"""通知卡片渲染测试：版式、场景徽章、中文/Emoji 折行与降级路径。"""
import base64
import importlib.util
import io
from pathlib import Path

from PIL import Image, ImageDraw


def load_image_renderer():
	"""按路径加载渲染模块，避免拉起需要 NoneBot 初始化的插件包。"""
	path = Path(__file__).resolve().parents[1] / "danding_bot" / "plugins" / "danding_qqpush" / "image_render.py"
	spec = importlib.util.spec_from_file_location("danding_qqpush_image_render", path)
	module = importlib.util.module_from_spec(spec)
	spec.loader.exec_module(module)
	return module


def build_renderer(module, **kwargs):
	return module.ImageRenderer(**kwargs)


def install_offline_pilmoji(monkeypatch, module):
	"""用不访问远程 Emoji 源的替身，保证 Emoji 相关渲染测试离线可跑。"""

	class OfflinePilmoji:
		def __init__(self, image):
			self._draw = ImageDraw.Draw(image)

		def __enter__(self):
			return self

		def __exit__(self, *args):
			return False

		def text(self, xy, text, font=None, fill=None, **kwargs):
			self._draw.text(xy, text, font=font, fill=fill)

	monkeypatch.setattr(module, "Pilmoji", OfflinePilmoji)


def open_png(data: bytes) -> Image.Image:
	return Image.open(io.BytesIO(data)).convert("RGB")


def ink_bbox(image: Image.Image, box=None):
	"""返回区域内墨迹（暗色像素）的包围盒，用于判断是否越界。"""
	region = image.crop(box) if box else image
	mask = region.convert("L").point(lambda value: 255 if value < 200 else 0)
	return mask.getbbox()


def ink_pixels(image: Image.Image, box=None) -> int:
	"""区域内墨迹像素数量，用于比较某块区域是否新增了文字。"""
	region = image.crop(box) if box else image
	mask = region.convert("L").point(lambda value: 255 if value < 200 else 0)
	return mask.histogram()[255]


def first_ink_row(image: Image.Image, y_from: int, margin: int) -> int:
	"""自 y_from 起逐行扫描，返回第一行存在墨迹的 y 坐标。"""
	for y in range(y_from, image.size[1] - 1):
		if ink_pixels(image, (margin, y, image.size[0] - margin, y + 1)) > 0:
			return y
	raise AssertionError("区域下方未找到任何墨迹")


def header_bottom(image: Image.Image, margin: int, brand_color) -> int:
	"""沿水平中线向下找到蓝色头部结束的位置。"""
	width, height = image.size
	pixels = image.load()
	for y in range(margin, height):
		if pixels[width // 2, y] != brand_color:
			return y
	raise AssertionError("未找到品牌头部下边界")


def color_count(image: Image.Image, box, color) -> int:
	colors = image.crop(box).getcolors(maxcolors=image.size[0] * image.size[1])
	return dict((pixel, count) for count, pixel in colors).get(color, 0)


def content_limits(renderer, width: int = 800):
	margin = renderer.OUTER_MARGIN
	card_right = width - margin
	return margin + renderer.padding, card_right - renderer.padding


def badge_rows(renderer, width: int = 800):
	"""按与 render() 一致的版式计算白色徽章胶囊的范围与宽度。

	返回 (badge_top, badge_bottom, badge_width, header_bottom)，均为图像绝对坐标。
	"""
	margin = renderer.OUTER_MARGIN
	brand_font = renderer._load_font_by_size(max(int(renderer.font_size * 1.05), 12))
	badge_font = renderer._load_font_by_size(max(int(renderer.font_size * 0.8), 11))

	badge_text = str(renderer.SCENE_STYLES["common"]["label"])
	badge_text_height = renderer._text_size(badge_text, badge_font)[1]
	badge_height = badge_text_height + 2 * max(int(renderer.font_size * 0.25), 4)
	badge_width = int(renderer._measure_text(badge_text, badge_font)) + 2 * max(int(renderer.font_size * 0.6), 10)
	header_height = max(renderer._text_size(renderer.BRAND_LABEL, brand_font)[1], badge_height) + 2 * max(int(renderer.font_size * 0.65), 12)
	badge_top = margin + max((header_height - badge_height) // 2, 0)
	return badge_top, badge_top + badge_height - 1, badge_width, margin + header_height


def badge_bounds(renderer, width: int = 800):
	"""用 render() 的同一公式推出徽章胶囊的水平范围，返回 (badge_left, badge_right)。

	卡片底色本身就是白色，因此不能靠“整行扫白”定位胶囊（会把卡片底色一起扫进来），
	这里直接按版式公式定位：徽章右边缘贴合内容右边界，宽度由文字宽度加左右内边距决定。
	"""
	margin = renderer.OUTER_MARGIN
	card_right = width - margin
	_, _, badge_width, _ = badge_rows(renderer, width)
	badge_left = card_right - renderer.padding - badge_width
	return badge_left, badge_left + badge_width - 1


def accent_ink_bounds(image: Image.Image, box, color, tolerance: int = 45):
	"""返回框内场景强调色像素的绝对包围盒，即徽章文字的可见墨迹（白底不会算作文字）。

	搜索范围只覆盖白色胶囊内部，因此不会误把头部品牌蓝当作 emphasis 色。
	"""
	left, top, right, bottom = box
	clipped = image.crop((left, top, right + 1, bottom + 1))
	pixels = clipped.load()
	xs, ys = [], []
	for y in range(clipped.size[1]):
		for x in range(clipped.size[0]):
			pixel = pixels[x, y]
			if all(abs(pixel[index] - color[index]) <= tolerance for index in range(3)):
				xs.append(left + x)
				ys.append(top + y)
	if not xs:
		raise AssertionError("未在徽章内找到场景强调色文字墨迹")
	return min(xs), min(ys), max(xs), max(ys)


def test_render_keeps_legacy_calls_working():
	module = load_image_renderer()
	renderer = build_renderer(module)

	png = renderer.render("系统告警")
	assert png.startswith(b"\x89PNG")

	encoded = renderer.render_to_base64("系统告警")
	assert encoded.startswith("base64://")
	assert base64.b64decode(encoded[len("base64://"):]) == png

	# 历史调用方式（位置参数传 title）依然可用
	assert renderer.render("系统告警", "自定义标题").startswith(b"\x89PNG")
	assert renderer.render_to_base64("系统告警", title="自定义标题").startswith("base64://")


def test_card_uses_cool_gray_backdrop_and_blue_brand_header():
	module = load_image_renderer()
	renderer = build_renderer(module)
	renderer_class = module.ImageRenderer

	image = open_png(renderer.render("卡片版式校验", scene="group"))
	width, height = image.size
	margin = renderer_class.OUTER_MARGIN

	assert width == renderer.width == 800
	assert image.getpixel((2, 2)) == renderer_class.OUTER_BG_COLOR
	assert image.getpixel((width - 3, height - 3)) == renderer_class.OUTER_BG_COLOR
	assert image.getpixel((width // 2, margin + 5)) == renderer_class.BRAND_COLOR
	assert image.getpixel((width // 2, height - margin - 5)) == renderer.bg_color


def test_scene_badges_distinguish_group_and_private_notifications():
	module = load_image_renderer()
	renderer = build_renderer(module)

	common = renderer.render("同一段通知内容", scene="common")
	group = renderer.render("同一段通知内容", scene="group")
	private = renderer.render("同一段通知内容", scene="private")

	assert len({common, group, private}) == 3

	margin = renderer.OUTER_MARGIN
	header_box = (margin, margin, 800 - margin, margin + 80)
	private_image = open_png(private)
	common_image = open_png(common)

	# 徽章为白色胶囊，文字使用场景强调色
	assert color_count(private_image, header_box, renderer.BADGE_BG_COLOR) > 200
	assert color_count(private_image, header_box, renderer.SCENE_STYLES["private"]["color"]) > 0
	assert color_count(common_image, header_box, renderer.SCENE_STYLES["common"]["color"]) > 0
	assert color_count(common_image, header_box, renderer.SCENE_STYLES["private"]["color"]) == 0


def test_unknown_scene_falls_back_to_common_style():
	module = load_image_renderer()
	renderer = build_renderer(module)

	assert renderer._scene_style("group")["label"] == "群聊通知"
	assert renderer._scene_style("private")["label"] == "私聊通知"

	unknown = renderer._scene_style("nope")
	assert unknown["label"] == renderer.SCENE_STYLES[renderer.DEFAULT_SCENE]["label"]
	assert unknown["color"] == renderer.SCENE_STYLES[renderer.DEFAULT_SCENE]["color"]

	assert renderer.render("未知场景", scene="nope") == renderer.render("未知场景", scene="common")


def test_long_text_wraps_without_leaving_the_card():
	module = load_image_renderer()
	renderer = build_renderer(module)

	content_left, content_right = content_limits(renderer)
	content_width = content_right - content_left

	lines = renderer._wrap_text("超长文本测试，" * 200, content_width)
	assert all(renderer._measure_text(line, renderer.font) <= content_width for line in lines)
	assert "".join(lines) == "超长文本测试，" * 200

	image = open_png(renderer.render("超长文本测试，" * 200, scene="group"))
	width, height = image.size
	margin = renderer.OUTER_MARGIN
	header_end = header_bottom(image, margin, renderer.BRAND_COLOR)
	body_box = (margin, header_end + 1, width - margin, height - margin)

	left, top, right, bottom = ink_bbox(image, body_box)
	absolute = (body_box[0] + left, body_box[1] + top, body_box[0] + right, body_box[1] + bottom)
	assert absolute[0] >= content_left
	assert absolute[2] <= content_right
	assert absolute[3] < height - margin


def test_explicit_newlines_and_blank_lines_are_preserved():
	module = load_image_renderer()
	renderer = build_renderer(module)
	content_left, content_right = content_limits(renderer)

	lines = renderer._wrap_text("第一行\n第二行\n\n第四行", content_right - content_left)

	assert lines == ["第一行", "第二行", "", "第四行"]


def test_cjk_punctuation_does_not_start_or_end_a_line():
	module = load_image_renderer()
	renderer = build_renderer(module)
	content_left, content_right = content_limits(renderer)
	content_width = content_right - content_left

	cases = [
		# 28 个全角汉字正好铺满一行，逗号会落在下一行行首
		"甲" * 28 + "，后续内容" + "乙" * 26 + "（括号内容）",
		# 27 个汉字加左括号刚好占满，右括号内容会被挤到下一行，左括号不能留在行尾
		"甲" * 27 + "（乙" * 20,
	]

	for text in cases:
		lines = renderer._wrap_text(text, content_width)

		assert "".join(lines) == text
		for line in lines:
			if line:
				assert line[0] not in module.ImageRenderer.LINE_START_FORBIDDEN
				assert renderer._measure_text(line, renderer.font) <= content_width
		for line in lines[:-1]:
			assert line[-1] not in module.ImageRenderer.LINE_END_FORBIDDEN


def test_emoji_is_measured_as_square_and_kept_whole():
	module = load_image_renderer()
	renderer = build_renderer(module)

	atoms = list(renderer._iter_atoms("🏇出发", renderer.font))
	assert atoms[0][0] == "🏇"
	assert atoms[0][1] == renderer.font.size

	# ZWJ 组合、肤色修饰、区域指示符组合都不应被拆开
	family, flag = "👨‍👩‍👧", "🇨🇳"
	atoms = list(renderer._iter_atoms(f"👍🏻{family}{flag}赞", renderer.font))
	groups = [atom for atom, _ in atoms]
	assert "👍🏻" in groups
	assert family in groups
	assert flag in groups


def test_emoji_text_does_not_overflow_the_card(monkeypatch):
	module = load_image_renderer()
	install_offline_pilmoji(monkeypatch, module)
	renderer = build_renderer(module)

	content_left, content_right = content_limits(renderer)
	content_width = content_right - content_left

	text = "🏇🎉😀 中文与 Emoji 混排的长通知，" * 20
	lines = renderer._wrap_text(text, content_width)
	assert "".join(lines) == text
	assert all(renderer._measure_text(line, renderer.font) <= content_width for line in lines)

	image = open_png(renderer.render(text, scene="group"))
	width, height = image.size
	margin = renderer.OUTER_MARGIN
	header_end = header_bottom(image, margin, renderer.BRAND_COLOR)
	body_box = (margin, header_end + 1, width - margin, height - margin)
	left, _, right, _ = ink_bbox(image, body_box)
	assert body_box[0] + left >= content_left
	assert body_box[0] + right <= content_right


def test_body_line_height_is_at_least_one_point_six(monkeypatch):
	module = load_image_renderer()
	renderer = build_renderer(module, line_spacing=1.2)

	single = open_png(renderer.render("单行"))
	double = open_png(renderer.render("第一行\n第二行"))
	line_height = double.size[1] - single.size[1]

	assert line_height > 0
	assert line_height >= int(renderer._text_size("测试", renderer.font)[1] * 1.6)


def test_default_title_keeps_legacy_text_and_none_hides_it(monkeypatch):
	"""默认标题沿用旧版文案（向后兼容），显式 None / 空字符串才隐藏标题行。"""
	module = load_image_renderer()
	install_offline_pilmoji(monkeypatch, module)
	renderer = build_renderer(module)

	assert module.ImageRenderer.DEFAULT_TITLE == "蛋定助手通知您："

	default_image = open_png(renderer.render("正文内容"))
	hidden_image = open_png(renderer.render("正文内容", title=None))
	empty_image = open_png(renderer.render("正文内容", title=""))
	custom_image = open_png(renderer.render("正文内容", title="🏇 赛马开赛"))

	# 默认渲染比显式隐藏多一行标题
	assert default_image.size[1] > hidden_image.size[1]
	# 显式 None 与空字符串等效，且自定义单行标题与默认标题高度一致
	assert hidden_image.size[1] == empty_image.size[1]
	assert custom_image.size[1] == default_image.size[1]

	# 默认渲染在头部下方先画标题行，显式隐藏时同一位置直接是正文
	margin = renderer.OUTER_MARGIN
	header_end = header_bottom(default_image, margin, module.ImageRenderer.BRAND_COLOR)
	top_band = (
		margin,
		header_end + renderer.padding + 1,
		default_image.size[0] - margin,
		header_end + renderer.padding + 40,
	)
	default_band = ink_bbox(default_image, top_band)
	hidden_band = ink_bbox(hidden_image, top_band)

	assert default_band is not None and hidden_band is not None
	# 隐藏标题时正文紧贴头部内边距开始
	assert first_ink_row(hidden_image, header_end + 1, margin) >= header_end + renderer.padding
	# 标题「蛋定助手通知您：」明显宽于正文「正文内容」，据此确认标题行确实绘制了
	assert (default_band[2] - default_band[0]) > (hidden_band[2] - hidden_band[0]) * 1.5

	# render_to_base64 同样继承默认标题文案
	encoded = renderer.render_to_base64("正文内容")
	assert open_png(base64.b64decode(encoded[len("base64://"):])).size == default_image.size


def test_badge_text_ink_is_vertically_centered_in_the_capsule():
	"""回归：徽章文字的可见墨迹应在白色胶囊内垂直居中，而非按字体 metrics 偏下。"""
	module = load_image_renderer()
	renderer = build_renderer(module)
	badge_top, badge_bottom, badge_width, _ = badge_rows(renderer)
	badge_left, badge_right = badge_bounds(renderer)

	# 版式算法自身的一致性：胶囊右边缘贴合内容右边界，宽度由文字加内边距构成
	assert badge_left == (800 - renderer.OUTER_MARGIN) - renderer.padding - badge_width
	assert badge_right - badge_left + 1 == badge_width

	for scene in ("group", "private", "common"):
		label = str(renderer.SCENE_STYLES[scene]["label"])
		color = tuple(renderer.SCENE_STYLES[scene]["color"])
		image = open_png(renderer.render("同一段通知内容", scene=scene))

		# 用像素确认胶囊确实落在算出来的水平范围内：胶囊内部为白色，左右外侧仍是头部品牌蓝
		center_y = (badge_top + badge_bottom) // 2
		assert image.getpixel((badge_left + 2, center_y)) == renderer.BADGE_BG_COLOR, scene
		assert image.getpixel((badge_right - 2, center_y)) == renderer.BADGE_BG_COLOR, scene
		assert image.getpixel((badge_left - 2, center_y)) == renderer.BRAND_COLOR, scene
		assert image.getpixel((badge_right + 2, center_y)) == renderer.BRAND_COLOR, scene

		# 文字搜索范围收在胶囊中段的矩形区：胶囊本身是圆角，顶/底行中段藏有圆角，
		# 而圆角处仍是头部品牌蓝，会和 group 场景的强调色混淆；左右也避开圆角留白。
		corner_inset = (badge_bottom - badge_top + 1) // 2
		text_box = (
			badge_left + corner_inset,
			badge_top,
			badge_right - corner_inset,
			badge_bottom,
		)
		ink_left, ink_top, ink_right, ink_bottom = accent_ink_bounds(image, text_box, color)
		top_gap = ink_top - badge_top
		bottom_gap = badge_bottom - ink_bottom

		# 文字墨迹留在胶囊内（左右不越界），且上下留白基本相等（1-2 像素内视为居中）
		assert badge_left < ink_left and ink_right < badge_right, (scene, label, ink_left, ink_right)
		assert 0 < top_gap <= (badge_bottom - badge_top + 1) // 2, (scene, label, top_gap)
		assert 0 < bottom_gap <= (badge_bottom - badge_top + 1) // 2, (scene, label, bottom_gap)
		assert abs(top_gap - bottom_gap) <= 2, (scene, label, top_gap, bottom_gap)


def test_badge_text_origin_matches_the_painted_ink_center():
	"""回归：_vertical_text_origin 返回的原点能让 textbbox 墨迹中点落在徽章中心线上。"""
	module = load_image_renderer()
	renderer = build_renderer(module)
	badge_font = renderer._load_font_by_size(max(int(renderer.font_size * 0.8), 11))
	center_y = 200

	for scene in ("group", "private", "common"):
		label = str(renderer.SCENE_STYLES[scene]["label"])
		origin_y = renderer._vertical_text_origin(center_y, label, badge_font)
		bbox = renderer._get_measuring_draw().textbbox((0, origin_y), label, font=badge_font)

		assert abs((bbox[1] + bbox[3]) / 2 - center_y) <= 0.5
		# 直接以该原点绘制，真实墨迹中点同样贴近中心线
		canvas = Image.new("RGB", (200, 400), (255, 255, 255))
		ImageDraw.Draw(canvas).text((0, origin_y), label, font=badge_font, fill=tuple(renderer.SCENE_STYLES[scene]["color"]))
		left, top, right, bottom = accent_ink_bounds(canvas, (0, 0, 199, 399), tuple(renderer.SCENE_STYLES[scene]["color"]))
		assert abs((top + bottom) / 2 - center_y) <= 1.5


def test_empty_text_keeps_placeholder_and_minimum_height():
	module = load_image_renderer()
	renderer = build_renderer(module)

	image = open_png(renderer.render(""))
	margin = renderer.OUTER_MARGIN
	header_end = header_bottom(image, margin, renderer.BRAND_COLOR)
	body_box = (margin, header_end + 1, image.size[0] - margin, image.size[1] - margin)

	assert image.size[1] >= module.ImageRenderer.MIN_HEIGHT
	assert ink_bbox(image, body_box) is not None


def test_render_falls_back_to_plain_text_when_emoji_source_fails(monkeypatch):
	module = load_image_renderer()
	renderer = build_renderer(module)

	class BrokenPilmoji:
		def __init__(self, image):
			self.image = image

		def __enter__(self):
			return self

		def __exit__(self, *args):
			return False

		def text(self, *args, **kwargs):
			raise RuntimeError("emoji 源不可用")

	monkeypatch.setattr(module, "Pilmoji", BrokenPilmoji)

	png = renderer.render("降级测试 🏇", scene="private")

	assert png.startswith(b"\x89PNG")
	assert renderer._emoji_enabled is False


def test_pure_black_text_color_falls_back_to_soft_ink():
	module = load_image_renderer()

	assert build_renderer(module, text_color=(0, 0, 0)).text_color == module.ImageRenderer.DEFAULT_TEXT_COLOR
	assert build_renderer(module, text_color=(10, 20, 30)).text_color == (10, 20, 30)
	assert module.ImageRenderer.DEFAULT_TEXT_COLOR != (0, 0, 0)