from __future__ import annotations

import sys
from pathlib import Path


HERE = Path(__file__).resolve().parent

SCALE = 9.5  # points per inch
LEFT = 48.0
RIGHT = 56.0
TOP = 28.0
BOTTOM = 38.0

STIRRUP_STROKE = 2.0  # drawn stirrup line width, points
STIRRUP_RADIUS = 3.0  # drawn stirrup corner radius, points
DRAW_COVER = 1.0  # schematic cover shown in the drawing, inches

MUTED = 'rgb("#626b73")'


def _f(value: float) -> str:
    return f"{value:.4g}"


def _centers(size: float, number: int, bw: float, edge: float) -> list[float]:
    half = size / 2.0
    left = edge + half
    right = bw - left
    if number == 1:
        return [bw / 2.0]
    return [left + index * (right - left) / (number - 1) for index in range(number)]


def render(values: dict) -> str:
    s = SCALE
    bw = float(values["bw"])
    h = float(values["h"])
    stirrup_size = int(values["stirrup_size"])
    stirrup_spacing = float(values["stirrup_spacing"])
    bar_size = int(values["bar_size"])
    bar_db = float(values["bar_db"])
    n_bars = int(values["n_bars"])
    top_bar_size = int(values["top_bar_size"])
    top_bar_db = float(values["top_bar_db"])
    n_top_bars = int(values["n_top_bars"])

    w_sec = bw * s
    h_sec = h * s
    width = LEFT + w_sec + RIGHT
    height = TOP + h_sec + BOTTOM
    ox = LEFT
    oy = TOP

    def sx(x_in: float) -> float:
        return ox + x_in * s

    def sy(y_in: float) -> float:
        return oy + (h - y_in) * s

    edge = DRAW_COVER + STIRRUP_STROKE / s
    inset = DRAW_COVER + STIRRUP_STROKE / s / 2.0
    y_bottom = edge + bar_db / 2.0
    bottom = _centers(bar_db, n_bars, bw, edge)
    top_y = h - (edge + top_bar_db / 2.0)
    top = _centers(top_bar_db, n_top_bars, bw, edge)

    lines: list[str] = []
    add = lines.append
    add("// Generated by beam_section.py from input.yaml - do not edit by hand.")
    add("#let beam-section() = {")
    add(f"  box(width: {_f(width)}pt, height: {_f(height)}pt)[")

    add(
        f"    #place(dx: {_f(ox)}pt, dy: {_f(oy)}pt, "
        f'rect(width: {_f(w_sec)}pt, height: {_f(h_sec)}pt, fill: rgb("#f2f2f2"), stroke: 1pt + black))'
    )
    add(
        f"    #place(dx: {_f(sx(inset))}pt, dy: {_f(sy(h - inset))}pt, "
        f"rect(width: {_f((bw - 2.0 * inset) * s)}pt, height: {_f((h - 2.0 * inset) * s)}pt, "
        f"radius: {_f(STIRRUP_RADIUS)}pt, stroke: {_f(STIRRUP_STROKE)}pt + black))"
    )

    for x_in in bottom:
        r = bar_db / 2.0 * s
        add(
            f"    #place(dx: {_f(sx(x_in) - r)}pt, dy: {_f(sy(y_bottom) - r)}pt, "
            f"circle(radius: {_f(r)}pt, fill: black))"
        )
    for x_in in top:
        r = top_bar_db / 2.0 * s
        add(
            f"    #place(dx: {_f(sx(x_in) - r)}pt, dy: {_f(sy(top_y) - r)}pt, "
            f"circle(radius: {_f(r)}pt, fill: black))"
        )

    dim_y = oy + h_sec + 16.0
    add(
        f"    #place(line(start: ({_f(ox)}pt, {_f(dim_y)}pt), end: ({_f(ox + w_sec)}pt, {_f(dim_y)}pt), "
        f"stroke: 0.6pt + black))"
    )
    for tick in (ox, ox + w_sec):
        add(
            f"    #place(line(start: ({_f(tick)}pt, {_f(dim_y - 3)}pt), end: ({_f(tick)}pt, {_f(dim_y + 3)}pt), "
            f"stroke: 0.6pt + black))"
        )
    add(
        f"    #place(dx: {_f(ox)}pt, dy: {_f(dim_y + 3)}pt, "
        f'box(width: {_f(w_sec)}pt, align(center, text(size: 7pt)[$b_w = {_f(bw)} " in"$])))'
    )

    x_h = ox - 6.0
    add(
        f"    #place(line(start: ({_f(x_h)}pt, {_f(oy)}pt), end: ({_f(x_h)}pt, {_f(oy + h_sec)}pt), "
        f"stroke: 0.6pt + black))"
    )
    for tick in (oy, oy + h_sec):
        add(
            f"    #place(line(start: ({_f(x_h - 3)}pt, {_f(tick)}pt), end: ({_f(x_h + 3)}pt, {_f(tick)}pt), "
            f"stroke: 0.6pt + black))"
        )
    add(
        f"    #place(dx: 0.5pt, dy: {_f(oy + h_sec / 2.0 - 3)}pt, "
        f'text(size: 7pt)[$h = {_f(h)} " in"$])'
    )

    label_x = ox + w_sec + 8.0
    lead_x = ox + w_sec + 5.0

    def leader(fx: float, fy: float, lx: float, ly: float) -> None:
        add(
            f"    #place(line(start: ({_f(fx)}pt, {_f(fy)}pt), end: ({_f(lx)}pt, {_f(ly)}pt), "
            f"stroke: 0.5pt + {MUTED}))"
        )
        add(f"    #place(dx: {_f(fx - 1.5)}pt, dy: {_f(fy - 1.5)}pt, circle(radius: 1.5pt, fill: black))")

    leader(sx(top[-1]), sy(top_y), lead_x, oy + 14.0)
    add(
        f"    #place(dx: {_f(label_x)}pt, dy: {_f(oy + 9)}pt, "
        f'text(size: 7pt, "({n_top_bars}) #{top_bar_size}"))'
    )

    leader(sx(bw - inset), sy(h / 2.0), lead_x, oy + h_sec / 2.0 - 3.0)
    add(
        f"    #place(dx: {_f(label_x)}pt, dy: {_f(oy + h_sec / 2.0 - 8)}pt, "
        f'text(size: 7pt, "#{stirrup_size} @ {_f(stirrup_spacing)}″"))'
    )

    leader(sx(bottom[-1]), sy(y_bottom), lead_x, oy + h_sec - 14.0)
    add(
        f"    #place(dx: {_f(label_x)}pt, dy: {_f(oy + h_sec - 19)}pt, "
        f'text(size: 7pt, "({n_bars}) #{bar_size}"))'
    )

    add("  ]")
    add("}")
    return "\n".join(lines) + "\n"


def write_fragment(values: dict, path: Path) -> None:
    path.write_text(render(values), encoding="utf-8")


def main(argv: list[str] | None = None) -> int:
    argv = sys.argv[1:] if argv is None else argv
    input_path = Path(argv[0]) if argv else HERE / "input.yaml"
    output_path = Path(argv[1]) if len(argv) > 1 else HERE / "assets" / "beam-section.typ"

    import yaml
    import calc

    with input_path.open(encoding="utf-8") as handle:
        result = calc.compute(yaml.safe_load(handle))
    write_fragment(result["values"], output_path)
    print(output_path)
    return 0


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