import asyncio
from fastapi import APIRouter, Depends, HTTPException, BackgroundTasks
from sqlalchemy.ext.asyncio import AsyncSession
from sqlalchemy import select
from ..dependencies import get_db, get_current_user, require_admin
from ..models.user import User
from ..models.media_item import LibraryItem
from ..services.matcher import match_audiobook, search_for_item, _apply_match, _score_result
from ..services.matching.musicbrainz import get_release_details
from ..services.matching.open_library import get_work_details
from ..services.matching.google_books import search_google_books
from ..services.matching.base import MatchResult
from datetime import datetime

router = APIRouter(prefix="/api/items", tags=["matching"])


@router.post("/{item_id}/match")
async def trigger_match(
    item_id: str,
    background_tasks: BackgroundTasks,
    current_user: User = Depends(get_current_user),
    db: AsyncSession = Depends(get_db),
):
    result = await db.execute(select(LibraryItem).where(LibraryItem.id == item_id))
    item = result.scalar_one_or_none()
    if not item:
        raise HTTPException(status_code=404, detail="Item not found")

    background_tasks.add_task(match_audiobook, item_id)
    return {"message": "Matching gestartet", "itemId": item_id}


@router.get("/{item_id}/match/search")
async def search_match(
    item_id: str,
    q: str | None = None,
    current_user: User = Depends(get_current_user),
    db: AsyncSession = Depends(get_db),
):
    result = await db.execute(select(LibraryItem).where(LibraryItem.id == item_id))
    item = result.scalar_one_or_none()
    if not item:
        raise HTTPException(status_code=404, detail="Item not found")

    query = q or item.title or ""
    author = item.author if not q else None

    results = await search_for_item(query, author)
    return {"results": results}


@router.post("/{item_id}/match/apply")
async def apply_match(
    item_id: str,
    body: dict,
    current_user: User = Depends(get_current_user),
    db: AsyncSession = Depends(get_db),
):
    """
    Wendet einen manuell gewählten Match-Treffer an.
    body: { source, id, title, author, ... }
    """
    result = await db.execute(select(LibraryItem).where(LibraryItem.id == item_id))
    item = result.scalar_one_or_none()
    if not item:
        raise HTTPException(status_code=404, detail="Item not found")

    source = body.get("source", "manual")
    source_id = body.get("id", "")

    # Versuche Details zu laden wenn MusicBrainz/OpenLibrary
    match_result = None
    if source == "musicbrainz":
        match_result = await get_release_details(source_id)
    elif source == "open_library":
        from ..services.matching.open_library import get_work_details
        match_result = await get_work_details(source_id)

    if not match_result:
        # Fallback: nur die übergebenen Daten verwenden
        match_result = MatchResult(
            source=source,
            source_id=source_id,
            title=body.get("title", item.title or ""),
            author=body.get("author"),
            publish_year=body.get("publishYear"),
            cover_url=body.get("cover"),
            confidence=1.0,
        )

    match_result.confidence = 1.0  # Manuell → immer akzeptieren
    await _apply_match(db, item, match_result, confidence=1.0)
    item.match_locked = True
    item.updated_at = datetime.utcnow()
    await db.commit()
    await db.refresh(item)

    from ..routers.items import _enrich_item_with_files
    return await _enrich_item_with_files(item, db)


@router.delete("/{item_id}/match")
async def clear_match(
    item_id: str,
    current_user: User = Depends(get_current_user),
    db: AsyncSession = Depends(get_db),
):
    result = await db.execute(select(LibraryItem).where(LibraryItem.id == item_id))
    item = result.scalar_one_or_none()
    if not item:
        raise HTTPException(status_code=404, detail="Item not found")

    item.matched_source = "none"
    item.matched_id = None
    item.match_confidence = 0.0
    item.match_locked = False
    tags = item.tags or []
    if "zu_prüfen" not in tags:
        tags.append("zu_prüfen")
    item.tags = tags
    item.updated_at = datetime.utcnow()
    await db.commit()
    return {"success": True}