"""Command line entry point."""

from __future__ import annotations

import argparse
import sys

import numpy as np

from pathlib import Path

from . import __version__, overlay
from .detect import detect_page
from .pdf import SourceType, open_source, page_raster


def _info(args: argparse.Namespace) -> int:
    source = open_source(args.pdf, SourceType(args.type) if args.type else None)
    note = f" (detected {source.detected.value}, overridden)" if source.overridden else ""
    print(f"{source.path.name}: {source.type.value}{note}, {len(source)} pages")
    for i in range(len(source)):
        h, w = page_raster(source, i).shape
        print(f"  p{i + 1:<3} {w}x{h}")
    source.close()
    return 0


def _detect(args: argparse.Namespace) -> int:
    source = open_source(args.pdf, SourceType(args.type) if args.type else None)
    out = Path(args.out)
    out.mkdir(parents=True, exist_ok=True)
    pages = range(len(source)) if args.page is None else [args.page - 1]

    for i in pages:
        gray = page_raster(source, i)
        detection = detect_page(gray)
        staves = [s.staff_height for s in detection.systems if s.staff_height]
        note = f", staff {np.median(staves):.0f}px" if staves else ""
        print(
            f"p{i + 1:<3} skew {detection.skew:+.2f}°  "
            f"{len(detection.systems)} systems{note}"
            f"{'  (no bracket)' if detection.bracketless else ''}"
        )
        for n, system in enumerate(detection.systems, 1):
            print(f"      sys{n}: {system.top}–{system.bottom}  h={system.height}")
        overlay.write(gray, detection, out / f"{source.path.stem}-p{i + 1:02}.png")

    print(f"overlays written to {out}/")
    source.close()
    return 0


def main(argv: list[str] | None = None) -> int:
    parser = argparse.ArgumentParser(
        prog="noteman-slicer",
        description="Cut score PDFs into noteman's slice images and markers.",
    )
    parser.add_argument("--version", action="version", version=__version__)
    sub = parser.add_subparsers(dest="command", required=True)

    info = sub.add_parser("info", help="classify a PDF and report its page rasters")
    info.add_argument("pdf")
    info.add_argument(
        "--type",
        choices=[t.value for t in SourceType],
        help="override source-type detection",
    )
    info.set_defaults(func=_info)

    det = sub.add_parser("detect", help="run detection and write debug overlays")
    det.add_argument("pdf")
    det.add_argument("--out", default="overlays", help="output directory")
    det.add_argument("--page", type=int, help="single 1-based page instead of all")
    det.add_argument("--type", choices=[t.value for t in SourceType])
    det.set_defaults(func=_detect)

    args = parser.parse_args(argv)
    return args.func(args)


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