"""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 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_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)