import json
import re
from pathlib import Path
from typing import Optional, Tuple
from config import OUT_ROOT, FRAME_INTERVAL_SEC, MAX_FRAMES, FRAMES_SUBDIR
from video import prepare_dirs, extract_audio_ffmpeg, extract_frames
from transcribe import transcribe
from vision import caption_folder, dump_json
from packager import write_text, write_manifest, make_zip

TITLE_PATTERNS = [
    re.compile(r"\bIn\s+([A-Za-z0-9:'\-&\. ]+)\s*\((20\d{2}|19\d{2})\)", re.IGNORECASE),
]

def infer_title_year(run_dir: Path) -> Tuple[str, str]:
    """
    Return (title, year) if explicitly detectable in explanations.json metadata or transcription text, else ('','').
    Deterministic. No guessing.
    """
    # Try explanations.json → metadata.title/year
    try:
        ej = json.loads((run_dir / "explanations.json").read_text(encoding="utf-8"))
        if isinstance(ej, dict) and "metadata" in ej and isinstance(ej["metadata"], dict):
            t = ej["metadata"].get("title")
            y = ej["metadata"].get("year")
            if t and y:
                return str(t).strip(), str(y).strip()
    except Exception:
        pass

    # Try transcription.txt pattern
    try:
        txt = (run_dir / "transcription.txt").read_text(encoding="utf-8")
        m = TITLE_PATTERNS[0].search(txt)
        if m:
            return m.group(1).strip(), m.group(2)
    except Exception:
        pass

    return "", ""

def process_video(
    video_file: Path,
    interval_sec: Optional[float] = None,
    max_frames: Optional[int] = None,
    movie_title: str = "",
    movie_year: str = "",
) -> Path:
    interval = interval_sec if interval_sec is not None else FRAME_INTERVAL_SEC
    cap_frames = max_frames if max_frames is not None else MAX_FRAMES

    run_dir, frames_dir = prepare_dirs(OUT_ROOT, video_file)

    # 1) Frames
    n = extract_frames(video_file, frames_dir, interval, cap_frames)

    # 2) Audio + ASR
    wav_path = run_dir / "audio.wav"
    extract_audio_ffmpeg(video_file, wav_path)
    transcript = transcribe(wav_path)
    write_text(transcript, run_dir / "transcription.txt")

    # 3) Vision captions per frame
    explanations = caption_folder(frames_dir)
    dump_json(explanations, run_dir / "explanations.json")

    # 4) Manifest with explicit movie metadata if provided or inferred deterministically
    if not movie_title or not movie_year:
        it, iy = infer_title_year(run_dir)
        movie_title = movie_title or it
        movie_year = movie_year or iy

    manifest = {
        "video": str(video_file.name),
        "frames_dir": FRAMES_SUBDIR,
        "num_frames": n,
        "files": [
            "transcription.txt",
            "explanations.json",
            "audio.wav",
        ],
        "interval_sec": float(interval),
    }

    if movie_title:
        manifest["movie"] = movie_title
    if movie_year:
        manifest["year"] = movie_year

    write_manifest(run_dir, manifest)

    # 5) Zip
    zip_path = make_zip(run_dir)
    return zip_path

if __name__ == "__main__":
    import argparse
    ap = argparse.ArgumentParser()
    ap.add_argument("--video", required=True, type=Path)
    ap.add_argument("--interval", type=float, default=FRAME_INTERVAL_SEC)
    ap.add_argument("--max_frames", type=int, default=MAX_FRAMES)
    ap.add_argument("--movie_title", type=str, default="")
    ap.add_argument("--movie_year", type=str, default="")
    args = ap.parse_args()

    z = process_video(
        args.video,
        interval_sec=args.interval,
        max_frames=args.max_frames,
        movie_title=args.movie_title,
        movie_year=args.movie_year,
    )
    print(z)