] | None = None
 
 
-class CalendarCalDavSourceResponse(BaseModel):
+class CalendarCalDavSourceUpdateRequest(CalendarSyncSourceUpdateRequest):
+    pass
+
+
+class CalendarSyncSourceResponse(BaseModel):
     id: str
     tenant_id: str
     calendar_id: str
@@ -135,11 +147,44 @@ class CalendarCalDavSourceResponse(BaseModel):
     metadata: dict[str, Any] = Field(default_factory=dict)
 
 
+class CalendarCalDavSourceResponse(CalendarSyncSourceResponse):
+    pass
+
+
+class CalendarSyncSourceListResponse(BaseModel):
+    sources: list[CalendarSyncSourceResponse] = Field(default_factory=list)
+
+
 class CalendarCalDavSourceListResponse(BaseModel):
     sources: list[CalendarCalDavSourceResponse] = Field(default_factory=list)
 
 
-class CalendarCalDavSyncRequest(BaseModel):
+class CalendarCalDavDiscoveryRequest(BaseModel):
+    model_config = ConfigDict(extra="forbid")
+
+    url: str = Field(min_length=1, max_length=1000)
+    source_id: str | None = None
+    auth_type: CalendarSyncAuthType | None = None
+    username: str | None = Field(default=None, max_length=255)
+    credential_ref: str | None = Field(default=None, max_length=255)
+    password: SecretStr | None = None
+    bearer_token: SecretStr | None = None
+
+
+class CalendarCalDavDiscoveryCalendarResponse(BaseModel):
+    collection_url: str
+    href: str
+    display_name: str | None = None
+    color: str | None = None
+    ctag: str | None = None
+    sync_token: str | None = None
+
+
+class CalendarCalDavDiscoveryResponse(BaseModel):
+    calendars: list[CalendarCalDavDiscoveryCalendarResponse] = Field(default_factory=list)
+
+
+class CalendarSyncSourceSyncRequest(BaseModel):
     model_config = ConfigDict(extra="forbid")
 
     password: str | None = None
@@ -147,8 +192,12 @@ class CalendarCalDavSyncRequest(BaseModel):
     force_full: bool = False
 
 
-class CalendarCalDavSyncResponse(BaseModel):
+class CalendarCalDavSyncRequest(CalendarSyncSourceSyncRequest):
-    source: CalendarCalDavSourceResponse
+    pass
+
+
+class CalendarSyncSourceSyncResponse(BaseModel):
+    source: CalendarSyncSourceResponse
     created: int = 0
     updated: int = 0
     deleted: int = 0
@@ -161,7 +210,11 @@ class CalendarCalDavSyncResponse(BaseModel):
     errors: list[str] = Field(default_factory=list)
 
 
-class CalendarCalDavDueSyncItemResponse(BaseModel):
+class CalendarCalDavSyncResponse(CalendarSyncSourceSyncResponse):
+    source: CalendarCalDavSourceResponse
+
+
+class CalendarSyncDueSyncItemResponse(BaseModel):
     source_id: str
     calendar_id: str
     status: str
@@ -173,6 +226,14 @@ class CalendarCalDavDueSyncItemResponse(BaseModel):
     fetched: int = 0
 
 
+class CalendarCalDavDueSyncItemResponse(CalendarSyncDueSyncItemResponse):
+    pass
+
+
+class CalendarSyncDueSyncResponse(BaseModel):
+    results: list[CalendarSyncDueSyncItemResponse] = Field(default_factory=list)
+
+
 class CalendarCalDavDueSyncResponse(BaseModel):
     results: list[CalendarCalDavDueSyncItemResponse] = Field(default_factory=list)
 
@@ -283,6 +344,14 @@ class CalendarEventListResponse(BaseModel):
     events: list[CalendarEventResponse] = Field(default_factory=list)
 
 
+class CalendarEventDeltaResponse(BaseModel):
+    events: list[CalendarEventResponse] = Field(default_factory=list)
+    deleted: list[DeltaDeletedItem] = Field(default_factory=list)
+    watermark: str | None = None
+    has_more: bool = False
+    full: bool = False
+
+
 class CalendarFreeBusyRequest(BaseModel):
     model_config = ConfigDict(extra="forbid")
 

src/govoplan_calendar/backend/tasks.py

@@ -5,11 +5,11 @@ from celery import shared_task
 
 @shared_task(name="govoplan_calendar.sync_due_caldav_sources")
 def sync_due_caldav_sources_task(tenant_id: str | None = None, limit: int = 50) -> list[dict[str, object]]:
-    from govoplan_calendar.backend.service import sync_due_caldav_sources
+    from govoplan_calendar.backend.service import sync_due_sources
     from govoplan_core.db.session import get_database
 
     with get_database().SessionLocal() as session:
-        results = sync_due_caldav_sources(session, tenant_id=tenant_id, limit=limit)
+        results = sync_due_sources(session, tenant_id=tenant_id, limit=limit)
         session.commit()
         return [
             {

tests/test_caldav.py

@@ -9,7 +9,7 @@ from sqlalchemy import create_engine
 from sqlalchemy.orm import sessionmaker
 
 from govoplan_access.backend.db import models as access_models  # noqa: F401 - populate users/accounts tables
-from govoplan_calendar.backend.caldav import CalDAVObject, CalDAVPreconditionFailed, CalDAVReportResult, CalDAVWriteResult, parse_multistatus
+from govoplan_calendar.backend.caldav import CalDAVClient, CalDAVError, CalDAVNotFound, CalDAVObject, CalDAVPreconditionFailed, CalDAVReportResult, CalDAVWriteResult, parse_multistatus
 from govoplan_calendar.backend.db.models import CalendarEvent, CalendarSyncCredential, CalendarSyncSource
 from govoplan_calendar.backend.schemas import CalendarCalDavSourceCreateRequest, CalendarCollectionCreateRequest, CalendarEventCreateRequest, CalendarEventUpdateRequest
 from govoplan_calendar.backend.service import (
@@ -19,13 +19,16 @@ from govoplan_calendar.backend.service import (
     create_calendar,
     create_caldav_source,
     create_event,
+    delete_calendar,
     delete_event,
+    list_caldav_sources,
     list_freebusy,
     sync_caldav_source,
     sync_due_caldav_sources,
     update_event,
 )
 from govoplan_core.db.base import Base
+from govoplan_core.tenancy.scope import create_scope_tables
 from govoplan_tenancy.backend.db.models import Tenant
 
 
@@ -36,12 +39,14 @@ class FakeCalDAVClient:
         list_result: CalDAVReportResult | None = None,
         sync_result: CalDAVReportResult | None = None,
         objects: dict[str, str] | None = None,
+        fetch_not_found: set[str] | None = None,
         put_etags: list[str | None] | None = None,
         fail_precondition: bool = False,
     ) -> None:
         self.list_result = list_result or CalDAVReportResult()
         self.sync_result = sync_result
         self.objects = objects or {}
+        self.fetch_not_found = fetch_not_found or set()
         self.put_etags = put_etags or ['"etag-written"']
         self.fail_precondition = fail_precondition
         self.fetched: list[str] = []
@@ -61,6 +66,8 @@ class FakeCalDAVClient:
 
     def fetch_object(self, href: str) -> str:
         self.fetched.append(href)
+        if href in self.fetch_not_found:
+            raise CalDAVNotFound(f"GET {href} returned HTTP 404")
         return self.objects[href]
 
     def put_object(self, href: str, ics: str, *, etag: str | None = None, create: bool = False, overwrite: bool = False) -> CalDAVWriteResult:
@@ -116,10 +123,109 @@ END:VCALENDAR</C:calendar-data>
         self.assertIn("BEGIN:VEVENT", result.objects[0].calendar_data or "")
         self.assertTrue(result.objects[1].deleted)
 
+    def test_discovery_resolves_nextcloud_dav_root_to_calendar_collections(self) -> None:
+        requests: list[tuple[str, str, str | None]] = []
+
+        def transport(method: str, url: str, headers: dict[str, str], body: bytes | None, timeout: int):
+            requests.append((method, url, headers.get("Authorization")))
+            if url == "https://cloud.example.test/remote.php/dav/":
+                return 207, {}, b"""<?xml version="1.0" encoding="utf-8"?>
+<D:multistatus xmlns:D="DAV:">
+  <D:response>
+    <D:href>/remote.php/dav/</D:href>
+    <D:propstat>
+      <D:prop>
+        <D:current-user-principal><D:href>/remote.php/dav/principals/users/ada/</D:href></D:current-user-principal>
+      </D:prop>
+      <D:status>HTTP/1.1 200 OK</D:status>
+    </D:propstat>
+  </D:response>
+</D:multistatus>"""
+            if url == "https://cloud.example.test/remote.php/dav/principals/users/ada/":
+                return 207, {}, b"""<?xml version="1.0" encoding="utf-8"?>
+<D:multistatus xmlns:D="DAV:" xmlns:C="urn:ietf:params:xml:ns:caldav">
+  <D:response>
+    <D:href>/remote.php/dav/principals/users/ada/</D:href>
+    <D:propstat>
+      <D:prop>
+        <C:calendar-home-set><D:href>/remote.php/dav/calendars/ada/</D:href></C:calendar-home-set>
+      </D:prop>
+      <D:status>HTTP/1.1 200 OK</D:status>
+    </D:propstat>
+  </D:response>
+</D:multistatus>"""
+            if url == "https://cloud.example.test/remote.php/dav/calendars/ada/":
+                return 207, {}, b"""<?xml version="1.0" encoding="utf-8"?>
+<D:multistatus xmlns:D="DAV:" xmlns:C="urn:ietf:params:xml:ns:caldav" xmlns:CS="http://calendarserver.org/ns/" xmlns:ICAL="http://apple.com/ns/ical/">
+  <D:response>
+    <D:href>/remote.php/dav/calendars/ada/</D:href>
+    <D:propstat>
+      <D:prop><D:resourcetype><D:collection/></D:resourcetype></D:prop>
+      <D:status>HTTP/1.1 200 OK</D:status>
+    </D:propstat>
+  </D:response>
+  <D:response>
+    <D:href>/remote.php/dav/calendars/ada/personal/</D:href>
+    <D:propstat>
+      <D:prop>
+        <D:displayname>Personal</D:displayname>
+        <D:resourcetype><D:collection/><C:calendar/></D:resourcetype>
+        <C:supported-calendar-component-set><C:comp name="VEVENT"/></C:supported-calendar-component-set>
+        <ICAL:calendar-color>#44aa99ff</ICAL:calendar-color>
+        <CS:getctag>ctag-1</CS:getctag>
+      </D:prop>
+      <D:status>HTTP/1.1 200 OK</D:status>
+    </D:propstat>
+  </D:response>
+</D:multistatus>"""
+            raise AssertionError(f"Unexpected {method} {url}")
+
+        client = CalDAVClient(collection_url="https://cloud.example.test/remote.php/dav", username="ada", password="secret", transport=transport)
+        calendars = client.discover_calendars()
+
+        self.assertEqual(len(calendars), 1)
+        self.assertEqual(calendars[0].collection_url, "https://cloud.example.test/remote.php/dav/calendars/ada/personal/")
+        self.assertEqual(calendars[0].display_name, "Personal")
+        self.assertEqual(calendars[0].color, "#44aa99ff")
+        self.assertEqual(requests[0][2], "Basic YWRhOnNlY3JldA==")
+
+    def test_discovery_accepts_host_path_url_without_scheme(self) -> None:
+        requested_urls: list[str] = []
+
+        def transport(method: str, url: str, headers: dict[str, str], body: bytes | None, timeout: int):
+            requested_urls.append(url)
+            return 207, {}, b"""<?xml version="1.0" encoding="utf-8"?>
+<D:multistatus xmlns:D="DAV:" xmlns:C="urn:ietf:params:xml:ns:caldav">
+  <D:response>
+    <D:href>/remote.php/dav/calendars/ada/personal/</D:href>
+    <D:propstat>
+      <D:prop>
+        <D:displayname>Personal</D:displayname>
+        <D:resourcetype><D:collection/><C:calendar/></D:resourcetype>
+        <C:supported-calendar-component-set><C:comp name="VEVENT"/></C:supported-calendar-component-set>
+      </D:prop>
+      <D:status>HTTP/1.1 200 OK</D:status>
+    </D:propstat>
+  </D:response>
+</D:multistatus>"""
+
+        client = CalDAVClient(collection_url="cloud.example.test/remote.php/dav", transport=transport)
+        calendars = client.discover_calendars()
+
+        self.assertEqual(requested_urls[0], "https://cloud.example.test/remote.php/dav/")
+        self.assertEqual(calendars[0].collection_url, "https://cloud.example.test/remote.php/dav/calendars/ada/personal/")
+
+    def test_discovery_reports_relative_url_as_caldav_error(self) -> None:
+        client = CalDAVClient(collection_url="/remote.php/dav")
+
+        with self.assertRaisesRegex(CalDAVError, "unknown url type"):
+            client.discover_calendars()
+
 
 class CalDAVSyncTests(unittest.TestCase):
     def setUp(self) -> None:
         self.engine = create_engine("sqlite:///:memory:")
+        create_scope_tables(self.engine)
         Base.metadata.create_all(bind=self.engine)
         self.Session = sessionmaker(bind=self.engine)
 
@@ -153,6 +259,79 @@ class CalDAVSyncTests(unittest.TestCase):
         self.assertEqual(client.username, "ada")
         self.assertEqual(client.password, "secret")
 
+    def test_delete_calendar_retires_caldav_source_and_credential(self) -> None:
+        session = self.Session()
+        session.add(Tenant(id="tenant-1", slug="tenant-1", name="Tenant"))
+        calendar = create_calendar(session, tenant_id="tenant-1", user_id=None, payload=CalendarCollectionCreateRequest(name="Remote"))
+        source = create_caldav_source(
+            session,
+            tenant_id="tenant-1",
+            user_id=None,
+            payload=CalendarCalDavSourceCreateRequest(
+                calendar_id=calendar.id,
+                collection_url="https://dav.example.test/cal",
+                auth_type="basic",
+                username="ada",
+                password="secret",
+            ),
+        )
+        session.commit()
+
+        delete_calendar(session, tenant_id="tenant-1", calendar_id=calendar.id)
+        session.commit()
+
+        credential = session.query(CalendarSyncCredential).one()
+        self.assertIsNotNone(source.deleted_at)
+        self.assertIsNotNone(credential.deleted_at)
+        self.assertEqual(list_caldav_sources(session, tenant_id="tenant-1"), [])
+
+    def test_create_source_retires_orphaned_source_for_deleted_calendar(self) -> None:
+        session = self.Session()
+        session.add(Tenant(id="tenant-1", slug="tenant-1", name="Tenant"))
+        old_calendar = create_calendar(session, tenant_id="tenant-1", user_id=None, payload=CalendarCollectionCreateRequest(name="Old"))
+        old_source = create_caldav_source(
+            session,
+            tenant_id="tenant-1",
+            user_id=None,
+            payload=CalendarCalDavSourceCreateRequest(calendar_id=old_calendar.id, collection_url="https://dav.example.test/cal"),
+        )
+        old_calendar.deleted_at = datetime(2026, 7, 7, 12, 0, tzinfo=timezone.utc)
+        new_calendar = create_calendar(session, tenant_id="tenant-1", user_id=None, payload=CalendarCollectionCreateRequest(name="New"))
+        session.commit()
+
+        new_source = create_caldav_source(
+            session,
+            tenant_id="tenant-1",
+            user_id=None,
+            payload=CalendarCalDavSourceCreateRequest(calendar_id=new_calendar.id, collection_url="https://dav.example.test/cal"),
+        )
+        session.commit()
+
+        self.assertIsNotNone(old_source.deleted_at)
+        self.assertEqual(new_source.calendar_id, new_calendar.id)
+        self.assertEqual([source.id for source in list_caldav_sources(session, tenant_id="tenant-1")], [new_source.id])
+
+    def test_create_source_reports_active_duplicate_as_calendar_error(self) -> None:
+        session = self.Session()
+        session.add(Tenant(id="tenant-1", slug="tenant-1", name="Tenant"))
+        first = create_calendar(session, tenant_id="tenant-1", user_id=None, payload=CalendarCollectionCreateRequest(name="First"))
+        second = create_calendar(session, tenant_id="tenant-1", user_id=None, payload=CalendarCollectionCreateRequest(name="Second"))
+        create_caldav_source(
+            session,
+            tenant_id="tenant-1",
+            user_id=None,
+            payload=CalendarCalDavSourceCreateRequest(calendar_id=first.id, collection_url="https://dav.example.test/cal"),
+        )
+        session.commit()
+
+        with self.assertRaisesRegex(CalendarError, "already linked"):
+            create_caldav_source(
+                session,
+                tenant_id="tenant-1",
+                user_id=None,
+                payload=CalendarCalDavSourceCreateRequest(calendar_id=second.id, collection_url="https://dav.example.test/cal"),
+            )
+
     def test_due_sync_runs_due_sources_and_reschedules(self) -> None:
         session = self.Session()
         session.add(Tenant(id="tenant-1", slug="tenant-1", name="Tenant"))
@@ -381,6 +560,57 @@ class CalDAVSyncTests(unittest.TestCase):
         self.assertEqual(source.sync_token, "token-2")
         self.assertIsNotNone(event.deleted_at)
 
+    def test_missing_resource_during_fetch_is_treated_as_remote_delete(self) -> None:
+        session = self.Session()
+        tenant = Tenant(id="tenant-1", slug="tenant-1", name="Tenant")
+        session.add(tenant)
+        calendar = create_calendar(session, tenant_id="tenant-1", user_id=None, payload=CalendarCollectionCreateRequest(name="Remote"))
+        source = create_caldav_source(
+            session,
+            tenant_id="tenant-1",
+            user_id=None,
+            payload=CalendarCalDavSourceCreateRequest(calendar_id=calendar.id, collection_url="https://dav.example.test/cal"),
+        )
+        source.sync_token = "token-1"
+        event = CalendarEvent(
+            tenant_id="tenant-1",
+            calendar_id=calendar.id,
+            uid="event-1@example.test",
+            recurrence_id=None,
+            summary="Remote",
+            status="CONFIRMED",
+            transparency="OPAQUE",
+            classification="PUBLIC",
+            start_at=datetime(2026, 7, 8, 9, 0, tzinfo=timezone.utc),
+            all_day=False,
+            attendees=[],
+            categories=[],
+            rdate=[],
+            exdate=[],
+            reminders=[],
+            attachments=[],
+            related_to=[],
+            source_kind="caldav",
+            source_href="https://dav.example.test/cal/event-1.ics",
+            icalendar={},
+            metadata_={"caldav": {"source_id": source.id}},
+        )
+        session.add(event)
+        session.commit()
+
+        client = FakeCalDAVClient(
+            sync_result=CalDAVReportResult(objects=[CalDAVObject(href="/cal/event-1.ics", etag='"gone"', calendar_data=None)], sync_token="token-2"),
+            fetch_not_found={"/cal/event-1.ics"},
+        )
+        source, stats = sync_caldav_source(session, tenant_id="tenant-1", user_id=None, source_id=source.id, client=client)
+        session.commit()
+
+        self.assertTrue(stats.used_sync_token)
+        self.assertEqual(stats.deleted, 1)
+        self.assertEqual(source.last_status, "ok")
+        self.assertEqual(source.sync_token, "token-2")
+        self.assertIsNotNone(event.deleted_at)
+
 
 def recurring_resource() -> str:
     return """BEGIN:VCALENDAR

tests/test_ical.py

@@ -92,6 +92,7 @@ END:VCALENDAR
         self.assertEqual(event["start_at"], datetime(2026, 7, 8, 7, 0, tzinfo=timezone.utc))
         self.assertEqual(event["end_at"], datetime(2026, 7, 8, 8, 30, tzinfo=timezone.utc))
         self.assertEqual(event["duration_seconds"], 5400)
+        self.assertTrue(event["icalendar"]["standard"]["uses_duration"])
         self.assertEqual(event["description"], "Line one\nLine two")
         self.assertEqual(event["location"], "Room; 1")
         self.assertEqual(event["timezone"], "Europe/Berlin")
@@ -164,6 +165,38 @@ END:VCALENDAR
         self.assertIn("BEGIN:VALARM", ics)
         self.assertIn("TRIGGER:-PT15M", ics)
 
+    def test_generated_ics_preserves_duration_when_source_used_duration(self) -> None:
+        event = SimpleNamespace(
+            uid="event-duration@example.test",
+            start_at=datetime(2026, 7, 8, 7, 0, tzinfo=timezone.utc),
+            end_at=datetime(2026, 7, 8, 8, 30, tzinfo=timezone.utc),
+            duration_seconds=5400,
+            all_day=False,
+            timezone="Europe/Berlin",
+            summary="Duration",
+            sequence=0,
+            status="CONFIRMED",
+            transparency="OPAQUE",
+            classification="PUBLIC",
+            description=None,
+            location=None,
+            categories=[],
+            rrule=None,
+            organizer=None,
+            attendees=[],
+            rdate=[],
+            exdate=[],
+            reminders=[],
+            attachments=[],
+            related_to=[],
+            icalendar={"standard": {"uses_duration": True}},
+        )
+
+        ics = event_to_ics(event)
+
+        self.assertIn("DURATION:PT1H30M", ics)
+        self.assertNotIn("DTEND", ics)
+
     def test_expand_event_occurrences_applies_rrule_rdate_and_exdate(self) -> None:
         parsed = parse_vevent(
             """BEGIN:VCALENDAR

tests/test_sync_sources.py

@@ -0,0 +1,173 @@
+from __future__ import annotations
+
+import json
+import unittest
+from datetime import datetime, timezone
+from unittest.mock import patch
+
+from sqlalchemy import create_engine
+from sqlalchemy.orm import sessionmaker
+
+from govoplan_access.backend.db import models as access_models  # noqa: F401 - populate users/accounts tables
+from govoplan_calendar.backend.db.models import CalendarEvent
+from govoplan_calendar.backend.schemas import CalendarCollectionCreateRequest, CalendarEventCreateRequest, CalendarSyncSourceCreateRequest
+from govoplan_calendar.backend.service import CalendarError, create_calendar, create_event, create_sync_source, sync_source
+from govoplan_core.db.base import Base
+from govoplan_core.tenancy.scope import create_scope_tables
+from govoplan_tenancy.backend.db.models import Tenant
+
+
+class CalendarSyncSourceTests(unittest.TestCase):
+    def setUp(self) -> None:
+        self.engine = create_engine("sqlite:///:memory:")
+        create_scope_tables(self.engine)
+        Base.metadata.create_all(bind=self.engine)
+        self.Session = sessionmaker(bind=self.engine)
+
+    def tearDown(self) -> None:
+        Base.metadata.drop_all(bind=self.engine)
+
+    def session_with_calendar(self):
+        session = self.Session()
+        session.add(Tenant(id="tenant-1", slug="tenant-1", name="Tenant"))
+        calendar = create_calendar(session, tenant_id="tenant-1", user_id=None, payload=CalendarCollectionCreateRequest(name="Remote"))
+        session.flush()
+        return session, calendar
+
+    def test_ics_subscription_sync_imports_events_and_blocks_local_mutation(self) -> None:
+        session, calendar = self.session_with_calendar()
+        source = create_sync_source(
+            session,
+            tenant_id="tenant-1",
+            user_id=None,
+            payload=CalendarSyncSourceCreateRequest(
+                source_kind="ics",
+                calendar_id=calendar.id,
+                collection_url="https://calendar.example.test/feed.ics",
+                sync_direction="two_way",
+            ),
+        )
+
+        ics = """BEGIN:VCALENDAR
+VERSION:2.0
+BEGIN:VEVENT
+UID:ics-1@example.test
+DTSTART:20260708T090000Z
+DTEND:20260708T100000Z
+SUMMARY:ICS item
+END:VEVENT
+END:VCALENDAR
+"""
+        with patch("govoplan_calendar.backend.service.http_request", return_value=(200, {"etag": '"feed-1"'}, ics)):
+            refreshed, stats = sync_source(session, tenant_id="tenant-1", user_id=None, source_id=source.id)
+
+        event = session.query(CalendarEvent).one()
+        self.assertEqual(refreshed.sync_direction, "inbound")
+        self.assertEqual(stats.created, 1)
+        self.assertEqual(event.source_kind, "ics")
+        self.assertEqual(event.summary, "ICS item")
+        with self.assertRaisesRegex(CalendarError, "inbound-only"):
+            create_event(
+                session,
+                tenant_id="tenant-1",
+                user_id=None,
+                payload=CalendarEventCreateRequest(
+                    calendar_id=calendar.id,
+                    summary="Local edit",
+                    start_at=datetime(2026, 7, 8, 12, tzinfo=timezone.utc),
+                ),
+            )
+
+    def test_graph_sync_imports_delta_events(self) -> None:
+        session, calendar = self.session_with_calendar()
+        source = create_sync_source(
+            session,
+            tenant_id="tenant-1",
+            user_id=None,
+            payload=CalendarSyncSourceCreateRequest(
+                source_kind="graph",
+                calendar_id=calendar.id,
+                collection_url="me/calendar",
+                auth_type="bearer",
+                bearer_token="graph-token",
+            ),
+        )
+        payload = {
+            "value": [
+                {
+                    "id": "graph-event-1",
+                    "iCalUId": "graph-uid-1",
+                    "subject": "Graph item",
+                    "start": {"dateTime": "2026-07-08T09:00:00", "timeZone": "UTC"},
+                    "end": {"dateTime": "2026-07-08T10:00:00", "timeZone": "UTC"},
+                    "@odata.etag": "graph-etag-1",
+                }
+            ],
+            "@odata.deltaLink": "https://graph.microsoft.com/v1.0/me/calendar/events/delta?$deltatoken=next",
+        }
+
+        with patch("govoplan_calendar.backend.service.http_request", return_value=(200, {}, json.dumps(payload))) as request:
+            refreshed, stats = sync_source(session, tenant_id="tenant-1", user_id=None, source_id=source.id)
+
+        event = session.query(CalendarEvent).one()
+        self.assertEqual(stats.created, 1)
+        self.assertEqual(refreshed.sync_token, payload["@odata.deltaLink"])
+        self.assertEqual(event.source_kind, "graph")
+        self.assertEqual(event.source_href, "graph-event-1")
+        self.assertEqual(event.summary, "Graph item")
+        self.assertIn("Bearer graph-token", request.call_args.kwargs["headers"]["Authorization"])
+
+    def test_ews_sync_imports_calendar_view_items(self) -> None:
+        session, calendar = self.session_with_calendar()
+        source = create_sync_source(
+            session,
+            tenant_id="tenant-1",
+            user_id=None,
+            payload=CalendarSyncSourceCreateRequest(
+                source_kind="ews",
+                calendar_id=calendar.id,
+                collection_url="https://exchange.example.test/EWS/Exchange.asmx",
+                auth_type="basic",
+                username="ada",
+                password="secret",
+            ),
+        )
+        response_xml = """<?xml version="1.0" encoding="utf-8"?>
+<s:Envelope xmlns:s="http://schemas.xmlsoap.org/soap/envelope/"
+  xmlns:m="http://schemas.microsoft.com/exchange/services/2006/messages"
+  xmlns:t="http://schemas.microsoft.com/exchange/services/2006/types">
+  <s:Body>
+    <m:FindItemResponse>
+      <m:ResponseMessages>
+        <m:FindItemResponseMessage ResponseClass="Success">
+          <m:RootFolder>
+            <t:Items>
+              <t:CalendarItem>
+                <t:ItemId Id="ews-event-1" ChangeKey="ews-etag-1" />
+                <t:Subject>EWS item</t:Subject>
+                <t:Start>2026-07-08T09:00:00Z</t:Start>
+                <t:End>2026-07-08T10:00:00Z</t:End>
+                <t:IsAllDayEvent>false</t:IsAllDayEvent>
+                <t:UID>ews-uid-1</t:UID>
+              </t:CalendarItem>
+            </t:Items>
+          </m:RootFolder>
+        </m:FindItemResponseMessage>
+      </m:ResponseMessages>
+    </m:FindItemResponse>
+  </s:Body>
+</s:Envelope>"""
+
+        with patch("govoplan_calendar.backend.service.http_request", return_value=(200, {}, response_xml)) as request:
+            _refreshed, stats = sync_source(session, tenant_id="tenant-1", user_id=None, source_id=source.id)
+
+        event = session.query(CalendarEvent).one()
+        self.assertEqual(stats.created, 1)
+        self.assertEqual(event.source_kind, "ews")
+        self.assertEqual(event.source_href, "ews-event-1")
+        self.assertEqual(event.summary, "EWS item")
+        self.assertTrue(request.call_args.kwargs["body"].startswith("<?xml"))
+
+
+if __name__ == "__main__":
+    unittest.main()

webui/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@govoplan/calendar-webui",
-  "version": "0.1.5",
+  "version": "0.1.7",
   "private": true,
   "type": "module",
   "main": "src/index.ts",
@@ -14,8 +14,8 @@
     "./styles/calendar.css": "./src/styles/calendar.css"
   },
   "peerDependencies": {
-    "@govoplan/core-webui": "^0.1.5",
+    "@govoplan/core-webui": "^0.1.7",
-    "lucide-react": "^0.555.0",
+    "lucide-react": "^1.23.0",
     "react": "^19.0.0",
     "react-dom": "^19.0.0",
     "react-router-dom": "^7.1.1",

webui/src/api/calendar.ts

@@ -55,6 +55,117 @@ export type CalendarEvent = {
 
 export type CalendarCollectionListResponse = { calendars: CalendarCollection[] };
 export type CalendarEventListResponse = { events: CalendarEvent[] };
+export type CalendarDeltaDeletedItem = { id: string; resource_type?: string | null; revision?: string | null; deleted_at?: string | null };
+export type CalendarEventDeltaResponse = {
+  events: CalendarEvent[];
+  deleted: CalendarDeltaDeletedItem[];
+  watermark?: string | null;
+  has_more: boolean;
+  full: boolean;
+};
+
+export type CalendarCalDavAuthType = "none" | "basic" | "bearer";
+export type CalendarCalDavSyncDirection = "inbound" | "two_way";
+export type CalendarCalDavConflictPolicy = "etag" | "overwrite";
+export type CalendarSyncSourceKind = "caldav" | "ics" | "webcal" | "graph" | "ews";
+
+export type CalendarSyncSource = {
+  id: string;
+  tenant_id: string;
+  calendar_id: string;
+  source_kind: CalendarSyncSourceKind;
+  collection_url: string;
+  display_name?: string | null;
+  auth_type: CalendarCalDavAuthType;
+  username?: string | null;
+  credential_ref?: string | null;
+  has_credential: boolean;
+  sync_enabled: boolean;
+  sync_interval_seconds: number;
+  sync_direction: CalendarCalDavSyncDirection;
+  conflict_policy: CalendarCalDavConflictPolicy;
+  sync_token?: string | null;
+  ctag?: string | null;
+  last_attempt_at?: string | null;
+  last_synced_at?: string | null;
+  next_sync_at?: string | null;
+  last_status?: string | null;
+  last_error?: string | null;
+  created_at: string;
+  updated_at: string;
+  metadata?: Record<string, unknown> | null;
+};
+
+export type CalendarCalDavSource = CalendarSyncSource;
+export type CalendarSyncSourceListResponse = { sources: CalendarSyncSource[] };
+export type CalendarCalDavSourceListResponse = { sources: CalendarCalDavSource[] };
+
+export type CalendarCalDavDiscoveryCandidate = {
+  collection_url: string;
+  href: string;
+  display_name?: string | null;
+  color?: string | null;
+  ctag?: string | null;
+  sync_token?: string | null;
+};
+
+export type CalendarCalDavDiscoveryPayload = {
+  url: string;
+  source_id?: string | null;
+  auth_type?: CalendarCalDavAuthType | null;
+  username?: string | null;
+  credential_ref?: string | null;
+  password?: string | null;
+  bearer_token?: string | null;
+};
+
+export type CalendarCalDavDiscoveryResponse = { calendars: CalendarCalDavDiscoveryCandidate[] };
+
+export type CalendarSyncSourceCreatePayload = {
+  source_kind?: CalendarSyncSourceKind;
+  calendar_id: string;
+  collection_url: string;
+  display_name?: string | null;
+  auth_type?: CalendarCalDavAuthType;
+  username?: string | null;
+  credential_ref?: string | null;
+  password?: string | null;
+  bearer_token?: string | null;
+  sync_enabled?: boolean;
+  sync_interval_seconds?: number;
+  sync_direction?: CalendarCalDavSyncDirection;
+  conflict_policy?: CalendarCalDavConflictPolicy;
+  metadata?: Record<string, unknown>;
+};
+
+export type CalendarCalDavSourceCreatePayload = CalendarSyncSourceCreatePayload;
+
+export type CalendarCalDavSourceUpdatePayload = Partial<CalendarCalDavSourceCreatePayload>;
+export type CalendarSyncSourceUpdatePayload = Partial<CalendarSyncSourceCreatePayload>;
+
+export type CalendarSyncSourceSyncPayload = {
+  password?: string | null;
+  bearer_token?: string | null;
+  force_full?: boolean;
+};
+
+export type CalendarCalDavSyncPayload = CalendarSyncSourceSyncPayload;
+
+export type CalendarSyncSourceSyncResponse = {
+  source: CalendarSyncSource;
+  created: number;
+  updated: number;
+  deleted: number;
+  unchanged: number;
+  fetched: number;
+  full_sync: boolean;
+  used_sync_token: boolean;
+  sync_token?: string | null;
+  ctag?: string | null;
+  errors: string[];
+};
+
+export type CalendarCalDavSyncResponse = CalendarSyncSourceSyncResponse;
 
 export type CalendarCollectionCreatePayload = {
   name: string;
@@ -79,17 +190,34 @@ export type CalendarCollectionDeletePayload = {
 
 export type CalendarEventCreatePayload = {
   calendar_id?: string | null;
+  uid?: string | null;
+  recurrence_id?: string | null;
+  sequence?: number;
   summary: string;
   description?: string | null;
   location?: string | null;
-  start_at: string;
-  end_at?: string | null;
-  all_day?: boolean;
-  timezone?: string | null;
   status?: string;
   transparency?: string;
   classification?: string;
+  start_at: string;
+  end_at?: string | null;
+  duration_seconds?: number | null;
+  all_day?: boolean;
+  timezone?: string | null;
+  organizer?: Record<string, unknown> | null;
+  attendees?: Record<string, unknown>[];
   categories?: string[];
+  rrule?: Record<string, unknown> | null;
+  rdate?: Record<string, unknown>[];
+  exdate?: Record<string, unknown>[];
+  reminders?: Record<string, unknown>[];
+  attachments?: Record<string, unknown>[];
+  related_to?: Record<string, unknown>[];
+  source_kind?: string;
+  source_href?: string | null;
+  etag?: string | null;
+  icalendar?: Record<string, unknown>;
+  metadata?: Record<string, unknown>;
 };
 
 export type CalendarEventUpdatePayload = Partial<CalendarEventCreatePayload>;
@@ -110,6 +238,57 @@ export function deleteCalendar(settings: ApiSettings, calendarId: string, payloa
   return apiFetch<void>(settings, `/api/v1/calendar/calendars/${calendarId}`, { method: "DELETE", body: JSON.stringify(payload) });
 }
 
+export function listSyncSources(settings: ApiSettings, params: { calendar_id?: string; source_kind?: CalendarSyncSourceKind } = {}): Promise<CalendarSyncSourceListResponse> {
+  const search = new URLSearchParams();
+  if (params.calendar_id) search.set("calendar_id", params.calendar_id);
+  if (params.source_kind) search.set("source_kind", params.source_kind);
+  const suffix = search.toString() ? `?${search.toString()}` : "";
+  return apiFetch<CalendarSyncSourceListResponse>(settings, `/api/v1/calendar/sync-sources${suffix}`);
+}
+
+export function listCalDavSources(settings: ApiSettings, params: { calendar_id?: string } = {}): Promise<CalendarCalDavSourceListResponse> {
+  const search = new URLSearchParams();
+  if (params.calendar_id) search.set("calendar_id", params.calendar_id);
+  const suffix = search.toString() ? `?${search.toString()}` : "";
+  return apiFetch<CalendarCalDavSourceListResponse>(settings, `/api/v1/calendar/caldav/sources${suffix}`);
+}
+
+export function discoverCalDavCalendars(settings: ApiSettings, payload: CalendarCalDavDiscoveryPayload): Promise<CalendarCalDavDiscoveryResponse> {
+  return apiFetch<CalendarCalDavDiscoveryResponse>(settings, "/api/v1/calendar/caldav/discover", { method: "POST", body: JSON.stringify(payload) });
+}
+
+export function createSyncSource(settings: ApiSettings, payload: CalendarSyncSourceCreatePayload): Promise<CalendarSyncSource> {
+  return apiFetch<CalendarSyncSource>(settings, "/api/v1/calendar/sync-sources", { method: "POST", body: JSON.stringify(payload) });
+}
+
+export function createCalDavSource(settings: ApiSettings, payload: CalendarCalDavSourceCreatePayload): Promise<CalendarCalDavSource> {
+  return apiFetch<CalendarCalDavSource>(settings, "/api/v1/calendar/caldav/sources", { method: "POST", body: JSON.stringify(payload) });
+}
+
+export function updateSyncSource(settings: ApiSettings, sourceId: string, payload: CalendarSyncSourceUpdatePayload): Promise<CalendarSyncSource> {
+  return apiFetch<CalendarSyncSource>(settings, `/api/v1/calendar/sync-sources/${sourceId}`, { method: "PATCH", body: JSON.stringify(payload) });
+}
+
+export function updateCalDavSource(settings: ApiSettings, sourceId: string, payload: CalendarCalDavSourceUpdatePayload): Promise<CalendarCalDavSource> {
+  return apiFetch<CalendarCalDavSource>(settings, `/api/v1/calendar/caldav/sources/${sourceId}`, { method: "PATCH", body: JSON.stringify(payload) });
+}
+
+export function deleteSyncSource(settings: ApiSettings, sourceId: string): Promise<void> {
+  return apiFetch<void>(settings, `/api/v1/calendar/sync-sources/${sourceId}`, { method: "DELETE" });
+}
+
+export function deleteCalDavSource(settings: ApiSettings, sourceId: string): Promise<void> {
+  return apiFetch<void>(settings, `/api/v1/calendar/caldav/sources/${sourceId}`, { method: "DELETE" });
+}
+
+export function syncSyncSource(settings: ApiSettings, sourceId: string, payload: CalendarSyncSourceSyncPayload = {}): Promise<CalendarSyncSourceSyncResponse> {
+  return apiFetch<CalendarSyncSourceSyncResponse>(settings, `/api/v1/calendar/sync-sources/${sourceId}/sync`, { method: "POST", body: JSON.stringify(payload) });
+}
+
+export function syncCalDavSource(settings: ApiSettings, sourceId: string, payload: CalendarCalDavSyncPayload = {}): Promise<CalendarCalDavSyncResponse> {
+  return apiFetch<CalendarCalDavSyncResponse>(settings, `/api/v1/calendar/caldav/sources/${sourceId}/sync`, { method: "POST", body: JSON.stringify(payload) });
+}
+
 export function listCalendarEvents(
   settings: ApiSettings,
   params: { calendar_id?: string; start_at?: string; end_at?: string } = {}
@@ -122,6 +301,20 @@ export function listCalendarEvents(
   return apiFetch<CalendarEventListResponse>(settings, `/api/v1/calendar/events${suffix}`);
 }
 
+export function listCalendarEventsDelta(
+  settings: ApiSettings,
+  params: { calendar_id?: string; start_at?: string; end_at?: string; since?: string | null; limit?: number } = {}
+): Promise<CalendarEventDeltaResponse> {
+  const search = new URLSearchParams();
+  if (params.calendar_id) search.set("calendar_id", params.calendar_id);
+  if (params.start_at) search.set("start_at", params.start_at);
+  if (params.end_at) search.set("end_at", params.end_at);
+  if (params.since) search.set("since", params.since);
+  if (params.limit) search.set("limit", String(params.limit));
+  const suffix = search.toString() ? `?${search.toString()}` : "";
+  return apiFetch<CalendarEventDeltaResponse>(settings, `/api/v1/calendar/events/delta${suffix}`);
+}
+
 export function createCalendarEvent(settings: ApiSettings, payload: CalendarEventCreatePayload): Promise<CalendarEvent> {
   return apiFetch<CalendarEvent>(settings, "/api/v1/calendar/events", { method: "POST", body: JSON.stringify(payload) });
 }

webui/src/i18n/generatedTranslations.ts

@@ -0,0 +1,358 @@
+import type { PlatformTranslations } from "@govoplan/core-webui";
+
+export const generatedTranslations: PlatformTranslations = {
+  "en": {
+    "i18n:govoplan-calendar.add_calendar.124c55eb": "Add calendar...",
+    "i18n:govoplan-calendar.add_calendar.8fadb5bc": "Add calendar",
+    "i18n:govoplan-calendar.add.61cc55aa": "Add",
+    "i18n:govoplan-calendar.advanced.4d064726": "Advanced",
+    "i18n:govoplan-calendar.agenda.891e9d6d": "Agenda",
+    "i18n:govoplan-calendar.all_day.11457433": "All day",
+    "i18n:govoplan-calendar.attachments_json.d91abf3c": "Attachments JSON",
+    "i18n:govoplan-calendar.attachments.6771ade6": "Attachments",
+    "i18n:govoplan-calendar.attendees_json.aeb487bb": "Attendees JSON",
+    "i18n:govoplan-calendar.attendees.a45a0962": "Attendees",
+    "i18n:govoplan-calendar.authentication.ee1acfa5": "Authentication",
+    "i18n:govoplan-calendar.automatic_sync.084644b2": "Automatic sync",
+    "i18n:govoplan-calendar.basic.aa2c96da": "Basic",
+    "i18n:govoplan-calendar.bearer_token.ffa64bcf": "Bearer token",
+    "i18n:govoplan-calendar.caldav_source.459ed16a": "CalDAV source",
+    "i18n:govoplan-calendar.caldav.64f9720e": "CalDAV",
+    "i18n:govoplan-calendar.calendar_controls.974f4fa1": "Calendar controls",
+    "i18n:govoplan-calendar.calendar_navigation.7ba43cd2": "Calendar navigation",
+    "i18n:govoplan-calendar.calendar_request_failed.ae8a54f4": "Calendar request failed.",
+    "i18n:govoplan-calendar.calendar_source_type.92cdb42f": "Calendar source type",
+    "i18n:govoplan-calendar.calendar_views.9e6b9c2b": "Calendar views",
+    "i18n:govoplan-calendar.calendar.adab5090": "Calendar",
+    "i18n:govoplan-calendar.calendars.94445018": "Calendars",
+    "i18n:govoplan-calendar.cancel.77dfd213": "Cancel",
+    "i18n:govoplan-calendar.cancelled.5587b0af": "CANCELLED",
+    "i18n:govoplan-calendar.categories.6ccb6007": "Categories",
+    "i18n:govoplan-calendar.change_end_time.db66ef4b": "Change end time",
+    "i18n:govoplan-calendar.change_start_time.06eea3d3": "Change start time",
+    "i18n:govoplan-calendar.class.41ff354b": "Class",
+    "i18n:govoplan-calendar.color.1d0c8304": "Color",
+    "i18n:govoplan-calendar.confidential.84c9cc88": "CONFIDENTIAL",
+    "i18n:govoplan-calendar.configured.668c5fff": "Configured",
+    "i18n:govoplan-calendar.confirm_delete.c9f2829e": "Confirm delete",
+    "i18n:govoplan-calendar.confirmed.0542404a": "CONFIRMED",
+    "i18n:govoplan-calendar.conflict_policy.5810e150": "Conflict policy",
+    "i18n:govoplan-calendar.continuous.04f2ccda": "Continuous",
+    "i18n:govoplan-calendar.credential_reference.a7e92de5": "Credential reference",
+    "i18n:govoplan-calendar.credential.8bede3ea": "Credential",
+    "i18n:govoplan-calendar.dav_url.4205e180": "DAV URL",
+    "i18n:govoplan-calendar.day.987b9ced": "Day",
+    "i18n:govoplan-calendar.delete_events_with_this_calendar.cc0e1287": "Delete events with this calendar",
+    "i18n:govoplan-calendar.delete.f6fdbe48": "Delete",
+    "i18n:govoplan-calendar.deleting.2cda36c9": "Deleting",
+    "i18n:govoplan-calendar.description.55f8ebc8": "Description",
+    "i18n:govoplan-calendar.direction.fd8e45ba": "Direction",
+    "i18n:govoplan-calendar.discover.4827ea22": "Discover",
+    "i18n:govoplan-calendar.discovering.1884f689": "Discovering...",
+    "i18n:govoplan-calendar.display_name.c7874aaa": "Display name",
+    "i18n:govoplan-calendar.duration_must_be_greater_than_zero.519292f7": "Duration must be greater than zero.",
+    "i18n:govoplan-calendar.duration_seconds.19d42eeb": "Duration seconds",
+    "i18n:govoplan-calendar.duration.1370004d": "Duration",
+    "i18n:govoplan-calendar.edit_calendar.a47a2a7a": "Edit calendar",
+    "i18n:govoplan-calendar.edit_event.a7028454": "Edit event",
+    "i18n:govoplan-calendar.edit_value.fad75899": "Edit {value0}",
+    "i18n:govoplan-calendar.end_date_and_time_must_be_after_start_date_and_t.daf31831": "End date and time must be after start date and time.",
+    "i18n:govoplan-calendar.end_date_must_be_on_or_after_start_date.a2518865": "End date must be on or after start date.",
+    "i18n:govoplan-calendar.end_date.89d10cd6": "End date",
+    "i18n:govoplan-calendar.end_mode.5a06de37": "End mode",
+    "i18n:govoplan-calendar.end_time.cd7800da": "End time",
+    "i18n:govoplan-calendar.enter_a_secret_now_or_use_an_environment_referen.6db0e6ce": "Enter a secret now or use an environment reference such as",
+    "i18n:govoplan-calendar.etag.11d00f6e": "ETag",
+    "i18n:govoplan-calendar.event": "event",
+    "i18n:govoplan-calendar.event_count_could_not_be_loaded_the_backend_will.163ff055": "Event count could not be loaded. The backend will still apply the selected delete action.",
+    "i18n:govoplan-calendar.events": "events",
+    "i18n:govoplan-calendar.events_are_stored_in_govoplan_and_are_not_synced.3660e504": "Events are stored in GovOPlaN and are not synced to an external calendar source.",
+    "i18n:govoplan-calendar.ews_endpoint.a3273983": "EWS endpoint",
+    "i18n:govoplan-calendar.exchange_web_services_source.53caabf3": "Exchange Web Services source",
+    "i18n:govoplan-calendar.exchange.5b13eac7": "Exchange",
+    "i18n:govoplan-calendar.exdate_json.7d0c538d": "EXDATE JSON",
+    "i18n:govoplan-calendar.fri.bbd6e32e": "Fri",
+    "i18n:govoplan-calendar.full_sync.21b89c76": "Full sync",
+    "i18n:govoplan-calendar.graph_calendar_url.e59607f3": "Graph calendar URL",
+    "i18n:govoplan-calendar.graph.9a7405eb": "Graph",
+    "i18n:govoplan-calendar.icalendar_json.fb6cc33e": "iCalendar JSON",
+    "i18n:govoplan-calendar.icalendar.f388476d": "iCalendar",
+    "i18n:govoplan-calendar.ics_webcal_subscription.03bc0d63": "ICS/webcal subscription",
+    "i18n:govoplan-calendar.ics_webcal.9c55b570": "ICS/webcal",
+    "i18n:govoplan-calendar.identity.7e5a975b": "Identity",
+    "i18n:govoplan-calendar.inbound_only.bf4269b0": "Inbound only",
+    "i18n:govoplan-calendar.interval.011efcd5": "Interval",
+    "i18n:govoplan-calendar.last_attempt.82aee111": "Last attempt",
+    "i18n:govoplan-calendar.last_sync.ef0ef267": "Last sync",
+    "i18n:govoplan-calendar.loading_calendar.7eb8f548": "Loading calendar...",
+    "i18n:govoplan-calendar.loading_event_count.716ad3c2": "Loading event count...",
+    "i18n:govoplan-calendar.local_calendar.ed3f72f8": "Local calendar",
+    "i18n:govoplan-calendar.local.dc99d54d": "Local",
+    "i18n:govoplan-calendar.location.d219c681": "Location",
+    "i18n:govoplan-calendar.make_target_calendar_the_default.10a3977b": "Make target calendar the default",
+    "i18n:govoplan-calendar.managing_sync_sources_requires_calendar_administ.835e29fa": "Managing sync sources requires calendar administration rights.",
+    "i18n:govoplan-calendar.metadata_json.b0e4c283": "Metadata JSON",
+    "i18n:govoplan-calendar.metadata.251edc0e": "Metadata",
+    "i18n:govoplan-calendar.microsoft_graph_source.ec4f1383": "Microsoft Graph source",
+    "i18n:govoplan-calendar.mon.24b2a099": "Mon",
+    "i18n:govoplan-calendar.month.082bc378": "Month",
+    "i18n:govoplan-calendar.move_events_to_another_calendar.830c7b09": "Move events to another calendar",
+    "i18n:govoplan-calendar.name.709a2322": "Name",
+    "i18n:govoplan-calendar.never.80c3052d": "Never",
+    "i18n:govoplan-calendar.new_event.2ef3795c": "New event",
+    "i18n:govoplan-calendar.new.6403f2b7": "New",
+    "i18n:govoplan-calendar.next_sync.88c7af72": "Next sync",
+    "i18n:govoplan-calendar.next.bc981983": "Next",
+    "i18n:govoplan-calendar.no_calendar_collections_found.6453624a": "No calendar collections found.",
+    "i18n:govoplan-calendar.no_calendars.3a7e4a7a": "No calendars",
+    "i18n:govoplan-calendar.no_events.e339ba73": "No events",
+    "i18n:govoplan-calendar.none.6eef6648": "None",
+    "i18n:govoplan-calendar.not_configured.811931bb": "Not configured",
+    "i18n:govoplan-calendar.not_scheduled.9c367369": "Not scheduled",
+    "i18n:govoplan-calendar.not_synced.4c205136": "Not synced",
+    "i18n:govoplan-calendar.opaque.3e1d0194": "OPAQUE",
+    "i18n:govoplan-calendar.organizer_json.3add6f9f": "Organizer JSON",
+    "i18n:govoplan-calendar.organizer.debd1720": "Organizer",
+    "i18n:govoplan-calendar.overwrite_remote.39625e32": "Overwrite remote",
+    "i18n:govoplan-calendar.participants.cd56e083": "Participants",
+    "i18n:govoplan-calendar.password.8be3c943": "Password",
+    "i18n:govoplan-calendar.previous.50f94286": "Previous",
+    "i18n:govoplan-calendar.private.b0b7ba46": "PRIVATE",
+    "i18n:govoplan-calendar.public.d1785ca2": "PUBLIC",
+    "i18n:govoplan-calendar.raw.da433cd4": "Raw",
+    "i18n:govoplan-calendar.rdate_json.5b51fca4": "RDATE JSON",
+    "i18n:govoplan-calendar.recurrence_id.e0b780ba": "Recurrence ID",
+    "i18n:govoplan-calendar.recurrence.f7ad40f5": "Recurrence",
+    "i18n:govoplan-calendar.refresh.56e3badc": "Refresh",
+    "i18n:govoplan-calendar.related_to_json.2d4e8f59": "Related-To JSON",
+    "i18n:govoplan-calendar.related_to.0e7989ff": "Related-To",
+    "i18n:govoplan-calendar.related.917df91e": "Related",
+    "i18n:govoplan-calendar.reminders_json.ca25e08f": "Reminders JSON",
+    "i18n:govoplan-calendar.reminders.ae8c3939": "Reminders",
+    "i18n:govoplan-calendar.remove_local_events_with_this_calendar.fb8831e1": "Remove local events with this calendar",
+    "i18n:govoplan-calendar.remove.e963907d": "Remove",
+    "i18n:govoplan-calendar.removing.b7d2c38b": "Removing",
+    "i18n:govoplan-calendar.replace_password.3f912c9c": "Replace password",
+    "i18n:govoplan-calendar.replace_token.bbeee6a9": "Replace token",
+    "i18n:govoplan-calendar.require_matching_etag.0ab1ffe1": "Require matching ETag",
+    "i18n:govoplan-calendar.rrule.c7b2f8a3": "RRULE",
+    "i18n:govoplan-calendar.sat.6b782d41": "Sat",
+    "i18n:govoplan-calendar.save.efc007a3": "Save",
+    "i18n:govoplan-calendar.saving.ae7e8875": "Saving...",
+    "i18n:govoplan-calendar.sequence.5c8f4e0e": "Sequence",
+    "i18n:govoplan-calendar.show_value.60e2ce8e": "Show {value0}",
+    "i18n:govoplan-calendar.source_href.819fa147": "Source href",
+    "i18n:govoplan-calendar.source_kind.7eda9bc4": "Source kind",
+    "i18n:govoplan-calendar.source.6da13add": "Source",
+    "i18n:govoplan-calendar.start_date.ff99f5b5": "Start date",
+    "i18n:govoplan-calendar.start_time.88d8206d": "Start time",
+    "i18n:govoplan-calendar.state.a7250206": "State",
+    "i18n:govoplan-calendar.status.bae7d5be": "Status",
+    "i18n:govoplan-calendar.subscription_url.b8b6a1a0": "Subscription URL",
+    "i18n:govoplan-calendar.sun.48c98cab": "Sun",
+    "i18n:govoplan-calendar.sync_now.2b7d938e": "Sync now",
+    "i18n:govoplan-calendar.sync_value.72e4ba66": "Sync {value0}",
+    "i18n:govoplan-calendar.syncing_value.ca80b487": "Syncing {value0}",
+    "i18n:govoplan-calendar.syncing.4ae6fa22": "Syncing",
+    "i18n:govoplan-calendar.syncing.e5c7727a": "Syncing...",
+    "i18n:govoplan-calendar.target_calendar.e533fe1d": "Target calendar",
+    "i18n:govoplan-calendar.tentative.d19f9022": "TENTATIVE",
+    "i18n:govoplan-calendar.the_selected_calendar.67caa12f": "the selected calendar",
+    "i18n:govoplan-calendar.thu.3593ccd9": "Thu",
+    "i18n:govoplan-calendar.timezone.d1f7dc89": "Timezone",
+    "i18n:govoplan-calendar.title.768e0c1c": "Title",
+    "i18n:govoplan-calendar.today.24345a14": "Today",
+    "i18n:govoplan-calendar.transparency.7cb338a9": "Transparency",
+    "i18n:govoplan-calendar.transparent.ea4efcae": "TRANSPARENT",
+    "i18n:govoplan-calendar.tue.529541bb": "Tue",
+    "i18n:govoplan-calendar.two_way.ee50a3e6": "Two-way",
+    "i18n:govoplan-calendar.uid.d946adf5": "UID",
+    "i18n:govoplan-calendar.username.84c29015": "Username",
+    "i18n:govoplan-calendar.value_this_calendar_will_delete_value_value.7869d1f1": "{value0} this calendar will delete {value1} {value2}.",
+    "i18n:govoplan-calendar.value_this_calendar_will_move_value_value_to_val.6c87e1c1": "{value0} this calendar will move {value1} {value2} to {value3}.",
+    "i18n:govoplan-calendar.value_this_calendar_will_remove_value_local_valu.8f21a59e": "{value0} this calendar will remove {value1} local {value2} from GovOPlaN.",
+    "i18n:govoplan-calendar.vevent.9cf5be75": "VEVENT",
+    "i18n:govoplan-calendar.wed.23408b19": "Wed",
+    "i18n:govoplan-calendar.week.f82be68a": "Week",
+    "i18n:govoplan-calendar.whole_day.951c82d1": "Whole day",
+    "i18n:govoplan-calendar.working.049ac820": "Working...",
+    "i18n:govoplan-calendar.workweek.2fef6ea4": "Workweek"
+  },
+  "de": {
+    "i18n:govoplan-calendar.add_calendar.124c55eb": "Add calendar...",
+    "i18n:govoplan-calendar.add_calendar.8fadb5bc": "Add calendar",
+    "i18n:govoplan-calendar.add.61cc55aa": "Hinzufügen",
+    "i18n:govoplan-calendar.advanced.4d064726": "Advanced",
+    "i18n:govoplan-calendar.agenda.891e9d6d": "Agenda",
+    "i18n:govoplan-calendar.all_day.11457433": "Ganztägig",
+    "i18n:govoplan-calendar.attachments_json.d91abf3c": "Attachments JSON",
+    "i18n:govoplan-calendar.attachments.6771ade6": "Attachments",
+    "i18n:govoplan-calendar.attendees_json.aeb487bb": "Attendees JSON",
+    "i18n:govoplan-calendar.attendees.a45a0962": "Attendees",
+    "i18n:govoplan-calendar.authentication.ee1acfa5": "Authentication",
+    "i18n:govoplan-calendar.automatic_sync.084644b2": "Automatic sync",
+    "i18n:govoplan-calendar.basic.aa2c96da": "Basic",
+    "i18n:govoplan-calendar.bearer_token.ffa64bcf": "Bearer token",
+    "i18n:govoplan-calendar.caldav_source.459ed16a": "CalDAV source",
+    "i18n:govoplan-calendar.caldav.64f9720e": "CalDAV",
+    "i18n:govoplan-calendar.calendar_controls.974f4fa1": "Calendar controls",
+    "i18n:govoplan-calendar.calendar_navigation.7ba43cd2": "Calendar navigation",
+    "i18n:govoplan-calendar.calendar_request_failed.ae8a54f4": "Calendar request failed.",
+    "i18n:govoplan-calendar.calendar_source_type.92cdb42f": "Calendar source type",
+    "i18n:govoplan-calendar.calendar_views.9e6b9c2b": "Calendar views",
+    "i18n:govoplan-calendar.calendar.adab5090": "Kalender",
+    "i18n:govoplan-calendar.calendars.94445018": "Calendars",
+    "i18n:govoplan-calendar.cancel.77dfd213": "Abbrechen",
+    "i18n:govoplan-calendar.cancelled.5587b0af": "CANCELLED",
+    "i18n:govoplan-calendar.categories.6ccb6007": "Categories",
+    "i18n:govoplan-calendar.change_end_time.db66ef4b": "Change end time",
+    "i18n:govoplan-calendar.change_start_time.06eea3d3": "Change start time",
+    "i18n:govoplan-calendar.class.41ff354b": "Class",
+    "i18n:govoplan-calendar.color.1d0c8304": "Color",
+    "i18n:govoplan-calendar.confidential.84c9cc88": "CONFIDENTIAL",
+    "i18n:govoplan-calendar.configured.668c5fff": "Configured",
+    "i18n:govoplan-calendar.confirm_delete.c9f2829e": "Confirm delete",
+    "i18n:govoplan-calendar.confirmed.0542404a": "CONFIRMED",
+    "i18n:govoplan-calendar.conflict_policy.5810e150": "Conflict policy",
+    "i18n:govoplan-calendar.continuous.04f2ccda": "Continuous",
+    "i18n:govoplan-calendar.credential_reference.a7e92de5": "Credential reference",
+    "i18n:govoplan-calendar.credential.8bede3ea": "Credential",
+    "i18n:govoplan-calendar.dav_url.4205e180": "DAV URL",
+    "i18n:govoplan-calendar.day.987b9ced": "Tag",
+    "i18n:govoplan-calendar.delete_events_with_this_calendar.cc0e1287": "Delete events with this calendar",
+    "i18n:govoplan-calendar.delete.f6fdbe48": "Löschen",
+    "i18n:govoplan-calendar.deleting.2cda36c9": "Deleting",
+    "i18n:govoplan-calendar.description.55f8ebc8": "Beschreibung",
+    "i18n:govoplan-calendar.direction.fd8e45ba": "Direction",
+    "i18n:govoplan-calendar.discover.4827ea22": "Discover",
+    "i18n:govoplan-calendar.discovering.1884f689": "Discovering...",
+    "i18n:govoplan-calendar.display_name.c7874aaa": "Anzeigename",
+    "i18n:govoplan-calendar.duration_must_be_greater_than_zero.519292f7": "Duration must be greater than zero.",
+    "i18n:govoplan-calendar.duration_seconds.19d42eeb": "Duration seconds",
+    "i18n:govoplan-calendar.duration.1370004d": "Duration",
+    "i18n:govoplan-calendar.edit_calendar.a47a2a7a": "Edit calendar",
+    "i18n:govoplan-calendar.edit_event.a7028454": "Termin bearbeiten",
+    "i18n:govoplan-calendar.edit_value.fad75899": "Edit {value0}",
+    "i18n:govoplan-calendar.end_date_and_time_must_be_after_start_date_and_t.daf31831": "End date and time must be after start date and time.",
+    "i18n:govoplan-calendar.end_date_must_be_on_or_after_start_date.a2518865": "End date must be on or after start date.",
+    "i18n:govoplan-calendar.end_date.89d10cd6": "End date",
+    "i18n:govoplan-calendar.end_mode.5a06de37": "End mode",
+    "i18n:govoplan-calendar.end_time.cd7800da": "End time",
+    "i18n:govoplan-calendar.enter_a_secret_now_or_use_an_environment_referen.6db0e6ce": "Enter a secret now or use an environment reference such as",
+    "i18n:govoplan-calendar.etag.11d00f6e": "ETag",
+    "i18n:govoplan-calendar.event": "event",
+    "i18n:govoplan-calendar.event_count_could_not_be_loaded_the_backend_will.163ff055": "Event count could not be loaded. The backend will still apply the selected delete action.",
+    "i18n:govoplan-calendar.events": "events",
+    "i18n:govoplan-calendar.events_are_stored_in_govoplan_and_are_not_synced.3660e504": "Events are stored in GovOPlaN and are not synced to an external calendar source.",
+    "i18n:govoplan-calendar.ews_endpoint.a3273983": "EWS endpoint",
+    "i18n:govoplan-calendar.exchange_web_services_source.53caabf3": "Exchange Web Services source",
+    "i18n:govoplan-calendar.exchange.5b13eac7": "Exchange",
+    "i18n:govoplan-calendar.exdate_json.7d0c538d": "EXDATE JSON",
+    "i18n:govoplan-calendar.fri.bbd6e32e": "Fri",
+    "i18n:govoplan-calendar.full_sync.21b89c76": "Full sync",
+    "i18n:govoplan-calendar.graph_calendar_url.e59607f3": "Graph calendar URL",
+    "i18n:govoplan-calendar.graph.9a7405eb": "Graph",
+    "i18n:govoplan-calendar.icalendar_json.fb6cc33e": "iCalendar JSON",
+    "i18n:govoplan-calendar.icalendar.f388476d": "iCalendar",
+    "i18n:govoplan-calendar.ics_webcal_subscription.03bc0d63": "ICS/webcal subscription",
+    "i18n:govoplan-calendar.ics_webcal.9c55b570": "ICS/webcal",
+    "i18n:govoplan-calendar.identity.7e5a975b": "Identity",
+    "i18n:govoplan-calendar.inbound_only.bf4269b0": "Inbound only",
+    "i18n:govoplan-calendar.interval.011efcd5": "Interval",
+    "i18n:govoplan-calendar.last_attempt.82aee111": "Last attempt",
+    "i18n:govoplan-calendar.last_sync.ef0ef267": "Last sync",
+    "i18n:govoplan-calendar.loading_calendar.7eb8f548": "Loading calendar...",
+    "i18n:govoplan-calendar.loading_event_count.716ad3c2": "Loading event count...",
+    "i18n:govoplan-calendar.local_calendar.ed3f72f8": "Local calendar",
+    "i18n:govoplan-calendar.local.dc99d54d": "Local",
+    "i18n:govoplan-calendar.location.d219c681": "Ort",
+    "i18n:govoplan-calendar.make_target_calendar_the_default.10a3977b": "Make target calendar the default",
+    "i18n:govoplan-calendar.managing_sync_sources_requires_calendar_administ.835e29fa": "Managing sync sources requires calendar administration rights.",
+    "i18n:govoplan-calendar.metadata_json.b0e4c283": "Metadata JSON",
+    "i18n:govoplan-calendar.metadata.251edc0e": "Metadata",
+    "i18n:govoplan-calendar.microsoft_graph_source.ec4f1383": "Microsoft Graph source",
+    "i18n:govoplan-calendar.mon.24b2a099": "Mon",
+    "i18n:govoplan-calendar.month.082bc378": "Monat",
+    "i18n:govoplan-calendar.move_events_to_another_calendar.830c7b09": "Move events to another calendar",
+    "i18n:govoplan-calendar.name.709a2322": "Name",
+    "i18n:govoplan-calendar.never.80c3052d": "Never",
+    "i18n:govoplan-calendar.new_event.2ef3795c": "New event",
+    "i18n:govoplan-calendar.new.6403f2b7": "New",
+    "i18n:govoplan-calendar.next_sync.88c7af72": "Next sync",
+    "i18n:govoplan-calendar.next.bc981983": "Weiter",
+    "i18n:govoplan-calendar.no_calendar_collections_found.6453624a": "No calendar collections found.",
+    "i18n:govoplan-calendar.no_calendars.3a7e4a7a": "No calendars",
+    "i18n:govoplan-calendar.no_events.e339ba73": "No events",
+    "i18n:govoplan-calendar.none.6eef6648": "Keine",
+    "i18n:govoplan-calendar.not_configured.811931bb": "Nicht konfiguriert",
+    "i18n:govoplan-calendar.not_scheduled.9c367369": "Not scheduled",
+    "i18n:govoplan-calendar.not_synced.4c205136": "Not synced",
+    "i18n:govoplan-calendar.opaque.3e1d0194": "OPAQUE",
+    "i18n:govoplan-calendar.organizer_json.3add6f9f": "Organizer JSON",
+    "i18n:govoplan-calendar.organizer.debd1720": "Organizer",
+    "i18n:govoplan-calendar.overwrite_remote.39625e32": "Overwrite remote",
+    "i18n:govoplan-calendar.participants.cd56e083": "Participants",
+    "i18n:govoplan-calendar.password.8be3c943": "Passwort",
+    "i18n:govoplan-calendar.previous.50f94286": "Previous",
+    "i18n:govoplan-calendar.private.b0b7ba46": "PRIVATE",
+    "i18n:govoplan-calendar.public.d1785ca2": "PUBLIC",
+    "i18n:govoplan-calendar.raw.da433cd4": "Raw",
+    "i18n:govoplan-calendar.rdate_json.5b51fca4": "RDATE JSON",
+    "i18n:govoplan-calendar.recurrence_id.e0b780ba": "Recurrence ID",
+    "i18n:govoplan-calendar.recurrence.f7ad40f5": "Wiederholung",
+    "i18n:govoplan-calendar.refresh.56e3badc": "Refresh",
+    "i18n:govoplan-calendar.related_to_json.2d4e8f59": "Related-To JSON",
+    "i18n:govoplan-calendar.related_to.0e7989ff": "Related-To",
+    "i18n:govoplan-calendar.related.917df91e": "Related",
+    "i18n:govoplan-calendar.reminders_json.ca25e08f": "Reminders JSON",
+    "i18n:govoplan-calendar.reminders.ae8c3939": "Reminders",
+    "i18n:govoplan-calendar.remove_local_events_with_this_calendar.fb8831e1": "Remove local events with this calendar",
+    "i18n:govoplan-calendar.remove.e963907d": "Remove",
+    "i18n:govoplan-calendar.removing.b7d2c38b": "Removing",
+    "i18n:govoplan-calendar.replace_password.3f912c9c": "Replace password",
+    "i18n:govoplan-calendar.replace_token.bbeee6a9": "Replace token",
+    "i18n:govoplan-calendar.require_matching_etag.0ab1ffe1": "Require matching ETag",
+    "i18n:govoplan-calendar.rrule.c7b2f8a3": "RRULE",
+    "i18n:govoplan-calendar.sat.6b782d41": "Sat",
+    "i18n:govoplan-calendar.save.efc007a3": "Speichern",
+    "i18n:govoplan-calendar.saving.ae7e8875": "Saving...",
+    "i18n:govoplan-calendar.sequence.5c8f4e0e": "Sequence",
+    "i18n:govoplan-calendar.show_value.60e2ce8e": "Show {value0}",
+    "i18n:govoplan-calendar.source_href.819fa147": "Source href",
+    "i18n:govoplan-calendar.source_kind.7eda9bc4": "Source kind",
+    "i18n:govoplan-calendar.source.6da13add": "Quelle",
+    "i18n:govoplan-calendar.start_date.ff99f5b5": "Start date",
+    "i18n:govoplan-calendar.start_time.88d8206d": "Start time",
+    "i18n:govoplan-calendar.state.a7250206": "State",
+    "i18n:govoplan-calendar.status.bae7d5be": "Status",
+    "i18n:govoplan-calendar.subscription_url.b8b6a1a0": "Subscription URL",
+    "i18n:govoplan-calendar.sun.48c98cab": "Sun",
+    "i18n:govoplan-calendar.sync_now.2b7d938e": "Sync now",
+    "i18n:govoplan-calendar.sync_value.72e4ba66": "Sync {value0}",
+    "i18n:govoplan-calendar.syncing_value.ca80b487": "Syncing {value0}",
+    "i18n:govoplan-calendar.syncing.4ae6fa22": "Syncing",
+    "i18n:govoplan-calendar.syncing.e5c7727a": "Syncing...",
+    "i18n:govoplan-calendar.target_calendar.e533fe1d": "Target calendar",
+    "i18n:govoplan-calendar.tentative.d19f9022": "TENTATIVE",
+    "i18n:govoplan-calendar.the_selected_calendar.67caa12f": "the selected calendar",
+    "i18n:govoplan-calendar.thu.3593ccd9": "Thu",
+    "i18n:govoplan-calendar.timezone.d1f7dc89": "Timezone",
+    "i18n:govoplan-calendar.title.768e0c1c": "Title",
+    "i18n:govoplan-calendar.today.24345a14": "Heute",
+    "i18n:govoplan-calendar.transparency.7cb338a9": "Transparency",
+    "i18n:govoplan-calendar.transparent.ea4efcae": "TRANSPARENT",
+    "i18n:govoplan-calendar.tue.529541bb": "Tue",
+    "i18n:govoplan-calendar.two_way.ee50a3e6": "Two-way",
+    "i18n:govoplan-calendar.uid.d946adf5": "UID",
+    "i18n:govoplan-calendar.username.84c29015": "Benutzername",
+    "i18n:govoplan-calendar.value_this_calendar_will_delete_value_value.7869d1f1": "{value0} this calendar will delete {value1} {value2}.",
+    "i18n:govoplan-calendar.value_this_calendar_will_move_value_value_to_val.6c87e1c1": "{value0} this calendar will move {value1} {value2} to {value3}.",
+    "i18n:govoplan-calendar.value_this_calendar_will_remove_value_local_valu.8f21a59e": "{value0} this calendar will remove {value1} local {value2} from GovOPlaN.",
+    "i18n:govoplan-calendar.vevent.9cf5be75": "VEVENT",
+    "i18n:govoplan-calendar.wed.23408b19": "Wed",
+    "i18n:govoplan-calendar.week.f82be68a": "Woche",
+    "i18n:govoplan-calendar.whole_day.951c82d1": "Whole day",
+    "i18n:govoplan-calendar.working.049ac820": "Working...",
+    "i18n:govoplan-calendar.workweek.2fef6ea4": "Workweek"
+  }
+};

webui/src/module.ts

@@ -1,21 +1,27 @@
 import { createElement, lazy } from "react";
 import type { PlatformWebModule } from "@govoplan/core-webui";
 import "./styles/calendar.css";
+import { generatedTranslations } from "./i18n/generatedTranslations";
 
 const CalendarPage = lazy(() => import("./features/calendar/CalendarPage"));
 
 const eventRead = ["calendar:event:read"];
+const translations = {
+  en: generatedTranslations.en,
+  de: generatedTranslations.de
+};
 
 export const calendarModule: PlatformWebModule = {
   id: "calendar",
-  label: "Calendar",
+  label: "i18n:govoplan-calendar.calendar.adab5090",
   version: "1.0.0",
   dependencies: ["access"],
   optionalDependencies: ["mail", "tasks", "scheduling", "appointments", "workflow", "notifications", "dms", "connectors"],
-  navItems: [{ to: "/calendar", label: "Calendar", iconName: "calendar", anyOf: eventRead, order: 55 }],
+  translations,
+  navItems: [{ to: "/calendar", label: "i18n:govoplan-calendar.calendar.adab5090", iconName: "calendar", anyOf: eventRead, order: 55 }],
   routes: [
-    { path: "/calendar", anyOf: eventRead, order: 55, render: ({ settings, auth }) => createElement(CalendarPage, { settings, auth }) }
+  { path: "/calendar", anyOf: eventRead, order: 55, render: ({ settings, auth }) => createElement(CalendarPage, { settings, auth }) }]
-  ]
+
 };
 
-export default calendarModule;
+export default calendarModule;

webui/src/styles/calendar.css

@@ -17,6 +17,11 @@
   box-sizing: border-box;
 }
 
+.calendar-loading-frame {
+  min-height: 0;
+  height: 100%;
+}
+
 .calendar-shell {
   min-height: 0;
   height: 100%;
@@ -101,59 +106,13 @@
 
 .calendar-mode-switch {
   flex: 0 1 520px;
-  display: inline-grid;
   grid-template-columns: repeat(5, minmax(0, 1fr));
   width: min(520px, 100%);
   max-width: 520px;
-  overflow: hidden;
-  border: 1px solid #c9c3b9;
-  border-radius: 8px;
-  background: #c9c3b9;
-  box-shadow: inset 0 1px 0 rgba(255,255,255,.75), 0 1px 1px rgba(0,0,0,.05);
 }
 
-.calendar-mode-tab {
+.calendar-mode-switch .segmented-control-option {
   min-height: 34px;
-  border: 0;
-  border-radius: 0;
-  background: linear-gradient(#ffffff, #f1efeb);
-  color: #4f4a43;
-  cursor: pointer;
-  font: inherit;
-  font-size: 13px;
-  font-weight: 800;
-  box-shadow: inset 0 1px 0 rgba(255,255,255,.75), 0 1px 1px rgba(0,0,0,.05);
-  transition: background .18s ease, box-shadow .18s ease, color .18s ease;
-}
-
-.calendar-mode-tab + .calendar-mode-tab {
-  border-left: 1px solid #c9c3b9;
-}
-
-.calendar-mode-tab:first-child {
-  border-radius: 7px 0 0 7px;
-}
-
-.calendar-mode-tab:last-child {
-  border-radius: 0 7px 7px 0;
-}
-
-.calendar-mode-tab:hover,
-.calendar-mode-tab:focus-visible {
-  background: linear-gradient(#ffffff, #e8e5df);
-  color: #4f4a43;
-  box-shadow: inset 0 1px 0 rgba(255,255,255,.82), 0 2px 5px rgba(0,0,0,.08);
-}
-
-.calendar-mode-tab:focus-visible {
-  outline: 3px solid rgba(82, 130, 177, .22);
-  outline-offset: -1px;
-}
-
-.calendar-mode-tab.is-active {
-  background: var(--line);
-  color: var(--text-strong);
-  box-shadow: inset 0 2px 5px rgba(0,0,0,.12), inset 0 -1px 0 rgba(255,255,255,.45);
 }
 
 .calendar-sidebar {
@@ -216,7 +175,7 @@
 .calendar-list-row {
   min-width: 0;
   display: grid;
-  grid-template-columns: 42px minmax(0, 1fr) 30px;
+  grid-template-columns: 42px minmax(0, 1fr) auto;
   align-items: center;
   gap: 4px;
   min-height: 36px;
@@ -230,6 +189,10 @@
   background: var(--panel-soft);
 }
 
+.calendar-list-row.is-syncing {
+  background: var(--panel-soft);
+}
+
 .calendar-visibility-switch {
   --calendar-list-color: var(--green);
   width: 34px;
@@ -286,6 +249,14 @@
   outline: none;
 }
 
+.calendar-list-actions {
+  display: flex;
+  align-items: center;
+  justify-content: flex-end;
+  gap: 2px;
+  min-width: 28px;
+}
+
 .calendar-row-icon-button.btn {
   width: 28px;
   min-width: 28px;
@@ -306,44 +277,41 @@
   opacity: 1;
 }
 
-.calendar-create-form input[type="color"] {
+.calendar-row-icon-button.btn.is-syncing,
-  width: 24px;
+.calendar-row-icon-button.btn.is-syncing:disabled {
-  min-width: 24px;
+  border-color: var(--green);
-  height: 24px;
+  background: var(--surface);
-  padding: 0;
+  color: var(--green);
-  overflow: hidden;
+  opacity: 1;
-  border: 1px solid var(--line-dark);
+  cursor: progress;
-  border-radius: 4px;
-  background: transparent;
-  cursor: pointer;
 }
 
-.calendar-create-form input:disabled {
+.calendar-sync-spin {
-  opacity: .55;
+  animation: calendar-sync-spin .85s linear infinite;
-  cursor: not-allowed;
 }
 
-.calendar-create-form {
+@keyframes calendar-sync-spin {
+  to {
+    transform: rotate(360deg);
+  }
+}
+
+@media (prefers-reduced-motion: reduce) {
+  .calendar-sync-spin {
+    animation: none;
+  }
+}
+
+.calendar-create-action {
   min-width: 0;
-  display: grid;
-  grid-template-columns: minmax(0, 1fr) 28px 36px;
-  align-items: center;
-  gap: 6px;
   margin-top: 6px;
   padding-top: 8px;
   border-top: 1px solid var(--line);
 }
 
-.calendar-create-form input[type="text"],
+.calendar-create-action .btn {
-.calendar-create-form input:not([type]) {
+  width: 100%;
-  min-width: 0;
+  justify-content: center;
-  height: 34px;
-  border: 1px solid var(--line-dark);
-  border-radius: 4px;
-  background: var(--surface);
-  color: var(--text);
-  font: inherit;
-  padding: 6px 8px;
 }
 
 .calendar-agenda {
@@ -931,7 +899,11 @@
 }
 
 .calendar-event-dialog {
-  width: min(560px, 100%);
+  width: min(680px, 100%);
+}
+
+.calendar-vevent-dialog {
+  width: min(920px, 100%);
 }
 
 .calendar-dialog-form {
@@ -974,14 +946,205 @@
 
 .calendar-dialog-name-color-row {
   display: grid;
-  grid-template-columns: minmax(0, 1fr) 86px;
+  grid-template-columns: minmax(0, 1fr) 142px;
   gap: 12px;
 }
 
-.calendar-dialog-color-label input[type="color"] {
+.calendar-source-switch {
+  grid-template-columns: repeat(auto-fit, minmax(104px, 1fr));
   width: 100%;
+}
+
+.calendar-source-switch .segmented-control-option {
+  min-height: 34px;
+}
+
+.calendar-source-pane {
+  display: grid;
+  gap: 12px;
+  padding: 12px;
+  border: 1px solid var(--line);
+  border-radius: 6px;
+  background: var(--panel-soft);
+}
+
+.calendar-source-pane h3 {
+  margin: 0;
+  color: var(--text-strong);
+  font-size: 14px;
+}
+
+.calendar-source-pane-heading,
+.calendar-sync-actions {
+  display: flex;
+  align-items: center;
+  justify-content: space-between;
+  gap: 10px;
+}
+
+.calendar-dialog-grid-two,
+.calendar-dialog-grid-three,
+.calendar-caldav-setup,
+.calendar-sync-settings {
+  display: grid;
+  grid-template-columns: repeat(2, minmax(0, 1fr));
+  gap: 12px;
+}
+
+.calendar-dialog-grid-three {
+  grid-template-columns: repeat(3, minmax(0, 1fr));
+}
+
+.calendar-dialog-wide {
+  grid-column: 1 / -1;
+}
+
+.calendar-caldav-setup {
+  align-items: end;
+}
+
+.calendar-discovery-actions {
+  grid-column: 1 / -1;
+  display: flex;
+  align-items: center;
+  gap: 10px;
   min-width: 0;
-  padding: 3px;
+}
+
+.calendar-discovery-actions .btn {
+  flex: 0 0 auto;
+}
+
+.calendar-discovery-actions span {
+  min-width: 0;
+  overflow: hidden;
+  color: var(--muted);
+  font-size: 12px;
+  font-weight: 700;
+  text-overflow: ellipsis;
+  white-space: nowrap;
+}
+
+.calendar-discovery-actions.is-readonly {
+  justify-content: flex-start;
+}
+
+.calendar-advanced-settings {
+  display: grid;
+  gap: 12px;
+}
+
+.calendar-advanced-settings summary {
+  width: fit-content;
+  cursor: pointer;
+  color: var(--text-strong);
+  font-size: 13px;
+  font-weight: 800;
+}
+
+.calendar-advanced-settings[open] {
+  gap: 12px;
+}
+
+.calendar-advanced-settings[open] summary {
+  margin-bottom: 12px;
+}
+
+.calendar-vevent-details {
+  border-top: 1px solid var(--line);
+  padding-top: 4px;
+}
+
+.calendar-vevent-section {
+  display: grid;
+  gap: 10px;
+  padding: 12px 0;
+  border-top: 1px solid var(--line);
+}
+
+.calendar-vevent-section:first-of-type {
+  border-top: 0;
+  padding-top: 0;
+}
+
+.calendar-vevent-section h3 {
+  margin: 0;
+  color: var(--text-strong);
+  font-size: 13px;
+}
+
+.calendar-vevent-section textarea {
+  font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", monospace;
+  font-size: 12px;
+  line-height: 1.45;
+}
+
+.calendar-sync-settings {
+  align-items: end;
+}
+
+.calendar-sync-status {
+  padding: 3px 8px;
+  border: 1px solid var(--line-dark);
+  border-radius: 999px;
+  background: var(--surface);
+  color: var(--muted);
+  font-size: 12px;
+  font-weight: 800;
+}
+
+.calendar-sync-status.is-error {
+  border-color: #f0b8b2;
+  background: #fff2f0;
+  color: var(--red);
+}
+
+.calendar-sync-status.is-syncing {
+  border-color: var(--green);
+  background: var(--surface);
+  color: var(--green);
+}
+
+.calendar-sync-button.btn.is-syncing,
+.calendar-sync-button.btn.is-syncing:disabled {
+  opacity: 1;
+  cursor: progress;
+}
+
+.calendar-sync-status-panel {
+  display: grid;
+  gap: 10px;
+  padding: 10px;
+  border: 1px solid var(--line);
+  border-radius: 6px;
+  background: var(--surface);
+}
+
+.calendar-sync-status-panel dl {
+  display: grid;
+  grid-template-columns: repeat(2, minmax(0, 1fr));
+  gap: 8px 14px;
+  margin: 0;
+}
+
+.calendar-sync-status-panel dl div {
+  min-width: 0;
+}
+
+.calendar-sync-status-panel dt {
+  color: var(--muted);
+  font-size: 11px;
+  font-weight: 800;
+  text-transform: uppercase;
+}
+
+.calendar-sync-status-panel dd {
+  margin: 2px 0 0;
+  overflow: hidden;
+  color: var(--text);
+  font-size: 13px;
+  text-overflow: ellipsis;
+  white-space: nowrap;
 }
 
 .calendar-form-error {
@@ -1056,6 +1219,15 @@
   color: var(--muted);
 }
 
+.calendar-delete-dialog {
+  width: min(520px, 100%);
+}
+
+.calendar-delete-dialog-body {
+  display: grid;
+  gap: 12px;
+}
+
 .calendar-event-dialog-footer {
   justify-content: space-between;
   gap: 12px;
@@ -1114,7 +1286,12 @@
 
   .calendar-dialog-row,
   .calendar-dialog-date-row,
-  .calendar-dialog-name-color-row {
+  .calendar-dialog-name-color-row,
+  .calendar-dialog-grid-two,
+  .calendar-dialog-grid-three,
+  .calendar-caldav-setup,
+  .calendar-sync-settings,
+  .calendar-sync-status-panel dl {
     grid-template-columns: 1fr;
   }
 }