"""
Extract frames for the 238 hard cases from the CSV.

Strategy:
1. First try to find GIDs in parquet files (fast - reuses existing base64 frames)
2. Fallback: download via yt-dlp + extract with PyAV (16 frames per video)

Output: one JSON file per pair at OUTPUT_DIR/{view_gid}_{pub_gid}.json
JSON format mirrors training data messages format:
{
  "view_gid": "...",
  "pub_gid":  "...",
  "class_name": "...",
  "pred_val": 0,
  "true_val": 1,
  "source": "parquet" | "download",
  "messages": [
    {
      "role": "user",
      "content": [
        {"type": "video", "video": ["<b64_frame>", ...]},
        {"type": "text",  "text": "<metadata_json_str>"},
        {"type": "video", "video": ["<b64_frame>", ...]},
        {"type": "text",  "text": "<metadata_json_str>"}
      ]
    },
    {
      "role": "assistant",
      "content": [{"type": "text", "text": "{\"label\": 1}"}]
    }
  ]
}
"""

import argparse
import base64
import csv
import glob
import io
import json
import os
import subprocess
import sys
import traceback
from pathlib import Path

import pyarrow.parquet as pq
from PIL import Image

# ── config ─────────────────────────────────────────────────────────────────────

CSV_PATH   = "/mnt/bn/bohanzhainas1/jiashuo/code/active_reason/4kw树模型标错case-垂类 - jiashuo_analyzed.csv"
PARQUET_DIR = "/mnt/hdfs/byte_tt_data_cu_vagcp/haogeng.liu/new_policy7w_v2_reformat"
OUTPUT_DIR  = Path("/mlx/users/jiashuo.fan/playground/inference/active_cases/frames_cache")
VIDEO_DIR   = Path("/mnt/bn/bohanzhainas1/jiashuo/tmp/active_cases_videos")
N_FRAMES    = 16   # frames per video


# ── helpers ────────────────────────────────────────────────────────────────────

def load_csv():
    rows = []
    with open(CSV_PATH, encoding="utf-8") as f:
        reader = csv.DictReader(f)
        for row in reader:
            rows.append({
                "view_gid":  str(row["view_gid"]).strip(),
                "pub_gid":   str(row["pub_gid"]).strip(),
                "pred_val":  int(row["pred_val"]),
                "true_val":  int(row["true_val"]),
                "class_name": str(row["class_name"]).strip(),
            })
    return rows


def build_gid_index(parquet_dir: str) -> dict:
    """
    Build a mapping: (view_gid, pub_gid) -> (parquet_file, row_index)
    Scans all parquet files; may take a few minutes for 379 files.
    """
    print(f"Building GID index from {parquet_dir} ...")
    files = sorted(glob.glob(f"{parquet_dir}/*.parquet"))
    index = {}
    for file_idx, pf in enumerate(files):
        if file_idx % 50 == 0:
            print(f"  Scanning file {file_idx}/{len(files)} ...", flush=True)
        try:
            table = pq.read_table(pf, columns=["extra_info"])
            for row_idx in range(len(table)):
                raw = table.slice(row_idx, 1).to_pydict()["extra_info"][0]
                extra = json.loads(raw)
                v_gid = str(extra.get("video1", {}).get("gid", ""))
                p_gid = str(extra.get("video2", {}).get("gid", ""))
                key = (v_gid, p_gid)
                if key not in index:
                    index[key] = (pf, row_idx)
        except Exception as e:
            print(f"  Warning: error reading {pf}: {e}", flush=True)
    print(f"Index built: {len(index)} unique pairs", flush=True)
    return index


def load_from_parquet(pf: str, row_idx: int) -> dict:
    """Load the full row (messages + extra_info) from parquet."""
    table = pq.read_table(pf, columns=["messages", "extra_info"])
    row = table.slice(row_idx, 1).to_pydict()
    msgs  = json.loads(row["messages"][0])
    extra = json.loads(row["extra_info"][0])
    return msgs, extra


# ── video download & frame extraction ─────────────────────────────────────────

def download_video(gid: str, out_path: Path) -> bool:
    if out_path.exists() and out_path.stat().st_size > 10_000:
        return True
    out_path.parent.mkdir(parents=True, exist_ok=True)
    url = f"https://www.tiktok.com/@any/video/{gid}"
    cmd = [
        "yt-dlp", "-f", "bestvideo+bestaudio/best",
        "--merge-output-format", "mp4",
        "-o", str(out_path),
        "--no-playlist", "--quiet", "--no-warnings",
        url,
    ]
    try:
        subprocess.run(cmd, capture_output=True, text=True, timeout=120, check=False)
    except subprocess.TimeoutExpired:
        return False
    return out_path.exists() and out_path.stat().st_size > 10_000


def extract_frames_from_video(video_path: Path, n: int = N_FRAMES) -> list[str]:
    """Extract n evenly-spaced frames; return list of base64-encoded JPEG strings."""
    import av
    container = av.open(str(video_path))
    if not container.streams.video:
        container.close()
        return []
    stream = container.streams.video[0]
    total = stream.frames or 0

    if total == 0:
        for _ in container.decode(stream):
            total += 1
        container.seek(0)
        container = av.open(str(video_path))
        stream = container.streams.video[0]

    target_idxs = set(int(i * total / n) for i in range(n))
    b64_frames = []
    frame_idx  = 0
    for frame in container.decode(stream):
        if frame_idx in target_idxs:
            img = frame.to_image().convert("RGB")
            # Resize to max 512px wide to keep size reasonable
            w, h = img.size
            if w > 512:
                img = img.resize((512, int(h * 512 / w)), Image.LANCZOS)
            buf = io.BytesIO()
            img.save(buf, format="JPEG", quality=85)
            b64_frames.append(base64.b64encode(buf.getvalue()).decode())
            if len(b64_frames) >= n:
                break
        frame_idx += 1
    container.close()
    return b64_frames


def make_metadata_text(extra_video: dict) -> str:
    """Build the text metadata JSON string matching training format."""
    return json.dumps({
        "asr":                  extra_video.get("asr", "[]"),
        "key_words":            extra_video.get("key_words", "[]"),
        "mt_diversity_tier3_tags": extra_video.get("mt_diversity_tier3_tags", ""),
        "ocr":                  extra_video.get("ocr", ""),
        "sticker_texts":        extra_video.get("sticker_texts", "[]"),
        "video_caption_v2":     extra_video.get("video_caption_v2", ""),
    }, ensure_ascii=False)


def build_sample_from_parquet(msgs: list, extra: dict, csv_row: dict) -> dict:
    """Use frames from parquet directly; keep original message structure."""
    return {
        "view_gid":  csv_row["view_gid"],
        "pub_gid":   csv_row["pub_gid"],
        "class_name": csv_row["class_name"],
        "pred_val":  csv_row["pred_val"],
        "true_val":  csv_row["true_val"],
        "source":    "parquet",
        "messages":  msgs,
    }


def build_sample_from_download(
    view_b64_frames: list[str],
    pub_b64_frames:  list[str],
    csv_row:         dict,
    view_extra:      dict | None = None,
    pub_extra:       dict | None = None,
) -> dict:
    """Build messages structure from freshly downloaded frames (no metadata)."""
    view_meta_text = make_metadata_text(view_extra or {})
    pub_meta_text  = make_metadata_text(pub_extra  or {})

    msgs = [
        {
            "role": "user",
            "content": [
                {"type": "video", "video": view_b64_frames},
                {"type": "text",  "text":  view_meta_text},
                {"type": "video", "video": pub_b64_frames},
                {"type": "text",  "text":  pub_meta_text},
            ],
        },
        {
            "role": "assistant",
            "content": [{"type": "text", "text": json.dumps({"label": csv_row["true_val"]})}],
        },
    ]
    return {
        "view_gid":  csv_row["view_gid"],
        "pub_gid":   csv_row["pub_gid"],
        "class_name": csv_row["class_name"],
        "pred_val":  csv_row["pred_val"],
        "true_val":  csv_row["true_val"],
        "source":    "download",
        "messages":  msgs,
    }


# ── main ───────────────────────────────────────────────────────────────────────

def main():
    parser = argparse.ArgumentParser()
    parser.add_argument("--skip-parquet", action="store_true", default=True,
                        help="Skip parquet search (default=True; the hard-case GIDs are "
                             "likely not in the training parquet). Use --no-skip-parquet "
                             "to force a full scan of 379 parquet files.")
    parser.add_argument("--no-skip-parquet", dest="skip_parquet", action="store_false",
                        help="Force scan of all parquet files for GID matches")
    parser.add_argument("--skip-download", action="store_true",
                        help="Skip download fallback (only use parquet hits)")
    parser.add_argument("--output-dir", default=str(OUTPUT_DIR))
    args = parser.parse_args()

    out_dir = Path(args.output_dir)
    out_dir.mkdir(parents=True, exist_ok=True)

    csv_rows = load_csv()
    print(f"Loaded {len(csv_rows)} rows from CSV", flush=True)

    # Load already-done pairs
    done = set()
    for f in out_dir.glob("*.json"):
        done.add(f.stem)  # stem = "{view_gid}_{pub_gid}"
    if done:
        print(f"Resuming: {len(done)} already extracted", flush=True)

    pending = [r for r in csv_rows if f"{r['view_gid']}_{r['pub_gid']}" not in done]
    print(f"Pending: {len(pending)}", flush=True)

    if not pending:
        print("All done!", flush=True)
        return

    # Build GID index from parquet (unless --skip-parquet)
    gid_index = {}
    if not args.skip_parquet:
        gid_index = build_gid_index(PARQUET_DIR)

    stats = {"parquet": 0, "download": 0, "failed": 0}

    for i, row in enumerate(pending):
        key      = f"{row['view_gid']}_{row['pub_gid']}"
        out_path = out_dir / f"{key}.json"
        print(f"[{i+1}/{len(pending)}] {key} ({row['class_name']})", flush=True)

        sample = None

        # --- Try parquet first ---
        if not args.skip_parquet:
            parquet_key = (row["view_gid"], row["pub_gid"])
            if parquet_key in gid_index:
                pf, row_idx = gid_index[parquet_key]
                try:
                    msgs, extra = load_from_parquet(pf, row_idx)
                    sample = build_sample_from_parquet(msgs, extra, row)
                    stats["parquet"] += 1
                    print(f"  -> parquet hit: {Path(pf).name}[{row_idx}]", flush=True)
                except Exception as e:
                    print(f"  -> parquet load error: {e}", flush=True)

        # --- Fallback: download ---
        if sample is None and not args.skip_download:
            try:
                pair_dir = VIDEO_DIR / key
                pair_dir.mkdir(parents=True, exist_ok=True)
                view_mp4 = pair_dir / f"view_{row['view_gid']}.mp4"
                pub_mp4  = pair_dir / f"pub_{row['pub_gid']}.mp4"

                view_ok = download_video(row["view_gid"], view_mp4)
                pub_ok  = download_video(row["pub_gid"],  pub_mp4)

                if view_ok and pub_ok:
                    view_frames = extract_frames_from_video(view_mp4, N_FRAMES)
                    pub_frames  = extract_frames_from_video(pub_mp4,  N_FRAMES)
                    if view_frames and pub_frames:
                        sample = build_sample_from_download(
                            view_frames, pub_frames, row
                        )
                        stats["download"] += 1
                        print(f"  -> downloaded: {len(view_frames)}+{len(pub_frames)} frames",
                              flush=True)
                    else:
                        print(f"  -> frame extraction failed", flush=True)
                else:
                    print(f"  -> download failed: view={view_ok} pub={pub_ok}", flush=True)
            except Exception as e:
                print(f"  -> download/extract error: {traceback.format_exc()[:300]}", flush=True)

        if sample is None:
            # Save a stub so we know it failed
            sample = {
                "view_gid":  row["view_gid"],
                "pub_gid":   row["pub_gid"],
                "class_name": row["class_name"],
                "pred_val":  row["pred_val"],
                "true_val":  row["true_val"],
                "source":    "failed",
                "messages":  [],
            }
            stats["failed"] += 1
            print(f"  -> FAILED (no frames available)", flush=True)

        out_path.write_text(json.dumps(sample, ensure_ascii=False))

    print(f"\nDone. parquet={stats['parquet']}  download={stats['download']}  "
          f"failed={stats['failed']}")
    print(f"Output: {out_dir}")


if __name__ == "__main__":
    main()