from __future__ import annotations

from datetime import datetime
from typing import Any, Literal

from pydantic import BaseModel, Field, model_validator


VCardPlanAction = Literal["create", "update", "ignore", "unchanged", "conflict"]
VCardCommitAction = Literal["create", "update", "ignore"]


class VCardBatchFilePayload(BaseModel):
    filename: str = Field(min_length=1, max_length=500)
    content_base64: str = Field(min_length=1, max_length=14_000_000)


class VCardBatchPreviewRequest(BaseModel):
    files: list[VCardBatchFilePayload] = Field(min_length=1, max_length=50)
    duplicate_card_policy: Literal["reject", "first", "last"] = "reject"
    existing_contact_policy: Literal["update", "ignore", "reject"] = "update"


class VCardDuplicateSuggestion(BaseModel):
    contact_id: str
    display_name: str
    reasons: list[str] = Field(default_factory=list)


class VCardBatchPlanItemResponse(BaseModel):
    source_key: str
    source_filename: str
    card_index: int
    action: VCardPlanAction
    allowed_actions: list[VCardCommitAction] = Field(default_factory=list)
    contact_id: str | None = None
    display_name: str | None = None
    changed_fields: list[str] = Field(default_factory=list)
    duplicate_suggestions: list[VCardDuplicateSuggestion] = Field(default_factory=list)
    message: str | None = None


class VCardBatchDiagnosticResponse(BaseModel):
    severity: Literal["info", "warning", "error"]
    code: str
    message: str
    source_filename: str | None = None
    card_index: int | None = None
    field: str | None = None
    details: dict[str, Any] = Field(default_factory=dict)


class VCardBatchProgressResponse(BaseModel):
    total: int
    completed: int
    created: int = 0
    updated: int = 0
    ignored: int = 0
    failed: int = 0


class VCardBatchRunResponse(BaseModel):
    id: str
    address_book_id: str
    status: str
    input_hash: str
    plan_hash: str
    parser_version: str
    execution_mode: Literal["bounded_sync", "persisted_batch"]
    file_count: int
    card_count: int
    statistics: dict[str, int | str] = Field(default_factory=dict)
    diagnostics: list[VCardBatchDiagnosticResponse] = Field(default_factory=list)
    plan: list[VCardBatchPlanItemResponse] = Field(default_factory=list)
    progress: VCardBatchProgressResponse
    can_apply: bool
    can_cancel: bool
    commit_hash: str | None = None
    created_at: datetime
    updated_at: datetime
    applied_at: datetime | None = None


class VCardBatchSelection(BaseModel):
    source_key: str = Field(min_length=1, max_length=1000)
    action: VCardCommitAction


class VCardBatchCommitRequest(BaseModel):
    expected_plan_hash: str = Field(min_length=64, max_length=64)
    selections: list[VCardBatchSelection] = Field(
        default_factory=list, max_length=10_000
    )


class VCardBatchCancelRequest(BaseModel):
    expected_plan_hash: str = Field(min_length=64, max_length=64)
    reason: str = Field(min_length=3, max_length=2000)


class VCardExportRequest(BaseModel):
    scope: Literal["address_book", "address_list", "contacts"] = "address_book"
    address_list_id: str | None = Field(default=None, max_length=36)
    contact_ids: list[str] = Field(default_factory=list, max_length=10_000)
    version: Literal["3.0", "4.0"] = "4.0"

    @model_validator(mode="after")
    def validate_scope(self) -> "VCardExportRequest":
        if self.scope == "address_list" and not self.address_list_id:
            raise ValueError("Address-list export requires address_list_id.")
        if self.scope == "contacts" and not self.contact_ids:
            raise ValueError(
                "Selected-contact export requires at least one contact id."
            )
        if self.scope != "address_list" and self.address_list_id:
            raise ValueError("address_list_id is only valid for address-list export.")
        if self.scope != "contacts" and self.contact_ids:
            raise ValueError("contact_ids are only valid for selected-contact export.")
        if len(set(self.contact_ids)) != len(self.contact_ids):
            raise ValueError("Selected contact ids must be unique.")
        return self


class VCardExportResponse(BaseModel):
    filename: str
    media_type: str = "text/vcard"
    scope: str
    version: str
    ordering: str
    contact_count: int
    content_hash: str
    content: str


__all__ = [
    "VCardBatchCancelRequest",
    "VCardBatchCommitRequest",
    "VCardBatchFilePayload",
    "VCardBatchPreviewRequest",
    "VCardBatchRunResponse",
    "VCardBatchSelection",
    "VCardExportRequest",
    "VCardExportResponse",
]