"""DMS Search / shared-with-me / Bulk Routen — extrahiert aus routes.py (BUG-018)."""

from __future__ import annotations

import uuid

from fastapi import (
    APIRouter,
    Depends,
    HTTPException,
)
from sqlalchemy import select, update
from sqlalchemy.ext.asyncio import AsyncSession

from app.core.db import get_db
from app.core.visibility import apply_visibility_filter
from app.deps import get_current_user, require_permission
from app.plugins.builtins.dms.common import (
    _parse_uuid,
)
from app.plugins.builtins.dms.models import File as DmsFile
from app.plugins.builtins.dms.models import Folder
from app.plugins.builtins.dms.schemas import BulkDeleteRequest, BulkMoveRequest
from app.plugins.builtins.permissions.contracts import get_contract as get_perms_contract

_perms_contract = get_perms_contract()
Permission = _perms_contract.Permission

router = APIRouter(tags=["dms"])

@router.get("/search", dependencies=[Depends(require_permission("dms:read"))])
async def search_files(
    q: str,
    db: AsyncSession = Depends(get_db),
    current_user: dict = Depends(get_current_user),
):
    """AC16: GET /api/v1/dms/search?q=text → 200 + matching files (ILIKE)."""
    tenant_id = uuid.UUID(current_user["tenant_id"])
    user_id = uuid.UUID(current_user["user_id"])
    is_system_admin = current_user.get("role") == "admin"

    query = select(DmsFile).where(
        DmsFile.tenant_id == tenant_id,
        DmsFile.deleted_at.is_(None),
        DmsFile.name.ilike(f"%{q}%"),
    )
    query = await apply_visibility_filter(
        db, query, "dms_file", DmsFile, user_id, tenant_id, is_system_admin
    )
    result = await db.execute(query)
    files = result.scalars().all()

    return [
        {
            "id": str(f.id),
            "name": f.name,
            "folder_id": str(f.folder_id) if f.folder_id else None,
            "uploaded_by": str(f.uploaded_by),
            "mime_type": f.mime_type,
            "size_bytes": f.size_bytes,
            "deleted_at": None,
            "created_at": f.created_at.isoformat() if f.created_at else None,
        }
        for f in files
    ]


@router.get("/shared-with-me", dependencies=[Depends(require_permission("dms:read"))])
async def shared_with_me(
    db: AsyncSession = Depends(get_db),
    current_user: dict = Depends(get_current_user),
):
    """AC17: GET /api/v1/dms/shared-with-me → 200 + shared files list."""
    tenant_id = uuid.UUID(current_user["tenant_id"])
    user_id = uuid.UUID(current_user["user_id"])
    is_system_admin = current_user.get("role") == "admin"

    # Query permissions for this user and join with files
    perm_result = await db.execute(
        select(Permission).where(
            Permission.tenant_id == tenant_id,
            Permission.user_id == user_id,
        )
    )
    perms = perm_result.scalars().all()
    file_ids = {p.file_id for p in perms}

    if not file_ids:
        return {"items": [], "total": 0}

    query = select(DmsFile).where(
        DmsFile.tenant_id == tenant_id,
        DmsFile.id.in_(file_ids),
        DmsFile.deleted_at.is_(None),
    )
    query = await apply_visibility_filter(
        db, query, "dms_file", DmsFile, user_id, tenant_id, is_system_admin
    )
    result = await db.execute(query)
    files = result.scalars().all()

    # Map permissions for access_level
    perm_map: dict[uuid.UUID, str] = {}
    for p in perms:
        if p.file_id in file_ids:
            perm_map[p.file_id] = p.access_level

    return [
        {
            "id": str(f.id),
            "name": f.name,
            "folder_id": str(f.folder_id) if f.folder_id else None,
            "uploaded_by": str(f.uploaded_by),
            "mime_type": f.mime_type,
            "size_bytes": f.size_bytes,
            "access_level": perm_map.get(f.id, "read"),
            "created_at": f.created_at.isoformat() if f.created_at else None,
        }
        for f in files
    ]


@router.post("/files/bulk-move", dependencies=[Depends(require_permission("dms:write"))])
async def bulk_move(
    body: BulkMoveRequest,
    db: AsyncSession = Depends(get_db),
    current_user: dict = Depends(get_current_user),
):
    """AC18: POST /api/v1/dms/files/bulk-move → 200, files moved."""
    tenant_id = uuid.UUID(current_user["tenant_id"])
    user_id = uuid.UUID(current_user["user_id"])
    is_system_admin = current_user.get("role") == "admin"
    target_folder_id = (
        _parse_uuid(body.target_folder_id, "target_folder_id") if body.target_folder_id else None
    )

    # Validate target folder if specified
    if target_folder_id is not None:
        folder_result = await db.execute(
            select(Folder).where(
                Folder.id == target_folder_id,
                Folder.tenant_id == tenant_id,
                Folder.deleted_at.is_(None),
            )
        )
        if folder_result.scalar_one_or_none() is None:
            raise HTTPException(
                404, detail={"detail": "Target folder not found", "code": "not_found"}
            )

    file_ids = [_parse_uuid(fid, "file_id") for fid in body.file_ids]

    query = select(DmsFile).where(
        DmsFile.tenant_id == tenant_id,
        DmsFile.id.in_(file_ids),
        DmsFile.deleted_at.is_(None),
    )
    query = await apply_visibility_filter(
        db, query, "dms_file", DmsFile, user_id, tenant_id, is_system_admin
    )
    result = await db.execute(query)
    files = result.scalars().all()

    moved_count = 0
    for f in files:
        f.folder_id = target_folder_id
        moved_count += 1

    await db.flush()

    return {
        "moved": moved_count,
        "file_ids": [str(fid) for fid in file_ids],
        "target_folder_id": str(target_folder_id) if target_folder_id else None,
    }


@router.post("/files/bulk-delete", dependencies=[Depends(require_permission("dms:delete"))])
async def bulk_delete(
    body: BulkDeleteRequest,
    db: AsyncSession = Depends(get_db),
    current_user: dict = Depends(get_current_user),
):
    """AC19: POST /api/v1/dms/files/bulk-delete → 200, files soft-deleted."""
    tenant_id = uuid.UUID(current_user["tenant_id"])
    user_id = uuid.UUID(current_user["user_id"])
    is_system_admin = current_user.get("role") == "admin"
    file_ids = [_parse_uuid(fid, "file_id") for fid in body.file_ids]

    from datetime import UTC, datetime

    now = datetime.now(UTC)

    # Apply visibility filter to only delete files user has access to
    query = select(DmsFile).where(
        DmsFile.tenant_id == tenant_id,
        DmsFile.id.in_(file_ids),
        DmsFile.deleted_at.is_(None),
    )
    query = await apply_visibility_filter(
        db, query, "dms_file", DmsFile, user_id, tenant_id, is_system_admin
    )
    result = await db.execute(query)
    accessible_files = result.scalars().all()
    accessible_ids = [f.id for f in accessible_files]

    result = await db.execute(
        update(DmsFile)
        .where(
            DmsFile.tenant_id == tenant_id,
            DmsFile.id.in_(accessible_ids),
            DmsFile.deleted_at.is_(None),
        )
        .values(deleted_at=now)
    )

    deleted_count = result.rowcount
    await db.flush()

    return {
        "deleted": deleted_count,
        "file_ids": body.file_ids,
    }