"""
Photos API router
"""
from typing import List, Optional, Dict, Any
from datetime import datetime
from pathlib import Path
from fastapi import APIRouter, Depends, HTTPException, Query, Response
from fastapi.responses import FileResponse
from sqlalchemy import select, and_, or_, func
from sqlalchemy.ext.asyncio import AsyncSession
import json
import os
import logging

logger = logging.getLogger(__name__)

from app.database import get_db
from app.models import Photo, Folder, Tag, PhotoTag
from app.schemas.photos import PhotoResponse, PhotoUpdate, PhotoListResponse, BulkAction
from app.config import settings

router = APIRouter()

@router.get("", response_model=PhotoListResponse)
async def list_photos(
    q: Optional[str] = None,
    date_from: Optional[datetime] = None,
    date_to: Optional[datetime] = None,
    folder_id: Optional[str] = None,
    tag_ids: Optional[str] = None,
    media_type: Optional[str] = None,
    rating_min: Optional[int] = Query(None, ge=0, le=5),
    rating_max: Optional[int] = Query(None, ge=0, le=5),
    color_label: Optional[str] = None,
    is_picked: Optional[bool] = None,
    is_rejected: Optional[bool] = None,
    is_trashed: Optional[bool] = False,
    heap_id: Optional[str] = None,
    sort: str = "taken_at",
    order: str = "desc",
    page: int = Query(1, ge=1),
    per_page: int = Query(100, ge=1, le=500),
    db: AsyncSession = Depends(get_db)
):
    """List photos with filters and pagination"""
    
    # Build query
    query = select(Photo)
    
    # Apply filters
    filters = []
    
    # Text search (would use FTS5 in production)
    if q:
        search_pattern = f"%{q}%"
        filters.append(
            or_(
                Photo.filename.ilike(search_pattern),
                Photo.user_title.ilike(search_pattern),
                Photo.user_notes.ilike(search_pattern),
                Photo.exif_json.ilike(search_pattern)
            )
        )
    
    # Date range
    if date_from:
        filters.append(Photo.taken_at >= date_from)
    if date_to:
        filters.append(Photo.taken_at <= date_to)
    
    # Folder filter
    if folder_id:
        filters.append(Photo.folder_id == folder_id)
    
    # Media type filter
    if media_type:
        types = media_type.split(',')
        filters.append(Photo.media_type.in_(types))
    
    # Rating filter
    if rating_min is not None:
        filters.append(Photo.rating >= rating_min)
    if rating_max is not None:
        filters.append(Photo.rating <= rating_max)
    
    # Color label filter
    if color_label:
        if color_label == 'none':
            filters.append(Photo.color_label.is_(None))
        else:
            filters.append(Photo.color_label == color_label)
    
    # Flag filters
    if is_picked is not None:
        filters.append(Photo.is_picked == is_picked)
    if is_rejected is not None:
        filters.append(Photo.is_rejected == is_rejected)
    
    # Trash filter
    filters.append(Photo.is_trashed == is_trashed)
    
    # Apply all filters
    if filters:
        query = query.where(and_(*filters))
    
    # Apply sorting
    sort_column = getattr(Photo, sort, Photo.taken_at)
    if order == "desc":
        query = query.order_by(sort_column.desc())
    else:
        query = query.order_by(sort_column.asc())
    
    # Count total results
    count_query = select(func.count()).select_from(query.subquery())
    total_result = await db.execute(count_query)
    total = total_result.scalar()
    
    # Apply pagination
    offset = (page - 1) * per_page
    query = query.offset(offset).limit(per_page)
    
    # Execute query
    result = await db.execute(query)
    photos = result.scalars().all()
    
    # Convert to response
    return PhotoListResponse(
        photos=[PhotoResponse.from_orm(photo) for photo in photos],
        total=total,
        page=page,
        per_page=per_page,
        pages=(total + per_page - 1) // per_page
    )

@router.get("/{photo_id}", response_model=PhotoResponse)
async def get_photo(
    photo_id: str,
    db: AsyncSession = Depends(get_db)
):
    """Get single photo with full EXIF and tags"""
    result = await db.execute(
        select(Photo).where(Photo.id == photo_id)
    )
    photo = result.scalar_one_or_none()
    
    if not photo:
        raise HTTPException(status_code=404, detail="Photo not found")
    
    return PhotoResponse.from_orm(photo)

@router.get("/{photo_id}/thumb/{size}")
async def get_thumbnail(
    photo_id: str,
    size: str,
    response: Response,
    db: AsyncSession = Depends(get_db)
):
    """Serve thumbnail (with Nginx X-Accel-Redirect support)"""
    if size not in ['small', 'medium', 'large']:
        raise HTTPException(status_code=400, detail="Invalid thumbnail size")
    
    result = await db.execute(
        select(Photo).where(Photo.id == photo_id)
    )
    photo = result.scalar_one_or_none()
    
    if not photo:
        raise HTTPException(status_code=404, detail="Photo not found")
    
    # Check if thumbnail exists, generate if not
    thumb_dir = f"/data/thumbs/{photo_id}"
    thumb_path = f"{thumb_dir}/{size}.webp"
    
    if not os.path.exists(thumb_path):
        # Generate thumbnail on demand
        from app.tasks.thumbs import generate_thumbnails
        generate_thumbnails.delay(photo_id)
        
        # For now, return a placeholder or the original with reduced quality
        if os.path.exists(photo.filepath):
            from PIL import Image
            try:
                os.makedirs(thumb_dir, exist_ok=True)
                img = Image.open(photo.filepath)
                
                # Auto-rotate based on EXIF
                from PIL import ExifTags
                try:
                    for orientation in ExifTags.TAGS.keys():
                        if ExifTags.TAGS[orientation] == 'Orientation':
                            break
                    exif = img._getexif()
                    if exif is not None:
                        orient = exif.get(orientation)
                        if orient == 3:
                            img = img.rotate(180, expand=True)
                        elif orient == 6:
                            img = img.rotate(270, expand=True)
                        elif orient == 8:
                            img = img.rotate(90, expand=True)
                except:
                    pass
                
                # Generate thumbnail size
                sizes = {'small': 150, 'medium': 400, 'large': 800}
                target_size = sizes.get(size, 400)
                img.thumbnail((target_size, target_size), Image.Resampling.LANCZOS)
                
                # Save as WebP
                img.save(thumb_path, 'WEBP', quality=85, optimize=True)
                
            except Exception as e:
                logger.error(f"Error generating thumbnail: {e}")
                raise HTTPException(status_code=404, detail="Could not generate thumbnail")
    
    # Check if we're behind Nginx
    if os.environ.get('USE_X_ACCEL_REDIRECT'):
        # Use Nginx X-Accel-Redirect for better performance
        response.headers['X-Accel-Redirect'] = f'/internal_thumbs/{photo_id}/{size}.webp'
        response.headers['Content-Type'] = 'image/webp'
        return Response()
    else:
        # Direct file serving for development
        return FileResponse(thumb_path, media_type='image/webp')

@router.get("/{photo_id}/original")
async def get_original(
    photo_id: str,
    db: AsyncSession = Depends(get_db)
):
    """Serve original file for download"""
    result = await db.execute(
        select(Photo).where(Photo.id == photo_id)
    )
    photo = result.scalar_one_or_none()
    
    if not photo:
        raise HTTPException(status_code=404, detail="Photo not found")
    
    if not os.path.exists(photo.filepath):
        raise HTTPException(status_code=404, detail="File not found")
    
    return FileResponse(
        photo.filepath,
        filename=photo.filename,
        media_type='application/octet-stream'
    )

@router.patch("/{photo_id}", response_model=PhotoResponse)
async def update_photo(
    photo_id: str,
    update: PhotoUpdate,
    db: AsyncSession = Depends(get_db)
):
    """Update photo metadata"""
    result = await db.execute(
        select(Photo).where(Photo.id == photo_id)
    )
    photo = result.scalar_one_or_none()
    
    if not photo:
        raise HTTPException(status_code=404, detail="Photo not found")
    
    # Apply updates
    update_data = update.dict(exclude_unset=True)
    for field, value in update_data.items():
        setattr(photo, field, value)
    
    await db.commit()
    await db.refresh(photo)
    
    return PhotoResponse.from_orm(photo)

@router.delete("/{photo_id}")
async def trash_photo(
    photo_id: str,
    db: AsyncSession = Depends(get_db)
):
    """Move photo to trash"""
    result = await db.execute(
        select(Photo).where(Photo.id == photo_id)
    )
    photo = result.scalar_one_or_none()
    
    if not photo:
        raise HTTPException(status_code=404, detail="Photo not found")
    
    # Move file to trash directory
    import shutil
    trash_dir = f"{settings.trash.path}/{photo_id}"
    os.makedirs(trash_dir, exist_ok=True)
    
    trash_path = f"{trash_dir}/original{Path(photo.filepath).suffix}"
    
    try:
        shutil.move(photo.filepath, trash_path)
    except Exception as e:
        raise HTTPException(status_code=500, detail=f"Failed to move file: {e}")
    
    # Update database
    photo.is_trashed = True
    photo.trashed_at = datetime.utcnow()
    
    await db.commit()
    
    return {"status": "success", "message": "Photo moved to trash"}

@router.post("/bulk")
async def bulk_action(
    action: BulkAction,
    db: AsyncSession = Depends(get_db)
):
    """Perform bulk actions on multiple photos"""
    # Get photos
    result = await db.execute(
        select(Photo).where(Photo.id.in_(action.ids))
    )
    photos = result.scalars().all()
    
    if not photos:
        raise HTTPException(status_code=404, detail="No photos found")
    
    # Perform action based on type
    if action.action == 'trash':
        for photo in photos:
            photo.is_trashed = True
            photo.trashed_at = datetime.utcnow()
    elif action.action == 'restore':
        for photo in photos:
            photo.is_trashed = False
            photo.trashed_at = None
    elif action.action == 'set_rating':
        for photo in photos:
            photo.rating = action.value
    elif action.action == 'set_color':
        for photo in photos:
            photo.color_label = action.value
    elif action.action == 'pick':
        for photo in photos:
            photo.is_picked = True
            photo.is_rejected = False
    elif action.action == 'reject':
        for photo in photos:
            photo.is_rejected = True
            photo.is_picked = False
    else:
        raise HTTPException(status_code=400, detail="Invalid action")
    
    await db.commit()
    
    return {
        "status": "success",
        "message": f"{action.action} applied to {len(photos)} photos"
    }