bharat_erp/lib/core/theme/app_theme.dart

import 'package:flutter/material.dart';

import 'app_colors.dart';
import 'app_typography.dart';
import 'branding_config.dart';

class AppTheme {
  AppTheme._();

  static ThemeData light({BrandingConfig? branding}) {
    final primary = branding?.primaryColor ?? AppColors.primary;
    final secondary = branding?.secondaryColor ?? AppColors.secondary;

    final colorScheme = ColorScheme.fromSeed(
      seedColor: primary,
      secondary: secondary,
      brightness: Brightness.light,
      surface: AppColors.lightSurface,
    );

    return _buildTheme(colorScheme, Brightness.light);
  }

  static ThemeData dark({BrandingConfig? branding}) {
    final primary = branding?.primaryColor ?? AppColors.primary;
    final secondary = branding?.secondaryColor ?? AppColors.secondary;

    final colorScheme = ColorScheme.fromSeed(
      seedColor: primary,
      secondary: secondary,
      brightness: Brightness.dark,
      surface: AppColors.darkSurface,
    );

    return _buildTheme(colorScheme, Brightness.dark);
  }

  /// Theme for white cards, form fields, and picker sheets (unchanged in dark mode).
  static ThemeData cardContentTheme(ThemeData theme) {
    final scheme = theme.brightness == Brightness.light
        ? theme.colorScheme
        : ColorScheme.fromSeed(
            seedColor: theme.colorScheme.primary,
            secondary: theme.colorScheme.secondary,
            brightness: Brightness.light,
            surface: AppColors.card,
          );

    final base = theme.brightness == Brightness.light
        ? theme
        : theme.copyWith(
            brightness: Brightness.light,
            colorScheme: scheme,
            textTheme: AppTypography.textTheme(scheme),
            primaryTextTheme: AppTypography.textTheme(scheme),
          );

    return base.copyWith(
      scaffoldBackgroundColor: AppColors.card,
      inputDecorationTheme: whiteInputDecorationTheme(scheme),
      bottomSheetTheme: const BottomSheetThemeData(
        backgroundColor: AppColors.card,
        surfaceTintColor: Colors.transparent,
        dragHandleColor: Color(0xFFBDBDBD),
      ),
      listTileTheme: ListTileThemeData(
        tileColor: AppColors.card,
        selectedTileColor: scheme.primary.withValues(alpha: 0.08),
        textColor: scheme.onSurface,
        iconColor: scheme.onSurfaceVariant,
      ),
      dividerTheme: DividerThemeData(
        color: scheme.outline.withValues(alpha: 0.15),
      ),
    );
  }

  static InputDecorationTheme whiteInputDecorationTheme(ColorScheme scheme) {
    final textTheme = AppTypography.textTheme(scheme);

    return InputDecorationTheme(
      filled: true,
      fillColor: AppColors.card,
      border: OutlineInputBorder(borderRadius: BorderRadius.circular(8)),
      enabledBorder: OutlineInputBorder(
        borderRadius: BorderRadius.circular(8),
        borderSide: BorderSide(color: scheme.outline.withValues(alpha: 0.35)),
      ),
      focusedBorder: OutlineInputBorder(
        borderRadius: BorderRadius.circular(8),
        borderSide: BorderSide(color: scheme.primary, width: 2),
      ),
      disabledBorder: OutlineInputBorder(
        borderRadius: BorderRadius.circular(8),
        borderSide: BorderSide(color: scheme.outline.withValues(alpha: 0.2)),
      ),
      errorBorder: OutlineInputBorder(
        borderRadius: BorderRadius.circular(8),
        borderSide: BorderSide(color: scheme.error),
      ),
      focusedErrorBorder: OutlineInputBorder(
        borderRadius: BorderRadius.circular(8),
        borderSide: BorderSide(color: scheme.error, width: 2),
      ),
      contentPadding: const EdgeInsets.symmetric(horizontal: 16, vertical: 14),
      labelStyle: textTheme.bodyMedium,
      hintStyle: textTheme.bodyMedium?.copyWith(color: scheme.onSurfaceVariant),
      helperStyle: textTheme.bodySmall,
      errorStyle: textTheme.bodySmall?.copyWith(color: scheme.error),
    );
  }

  static ThemeData _buildTheme(ColorScheme colorScheme, Brightness brightness) {
    final isDark = brightness == Brightness.dark;
    final textTheme = AppTypography.textTheme(colorScheme);

    return ThemeData(
      useMaterial3: true,
      fontFamily: AppTypography.fontFamily,
      colorScheme: colorScheme,
      brightness: brightness,
      textTheme: textTheme,
      primaryTextTheme: textTheme,
      scaffoldBackgroundColor:
          isDark ? AppColors.darkBackground : AppColors.lightBackground,
      appBarTheme: AppBarTheme(
        centerTitle: false,
        elevation: 0,
        scrolledUnderElevation: 1,
        backgroundColor: isDark ? AppColors.darkSurface : AppColors.lightSurface,
        foregroundColor: isDark ? AppColors.textOnDark : AppColors.textPrimary,
        titleTextStyle: textTheme.titleLarge,
        toolbarTextStyle: textTheme.bodyLarge,
      ),
      cardTheme: CardThemeData(
        color: isDark ? AppColors.darkSurface : AppColors.lightSurface,
        surfaceTintColor: Colors.transparent,
        elevation: isDark ? 2 : 1,
        shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(12)),
        clipBehavior: Clip.antiAlias,
      ),
      inputDecorationTheme: InputDecorationTheme(
        filled: true,
        fillColor: isDark
            ? colorScheme.surfaceContainerHighest
            : colorScheme.surfaceContainerHighest.withValues(alpha: 0.5),
        border: OutlineInputBorder(borderRadius: BorderRadius.circular(8)),
        enabledBorder: OutlineInputBorder(
          borderRadius: BorderRadius.circular(8),
          borderSide: BorderSide(color: colorScheme.outline.withValues(alpha: 0.5)),
        ),
        focusedBorder: OutlineInputBorder(
          borderRadius: BorderRadius.circular(8),
          borderSide: BorderSide(color: colorScheme.primary, width: 2),
        ),
        contentPadding: const EdgeInsets.symmetric(horizontal: 16, vertical: 14),
        labelStyle: textTheme.bodyMedium,
        hintStyle: textTheme.bodyMedium?.copyWith(color: colorScheme.onSurfaceVariant),
        helperStyle: textTheme.bodySmall,
        errorStyle: textTheme.bodySmall?.copyWith(color: colorScheme.error),
      ),
      elevatedButtonTheme: ElevatedButtonThemeData(
        style: ElevatedButton.styleFrom(
          minimumSize: const Size(0, 48),
          shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(8)),
          padding: const EdgeInsets.symmetric(horizontal: 24, vertical: 12),
          textStyle: textTheme.labelLarge,
        ),
      ),
      outlinedButtonTheme: OutlinedButtonThemeData(
        style: OutlinedButton.styleFrom(
          minimumSize: const Size(0, 48),
          shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(8)),
          textStyle: textTheme.labelLarge,
        ),
      ),
      textButtonTheme: TextButtonThemeData(
        style: TextButton.styleFrom(
          minimumSize: const Size(0, 48),
          shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(8)),
          textStyle: textTheme.labelLarge,
        ),
      ),
      navigationRailTheme: NavigationRailThemeData(
        backgroundColor: isDark ? AppColors.darkSurface : AppColors.lightSurface,
        selectedIconTheme: IconThemeData(color: colorScheme.primary),
        selectedLabelTextStyle: textTheme.labelMedium?.copyWith(color: colorScheme.primary),
        unselectedLabelTextStyle: textTheme.labelMedium,
      ),
      drawerTheme: DrawerThemeData(
        backgroundColor: isDark ? AppColors.darkSurface : AppColors.lightSurface,
      ),
      dividerTheme: DividerThemeData(
        color: colorScheme.outline.withValues(alpha: 0.2),
      ),
      snackBarTheme: SnackBarThemeData(
        behavior: SnackBarBehavior.floating,
        shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(8)),
        contentTextStyle: textTheme.bodyMedium?.copyWith(color: colorScheme.onInverseSurface),
      ),
      dataTableTheme: DataTableThemeData(
        headingRowColor: WidgetStateProperty.all(
          colorScheme.surfaceContainerHighest.withValues(alpha: 0.5),
        ),
        headingTextStyle: textTheme.labelLarge,
        dataTextStyle: textTheme.bodyMedium,
      ),
      chipTheme: ChipThemeData(
        labelStyle: textTheme.labelSmall,
      ),
      dialogTheme: DialogThemeData(
        titleTextStyle: textTheme.titleLarge,
        contentTextStyle: textTheme.bodyMedium,
      ),
      listTileTheme: ListTileThemeData(
        titleTextStyle: textTheme.bodyLarge,
        subtitleTextStyle: textTheme.bodySmall,
      ),
      bottomNavigationBarTheme: BottomNavigationBarThemeData(
        selectedLabelStyle: textTheme.labelSmall,
        unselectedLabelStyle: textTheme.labelSmall,
      ),
      tabBarTheme: TabBarThemeData(
        labelStyle: textTheme.labelLarge,
        unselectedLabelStyle: textTheme.labelMedium,
      ),
    );
  }
}