"""
pipeline/utils.py
Shared utilities: data classes, logger, shell runner, ffprobe wrapper.
Everything else imports from here — no circular deps.
"""

import json
import subprocess
from dataclasses import dataclass
from datetime import datetime
from pathlib import Path
from typing import Any, Dict, List


# ─────────────────────────────────────────────
# DATA CLASSES
# ─────────────────────────────────────────────

@dataclass
class Segment:
    """A highlight segment chosen by the LLM."""
    index  : int
    start  : float      # seconds
    end    : float      # seconds
    reason : str
    score  : float = 0.0

    @property
    def duration(self) -> float:
        return self.end - self.start

    def to_dict(self) -> dict:
        return {
            "index" : self.index,
            "start" : self.start,
            "end"   : self.end,
            "reason": self.reason,
            "score" : self.score,
        }


@dataclass
class ReelOutput:
    """A finished reel file with metadata."""
    index     : int
    path      : Path
    segment   : Segment
    file_size : int = 0

    @property
    def filename(self) -> str:
        return self.path.name

    def to_dict(self) -> dict:
        return {
            "index"           : self.index,
            "filename"        : self.filename,
            "start_s"         : self.segment.start,
            "end_s"           : self.segment.end,
            "duration_s"      : round(self.segment.duration, 2),
            "reason"          : self.segment.reason,
            "score"           : self.segment.score,
            "file_size_bytes" : self.file_size,
        }


# ─────────────────────────────────────────────
# LOGGER
# ─────────────────────────────────────────────

def log(emoji: str, msg: str):
    ts = datetime.now().strftime("%H:%M:%S")
    print(f"[{ts}] {emoji}  {msg}", flush=True)


# ─────────────────────────────────────────────
# SHELL RUNNER
# ─────────────────────────────────────────────

def run_cmd(cmd: List[str], description: str = "") -> subprocess.CompletedProcess:
    """Run a shell command; raise a clear RuntimeError on failure."""
    if description:
        log("⚙️", description)
    result = subprocess.run(cmd, capture_output=True, text=True)
    if result.returncode != 0:
        raise RuntimeError(
            f"Command failed: {' '.join(cmd)}\n"
            f"stderr: {result.stderr[-1000:]}"
        )
    return result


# ─────────────────────────────────────────────
# FFPROBE
# ─────────────────────────────────────────────

def probe_video(video_path: Path) -> Dict[str, Any]:
    """Return duration, width, height for a video file."""
    cmd = [
        "ffprobe", "-v", "quiet",
        "-print_format", "json",
        "-show_format", "-show_streams",
        str(video_path),
    ]
    result = run_cmd(cmd)
    data   = json.loads(result.stdout)
    fmt    = data.get("format", {})
    vstream = next(
        (s for s in data.get("streams", []) if s.get("codec_type") == "video"),
        {},
    )
    return {
        "duration": float(fmt.get("duration", 0)),
        "width"   : int(vstream.get("width",  0)),
        "height"  : int(vstream.get("height", 0)),
        "fps"     : vstream.get("r_frame_rate", "30/1"),
    }


def format_duration(seconds: float) -> str:
    m, s = divmod(int(seconds), 60)
    return f"{m:02d}:{s:02d}"