#!/usr/bin/env python3
"""Create one event-centered visual audit sheet per scenario family."""

from __future__ import annotations

import argparse
import json
from pathlib import Path

import cv2
import numpy as np


PROJECT_ROOT = Path(__file__).resolve().parents[2]
DEFAULT_DATASET_ROOT = PROJECT_ROOT / "closed_dataset"
DEFAULT_RUN_ROOT = DEFAULT_DATASET_ROOT / "acceptance_final_v1_runs"
DEFAULT_OUTPUT = DEFAULT_DATASET_ROOT / "acceptance_final_v1/contact_sheets"

PHYSICAL_COMPLETION_EVENTS = {
    "pedestrian_crossing_completed",
    "cut_in_completed",
    "obstacle_reveal_completed",
    "hazard_actor_cleared_route",
    "flow_actor_cleared",
}


def _json_lines(path: Path) -> list[dict]:
    return [
        json.loads(line)
        for line in path.read_text(encoding="utf-8").splitlines()
        if line.strip()
    ]


def _event_frame(run_dir: Path) -> int:
    timeline = _json_lines(run_dir / "event_timeline.jsonl")
    clock = _json_lines(run_dir / "logs/frame_clock.jsonl")
    start = next(item for item in timeline if item.get("event") == "hazard_started")
    completion = next(
        item
        for item in timeline
        if item.get("event") in PHYSICAL_COMPLETION_EVENTS
    )
    target_game_time = (
        float(start["game_time"]) + float(completion["game_time"])
    ) / 2.0
    sim_offset = float(clock[0]["sim_time"])
    target_sim_time = sim_offset + target_game_time
    nearest = min(clock, key=lambda item: abs(float(item["sim_time"]) - target_sim_time))
    return int(nearest["dataset_frame"])


def _read_video_frame(video: Path, frame_index: int) -> np.ndarray:
    capture = cv2.VideoCapture(str(video))
    if not capture.isOpened():
        raise RuntimeError(f"cannot open {video}")
    capture.set(cv2.CAP_PROP_POS_FRAMES, frame_index)
    ok, frame = capture.read()
    capture.release()
    if not ok:
        raise RuntimeError(f"cannot read frame {frame_index} from {video}")
    return frame


def _tile(frame: np.ndarray, title: str, subtitle: str) -> np.ndarray:
    width, height = 384, 216
    frame = cv2.resize(frame, (width, height), interpolation=cv2.INTER_AREA)
    canvas = np.zeros((height + 54, width, 3), dtype=np.uint8)
    canvas[54:] = frame
    cv2.putText(
        canvas,
        title,
        (8, 21),
        cv2.FONT_HERSHEY_SIMPLEX,
        0.52,
        (255, 255, 255),
        1,
        cv2.LINE_AA,
    )
    cv2.putText(
        canvas,
        subtitle,
        (8, 44),
        cv2.FONT_HERSHEY_SIMPLEX,
        0.43,
        (190, 220, 255),
        1,
        cv2.LINE_AA,
    )
    return canvas


def build(dataset_root: Path, run_root: Path, output: Path) -> None:
    manifest = json.loads((dataset_root / "manifest.json").read_text(encoding="utf-8"))
    grouped: dict[str, list[dict]] = {}
    for route in manifest["routes"]:
        grouped.setdefault(route["family"], []).append(route)

    output.mkdir(parents=True, exist_ok=True)
    for family, routes in sorted(grouped.items()):
        tiles = []
        for route in sorted(routes, key=lambda item: item["route_id"]):
            route_id = route["route_id"]
            matches = list(run_root.glob(f"*/{route_id}"))
            if len(matches) != 1:
                raise RuntimeError(f"expected one run directory for {route_id}")
            run_dir = matches[0]
            videos = list((run_dir / "videos").glob("*_pdm_lite_rgb.mp4"))
            if len(videos) != 1:
                raise RuntimeError(f"expected one RGB video for {route_id}")
            frame_index = _event_frame(run_dir)
            frame = _read_video_frame(videos[0], frame_index)
            subtitle = (
                f"{route['town']} | {route['weather_profile'].replace('_', ' ')}"
                f" | event frame {frame_index}"
            )
            tiles.append(_tile(frame, route_id, subtitle))

        rows = [
            np.concatenate(tiles[index : index + 5], axis=1)
            for index in range(0, len(tiles), 5)
        ]
        sheet = np.concatenate(rows, axis=0)
        path = output / f"{family}.jpg"
        if not cv2.imwrite(str(path), sheet, [cv2.IMWRITE_JPEG_QUALITY, 92]):
            raise RuntimeError(f"failed to write {path}")
        print(path)


def main() -> int:
    parser = argparse.ArgumentParser(description=__doc__)
    parser.add_argument("--dataset-root", type=Path, default=DEFAULT_DATASET_ROOT)
    parser.add_argument("--run-root", type=Path, default=DEFAULT_RUN_ROOT)
    parser.add_argument("--output", type=Path, default=DEFAULT_OUTPUT)
    args = parser.parse_args()
    build(args.dataset_root.resolve(), args.run_root.resolve(), args.output.resolve())
    return 0


if __name__ == "__main__":
    raise SystemExit(main())