import sys
import re
import math
import string
import itertools
from copy import copy, deepcopy
import warnings
import importlib.resources

from .primitives import *
from ..graphic_objects import Region
from ..apertures import RectangleAperture, CircleAperture
from .kicad import footprints as kfp
from . import data as package_data


class ProtoBoard(Board):
    def __init__(self, w, h, content, margin=None, corner_radius=None, mounting_hole_dia=None, mounting_hole_offset=None, unit=MM):
        corner_radius = corner_radius or unit(1.5, MM)
        super().__init__(w, h, corner_radius, unit=unit)
        self.margin = margin or unit(2, MM)
        self.content = content

        if mounting_hole_dia:
            mounting_hole_offset = mounting_hole_offset or mounting_hole_dia*2
            ko = mounting_hole_offset*2

            self.add(Hole(mounting_hole_offset, mounting_hole_offset, mounting_hole_dia, unit=unit))
            self.add(Hole(w-mounting_hole_offset, mounting_hole_offset, mounting_hole_dia, unit=unit))
            self.add(Hole(mounting_hole_offset, h-mounting_hole_offset, mounting_hole_dia, unit=unit))
            self.add(Hole(w-mounting_hole_offset, h-mounting_hole_offset, mounting_hole_dia, unit=unit))

            self.keepouts.append(((0, 0), (ko, ko)))
            self.keepouts.append(((w-ko, 0), (w, ko)))
            self.keepouts.append(((0, h-ko), (ko, h)))
            self.keepouts.append(((w-ko, h-ko), (w, h)))

        self.generate()

    def generate(self, unit=MM):
        bbox = ((self.margin, self.margin), (self.w-self.margin, self.h-self.margin))
        bbox = unit.convert_bounds_from(self.unit, bbox)
        for obj in self.content.generate(bbox, (True, True, True, True), unit):
            self.add(obj, keepout_errors='skip')


class PropLayout:
    def __init__(self, content, direction, proportions):
        self.content = list(content)
        if direction not in ('h', 'v'):
            raise ValueError('direction must be one of "h", or "v".')
        self.direction = direction
        self.proportions = list(proportions)
        if len(content) != len(proportions):
            raise ValueError('proportions and content must have same length')

    def generate(self, bbox, border_text, unit=MM):
        for i, (bbox, child) in enumerate(self.layout_2d(bbox, unit)):
            first = bool(i == 0)
            last = bool(i == len(self.content)-1)
            yield from child.generate(bbox, (
                border_text[0] and (last or self.direction == 'h'),
                border_text[1] and (last or self.direction == 'v'),
                border_text[2] and (first or self.direction == 'h'),
                border_text[3] and (first or self.direction == 'v'),
                ), unit)

    def fit_size(self, w, h, unit=MM):
        widths = []
        heights = []
        for ((x_min, y_min), (x_max, y_max)), child in self.layout_2d(((0, 0), (w, h)), unit):
            if not isinstance(child, EmptyProtoArea):
                widths.append(x_max - x_min)
                heights.append(y_max - y_min)
        if self.direction == 'h':
            return sum(widths), max(heights)
        else:
            return max(widths), sum(heights)

    def layout_2d(self, bbox, unit=MM):
        (x, y), (w, h) = bbox
        w, h = w-x, h-y

        actual_l = 0
        target_l = 0

        for l, child in zip(self.layout(w if self.direction == 'h' else h, unit), self.content):
            this_x, this_y = x, y
            this_w, this_h = w, h
            target_l += l

            if self.direction == 'h':
                this_w = target_l - actual_l
            else:
                this_h = target_l - actual_l

            this_w, this_h = child.fit_size(this_w, this_h, unit)

            if self.direction == 'h':
                x += this_w
                actual_l += this_w
                this_h = h
            else:
                y += this_h
                actual_l += this_h
                this_w = w

            yield ((this_x, this_y), (this_x+this_w, this_y+this_h)), child

    def layout(self, length, unit=MM):
        out = [ eval_value(value, MM(length, unit)) for value in self.proportions ]
        total_length = sum(value for value in out if value is not None)
        if length - total_length < -1e-6:
            raise ValueError(f'Proportions sum to {total_length} mm, which is greater than the available space of {length} mm.')

        leftover = length - total_length
        sum_props = sum( (value or 1.0) for value in self.proportions if not isinstance(value, str) )
        return [ unit(leftover * (value or 1.0) / sum_props if not isinstance(value, str) else calculated, MM)
                for value, calculated in zip(self.proportions, out) ]

    @property
    def single_sided(self):
        return all(elem.single_sided for elem in self.content)

    def __str__(self):
        children = ', '.join( f'{elem}:{width}' for elem, width in zip(self.content, self.proportions))
        return f'PropLayout[{self.direction.upper()}]({children})'


class TwoSideLayout:
    def __init__(self, top, bottom):
        self.top, self.bottom = top, bottom

        if not top.single_sided or not bottom.single_sided:
            warnings.warn('Two-sided pattern used on one side of a TwoSideLayout')

    def fit_size(self, w, h, unit=MM):
        w1, h1 = self.top.fit_size(w, h, unit)
        w2, h2 = self.bottom.fit_size(w, h, unit)
        if isinstance(self.top, EmptyProtoArea):
            if isinstance(self.bottom, EmptyProtoArea):
                return w1, h1
            return w2, h2
        if isinstance(self.bottom, EmptyProtoArea):
            return w1, h1
        return max(w1, w2), max(h1, h2)

    def generate(self, bbox, border_text, unit=MM):
        yield from self.top.generate(bbox, border_text, unit)
        for obj in self.bottom.generate(bbox, border_text, unit):
            obj.side = 'bottom'
            yield obj


def numeric(start=1):
    def gen():
        nonlocal start
        for i in itertools.count(start):
            yield str(i)

    return gen


def alphabetic(case='upper'):
    if case not in ('lower', 'upper'):
        raise ValueError('case must be one of "lower" or "upper".')

    index = string.ascii_lowercase if case == 'lower' else string.ascii_uppercase

    def gen():
        nonlocal index

        for i in itertools.count():
            if i<26:
                yield index[i]
                continue

            i -= 26
            if i<26*26:
                yield index[i//26] + index[i%26]
                continue

            i -= 26*26
            if i<26*26*26:
                yield index[i//(26*26)] + index[(i//26)%26] + index[i%26]

            else:
                raise ValueError('row/column index out of range')

    return gen


class PatternProtoArea:
    def __init__(self, pitch_x, pitch_y=None, obj=None, numbers=True, font_size=None, font_stroke=None, number_x_gen=alphabetic(), number_y_gen=numeric(), interval_x=5, interval_y=None, unit=MM):
        self.pitch_x = pitch_x
        self.pitch_y = pitch_y or pitch_x
        self.obj = obj
        self.unit = unit
        self.numbers = numbers
        self.font_size = font_size or unit(1.0, MM)
        self.font_stroke = font_stroke or unit(0.2, MM)
        self.interval_x = interval_x
        self.interval_y = interval_y or (1 if MM(self.pitch_y, unit) >= 2.0 else 5)
        self.number_x_gen, self.number_y_gen = number_x_gen, number_y_gen

    def fit_size(self, w, h, unit=MM):
        (min_x, min_y), (max_x, max_y) = self.fit_rect(((0, 0), (w, h)))
        return max_x-min_x, max_y-min_y

    def fit_rect(self, bbox, unit=MM):
        (x, y), (w, h) = bbox
        w, h = w-x, h-y

        w_mod = round((w + 5e-7) % unit(self.pitch_x, self.unit), 6)
        h_mod = round((h + 5e-7) % unit(self.pitch_y, self.unit), 6)
        w_fit, h_fit = round(w - w_mod, 6), round(h - h_mod, 6)

        x = x + (w-w_fit)/2
        y = y + (h-h_fit)/2
        return (x, y), (x+w_fit, y+h_fit)

    def generate(self, bbox, border_text, unit=MM):
        (x, y), (w, h) = bbox
        w, h = w-x, h-y

        n_x = int(w//unit(self.pitch_x, self.unit))
        n_y = int(h//unit(self.pitch_y, self.unit))
        off_x = (w % unit(self.pitch_x, self.unit)) / 2
        off_y = (h % unit(self.pitch_y, self.unit)) / 2

        if self.numbers:
            for i, lno_i in list(zip(range(n_y), self.number_y_gen())):
                if i == 0 or i == n_y - 1 or (i+1) % self.interval_y == 0:
                    t_y = off_y + y + (n_y - 1 - i + 0.5) * self.pitch_y

                    if border_text[3]:
                        t_x = x + off_x
                        yield Text(t_x, t_y, lno_i, self.font_size, self.font_stroke, 'right', 'middle', unit=self.unit)
                        if not self.single_sided:
                            yield Text(t_x, t_y, lno_i, self.font_size, self.font_stroke, 'right', 'middle', side='bottom', unit=self.unit)

                    if border_text[1]:
                        t_x = x + w - off_x
                        yield Text(t_x, t_y, lno_i, self.font_size, self.font_stroke, 'left', 'middle', unit=self.unit)
                        if not self.single_sided:
                            yield Text(t_x, t_y, lno_i, self.font_size, self.font_stroke, 'left', 'middle', side='bottom', unit=self.unit)

            for i, lno_i in zip(range(n_x), self.number_x_gen()):
                if i == 0 or i == n_x - 1 or (i+1) % self.interval_x == 0:
                    t_x = off_x + x + (i + 0.5) * self.pitch_x

                    if border_text[2]:
                        t_y = y + off_y
                        yield Text(t_x, t_y, lno_i, self.font_size, self.font_stroke, 'center', 'top', unit=self.unit)
                        if not self.single_sided:
                            yield Text(t_x, t_y, lno_i, self.font_size, self.font_stroke, 'center', 'top', side='bottom', unit=self.unit)

                    if border_text[0]:
                        t_y = y + h - off_y
                        yield Text(t_x, t_y, lno_i, self.font_size, self.font_stroke, 'center', 'bottom', unit=self.unit)
                        if not self.single_sided:
                            yield Text(t_x, t_y, lno_i, self.font_size, self.font_stroke, 'center', 'bottom', side='bottom', unit=self.unit)


        for i in range(n_x):
            for j in range(n_y):
                if hasattr(self.obj, 'inst'):
                    inst = self.obj.inst(i, j, i == n_x-1, j == n_y-1)
                    if not inst:
                        continue
                else:
                    inst = copy(self.obj)

                inst.x = inst.unit(off_x + x, unit) + (i + 0.5) * inst.unit(self.pitch_x, self.unit)
                inst.y = inst.unit(off_y + y, unit) + (j + 0.5) * inst.unit(self.pitch_y, self.unit)
                yield inst

    @property
    def single_sided(self):
        return self.obj.single_sided


class EmptyProtoArea:
    def __init__(self, copper_fill=False):
        self.copper_fill = copper_fill

    def fit_size(self, w, h, unit=MM):
        return w, h

    def generate(self, bbox, border_text, unit=MM):
        if self.copper_fill:
            (min_x, min_y), (max_x, max_y) = bbox
            group = ObjectGroup(0, 0, top_copper=[Region([(min_x, min_y), (max_x, min_y), (max_x, max_y), (min_x, max_y)],
                                                unit=unit, polarity_dark=True)])
            group.bounding_box = lambda *args, **kwargs: None
            yield group

    @property
    def single_sided(self):
        return True


class ManhattanPads(ObjectGroup):
    def __init__(self, w, h=None, gap=0.2, unit=MM):
        super().__init__(0, 0)
        h = h or w
        self.gap = gap
        self.unit = unit

        p = (w-2*gap)/2
        q = (h-2*gap)/2
        small_ap = RectangleAperture(p, q, unit=unit)

        s = min(w, h) / 2 / math.sqrt(2)
        large_ap = RectangleAperture(s, s, rotation=math.pi/4, unit=unit)
        large_ap_neg = RectangleAperture(s+2*gap, s+2*gap, rotation=math.pi/4, unit=unit)

        a = gap/2 + p/2
        b = gap/2 + q/2

        self.top_copper.append(Flash(-a, -b, aperture=small_ap, unit=unit))
        self.top_copper.append(Flash(-a,  b, aperture=small_ap, unit=unit))
        self.top_copper.append(Flash( a, -b, aperture=small_ap, unit=unit))
        self.top_copper.append(Flash( a,  b, aperture=small_ap, unit=unit))
        self.top_copper.append(Flash(0, 0, aperture=large_ap_neg, polarity_dark=False, unit=unit))
        self.top_copper.append(Flash(0, 0, aperture=large_ap, unit=unit))
        self.top_mask = self.top_copper


class RFGroundProto(ObjectGroup):
    def __init__(self, pitch=None, drill=None, clearance=None, via_dia=None, via_drill=None, pad_dia=None, trace_width=None, unit=MM):
        super().__init__(0, 0)
        self.unit = unit
        self.pitch = pitch = pitch or unit(2.54, MM)
        self.drill = drill = drill or unit(0.9, MM)
        self.clearance = clearance = clearance or unit(0.3, MM)
        self.via_drill = via_drill = via_drill or unit(0.4, MM)
        self.via_dia = via_dia = via_dia or unit(0.8, MM)

        if pad_dia is None:
            self.trace_width = trace_width = trace_width or unit(0.3, MM)
            pad_dia = pitch - trace_width - 2*clearance 
        elif trace_width is None:
            trace_width = pitch - pad_dia - 2*clearance
        self.pad_dia = pad_dia

        via_ap = RectangleAperture(via_dia, via_dia, rotation=math.pi/4, unit=unit)
        pad_ap = CircleAperture(pad_dia, unit=unit)
        pad_neg_ap = CircleAperture(pad_dia+2*clearance, unit=unit)
        ground_ap = RectangleAperture(pitch + unit(0.01, MM), pitch + unit(0.01, MM), unit=unit)
        pad_drill = ExcellonTool(drill, plated=True, unit=unit)
        via_drill = ExcellonTool(via_drill, plated=True, unit=unit)

        self.top_copper.append(Flash(0, 0, aperture=ground_ap, unit=unit))
        self.top_copper.append(Flash(0, 0, aperture=pad_neg_ap, polarity_dark=False, unit=unit))
        self.top_copper.append(Flash(0, 0, aperture=pad_ap, unit=unit))
        self.top_mask.append(Flash(0, 0, aperture=pad_ap, unit=unit))
        self.top_copper.append(Flash(pitch/2, pitch/2, aperture=via_ap, unit=unit))
        self.top_mask.append(Flash(pitch/2, pitch/2, aperture=via_ap, unit=unit))
        self.drill_pth.append(Flash(0, 0, aperture=pad_drill, unit=unit))
        self.drill_pth.append(Flash(pitch/2, pitch/2, aperture=via_drill, unit=unit))

        self.bottom_copper = self.top_copper
        self.bottom_mask = self.top_mask

    def inst(self, x, y, border_x, border_y):
        inst = copy(self)
        if border_x or border_y:
            inst.drill_pth = inst.drill_pth[:-1]
            inst.top_copper = inst.bottom_copper = inst.top_copper[:-1]
            inst.top_mask = inst.bottom_mask = inst.top_mask[:-1]
        return inst


class THTFlowerProto(ObjectGroup):
    def __init__(self, pitch=None, drill=None, diameter=None, unit=MM):
        super().__init__(0, 0, unit=unit)
        self.pitch = pitch = pitch or unit(2.54, MM)
        drill = drill or unit(0.9, MM)
        diameter = diameter or unit(2.0, MM)

        p = pitch / 2
        self.objects.append(THTPad.circle(-p, 0, drill, diameter, paste=False, unit=unit))
        self.objects.append(THTPad.circle( p, 0, drill, diameter, paste=False, unit=unit))
        self.objects.append(THTPad.circle(0, -p, drill, diameter, paste=False, unit=unit))
        self.objects.append(THTPad.circle(0,  p, drill, diameter, paste=False, unit=unit))

        middle_ap = CircleAperture(diameter, unit=unit)
        self.top_copper.append(Flash(0, 0, aperture=middle_ap, unit=unit))
        self.bottom_copper = self.top_mask = self.bottom_mask = self.top_copper
    
    def inst(self, x, y, border_x, border_y):
        if (x % 2 == 0) and (y % 2 == 0):
            return copy(self)

        if (x % 2 == 1) and (y % 2 == 1):
            return copy(self)

        return None

    def bounding_box(self, unit=MM):
        x, y, rotation = self.abs_pos
        p = self.pitch/2
        return unit.convert_bounds_from(self.unit, ((x-p, y-p), (x+p, y+p)))

class PoweredProto(ObjectGroup):
    def __init__(self, pitch=None, drill=None, clearance=None, power_pad_dia=None, via_size=None, trace_width=None, unit=MM):
        super().__init__(0, 0)
        self.unit = unit
        self.pitch = pitch = pitch or unit(2.54, MM)
        self.drill = drill = drill or unit(0.9, MM)
        self.clearance = clearance = clearance or unit(0.3, MM)
        self.trace_width = trace_width = trace_width or unit(0.3, MM)
        self.via_size = via_size = via_size or unit(0.4, MM)

        main_pad_dia = pitch - trace_width - 2*clearance
        power_pad_dia_max = math.sqrt(2)*pitch - main_pad_dia - 2*clearance
        if power_pad_dia is None:
            power_pad_dia = power_pad_dia_max - clearance # reduce some more to give the user more room
        elif power_pad_dia > power_pad_dia_max:
            warnings.warn(f'Power pad diameter {power_pad_dia} > {power_pad_dia_max} violates pad-to-pad clearance')
        self.power_pad_dia = power_pad_dia

        main_ap = CircleAperture(main_pad_dia, unit=unit)
        power_ap = CircleAperture(self.power_pad_dia, unit=unit)

        for l in [self.top_copper, self.bottom_copper]:
            l.append(Flash(0, 0, aperture=main_ap, unit=unit))

            l.append(Flash(-pitch/2, -pitch/2, aperture=power_ap, unit=unit))
            l.append(Flash(-pitch/2,  pitch/2, aperture=power_ap, unit=unit))
            l.append(Flash( pitch/2, -pitch/2, aperture=power_ap, unit=unit))
            l.append(Flash( pitch/2,  pitch/2, aperture=power_ap, unit=unit))

        self.drill_pth.append(Flash(0, 0, ExcellonTool(drill, plated=True, unit=unit), unit=unit))
        self.drill_pth.append(Flash(-pitch/2, -pitch/2, ExcellonTool(via_size, plated=True, unit=unit), unit=unit))

        self.top_mask = copy(self.top_copper)
        self.bottom_mask = copy(self.bottom_copper)

        self.line_ap = CircleAperture(trace_width, unit=unit)
        self.top_copper.append(Line(-pitch/2, -pitch/2, -pitch/2, pitch/2, aperture=self.line_ap, unit=unit))
        self.top_copper.append(Line(pitch/2, -pitch/2, pitch/2, pitch/2, aperture=self.line_ap, unit=unit))
        self.bottom_copper.append(Line(-pitch/2, -pitch/2, pitch/2, -pitch/2, aperture=self.line_ap, unit=unit))
        self.bottom_copper.append(Line(-pitch/2, pitch/2, pitch/2, pitch/2, aperture=self.line_ap, unit=unit))

    def inst(self, x, y, border_x, border_y):
        inst = copy(self)
        if (x + y) % 2 == 0:
            inst.drill_pth = inst.drill_pth[:-1]

        c = self.power_pad_dia/2 + self.clearance
        p = self.pitch/2

        if x == 1:
            inst.top_silk = [Line(-p, -p+c, -p, p-c, aperture=self.line_ap, unit=self.unit)]
        elif x % 2 == 0:
            inst.top_silk = [Line(p, -p+c, p, p-c, aperture=self.line_ap, unit=self.unit)]

        if y == 0:
            inst.bottom_silk = [Line(-p+c, -p, p-c, -p, aperture=self.line_ap, unit=self.unit)]
        elif y % 2 == 1:
            inst.bottom_silk = [Line(-p+c, p, p-c, p, aperture=self.line_ap, unit=self.unit)]

        return inst

    def bounding_box(self, unit=MM):
        x, y, rotation = self.abs_pos
        p = self.pitch/2
        return unit.convert_bounds_from(self.unit, ((x-p, y-p), (x+p, y+p)))


class SpikyProto(ObjectGroup):
    def __init__(self, pitch=None, drill=None, clearance=None, power_pad_dia=None, via_size=None, trace_width=None, unit=MM):
        super().__init__(0, 0)
        res = importlib.resources.files(package_data)

        self.fp_center = kfp.Footprint.load(res.joinpath('center-pad-spikes.kicad_mod').read_text(encoding='utf-8'))
        self.objects.append(kfp.FootprintInstance(1.27, 1.27, self.fp_center, unit=MM))

        self.fp_between = kfp.Footprint.load(res.joinpath('pad-between-spiked.kicad_mod').read_text(encoding='utf-8'))
        self.objects.append(kfp.FootprintInstance(1.27, 0, self.fp_between, unit=MM))
        self.objects.append(kfp.FootprintInstance(0, 1.27, self.fp_between, rotation=math.pi/2, unit=MM))

        self.pad = kfp.Footprint.load(res.joinpath('tht-0.8.kicad_mod').read_text(encoding='utf-8'))
        self.objects.append(kfp.FootprintInstance(0, 0, self.pad, unit=MM))

def convert_to_mm(value, unit):
    unitl  = unit.lower()
    if unitl == 'mm':
        return value
    elif unitl == 'cm':
        return value*10
    elif unitl == 'in':
        return value*25.4
    elif unitl == 'mil':
        return value/1000*25.4
    else:
        raise ValueError(f'Invalid unit {unit}, allowed units are mm, cm, in, and mil.')


_VALUE_RE = re.compile('([0-9]*\.?[0-9]+)(cm|mm|in|mil|%)')
def eval_value(value, total_length=None):
    if not isinstance(value, str):
        return None

    m = _VALUE_RE.match(value.lower())
    number, unit = m.groups()
    if unit == '%':
        if total_length is None:
            raise ValueError('Percentages are not allowed for this value')
        return total_length * float(number) / 100
    return convert_to_mm(float(number), unit)


def _demo():
    #pattern1 = PatternProtoArea(2.54, obj=THTPad.circle(0, 0, 0.9, 1.8, paste=False))
    pattern1 = PatternProtoArea(2.54, 2.54, obj=SpikyProto())
    pattern2 = PatternProtoArea(1.2, 2.0, obj=SMDPad.rect(0, 0, 1.0, 1.8, paste=False))
    pattern3 = PatternProtoArea(2.54, 1.27, obj=SMDPad.rect(0, 0, 2.3, 1.0, paste=False))
    #pattern3 = EmptyProtoArea(copper_fill=True)
    #stack = TwoSideLayout(pattern2, pattern3)
    stack = PropLayout([pattern2, pattern3], 'v', [0.5, 0.5])
    pattern = PropLayout([pattern1, stack], 'h', [0.5, 0.5])
    #pattern = PatternProtoArea(2.54, obj=ManhattanPads(2.54))
    #pattern = PatternProtoArea(2.54, obj=PoweredProto())
    #pattern = PatternProtoArea(2.54, obj=RFGroundProto())
    #pattern = PatternProtoArea(2.54*1.5, obj=THTFlowerProto())
    #pattern = PatternProtoArea(2.54, obj=THTPad.circle(0, 0, 0.9, 1.8, paste=False))
    #pattern = PatternProtoArea(2.54, obj=PoweredProto())
    pb = ProtoBoard(30, 30, pattern1, mounting_hole_dia=3.2, mounting_hole_offset=5)
    print(pb.pretty_svg())
    pb.layer_stack().save_to_directory('/tmp/testdir')


if __name__ == '__main__':
    _demo()
    #cnt = alphabetic()()
    #for _ in range(32):
    #    for _ in range(26):
    #        print(f'{next(cnt):>2}', end=' ', file=sys.stderr)
    #    print(file=sys.stderr)