# -*- coding: utf-8 -*-

def b_poly_arc_augmented(p_list, or_list):
    r_list = or_list[:]
    a_list = []
    
    for i1, p1 in enumerate(p_list):
        i2 = (i1 + 1) % len(p_list)
        p2, r2, r1 = p_list[i2], r_list[i2], r_list[i1]
        r_list[i1], r_list[i2] = reduce_radius(p1, p2, r1, r2)

    for i1, p1 in enumerate(p_list):
        i2 = (i1 + 1) % len(p_list)
        p2, r2, r1 = p_list[i2], r_list[i2], r_list[i1]
        a = circ_circ_tangent(p1, p2, r1, r2)
        a_list.append(a)

    beginShape()
    for i1, _ in enumerate(a_list):
        i2 = (i1 + 1) % len(a_list)
        p1, p2, r1, r2 = p_list[i1], p_list[i2], r_list[i1], r_list[i2]
        a1, P11, P12 = a_list[i1]
        a2, P21, P22 = a_list[i2]
        if a1 and a2:
            start = a1 if a1 < a2 else a1 - TWO_PI
            b_arc(p2[0], p2[1], r2 * 2, r2 * 2, start, a2, arc_type=2)
        else:
            # ellipse(p2[0], p2[1], r2 * 2, r2 * 2)
            if a1:
                vertex(P12[0], P12[1])
            if a2:
                vertex(P21[0], P21[1])
    endShape(CLOSE)

def reduce_radius(p1, p2, r1, r2):
    d = dist(p1[0], p1[1], p2[0], p2[1])
    ri = r1 - r2
    delta = d - abs(ri)
    if delta > 0:
        return(r1, r2)
    else:
        if r2 > r1:
             r2 += delta * 2
        else:
             r1 += delta * 2
        print(r1, r2, d, ri, delta)
        return(r1, r2)

def circ_circ_tangent(p1, p2, r1, r2):
    d = dist(p1[0], p1[1], p2[0], p2[1])
    ri = r1 - r2
    line_angle = atan2(p1[0] - p2[0], p2[1] - p1[1])
    if d > abs(ri):
        theta = asin(ri / float(d))
        x1 = cos(line_angle - theta) * r1
        y1 = sin(line_angle - theta) * r1
        x2 = cos(line_angle - theta) * r2
        y2 = sin(line_angle - theta) * r2
        x1 = -cos(line_angle + theta) * r1
        y1 = -sin(line_angle + theta) * r1
        x2 = -cos(line_angle + theta) * r2
        y2 = -sin(line_angle + theta) * r2
        # line(p1[0] - x1, p1[1] - y1, p2[0] - x2, p2[1] - y2)
        return (line_angle + theta,
                (p1[0] - x1, p1[1] - y1),
                (p2[0] - x2, p2[1] - y2))
    else:
        # line(p1[0], p1[1], p2[0], p2[1])
        return (None,
                (p1[0], p1[1]),
                (p2[0], p2[1]))


def b_poly_filleted(p_list, r_list=None, open_poly=False):
    """
    draws a 'filleted' polygon with variable radius
    dependent on roundedCorner()
    """
    if not r_list:
        r_list = [0] * len(p_list)
    beginShape()
    for p0, p1, p2, r in zip(p_list,
                             [p_list[-1]] + p_list[:-1],
                             [p_list[-2]] + [p_list[-1]] + p_list[:-2],
                             [r_list[-1]] + r_list[:-1]
                             ):
        m1 = (PVector(p0[0], p0[1]) + PVector(p1[0], p1[1])) / 2
        m2 = (PVector(p2[0], p2[1]) + PVector(p1[0], p1[1])) / 2
        b_roundedCorner(p1, m1, m2, r)
    endShape(CLOSE)

def b_roundedCorner(pc, p2, p1, r):
    """
    Based on Stackoverflow C# rounded corner post 
    https://stackoverflow.com/questions/24771828/algorithm-for-creating-rounded-corners-in-a-polygon
    """
    def GetProportionPoint(pt, segment, L, dx, dy):
        factor = float(segment) / L if L != 0 else segment
        return PVector((pt[0] - dx * factor), (pt[1] - dy * factor))

    # Vector 1
    dx1 = pc[0] - p1[0]
    dy1 = pc[1] - p1[1]
    # Vector 2
    dx2 = pc[0] - p2[0]
    dy2 = pc[1] - p2[1]
    # Angle between vector 1 and vector 2 divided by 2
    angle = (atan2(dy1, dx1) - atan2(dy2, dx2)) / 2
    # The length of segment between angular point and the
    # points of intersection with the circle of a given radius
    tng = abs(tan(angle))
    segment = r / tng if tng != 0 else r
    # Check the segment
    length1 = sqrt(dx1 * dx1 + dy1 * dy1)
    length2 = sqrt(dx2 * dx2 + dy2 * dy2)
    min_len = min(length1, length2)
    if segment > min_len:
        segment = min_len
        max_r = min_len * abs(tan(angle))
    else:
        max_r = r
    # Points of intersection are calculated by the proportion between
    # length of vector and the length of the segment.
    p1Cross = GetProportionPoint(pc, segment, length1, dx1, dy1)
    p2Cross = GetProportionPoint(pc, segment, length2, dx2, dy2)
    # Calculation of the coordinates of the circle
    # center by the addition of angular vectors.
    dx = pc[0] * 2 - p1Cross[0] - p2Cross[0]
    dy = pc[1] * 2 - p1Cross[1] - p2Cross[1]
    L = sqrt(dx * dx + dy * dy)
    d = sqrt(segment * segment + max_r * max_r)
    circlePoint = GetProportionPoint(pc, d, L, dx, dy)
    # StartAngle and EndAngle of arc
    startAngle = atan2(
        p1Cross[1] - circlePoint[1], p1Cross[0] - circlePoint[0])
    endAngle = atan2(p2Cross[1] - circlePoint[1], p2Cross[0] - circlePoint[0])
    # Sweep angle
    sweepAngle = endAngle - startAngle
    # Some additional checks
    A, B = False, False

    if sweepAngle < 0:
        A = True
        startAngle, endAngle = endAngle, startAngle
        sweepAngle = -sweepAngle
        ellipse(pc[0], pc[1], 15, 15)

    if sweepAngle > PI:
        B = True
        startAngle, endAngle = endAngle, startAngle
        sweepAngle = TWO_PI - sweepAngle
        ellipse(pc[0], pc[1], 25, 25)

    if (A and not B) or (B and not A):
        startAngle, endAngle = endAngle, startAngle
        sweepAngle = -sweepAngle
        ellipse(pc[0], pc[1], 5, 5)

    b_arc(circlePoint[0], circlePoint[1], 2 * max_r, 2 * max_r,
          startAngle, startAngle + sweepAngle, arc_type=2)

def b_arc(cx, cy, w, h, startAngle, endAngle, arc_type=0):
    """
    A bezier approximation of an arc
    using the same signature as the original Processing arc()
    arc_type: 0 "normal" arc, using beginShape() and endShape()
              1 "middle" used in recursive call of smaller arcs
              2 "naked" like normal, but without beginShape() and endShape()
                 for use inside a larger PShape
    """
    theta = endAngle - startAngle

    if arc_type != 1 or theta < HALF_PI:
        # Compute raw Bezier coordinates.
        x0 = cos(theta / 2.0)
        y0 = sin(theta / 2.0)
        x3 = x0
        y3 = 0 - y0
        x1 = (4.0 - x0) / 3.0
        if y0 != 0:
            y1 = ((1.0 - x0) * (3.0 - x0)) / (3.0 * y0)  # y0 != 0...
        else:
            y1 = 0
        x2 = x1
        y2 = 0 - y1
        # Compute rotationally-offset Bezier coordinates, using:
        # x' = cos(angle) * x - sin(angle) * y
        # y' = sin(angle) * x + cos(angle) * y
        bezAng = startAngle + theta / 2.0
        cBezAng = cos(bezAng)
        sBezAng = sin(bezAng)
        rx0 = cBezAng * x0 - sBezAng * y0
        ry0 = sBezAng * x0 + cBezAng * y0
        rx1 = cBezAng * x1 - sBezAng * y1
        ry1 = sBezAng * x1 + cBezAng * y1
        rx2 = cBezAng * x2 - sBezAng * y2
        ry2 = sBezAng * x2 + cBezAng * y2
        rx3 = cBezAng * x3 - sBezAng * y3
        ry3 = sBezAng * x3 + cBezAng * y3

        # Compute scaled and translated Bezier coordinates.
        rx, ry = w / 2.0, h / 2.0
        px0 = cx + rx * rx0
        py0 = cy + ry * ry0
        px1 = cx + rx * rx1
        py1 = cy + ry * ry1
        px2 = cx + rx * rx2
        py2 = cy + ry * ry2
        px3 = cx + rx * rx3
        py3 = cy + ry * ry3
        # Debug points... comment this out!
        # ellipse(px3, py3, 15, 15)
        # ellipse(px0, py0, 5, 5)

    # Drawing
    if arc_type == 0:
        beginShape()
    if arc_type != 1:
        vertex(px3, py3)
    if theta < HALF_PI:
        bezierVertex(px2, py2, px1, py1, px0, py0)
    else:
        b_arc(cx, cy, w, h, startAngle, endAngle - theta / 2.0, arc_type=1)
        b_arc(cx, cy, w, h, startAngle + theta / 2.0, endAngle, arc_type=1)
    if arc_type == 0:
        endShape()