import { useEffect, useMemo, useRef, useState } from "react";
import { Pencil, Plus, Search, Trash2 } from "lucide-react";
import type { ApiSettings } from "@govoplan/core-webui";
import {
  createSystemRole,
  deleteSystemRole,
  fetchPermissionCatalog,
  fetchSystemRolesDelta,
  updateSystemRole,
  type PermissionItem,
  type RoleSummary } from
"../../api/admin";
import { Button } from "@govoplan/core-webui";
import { ConfirmDialog } from "@govoplan/core-webui";
import { DataGrid, type DataGridColumn } from "@govoplan/core-webui";
import { Dialog } from "@govoplan/core-webui";
import { FormField } from "@govoplan/core-webui";
import { StatusBadge } from "@govoplan/core-webui";
import { AdminIconButton, AdminPageLayout, AdminSelectionList, adminErrorMessage, joinLabels, i18nMessage, useDeltaWatermarks, useUnsavedDraftGuard } from "@govoplan/core-webui";
import { loadDeltaRows } from "./utils/deltaRows";

const emptyDraft = {
  slug: "",
  name: "",
  description: "",
  permissions: [] as string[],
  isAssignable: true
};

export default function SystemRolesPanel({
  settings,
  canWrite,
  onAuthRefresh




}: {settings: ApiSettings;canWrite: boolean;onAuthRefresh: () => Promise<void>;}) {
  const [roles, setRoles] = useState<RoleSummary[]>([]);
  const [permissions, setPermissions] = useState<PermissionItem[]>([]);
  const rolesRef = useRef<RoleSummary[]>([]);
  const { getDeltaWatermark, setDeltaWatermark, resetDeltaWatermark } = useDeltaWatermarks();
  const [editing, setEditing] = useState<RoleSummary | "new" | null>(null);
  const [viewing, setViewing] = useState<RoleSummary | null>(null);
  const [deleting, setDeleting] = useState<RoleSummary | null>(null);
  const [draft, setDraft] = useState(emptyDraft);
  const [savedDraftKey, setSavedDraftKey] = useState(draftKey(emptyDraft));
  const [loading, setLoading] = useState(true);
  const [busy, setBusy] = useState(false);
  const [error, setError] = useState("");
  const [success, setSuccess] = useState("");
  const dirty = editing !== null && draftKey(draft) !== savedDraftKey;

  useUnsavedDraftGuard({
    dirty,
    onSave: save,
    onDiscard: closeEditor
  });

  async function load() {
    setLoading(true);
    setError("");
    try {
      const [nextRoles, catalogue] = await Promise.all([
      loadDeltaRows(rolesRef.current, "access:system-roles", getDeltaWatermark, setDeltaWatermark, (since) => fetchSystemRolesDelta(settings, { since }), (response) => response.roles, (role) => role.id, "access_system_role", sortSystemRoles),
      fetchPermissionCatalog(settings)]
      );
      rolesRef.current = nextRoles;
      setRoles(nextRoles);
      setPermissions(catalogue.filter((item) => item.level === "system"));
    } catch (err) {
      setError(adminErrorMessage(err));
    } finally {
      setLoading(false);
    }
  }

  useEffect(() => {
    rolesRef.current = [];
    resetDeltaWatermark();
    void load();
  }, [settings.accessToken, settings.apiBaseUrl, resetDeltaWatermark]);

  function openCreate() {
    setDraft(emptyDraft);
    setSavedDraftKey(draftKey(emptyDraft));
    setEditing("new");
  }

  function openEdit(role: RoleSummary) {
    const nextDraft = {
      slug: role.slug,
      name: role.name,
      description: role.description || "",
      permissions: role.permissions,
      isAssignable: role.is_assignable
    };
    setDraft(nextDraft);
    setSavedDraftKey(draftKey(nextDraft));
    setEditing(role);
  }

  function closeEditor() {
    setEditing(null);
    setDraft(emptyDraft);
    setSavedDraftKey(draftKey(emptyDraft));
  }

  async function save(): Promise<boolean> {
    setBusy(true);
    setError("");
    try {
      if (editing === "new") {
        await createSystemRole(settings, {
          slug: draft.slug,
          name: draft.name,
          description: draft.description || null,
          permissions: draft.permissions
        });
        setSuccess(i18nMessage("i18n:govoplan-access.system_role_value_created.9c1a6bc8", { value0: draft.name }));
      } else if (editing) {
        await updateSystemRole(settings, editing.id, {
          name: draft.name,
          description: draft.description || null,
          permissions: draft.permissions,
          is_assignable: draft.isAssignable
        });
        setSuccess(i18nMessage("i18n:govoplan-access.system_role_value_updated.3a3f8862", { value0: draft.name }));
      }
      setEditing(null);
      await load();
      await onAuthRefresh();
      return true;
    } catch (err) {
      setError(adminErrorMessage(err));
      return false;
    } finally {
      setBusy(false);
    }
  }

  async function remove() {
    if (!deleting) return;
    setBusy(true);
    setError("");
    try {
      await deleteSystemRole(settings, deleting.id);
      setSuccess(i18nMessage("i18n:govoplan-access.system_role_value_deleted.7b18a6f8", { value0: deleting.name }));
      setDeleting(null);
      await load();
      await onAuthRefresh();
    } catch (err) {
      setError(adminErrorMessage(err));
    } finally {
      setBusy(false);
    }
  }

  const columns = useMemo<DataGridColumn<RoleSummary>[]>(() => [
  {
    id: "role",
    header: "i18n:govoplan-access.system_role.91762640",
    width: 240,
    minWidth: 180,
    maxWidth: 380,
    resizable: true,
    sticky: "start",
    sortable: true,
    filterable: true,
    value: (row) => `${row.name} ${row.slug}`,
    render: (row) => <div><strong>{row.name}</strong><div className="muted small-note">{row.slug}</div></div>
  },
  {
    id: "description",
    header: "i18n:govoplan-access.description.55f8ebc8",
    width: 360,
    fill: true,
    minWidth: 220,
    maxWidth: 640,
    resizable: true,
    sortable: true,
    filterable: true,
    value: (row) => row.description || "",
    render: (row) => row.description || "—"
  },
  {
    id: "permissions",
    header: "i18n:govoplan-access.permissions.d06d5557",
    width: 120,
    resizable: false,
    sortable: true,
    filterable: true,
    filterType: "integer",
    value: (row) => row.effective_permission_count,
    render: (row) => String(row.effective_permission_count)
  },
  {
    id: "assignable",
    header: "i18n:govoplan-access.assignable.a88debc5",
    width: 120,
    resizable: false,
    sortable: true,
    filterable: true,
    value: (row) => row.is_assignable ? "yes" : "no",
    render: (row) => <StatusBadge status={row.is_assignable ? "active" : "inactive"} label={row.is_assignable ? "i18n:govoplan-access.yes.5397e058" : "i18n:govoplan-access.no.816c52fd"} />
  },
  {
    id: "assignments",
    header: "i18n:govoplan-access.accounts.36bae316",
    width: 110,
    resizable: false,
    sortable: true,
    filterable: true,
    filterType: "integer",
    value: (row) => row.user_assignments
  },
  {
    id: "actions",
    header: "i18n:govoplan-access.actions.c3cd636a",
    width: 150,
    sticky: "end",
    resizable: false,
    align: "right",
    render: (row) => {
      const protectedOwner = row.slug === "system_owner";
      return <div className="admin-icon-actions">
          <AdminIconButton label={i18nMessage("i18n:govoplan-access.inspect_value.9d5d1071", { value0: row.name })} icon={<Search />} onClick={() => setViewing(row)} />
          <AdminIconButton label={i18nMessage("i18n:govoplan-access.edit_value.fad75899", { value0: row.name })} icon={<Pencil />} onClick={() => openEdit(row)} disabled={!canWrite || protectedOwner} />
          <AdminIconButton label={i18nMessage("i18n:govoplan-access.delete_value.4d18989e", { value0: row.name })} icon={<Trash2 />} variant="danger" onClick={() => setDeleting(row)} disabled={!canWrite || protectedOwner || row.user_assignments > 0} />
        </div>;
    }
  }],
  [canWrite]);

  return (
    <>
      <AdminPageLayout
        title="i18n:govoplan-access.system_roles.a9461aa6"
        description="i18n:govoplan-access.instance_wide_role_definitions_system_owner_is_p.a888778d"
        loading={loading}
        error={error}
        success={success}
        actions={<><Button onClick={() => void load()} disabled={loading}>i18n:govoplan-access.reload.cce71553</Button><AdminIconButton label="i18n:govoplan-access.add_system_role.f9ef262b" icon={<Plus />} variant="primary" onClick={openCreate} disabled={!canWrite} /></>}>
        
        <div className="admin-table-surface">
          <DataGrid id="admin-system-role-definitions-v4" rows={roles} columns={columns} initialFit="container" getRowKey={(row) => row.id} emptyText="i18n:govoplan-access.no_system_roles_found.051cf727" />
        </div>
      </AdminPageLayout>

      <Dialog
        open={editing !== null}
        title={editing === "new" ? "i18n:govoplan-access.create_system_role.a1e40b25" : "i18n:govoplan-access.edit_system_role.6ebb7cb0"}
        onClose={() => !busy && setEditing(null)}
        className="admin-dialog admin-dialog-wide"
        footer={<><Button onClick={() => setEditing(null)} disabled={busy}>i18n:govoplan-access.cancel.77dfd213</Button><Button variant="primary" onClick={() => void save()} disabled={busy || !draft.name.trim() || !draft.slug.trim()}>{busy ? "i18n:govoplan-access.saving.56a2285c" : "i18n:govoplan-access.save_role.16fe10d1"}</Button></>}>
        
        <div className="admin-form-grid two-columns">
          <FormField label="i18n:govoplan-access.name.709a2322"><input value={draft.name} onChange={(event) => setDraft({ ...draft, name: event.target.value })} /></FormField>
          <FormField label="i18n:govoplan-access.slug.094da9b9"><input value={draft.slug} disabled={editing !== "new"} onChange={(event) => setDraft({ ...draft, slug: event.target.value })} /></FormField>
          <FormField label="i18n:govoplan-access.assignable.a88debc5"><select value={draft.isAssignable ? "yes" : "no"} onChange={(event) => setDraft({ ...draft, isAssignable: event.target.value === "yes" })}><option value="yes">i18n:govoplan-access.yes.5397e058</option><option value="no">i18n:govoplan-access.no.816c52fd</option></select></FormField>
          <FormField label="i18n:govoplan-access.description.55f8ebc8"><textarea rows={3} value={draft.description} onChange={(event) => setDraft({ ...draft, description: event.target.value })} /></FormField>
        </div>
        <div className="form-field">
          <span className="form-label">i18n:govoplan-access.system_permissions.53ff0ab2</span>
          <AdminSelectionList
            options={permissions.filter((permission) => permission.scope !== "system:*").map((permission) => ({ id: permission.scope, label: permission.label, description: permission.description }))}
            selected={draft.permissions}
            onChange={(next) => setDraft({ ...draft, permissions: next })} />
          
          <p className="muted small-note">i18n:govoplan-access.a_role_may_contain_only_permissions_held_by_the_.a7ee5e45</p>
        </div>
      </Dialog>

      <Dialog open={Boolean(viewing)} title={viewing?.name || "i18n:govoplan-access.system_role_details.3d6a8f15"} onClose={() => setViewing(null)} className="admin-dialog admin-dialog-wide" footer={<Button onClick={() => setViewing(null)}>i18n:govoplan-access.close.bbfa773e</Button>}>
        {viewing && <dl className="admin-details-grid"><div><dt>i18n:govoplan-access.slug.094da9b9</dt><dd>{viewing.slug}</dd></div><div><dt>i18n:govoplan-access.protected.28531336</dt><dd>{viewing.slug === "system_owner" ? "i18n:govoplan-access.yes.5397e058" : "i18n:govoplan-access.no.816c52fd"}</dd></div><div><dt>i18n:govoplan-access.assignable.a88debc5</dt><dd>{viewing.is_assignable ? "i18n:govoplan-access.yes.5397e058" : "i18n:govoplan-access.no.816c52fd"}</dd></div><div><dt>i18n:govoplan-access.account_assignments.f5a91f2a</dt><dd>{viewing.user_assignments}</dd></div><div><dt>i18n:govoplan-access.description.55f8ebc8</dt><dd>{viewing.description || "—"}</dd></div><div><dt>i18n:govoplan-access.effective_permissions.17c0fe8a</dt><dd>{viewing.effective_permission_count}</dd></div><div><dt>i18n:govoplan-access.assigned_scopes.c7b09b12</dt><dd>{viewing.permissions.length ? joinLabels(viewing.permissions.map((name) => ({ name }))) : "—"}</dd></div></dl>}
      </Dialog>

      <ConfirmDialog open={Boolean(deleting)} title="i18n:govoplan-access.delete_system_role.e2d84a56" message={i18nMessage("i18n:govoplan-access.delete_value_the_role_must_have_no_account_assig.020eb657", { value0: deleting?.name })} confirmLabel="i18n:govoplan-access.delete_role.fbf0667e" tone="danger" busy={busy} onCancel={() => setDeleting(null)} onConfirm={() => void remove()} />
    </>);

}

function draftKey(draft: typeof emptyDraft): string {
  return JSON.stringify(draft);
}

function sortSystemRoles(left: RoleSummary, right: RoleSummary): number {
  return left.name.localeCompare(right.name);
}