"""Export pipeline stage inputs for a video as a reusable JSON fixture.

Connects to the live database, queries KeyMoments and classification data,
and writes a fixture file that the test harness can consume offline.

Usage:
    python -m pipeline.export_fixture --video-id <uuid> --output fixtures/video.json
    python -m pipeline.export_fixture --video-id <uuid>  # prints to stdout
    python -m pipeline.export_fixture --list              # list available videos

Requires: DATABASE_URL, REDIS_URL environment variables (or .env file).
"""

from __future__ import annotations

import argparse
import json
import sys
import time
from collections import Counter
from pathlib import Path

from sqlalchemy import create_engine, select
from sqlalchemy.orm import Session, sessionmaker


def _log(tag: str, msg: str, level: str = "INFO") -> None:
    """Write structured log line to stderr."""
    print(f"[EXPORT] [{level}] {tag}: {msg}", file=sys.stderr)


def _get_sync_session(database_url: str) -> Session:
    """Create a sync SQLAlchemy session from the database URL."""
    url = database_url.replace("postgresql+asyncpg://", "postgresql+psycopg2://")
    engine = create_engine(url, pool_pre_ping=True)
    factory = sessionmaker(bind=engine)
    return factory()


def _list_videos(database_url: str) -> int:
    """List all videos with their processing status and moment counts."""
    from models import Creator, KeyMoment, SourceVideo

    session = _get_sync_session(database_url)
    try:
        videos = (
            session.execute(
                select(SourceVideo).order_by(SourceVideo.created_at.desc())
            )
            .scalars()
            .all()
        )
        if not videos:
            _log("LIST", "No videos found in database")
            return 0

        print(f"\n{'ID':<38s} {'Status':<14s} {'Moments':>7s}  {'Creator':<20s}  {'Filename'}", file=sys.stderr)
        print(f"{'─'*38} {'─'*14} {'─'*7}  {'─'*20}  {'─'*40}", file=sys.stderr)

        for video in videos:
            moment_count = (
                session.execute(
                    select(KeyMoment.id).where(KeyMoment.source_video_id == video.id)
                )
                .scalars()
                .all()
            )
            creator = session.execute(
                select(Creator).where(Creator.id == video.creator_id)
            ).scalar_one_or_none()
            creator_name = creator.name if creator else "?"

            print(
                f"{str(video.id):<38s} {video.processing_status.value:<14s} "
                f"{len(moment_count):>7d}  {creator_name:<20s}  {video.filename}",
                file=sys.stderr,
            )

        print(f"\nTotal: {len(videos)} videos\n", file=sys.stderr)
        return 0
    finally:
        session.close()


def export_fixture(
    database_url: str,
    redis_url: str,
    video_id: str,
    output_path: str | None = None,
) -> int:
    """Export stage 5 inputs for a video as a JSON fixture.

    Returns exit code: 0 = success, 1 = error.
    """
    from models import Creator, KeyMoment, SourceVideo

    start = time.monotonic()
    _log("CONNECT", "Connecting to database...")

    session = _get_sync_session(database_url)
    try:
        # ── Load video ──────────────────────────────────────────────────
        video = session.execute(
            select(SourceVideo).where(SourceVideo.id == video_id)
        ).scalar_one_or_none()

        if video is None:
            _log("ERROR", f"Video not found: {video_id}", level="ERROR")
            return 1

        creator = session.execute(
            select(Creator).where(Creator.id == video.creator_id)
        ).scalar_one_or_none()
        creator_name = creator.name if creator else "Unknown"

        _log(
            "VIDEO",
            f"Found: {video.filename} by {creator_name} "
            f"({video.duration_seconds or '?'}s, {video.content_type.value}, "
            f"status={video.processing_status.value})",
        )

        # ── Load key moments ────────────────────────────────────────────
        moments = (
            session.execute(
                select(KeyMoment)
                .where(KeyMoment.source_video_id == video_id)
                .order_by(KeyMoment.start_time)
            )
            .scalars()
            .all()
        )

        if not moments:
            _log("ERROR", f"No key moments found for video_id={video_id}", level="ERROR")
            _log("HINT", "Pipeline stages 2-3 must complete before export is possible", level="ERROR")
            return 1

        time_min = min(m.start_time for m in moments)
        time_max = max(m.end_time for m in moments)
        _log("MOMENTS", f"Loaded {len(moments)} key moments (time range: {time_min:.1f}s - {time_max:.1f}s)")

        # ── Load classification data ────────────────────────────────────
        classification_data: list[dict] = []
        cls_source = "missing"

        # Try Redis first
        try:
            import redis as redis_lib

            r = redis_lib.Redis.from_url(redis_url)
            key = f"chrysopedia:classification:{video_id}"
            raw = r.get(key)
            if raw is not None:
                classification_data = json.loads(raw)
                cls_source = "redis"
                ttl = r.ttl(key)
                _log("CLASSIFY", f"Source: redis ({len(classification_data)} entries, TTL={ttl}s)")
        except Exception as exc:
            _log("CLASSIFY", f"Redis unavailable: {exc}", level="WARN")

        # Fallback: check SourceVideo.classification_data column (Phase 2 addition)
        if not classification_data:
            video_cls = getattr(video, "classification_data", None)
            if video_cls:
                classification_data = video_cls
                cls_source = "postgresql"
                _log("CLASSIFY", f"Source: postgresql ({len(classification_data)} entries)")

        if not classification_data:
            _log("CLASSIFY", "No classification data found in Redis or PostgreSQL", level="WARN")
            _log("HINT", "Pipeline stage 4 must complete before classification data is available", level="WARN")
            cls_source = "missing"

        # Build classification lookup by moment_id
        cls_by_moment_id = {c["moment_id"]: c for c in classification_data}

        # Count moments without classification
        unclassified = sum(1 for m in moments if str(m.id) not in cls_by_moment_id)
        if unclassified > 0:
            _log("CLASSIFY", f"WARNING: {unclassified}/{len(moments)} moments have no classification data", level="WARN")

        # ── Build fixture ───────────────────────────────────────────────
        fixture_moments = []
        category_counts: Counter[str] = Counter()

        for m in moments:
            cls_info = cls_by_moment_id.get(str(m.id), {})
            topic_category = cls_info.get("topic_category", "Uncategorized")
            topic_tags = cls_info.get("topic_tags", [])
            category_counts[topic_category] += 1

            fixture_moments.append({
                "moment_id": str(m.id),
                "title": m.title,
                "summary": m.summary,
                "content_type": m.content_type.value,
                "start_time": m.start_time,
                "end_time": m.end_time,
                "plugins": m.plugins or [],
                "raw_transcript": m.raw_transcript or "",
                # Classification data (stage 4 output)
                "classification": {
                    "topic_category": topic_category,
                    "topic_tags": topic_tags,
                },
                # Compatibility fields for existing quality/scorer format
                "transcript_excerpt": (m.raw_transcript or "")[:500],
                "topic_tags": topic_tags,
                "topic_category": topic_category,
            })

        fixture = {
            "video_id": str(video.id),
            "creator_name": creator_name,
            "content_type": video.content_type.value,
            "filename": video.filename,
            "duration_seconds": video.duration_seconds,
            "classification_source": cls_source,
            "export_timestamp": time.strftime("%Y-%m-%dT%H:%M:%SZ", time.gmtime()),
            "moments": fixture_moments,
        }

        fixture_json = json.dumps(fixture, indent=2, ensure_ascii=False)
        fixture_size_kb = len(fixture_json.encode("utf-8")) / 1024

        # ── Output ──────────────────────────────────────────────────────
        if output_path:
            Path(output_path).parent.mkdir(parents=True, exist_ok=True)
            Path(output_path).write_text(fixture_json, encoding="utf-8")
            _log(
                "OUTPUT",
                f"Wrote fixture: {output_path} ({fixture_size_kb:.1f} KB, "
                f"{len(fixture_moments)} moments, {len(category_counts)} categories)",
            )
        else:
            # Print fixture JSON to stdout
            print(fixture_json)
            _log(
                "OUTPUT",
                f"Printed fixture to stdout ({fixture_size_kb:.1f} KB, "
                f"{len(fixture_moments)} moments, {len(category_counts)} categories)",
            )

        # Category breakdown
        for cat, count in category_counts.most_common():
            _log("CATEGORY", f"  {cat}: {count} moments")

        elapsed = time.monotonic() - start
        _log("DONE", f"Export completed in {elapsed:.1f}s")
        return 0

    except Exception as exc:
        _log("ERROR", f"Export failed: {exc}", level="ERROR")
        import traceback
        traceback.print_exc(file=sys.stderr)
        return 1
    finally:
        session.close()


def main() -> int:
    parser = argparse.ArgumentParser(
        prog="pipeline.export_fixture",
        description="Export pipeline stage inputs for a video as a reusable JSON fixture",
    )
    parser.add_argument(
        "--video-id",
        type=str,
        help="UUID of the video to export",
    )
    parser.add_argument(
        "--output", "-o",
        type=str,
        default=None,
        help="Output file path (default: print to stdout)",
    )
    parser.add_argument(
        "--list",
        action="store_true",
        default=False,
        help="List all videos with status and moment counts",
    )

    args = parser.parse_args()

    # Load settings
    from config import get_settings
    settings = get_settings()

    if args.list:
        return _list_videos(settings.database_url)

    if not args.video_id:
        parser.error("--video-id is required (or use --list to see available videos)")

    return export_fixture(
        database_url=settings.database_url,
        redis_url=settings.redis_url,
        video_id=args.video_id,
        output_path=args.output,
    )


if __name__ == "__main__":
    sys.exit(main())