// Author: fruit.com.cn

import 'package:flutter/material.dart';

import 'app_colors.dart';

/// App-wide light and dark themes built from the approved Klein Blue palette.
abstract final class AppTheme {
  static const _lightBackground = Color(0xFFF8F7FC);
  static const _darkBackground = Color(0xFF101019);

  /// Light theme for system light mode.
  static ThemeData light() => _build(
    brightness: Brightness.light,
    surface: _lightBackground,
    accent: AppColors.blue,
  );

  /// Dark theme for system dark mode.
  static ThemeData dark() => _build(
    brightness: Brightness.dark,
    surface: _darkBackground,
    accent: AppColors.blueSoft,
  );

  static ThemeData _build({
    required Brightness brightness,
    required Color surface,
    required Color accent,
  }) {
    final dark = brightness == Brightness.dark;
    final scheme = dark
        ? const ColorScheme.dark(
            primary: AppColors.blue,
            onPrimary: AppColors.onPrimary,
            secondary: AppColors.blueSoft,
            onSecondary: AppColors.ink,
            primaryContainer: AppColors.bluePressed,
            onPrimaryContainer: AppColors.onPrimary,
            secondaryContainer: AppColors.bluePressed,
            onSecondaryContainer: AppColors.onPrimary,
            surface: _darkBackground,
            onSurface: Colors.white,
            outline: AppColors.outlineDark,
            outlineVariant: AppColors.outlineVariantDark,
            surfaceTint: AppColors.blueSoft,
            inversePrimary: AppColors.blueSoft,
          )
        : ColorScheme.light(
            primary: AppColors.blue,
            onPrimary: AppColors.onPrimary,
            secondary: AppColors.blue,
            onSecondary: AppColors.onPrimary,
            primaryContainer: AppColors.blueSoft.withValues(alpha: 0.22),
            onPrimaryContainer: AppColors.ink,
            secondaryContainer: AppColors.blueSoft.withValues(alpha: 0.22),
            onSecondaryContainer: AppColors.ink,
            surface: _lightBackground,
            onSurface: AppColors.ink,
            outline: AppColors.outlineLight,
            outlineVariant: AppColors.outlineVariantLight,
            surfaceTint: AppColors.blue,
            inversePrimary: AppColors.blueSoft,
          );
    return ThemeData(
      useMaterial3: true,
      brightness: brightness,
      colorScheme: scheme,
      scaffoldBackgroundColor: surface,
      progressIndicatorTheme: ProgressIndicatorThemeData(color: accent),
      sliderTheme: SliderThemeData(
        activeTrackColor: accent,
        thumbColor: AppColors.onPrimary,
      ),
      tabBarTheme: TabBarThemeData(labelColor: accent, indicatorColor: accent),
      textButtonTheme: TextButtonThemeData(
        style: TextButton.styleFrom(foregroundColor: accent),
      ),
      filledButtonTheme: FilledButtonThemeData(
        style: ButtonStyle(
          backgroundColor: WidgetStateProperty.resolveWith(_buttonColor),
          foregroundColor: const WidgetStatePropertyAll(AppColors.onPrimary),
        ),
      ),
      switchTheme: SwitchThemeData(
        thumbColor: WidgetStateProperty.resolveWith(
          (states) => states.contains(WidgetState.selected)
              ? AppColors.onPrimary
              : null,
        ),
        trackColor: WidgetStateProperty.resolveWith(
          (states) => states.contains(WidgetState.selected) ? accent : null,
        ),
      ),
      snackBarTheme: SnackBarThemeData(
        backgroundColor: AppColors.bluePressed,
        contentTextStyle: const TextStyle(color: AppColors.onPrimary),
      ),
    );
  }

  static Color _buttonColor(Set<WidgetState> states) {
    if (states.contains(WidgetState.pressed) ||
        states.contains(WidgetState.hovered) ||
        states.contains(WidgetState.focused)) {
      return AppColors.bluePressed;
    }
    return AppColors.blue;
  }
}