pcb/scripts/_extract_fixed_routes.py

#!/usr/bin/env python3
"""One-time generator: capture the hand-drawn geometry from route_power_stage.py
and finalize_routing.py into hardware/power_routes.json and
hardware/critical_routes.json, which the project-independent `pcbrouter fixed`
loader consumes.

This is a development tool, not part of the routing flow. It uses pcbnew only to
resolve the pad anchors the scripts reference; the emitted JSON is plain data.
The JSON files are already committed; you only need this to regenerate them after
changing route_power_stage.py / finalize_routing.py.

It reads the intermediate boards board_prerouted.kicad_pcb and
board_power_local.kicad_pcb, which are git-ignored pipeline artifacts. If they
are not present, regenerate them first by running steps 1-4 of scripts/README.md
(preroute_bga -> route_power_stage -> stitch_plane_pads -> route_local_power).

    /usr/bin/python3 scripts/_extract_fixed_routes.py
"""
from __future__ import annotations

import json
from pathlib import Path

import pcbnew

ROOT = Path(__file__).resolve().parents[1]


def mm(v: int) -> float:
    return round(pcbnew.ToMM(v), 4)


class Capture:
    def __init__(self) -> None:
        self.tracks: list[dict] = []
        self.vias: list[dict] = []

    def track(self, net, a, b, width, layer_name):
        if a == b:
            return
        self.tracks.append({
            "net": net, "layer": layer_name, "width": round(width, 4),
            "points": [[round(a[0], 4), round(a[1], 4)], [round(b[0], 4), round(b[1], 4)]],
        })

    def via(self, net, x, y, dia=0.45, drill=0.225):
        self.vias.append({"net": net, "at": [round(x, 4), round(y, 4)],
                          "diameter": round(dia, 4), "drill": round(drill, 4)})

    def as_json(self) -> dict:
        # merge consecutive same-net/same-layer/same-width segments into polylines
        merged: list[dict] = []
        for t in self.tracks:
            if (merged and merged[-1]["net"] == t["net"]
                    and merged[-1]["layer"] == t["layer"]
                    and abs(merged[-1]["width"] - t["width"]) < 1e-6
                    and merged[-1]["points"][-1] == t["points"][0]):
                merged[-1]["points"].append(t["points"][1])
            else:
                merged.append({"net": t["net"], "layer": t["layer"],
                               "width": t["width"], "points": list(t["points"])})
        return {"tracks": merged, "vias": self.vias}


def layer_name(board, layer_id):
    return board.GetLayerName(layer_id)


def patch_power_stage(cap: Capture, board):
    import route_power_stage as rps

    def add_track(b, net, start, end, width, layer=pcbnew.F_Cu):
        cap.track(net, start, end, width, layer_name(board, layer))

    def add_via(b, net, x, y, diameter=0.70, drill=0.35):
        cap.via(net, x, y, diameter, drill)

    rps.add_track = add_track
    rps.add_via = add_via
    rps.add_path = lambda b, net, pts, w, layer=pcbnew.F_Cu: [
        add_track(b, net, s, e, w, layer) for s, e in zip(pts, pts[1:])
    ]


def patch_finalize(cap: Capture, board):
    import finalize_routing as fr

    def add_segment(b, net, start, end, width, layer=pcbnew.F_Cu, locked=True):
        cap.track(net, start, end, width, layer_name(board, layer))

    def add_polyline(b, net, verts, width, layer=pcbnew.F_Cu):
        for s, e in zip(verts, verts[1:]):
            add_segment(b, net, s, e, width, layer)

    def add_via(b, net, position, diameter=0.45, drill=0.225):
        cap.via(net, position[0], position[1], diameter, drill)

    fr.add_segment = add_segment
    fr.add_polyline = add_polyline
    fr.add_via = add_via


def main() -> None:
    for stem in ("board_prerouted", "board_power_local"):
        if not (ROOT / "hardware" / f"{stem}.kicad_pcb").exists():
            raise SystemExit(
                f"hardware/{stem}.kicad_pcb missing - regenerate the pipeline "
                "intermediates first (steps 1-4 of scripts/README.md).")

    # -- power routes -------------------------------------------------------
    board = pcbnew.LoadBoard(str(ROOT / "hardware" / "board_prerouted.kicad_pcb"))
    cap = Capture()
    patch_power_stage(cap, board)
    import route_power_stage as rps
    rps.route_core_buck(board)
    rps.route_small_buck(board, regulator="U14", inductor="L2",
                         input_caps=("C26", "C27"), output_caps=("C28", "C29"),
                         sw_net="BUCK1V8_SW", out_net="VCC1V8",
                         input_x=112.98, plane_via_x=120.105)
    rps.route_small_buck(board, regulator="U15", inductor="L3",
                         input_caps=("C30", "C31"), output_caps=("C32", "C33"),
                         sw_net="BUCK3V3_SW", out_net="VCC3V3",
                         input_x=127.98, plane_via_x=135.105)
    (ROOT / "hardware" / "power_routes.json").write_text(
        json.dumps(cap.as_json(), indent=1) + "\n")
    print(f"power_routes.json: {len(cap.as_json()['tracks'])} polylines, {len(cap.vias)} vias")

    # -- critical (RF / USB) routes + rule areas --------------------------
    board = pcbnew.LoadBoard(str(ROOT / "hardware" / "board_power_local.kicad_pcb"))
    cap = Capture()
    patch_finalize(cap, board)
    import finalize_routing as fr
    fr.route_rf(board)
    fr.route_usb(board)
    data = cap.as_json()
    data["rule_areas"] = [
        {"name": "USB_ESD_BREAKOUT", "layers": ["F.Cu"], "rect": [29.90, 50.70, 32.10, 53.10]},
        {"name": "RF_NO_DIGITAL", "layers": ["B.Cu", "In2.Cu", "In4.Cu", "In5.Cu"],
         "rect": [152.00, 36.00, 174.50, 43.70]},
    ]
    fence = [[x, 38.7] for x in range(153, 174, 2)] + [[x, 45.0] for x in range(161, 174, 2)]
    data["ground_zones"] = [{
        "net": "GND", "layer": "F.Cu", "clearance": 0.20, "min_thickness": 0.10,
        "priority": 100,
        "outline": [[152.0, 36.0], [174.5, 36.0], [174.5, 49.5], [152.0, 49.5]],
        "via_fence": fence,
    }]
    (ROOT / "hardware" / "critical_routes.json").write_text(json.dumps(data, indent=1) + "\n")
    print(f"critical_routes.json: {len(data['tracks'])} polylines, {len(cap.vias)} vias, "
          f"{len(data['rule_areas'])} rule areas, fence {len(fence)}")


if __name__ == "__main__":
    main()