import subprocess
from pathlib import Path
from PIL import Image
from app.config import THUMBNAIL_DIR

THUMB_SIZE = (400, 400)


def thumbnail_path(media_id: int) -> Path:
    return THUMBNAIL_DIR / f"{media_id}.jpg"


def generate_image_thumbnail(src: Path, dest: Path) -> None:
    with Image.open(src) as img:
        img.thumbnail(THUMB_SIZE)
        img = img.convert("RGB")
        img.save(dest, "JPEG", quality=85)


def generate_video_thumbnail(src: Path, dest: Path) -> None:
    # Extract frame at 10% of duration
    subprocess.run(
        [
            "ffprobe", "-v", "error", "-show_entries", "format=duration",
            "-of", "default=noprint_wrappers=1:nokey=1", str(src),
        ],
        capture_output=True, text=True, check=False,
    )
    subprocess.run(
        [
            "ffmpeg", "-y", "-ss", "00:00:05", "-i", str(src),
            "-vframes", "1", "-vf", f"scale={THUMB_SIZE[0]}:-1",
            str(dest),
        ],
        capture_output=True, check=False,
    )


def get_or_create_thumbnail(media_id: int, abs_path: str, media_type: str) -> Path | None:
    dest = thumbnail_path(media_id)
    if dest.exists():
        return dest
    src = Path(abs_path)
    if not src.exists():
        return None
    try:
        if media_type == "image":
            generate_image_thumbnail(src, dest)
        else:
            generate_video_thumbnail(src, dest)
        return dest if dest.exists() else None
    except Exception:
        return None