#!/usr/bin/env python3

from math import *
from pathlib import Path
from itertools import cycle

from gerbonara.cad.kicad import pcb as kicad_pcb
from gerbonara.cad.kicad import graphical_primitives as kicad_gr
import click


def point_line_distance(p, l1, l2):
    x0, y0 = p
    x1, y1 = l1
    x2, y2 = l2
    # https://en.wikipedia.org/wiki/Distance_from_a_point_to_a_line
    return abs((x2-x1)*(y1-y0) - (x1-x0)*(y2-y1)) / sqrt((x2-x1)**2 + (y2-y1)**2)


@click.command()
@click.argument('infile', type=click.Path(exists=True, dir_okay=False, path_type=Path))
@click.argument('outfile', type=click.Path(writable=True, dir_okay=False, path_type=Path))
@click.option('--polygon', type=int, default=0, help="Use n'th polygon instead of first one. 0-based index.")
@click.option('--start-angle', type=float, default=0, help='Angle for the start at the outermost layer of the spiral in degree')
@click.option('--stop-radius', type=float, default=1, help='Inner radius of spiral')
@click.option('--trace-width', type=float, default=0.15)
@click.option('--clearance', type=float, default=0.15)
def generate(infile, outfile, polygon, start_angle, stop_radius, trace_width, clearance):
    board = kicad_pcb.Board.open(infile)
    objs = [obj for obj in board.objects() if isinstance(obj, kicad_gr.Polygon)]
    print(f'Found {len(objs)} polygon(s).')
    poly = objs[polygon]
    xy = [(pt.x, pt.y) for pt in poly.pts.xy]
    segments = list(zip(xy, xy[1:] + xy[:1]))

    vbx, vby = min(x for x, y in xy), min(y for x, y, in xy)
    vbw, vbh = max(x for x, y in xy), max(y for x, y, in xy)
    vbw, vbh = vbw-vbx, vbh-vby

    vbx -= 5
    vby -= 5
    vbw += 10
    vbh += 10

    cx, cy = 0, 0
    ls = 0
    for (x1, y1), (x2, y2) in segments:
        l = dist((x1, y1), (x2, y2))
        cx += x1*l/2 + x2*l/2
        cy += y1*l/2 + y2*l/2
        ls += l
    cx /= ls
    cy /= ls

    segment_angles = [(atan2(y1-cy, x1-cx) - atan2(y2-cy, x2-cx) + 2*pi) % (2*pi) for (x1, y1), (x2, y2) in segments]
    angle_strs = [f'{degrees(a):.2f}' for a in segment_angles]
    print(f'Segment angles: {" ".join(angle_strs)}')
    print(f'Sum of segment angles: {degrees(sum(segment_angles)):.2f}')

    segment_heights = [point_line_distance((cx, cy), (x1, y1), (x2, y2)) for (x1, y1), (x2, y2) in segments]

    closest_points = []
    for h, ((x1, y1), (x2, y2)) in zip(segment_heights, segments):
        dc1 = dist((x1, y1), (cx, cy))
        d12 = dist((x1, y1), (x2, y2))
        db = sqrt(dc1**2 - h**2)
        xn = (x2 - x1) / d12
        yn = (y2 - y1) / d12
        xb = x1 + xn * db
        yb = y1 + yn * db
        closest_points.append((xb, yb))

    smallest_radius = min(segment_heights)
    #trace_radius = smallest_radius - stop_radius
    trace_radius = smallest_radius
    num_windings = floor((trace_radius - trace_width) / (clearance + trace_width))
    print(f'Going for {num_windings} windings')

    spiral_points = []
    r_now = 0
    for winding in range(num_windings):
        for angle, ((x1, y1), (x2, y2)) in zip(segment_angles, segments):
            angle_frac = angle/(2*pi)
            d_r = angle_frac * (clearance + trace_width)
            r_pt = dist((cx, cy), (x1, y1)) * (num_windings - winding) / num_windings

            x1, y1 = x1-cx, y1-cy
            x2, y2 = x2-cx, y2-cy
            l1, l2 = hypot(x1, y1), hypot(x2, y2)
            x1, y1 = x1/l1, y1/l1
            x2, y2 = x2/l2, y2/l2

            r_now += d_r
            spiral_points.append((cx + x1*r_pt, cy + y1*r_pt))

    path_d = ' '.join([f'M {xy[0][0]} {xy[0][1]}', *[f'L {x} {y}' for x, y in xy[1:]], 'Z'])
    path_d2 = ' '.join(f'M {cx} {cy} L {x} {y}' for x, y in xy)
    path_d3 = ' '.join([f'M {spiral_points[0][0]} {spiral_points[0][1]}', *[f'L {x} {y}' for x, y in spiral_points[1:]]])
    
    with open('/tmp/test.svg', 'w') as f:
        f.write('<?xml version="1.0" standalone="no"?>\n')
        f.write('<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">\n')
        f.write(f'<svg version="1.1" width="200mm" height="200mm" viewBox="{vbx} {vby} {vbw} {vbh}" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">>\n')
        f.write(f'<path fill="none" stroke="#303030" stroke-width="0.05" d="{path_d}"/>\n')
        f.write(f'<path fill="none" stroke="#a0a0a0" stroke-width="0.05" d="{path_d2}"/>\n')
        #f.write(f'<path fill="none" stroke="#ff00ff" stroke-width="{trace_width}" d="{path_d3}"/>\n')
        f.write(f'<circle r="0.1" fill="red" stroke="none" cx="{cx}" cy="{cy}"/>\n')
        for x, y in closest_points:
            f.write(f'<circle r="0.1" fill="blue" stroke="none" cx="{x}" cy="{y}"/>\n')
            f.write(f'<path fill="none" stroke="#a0a0ff" stroke-width="0.05" d="M {cx} {cy} L {x} {y}"/>')
        f.write('</svg>\n')

if __name__ == '__main__':
    generate()