// Author: fruit.com.cn

import 'package:flutter/material.dart';
import 'package:flutter/services.dart';

import 'app_colors.dart';
import 'app_dimens.dart';

/// Obsidian Flare themes. Dark is the product default; light mirrors the same
/// orange primary for system-light devices.
abstract final class AppTheme {
  static const _lightBackground = Color(0xFFF7F7F8);
  static const _darkBackground = AppColors.ink;

  /// 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.blue,
  );

  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.secondary,
            onSecondary: AppColors.onPrimary,
            primaryContainer: AppColors.bluePressed,
            onPrimaryContainer: AppColors.onPrimary,
            secondaryContainer: AppColors.raised,
            onSecondaryContainer: AppColors.onPrimary,
            surface: _darkBackground,
            onSurface: AppColors.onSurface,
            outline: AppColors.outlineDark,
            outlineVariant: AppColors.outlineVariantDark,
            surfaceTint: AppColors.blue,
            inversePrimary: AppColors.blueSoft,
          )
        : ColorScheme.light(
            primary: AppColors.blue,
            onPrimary: AppColors.onPrimary,
            secondary: AppColors.secondary,
            onSecondary: AppColors.onPrimary,
            primaryContainer: AppColors.blue.withValues(alpha: 0.14),
            onPrimaryContainer: AppColors.ink,
            secondaryContainer: AppColors.blueSoft.withValues(alpha: 0.14),
            onSecondaryContainer: AppColors.ink,
            surface: _lightBackground,
            onSurface: AppColors.ink,
            outline: AppColors.outlineLight,
            outlineVariant: AppColors.outlineVariantLight,
            surfaceTint: AppColors.blue,
            inversePrimary: AppColors.blueSoft,
          );
    final base = ThemeData(
      useMaterial3: true,
      brightness: brightness,
      colorScheme: scheme,
      scaffoldBackgroundColor: surface,
      fontFamily: 'PlusJakartaSans',
      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),
          minimumSize: const WidgetStatePropertyAll(
            Size(0, AppDimens.buttonHeight),
          ),
        ),
      ),
      outlinedButtonTheme: OutlinedButtonThemeData(
        style: ButtonStyle(
          foregroundColor: WidgetStatePropertyAll(
            dark ? AppColors.blueSoft : AppColors.bluePressed,
          ),
          minimumSize: const WidgetStatePropertyAll(
            Size(0, AppDimens.buttonHeight),
          ),
          side: WidgetStatePropertyAll(
            BorderSide(
              color: dark ? AppColors.outlineDark : AppColors.outlineLight,
            ),
          ),
        ),
      ),
      appBarTheme: const AppBarTheme(
        systemOverlayStyle: SystemUiOverlayStyle.light,
        titleTextStyle: TextStyle(
          color: AppColors.onSurface,
          fontFamily: 'Outfit',
          fontSize: AppDimens.pageTitle,
          fontWeight: FontWeight.w800,
        ),
      ),
      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),
      ),
    );
    final textTheme = base.textTheme
        .apply(
          fontFamily: 'PlusJakartaSans',
          bodyColor: dark ? AppColors.cream : AppColors.ink,
          displayColor: dark ? AppColors.onSurface : AppColors.ink,
        )
        .copyWith(
          displayLarge: _display(base.textTheme.displayLarge, dark),
          displayMedium: _display(base.textTheme.displayMedium, dark),
          displaySmall: _display(base.textTheme.displaySmall, dark),
          headlineLarge: _display(base.textTheme.headlineLarge, dark),
          headlineMedium: _display(base.textTheme.headlineMedium, dark),
          headlineSmall: _display(base.textTheme.headlineSmall, dark),
          titleLarge: _display(base.textTheme.titleLarge, dark),
        );
    return base.copyWith(textTheme: textTheme);
  }

  static TextStyle? _display(TextStyle? style, bool dark) => style?.copyWith(
    fontFamily: 'Outfit',
    color: dark ? AppColors.onSurface : AppColors.ink,
  );

  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;
  }
}