#! /usr/bin/env python
# -*- coding: utf-8 -*-
# Author: Jan Götte <code@jaseg.de>
import math

from PIL import Image
import pytest

from ..rs274x import GerberFile
from ..cam import FileSettings

from .image_support import *
from .utils import *

REFERENCE_FILES = [ l.strip() for l in '''
    board_outline.GKO
    example_outline_with_arcs.gbr
    example_two_square_boxes.gbr
    example_coincident_hole.gbr
    example_cutin.gbr
    example_cutin_multiple.gbr
    example_flash_circle.gbr
    example_flash_obround.gbr
    example_flash_polygon.gbr
    example_flash_rectangle.gbr
    example_fully_coincident.gbr
    example_guess_by_content.g0
    example_holes_dont_clear.gbr
    example_level_holes.gbr
    example_not_overlapping_contour.gbr
    example_not_overlapping_touching.gbr
    example_overlapping_contour.gbr
    example_overlapping_touching.gbr
    example_simple_contour.gbr
    example_single_contour_1.gbr
    example_single_contour_2.gbr
    example_single_contour_3.gbr
    example_am_exposure_modifier.gbr
    bottom_copper.GBL
    bottom_mask.GBS
    bottom_silk.GBO
    eagle_files/copper_bottom_l4.gbr
    eagle_files/copper_inner_l2.gbr
    eagle_files/copper_inner_l3.gbr
    eagle_files/copper_top_l1.gbr
    eagle_files/profile.gbr
    eagle_files/silkscreen_bottom.gbr
    eagle_files/silkscreen_top.gbr
    eagle_files/soldermask_bottom.gbr
    eagle_files/soldermask_top.gbr
    eagle_files/solderpaste_bottom.gbr
    eagle_files/solderpaste_top.gbr
    multiline_read.ger
    test_fine_lines_x.gbr
    test_fine_lines_y.gbr
    top_copper.GTL
    top_mask.GTS
    top_silk.GTO
'''.splitlines() if l ]

MIN_REFERENCE_FILES = [
    'example_two_square_boxes.gbr',
    'example_outline_with_arcs.gbr',
    'example_flash_circle.gbr',
    'example_flash_polygon.gbr',
    'example_flash_rectangle.gbr',
    'example_simple_contour.gbr',
    'example_am_exposure_modifier.gbr',
    'bottom_copper.GBL',
    'bottom_silk.GBO',
    'eagle_files/copper_bottom_l4.gbr'
    ]

HAS_ZERO_SIZE_APERTURES = [
    'bottom_copper.GBL',
    'bottom_silk.GBO',
    'top_copper.GTL',
    'top_silk.GTO',
    'board_outline.GKO',
    'eagle_files/silkscreen_top.gbr',
    ]


@filter_syntax_warnings
@pytest.mark.parametrize('reference', REFERENCE_FILES, indirect=True)
def test_round_trip(reference, tmpfile):
    tmp_gbr = tmpfile('Output gerber', '.gbr')

    GerberFile.open(reference).save(tmp_gbr)

    mean, _max, hist = gerber_difference(reference, tmp_gbr, diff_out=tmpfile('Difference', '.png'))
    assert mean < 5e-5
    assert hist[9] == 0
    assert hist[3:].sum() < 5e-5*hist.size

TEST_ANGLES = [90, 180, 270, 30, 1.5, 10, 360, 1024, -30, -90]
TEST_OFFSETS = [(0, 0), (100, 0), (0, 100), (2, 0), (10, 100)]

@filter_syntax_warnings
@pytest.mark.parametrize('reference', MIN_REFERENCE_FILES, indirect=True)
@pytest.mark.parametrize('angle', TEST_ANGLES)
def test_rotation(reference, angle, tmpfile):
    if 'flash_rectangle' in str(reference) and angle == 1024:
        # gerbv's rendering of this is broken, the hole is missing.
        pytest.skip()

    tmp_gbr = tmpfile('Output gerber', '.gbr')

    f = GerberFile.open(reference)
    f.rotate(math.radians(angle))
    f.save(tmp_gbr)

    cx, cy = 0, to_gerbv_svg_units(10, unit='inch')
    mean, _max, hist = gerber_difference(reference, tmp_gbr, diff_out=tmpfile('Difference', '.png'),
            svg_transform=f'rotate({angle} {cx} {cy})')
    assert mean < 1e-3 # relax mean criterion compared to above.
    assert hist[9] == 0

@filter_syntax_warnings
@pytest.mark.parametrize('reference', MIN_REFERENCE_FILES, indirect=True)
@pytest.mark.parametrize('angle', TEST_ANGLES)
@pytest.mark.parametrize('center', [(0, 0), (-10, -10), (10, 10), (10, 0), (0, -10), (-10, 10), (10, 20)])
def test_rotation_center(reference, angle, center, tmpfile):
    if 'flash_rectangle' in str(reference) and angle in (30, 1024):
        # gerbv's rendering of this is broken, the hole is missing.
        pytest.skip()

    tmp_gbr = tmpfile('Output gerber', '.gbr')

    f = GerberFile.open(reference)
    f.rotate(math.radians(angle), center=center)
    f.save(tmp_gbr)

    # calculate circle center in SVG coordinates 
    size = (10, 10) # inches
    cx, cy = to_gerbv_svg_units(center[0]), to_gerbv_svg_units(size[1], 'inch')-to_gerbv_svg_units(center[1], 'mm')
    mean, _max, hist = gerber_difference(reference, tmp_gbr, diff_out=tmpfile('Difference', '.png'),
            svg_transform=f'rotate({angle} {cx} {cy})',
            size=size)
    assert mean < 1e-3
    assert hist[9] < 50
    assert hist[3:].sum() < 1e-3*hist.size

@filter_syntax_warnings
@pytest.mark.parametrize('reference', MIN_REFERENCE_FILES, indirect=True)
@pytest.mark.parametrize('offset', TEST_OFFSETS)
def test_offset(reference, offset, tmpfile):
    tmp_gbr = tmpfile('Output gerber', '.gbr')

    f = GerberFile.open(reference)
    f.offset(*offset)
    f.save(tmp_gbr, settings=FileSettings(unit=f.unit, number_format=(4,7)))

    # flip y offset since svg's y axis is flipped compared to that of gerber
    dx, dy = to_gerbv_svg_units(offset[0]), -to_gerbv_svg_units(offset[1])
    mean, _max, hist = gerber_difference(reference, tmp_gbr, diff_out=tmpfile('Difference', '.png'),
            svg_transform=f'translate({dx} {dy})')
    assert mean < 1e-4
    assert hist[9] == 0

@filter_syntax_warnings
@pytest.mark.parametrize('reference', MIN_REFERENCE_FILES, indirect=True)
@pytest.mark.parametrize('angle', TEST_ANGLES)
@pytest.mark.parametrize('center', [(0, 0), (10, 0), (0, -10), (10, 20)])
@pytest.mark.parametrize('offset', [(0, 0), (100, 0), (0, 100), (100, 100), (100, 10)])
def test_combined(reference, angle, center, offset, tmpfile):
    if 'flash_rectangle' in str(reference) and angle in (30, 1024):
        # gerbv's rendering of this is broken, the hole is missing.
        pytest.skip()

    tmp_gbr = tmpfile('Output gerber', '.gbr')

    f = GerberFile.open(reference)
    f.rotate(math.radians(angle), center=center)
    f.offset(*offset)
    f.save(tmp_gbr, settings=FileSettings(unit=f.unit, number_format=(4,7)))

    size = (10, 10) # inches
    cx, cy = to_gerbv_svg_units(center[0]), to_gerbv_svg_units(size[1], 'inch')-to_gerbv_svg_units(center[1], 'mm')
    dx, dy = to_gerbv_svg_units(offset[0]), -to_gerbv_svg_units(offset[1])
    mean, _max, hist = gerber_difference(reference, tmp_gbr, diff_out=tmpfile('Difference', '.png'),
            svg_transform=f'translate({dx} {dy}) rotate({angle} {cx} {cy})',
            size=size)
    assert mean < 1e-3
    assert hist[9] < 100
    assert hist[3:].sum() < 1e-3*hist.size

@filter_syntax_warnings
@pytest.mark.parametrize('file_a', MIN_REFERENCE_FILES)
@pytest.mark.parametrize('file_b', [
    'example_two_square_boxes.gbr',
    'example_outline_with_arcs.gbr',
    'example_am_exposure_modifier.gbr',
    'bottom_silk.GBO',
    'eagle_files/copper_bottom_l4.gbr', ])
@pytest.mark.parametrize('angle', [0, 10, 90])
@pytest.mark.parametrize('offset', [(0, 0, 0, 0), (100, 0, 0, 0), (0, 0, 0, 100), (100, 0, 0, 100)])
def test_compositing(file_a, file_b, angle, offset, tmpfile, print_on_error):

    # TODO bottom_silk.GBO renders incorrectly with gerbv: the outline does not exist in svg. In GUI, the logo only
    # renders at very high magnification. Skip, and once we have our own SVG export maybe use that instead. Or just use
    # KiCAD's gerbview.
    # TODO check if this and the issue with aperture holes not rendering in test_combined actually are bugs in gerbv
    # and fix/report upstream.
    if file_a == 'bottom_silk.GBO' or file_b == 'bottom_silk.GBO':
        pytest.skip()

    ref_a = reference_path(file_a)
    print_on_error('Reference file a:', ref_a)
    ref_b = reference_path(file_b)
    print_on_error('Reference file b:', ref_b)

    ax, ay, bx, by = offset
    grb_a = GerberFile.open(ref_a)
    grb_a.rotate(math.radians(angle))
    grb_a.offset(ax, ay)

    grb_b = GerberFile.open(ref_b)
    grb_b.offset(bx, by)

    grb_a.merge(grb_b)
    tmp_gbr = tmpfile('Output gerber', '.gbr')
    grb_a.save(tmp_gbr, settings=FileSettings(unit=grb_a.unit, number_format=(4,7)))

    size = (10, 10) # inches
    ax, ay = to_gerbv_svg_units(ax), -to_gerbv_svg_units(ay)
    bx, by = to_gerbv_svg_units(bx), -to_gerbv_svg_units(by)
    # note that we have to specify cx, cy even if we rotate around the origin since gerber's origin lies at (x=0
    # y=+document size) in SVG's coordinate space because svg's y axis is flipped compared to gerber's.
    cx, cy = 0, to_gerbv_svg_units(size[1], 'inch')
    mean, _max, hist = gerber_difference_merge(ref_a, ref_b, tmp_gbr,
            composite_out=tmpfile('Composite', '.svg'), diff_out=tmpfile('Difference', '.png'),
            svg_transform1=f'translate({ax} {ay}) rotate({angle} {cx} {cy})',
            svg_transform2=f'translate({bx} {by})',
            size=size)
    assert mean < 1e-3
    assert hist[9] < 100
    assert hist[3:].sum() < 1e-3*hist.size

@filter_syntax_warnings
@pytest.mark.parametrize('reference', REFERENCE_FILES, indirect=True)
def test_svg_export(reference, tmpfile):

    grb = GerberFile.open(reference)

    bounds = (0.0, 0.0), (6.0, 6.0) # bottom left, top right

    out_svg = tmpfile('Output', '.svg')
    with open(out_svg, 'w') as f:
        f.write(str(grb.to_svg(force_bounds=bounds, arg_unit='inch', color='white')))

    # NOTE: Instead of having gerbv directly export a PNG, we ask gerbv to output SVG which we then rasterize using
    # resvg. We have to do this since gerbv's built-in cairo-based PNG export has severe aliasing issues. In contrast,
    # using resvg for both allows an apples-to-apples comparison of both results.
    ref_svg = tmpfile('Reference export', '.svg')
    ref_png = tmpfile('Reference render', '.png')
    gerbv_export(reference, ref_svg, origin=bounds[0], size=bounds[1])
    svg_to_png(ref_svg, ref_png, dpi=72) # make dpi match Cairo's default

    out_png = tmpfile('Output render', '.png')
    svg_to_png(out_svg, out_png, dpi=72) # make dpi match Cairo's default

    mean, _max, hist = image_difference(ref_png, out_png, diff_out=tmpfile('Difference', '.png'))
    assert mean < 1e-3
    assert hist[9] < 1
    assert hist[3:].sum() < 1e-3*hist.size

# FIXME test svg margin, bounding box computation

@filter_syntax_warnings
@pytest.mark.parametrize('reference', REFERENCE_FILES, indirect=True)
def test_bounding_box(reference, tmpfile):
    # skip this check on files that contain lines with a zero-size aperture at the board edge
    if any(reference.match(f'*/{f}') for f in HAS_ZERO_SIZE_APERTURES):
        pytest.skip()

    # skip this file because it does not contain any graphical objects
    if reference.match('*/multiline_read.ger'):
        pytest.skip()

    margin = 1.0 # inch
    dpi = 200
    margin_px = int(dpi*margin) # intentionally round down to avoid aliasing artifacts

    grb = GerberFile.open(reference)
    out_svg = tmpfile('Output', '.svg')
    with open(out_svg, 'w') as f:
        f.write(str(grb.to_svg(margin=margin, arg_unit='inch', color='white')))

    out_png = tmpfile('Render', '.png')
    svg_to_png(out_svg, out_png, dpi=dpi)

    img = np.array(Image.open(out_png))
    img = img[:, :, :3].mean(axis=2) # drop alpha and convert to grayscale
    img = np.round(img).astype(int) # convert to int
    assert (img > 0).any() # there must be some content, none of the test gerbers are completely empty.
    cols = img.sum(axis=1)
    rows = img.sum(axis=0)
    col_prefix, col_suffix = np.argmax(cols > 0), np.argmax(cols[::-1] > 0)
    row_prefix, row_suffix = np.argmax(rows > 0), np.argmax(rows[::-1] > 0)

    # Check that all margins are completely black and that the content touches the margins. Allow for some tolerance to
    # allow for antialiasing artifacts.
    assert margin_px-1 <= col_prefix <= margin_px+1
    assert margin_px-1 <= col_suffix <= margin_px+1
    assert margin_px-1 <= row_prefix <= margin_px+1
    assert margin_px-1 <= row_suffix <= margin_px+1