# coding: utf-8
"""主题切换回归自检（无窗口, 离屏渲染）。

背景: fluent 控件直接 setStyleSheet 的样式会在 setTheme 时被库重刷的自带 qss 冲掉
（v0.4.0 RGB swatch 按钮切主题丢底色的根因）。swatch 改走 setCustomStyleSheet、
标题字号走 QFont 后，本测试保证:
  1. Dark -> Light -> Dark -> Light 往返后 9 个 swatch 按钮样式表仍带底色；
  2. Light 下实际渲染出的按钮中心像素 = swatch 色值（不只样式表字符串存在）；
  3. 标题 24px 加粗（QFont）在往返后不变。

运行: python selftest_theme.py  （依赖 PySide6-Fluent-Widgets）
"""
import os
import sys

os.environ.setdefault("QT_QPA_PLATFORM", "offscreen")
sys.path.insert(0, os.path.dirname(os.path.abspath(__file__)))

from PySide6.QtGui import QColor
from PySide6.QtWidgets import QApplication
from qfluentwidgets import PushButton, StrongBodyLabel, Theme, setTheme

import app_fluent
import patterns


def check_style_sheet(win, app):
    swatches = [b for b in win.findChildren(PushButton) if b.text() in {"55", "AA", "FF"}]
    assert len(swatches) == 9, f"expect 9 swatch buttons, got {len(swatches)}"
    title = [l for l in win.findChildren(StrongBodyLabel) if l.text() == "DLPilot"]
    assert len(title) == 1, "title label not found"
    colored = sum(1 for b in swatches if "background-color: #" in b.styleSheet())
    f = title[0].font()
    print(f"  swatch 样式表带底色: {colored}/9, 标题 24px 粗体: "
          f"{f.pixelSize() == 24 and f.bold()}")
    return colored == 9 and f.pixelSize() == 24 and f.bold()


def check_rendered_pixel(win, app):
    """Light 主题下逐个渲染 swatch，与目标色一致的像素须占明显多数（背景为主，
    中心处是文字字形，不能只采单点）。"""
    ok = True
    for channel, items in patterns.SOLID_ROWS:
        for label, color in items:
            button = next(b for b in win.findChildren(PushButton)
                          if b.text() == label and f"background-color: {color}" in b.styleSheet())
            image = button.grab().toImage()
            target = QColor(color)
            total, matched = image.width() * image.height(), 0
            for y in range(image.height()):
                for x in range(image.width()):
                    if image.pixelColor(x, y) == target:
                        matched += 1
            ratio = matched / total
            same = ratio >= 0.2
            ok &= same
            if not same:
                print(f"  渲染不符: {channel}/{label} 期望 {color} 仅占 {ratio:.0%}")
    print(f"  Light 下渲染像素比对: {'一致' if ok else '存在偏差'}")
    return ok


def main():
    app = QApplication.instance() or QApplication(sys.argv)
    setTheme(Theme.AUTO)
    win = app_fluent.App(0)
    passed = True
    for step, theme in (("初始 Dark", Theme.DARK), ("切 Light", Theme.LIGHT),
                        ("切回 Dark", Theme.DARK), ("再切 Light", Theme.LIGHT)):
        setTheme(theme)
        app.processEvents()
        print(f"[{step}]")
        passed &= check_style_sheet(win, app)
        if theme == Theme.LIGHT:
            passed &= check_rendered_pixel(win, app)
    win.close()
    print("ALL PASS" if passed else "FAILED")
    return 0 if passed else 1


if __name__ == "__main__":
    sys.exit(main())