"""dump_kicad_vec.py — 把 KiCad 板的离散几何导成 JSON，供 cmp_vec.py 比对。必须用 KiCad python 跑。

输出（单位一律 mm，KiCad 原生坐标系：y 向下）:
  vias.json   [{x, y, drill, top, bot, net}]
  pads.json   [{x, y, layer, net, ref, pad, drill}]
  tracks.json [{x1, y1, x2, y2, width, layer, net}]
  meta.json   {counts, layers}

用法（KiCad python 路径见 ~/skills_env.md 的 KICAD_PYTHON）:
  D:\\KiCad\\10.0\\bin\\python.exe dump_kicad_vec.py \\
      --board E:\\Kicad_design\\FOO\\FOO.kicad_pcb \\
      --out   E:\\Kicad_design\\FOO\\_migration\\gerber\\kicad_vec
"""
from __future__ import annotations

import argparse
import json
import sys
from pathlib import Path


def main() -> int:
    ap = argparse.ArgumentParser(description="Dump KiCad board discrete geometry to JSON (mm)")
    ap.add_argument("--board", required=True)
    ap.add_argument("--out", required=True)
    args = ap.parse_args()

    try:
        import pcbnew
    except ImportError:
        print("[ERROR] 导不到 pcbnew —— 用 KiCad 自带 python 跑（~\\skills_env.md 的 KICAD_PYTHON）。")
        return 1

    out = Path(args.out)
    out.mkdir(parents=True, exist_ok=True)
    board = pcbnew.LoadBoard(args.board)
    mm = pcbnew.ToMM

    def via_size(v) -> float:
        """KiCad 10 起 PCB_VIA::GetWidth() 必须带层参数，不带会断言中止进程。
        老版本又只接受无参形式，所以两种都试。size 只是给人看的，取不到就算了。"""
        for call in (lambda: v.GetWidth(v.TopLayer()), lambda: v.GetWidth()):
            try:
                return mm(call())
            except Exception:
                continue
        return 0.0

    vias, tracks = [], []
    for t in board.GetTracks():
        if isinstance(t, pcbnew.PCB_VIA):
            vias.append({
                "x": mm(t.GetPosition().x), "y": mm(t.GetPosition().y),
                "drill": mm(t.GetDrill()), "size": via_size(t),
                "top": board.GetLayerName(t.TopLayer()),
                "bot": board.GetLayerName(t.BottomLayer()),
                "net": t.GetNetname(),
            })
        else:
            tracks.append({
                "x1": mm(t.GetStart().x), "y1": mm(t.GetStart().y),
                "x2": mm(t.GetEnd().x), "y2": mm(t.GetEnd().y),
                "width": mm(t.GetWidth()),
                "layer": board.GetLayerName(t.GetLayer()),
                "net": t.GetNetname(),
            })

    pads = []
    for fp in board.GetFootprints():
        ref = fp.GetReference()
        for p in fp.Pads():
            pads.append({
                "x": mm(p.GetPosition().x), "y": mm(p.GetPosition().y),
                "layer": board.GetLayerName(p.GetLayer()),
                "net": p.GetNetname(), "ref": ref, "pad": p.GetNumber(),
                "drill": mm(p.GetDrillSizeX()),
            })

    layers = sorted({t["layer"] for t in tracks})
    for name, data in (("vias", vias), ("tracks", tracks), ("pads", pads)):
        (out / f"{name}.json").write_text(json.dumps(data, ensure_ascii=False), encoding="utf-8")
    (out / "meta.json").write_text(json.dumps({
        "units": "mm", "y_axis": "down (KiCad native)",
        "counts": {"vias": len(vias), "tracks": len(tracks), "pads": len(pads)},
        "copper_layers_with_tracks": layers,
    }, ensure_ascii=False, indent=2), encoding="utf-8")

    print(f"[dump] vias={len(vias)}  tracks={len(tracks)}  pads={len(pads)}  -> {out}")
    print(f"[layers] 有走线的铜层：{', '.join(layers)}")
    print("[next] Altium 侧用 eda-agent 导同名 JSON 到 altium_vec/（格式见 "
          "references\\vector-compare.md），然后跑 cmp_vec.py。")
    return 0


if __name__ == "__main__":
    try:
        sys.stdout.reconfigure(encoding="utf-8")
    except Exception:
        pass
    sys.exit(main())