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

ThemeData appTheme() {
  final base = ColorScheme.fromSeed(
    seedColor: AppColors.primary,
    brightness: Brightness.light,
    surface: AppColors.surface,
    onSurface: AppColors.textPrimary,
  ).copyWith(
    primary: AppColors.primary,
    onPrimary: Colors.white,
    secondary: AppColors.primary,
    onSecondary: Colors.white,
    tertiary: AppColors.primary,
    error: AppColors.error,
    surfaceContainerHighest: AppColors.surfaceTertiary,
    onSurfaceVariant: AppColors.textSecondary,
    outline: AppColors.separator,
  );

  return ThemeData(
    useMaterial3: true,
    colorScheme: base,
    fontFamily: GoogleFonts.roboto().fontFamily,
    scaffoldBackgroundColor: AppColors.background,

    // ── AppBar ────────────────────────────────────────
    appBarTheme: const AppBarTheme(
      centerTitle: true,
      elevation: 0,
      scrolledUnderElevation: 0,
      backgroundColor: AppColors.background,
      foregroundColor: AppColors.textPrimary,
      systemOverlayStyle: SystemUiOverlayStyle(
        statusBarBrightness: Brightness.light,
        statusBarIconBrightness: Brightness.dark,
      ),
      titleTextStyle: TextStyle(
        color: AppColors.textPrimary,
        fontSize: 17,
        fontWeight: FontWeight.w600,
        letterSpacing: -0.4,
      ),
    ),

    // ── Card ──────────────────────────────────────────
    // iOS: white cards on grey background, no shadow
    cardTheme: CardThemeData(
      elevation: 0,
      color: AppColors.surface,
      surfaceTintColor: Colors.transparent,
      shape: RoundedRectangleBorder(
        borderRadius: BorderRadius.circular(12),
      ),
    ),

    // ── Bottom navigation ─────────────────────────────
    bottomNavigationBarTheme: const BottomNavigationBarThemeData(
      backgroundColor: AppColors.surface,
      selectedItemColor: AppColors.primary,
      unselectedItemColor: AppColors.textSecondary,
      type: BottomNavigationBarType.fixed,
      elevation: 0,
      selectedLabelStyle: TextStyle(
        fontSize: 10,
        fontWeight: FontWeight.w500,
        letterSpacing: -0.2,
      ),
      unselectedLabelStyle: TextStyle(fontSize: 10),
    ),

    // ── Buttons ───────────────────────────────────────
    filledButtonTheme: FilledButtonThemeData(
      style: FilledButton.styleFrom(
        minimumSize: const Size(double.infinity, 50),
        backgroundColor: AppColors.primary,
        foregroundColor: Colors.white,
        elevation: 0,
        shape: RoundedRectangleBorder(
          borderRadius: BorderRadius.circular(12),
        ),
        textStyle: const TextStyle(
          fontSize: 17,
          fontWeight: FontWeight.w600,
          letterSpacing: -0.3,
        ),
      ),
    ),
    elevatedButtonTheme: ElevatedButtonThemeData(
      style: ElevatedButton.styleFrom(
        minimumSize: const Size(double.infinity, 50),
        elevation: 0,
        shape: RoundedRectangleBorder(
          borderRadius: BorderRadius.circular(12),
        ),
      ),
    ),
    outlinedButtonTheme: OutlinedButtonThemeData(
      style: OutlinedButton.styleFrom(
        minimumSize: const Size(double.infinity, 50),
        side: const BorderSide(color: AppColors.primary),
        shape: RoundedRectangleBorder(
          borderRadius: BorderRadius.circular(12),
        ),
        textStyle: const TextStyle(
          fontSize: 17,
          fontWeight: FontWeight.w400,
          letterSpacing: -0.3,
        ),
      ),
    ),

    // ── Inputs ────────────────────────────────────────
    inputDecorationTheme: InputDecorationTheme(
      filled: true,
      fillColor: AppColors.surface,
      border: OutlineInputBorder(
        borderRadius: BorderRadius.circular(10),
        borderSide: const BorderSide(color: AppColors.separator),
      ),
      enabledBorder: OutlineInputBorder(
        borderRadius: BorderRadius.circular(10),
        borderSide: const BorderSide(color: AppColors.separator),
      ),
      focusedBorder: OutlineInputBorder(
        borderRadius: BorderRadius.circular(10),
        borderSide: const BorderSide(color: AppColors.primary, width: 1.5),
      ),
      errorBorder: OutlineInputBorder(
        borderRadius: BorderRadius.circular(10),
        borderSide: const BorderSide(color: AppColors.error),
      ),
      contentPadding: const EdgeInsets.symmetric(horizontal: 16, vertical: 14),
      hintStyle: const TextStyle(color: AppColors.textSecondary),
    ),

    // ── ListTile ──────────────────────────────────────
    listTileTheme: const ListTileThemeData(
      contentPadding: EdgeInsets.symmetric(horizontal: 16),
      minVerticalPadding: 12,
    ),

    // ── Divider ───────────────────────────────────────
    dividerTheme: const DividerThemeData(
      color: AppColors.separator,
      space: 1,
      thickness: 0.5,
      indent: 16,
    ),

    // ── Chip ──────────────────────────────────────────
    chipTheme: ChipThemeData(
      shape: RoundedRectangleBorder(
        borderRadius: BorderRadius.circular(20),
      ),
      side: const BorderSide(color: AppColors.separator),
    ),

    // ── Dialog ───────────────────────────────────────
    dialogTheme: DialogThemeData(
      backgroundColor: AppColors.surface,
      surfaceTintColor: Colors.transparent,
      elevation: 0,
      shape: RoundedRectangleBorder(
        borderRadius: BorderRadius.circular(14),
      ),
    ),

    // ── Bottom sheet ─────────────────────────────────
    bottomSheetTheme: const BottomSheetThemeData(
      backgroundColor: AppColors.surface,
      surfaceTintColor: Colors.transparent,
      elevation: 0,
      shape: RoundedRectangleBorder(
        borderRadius: BorderRadius.vertical(top: Radius.circular(12)),
      ),
    ),

    // ── Text ─────────────────────────────────────────
    textTheme: const TextTheme(
      headlineLarge: TextStyle(
        fontSize: 34,
        fontWeight: FontWeight.w700,
        letterSpacing: -0.5,
        color: AppColors.textPrimary,
      ),
      headlineMedium: TextStyle(
        fontSize: 28,
        fontWeight: FontWeight.w700,
        letterSpacing: -0.4,
        color: AppColors.textPrimary,
      ),
      headlineSmall: TextStyle(
        fontSize: 22,
        fontWeight: FontWeight.w700,
        letterSpacing: -0.3,
        color: AppColors.textPrimary,
      ),
      titleLarge: TextStyle(
        fontSize: 20,
        fontWeight: FontWeight.w600,
        letterSpacing: -0.3,
        color: AppColors.textPrimary,
      ),
      titleMedium: TextStyle(
        fontSize: 17,
        fontWeight: FontWeight.w600,
        letterSpacing: -0.3,
        color: AppColors.textPrimary,
      ),
      titleSmall: TextStyle(
        fontSize: 15,
        fontWeight: FontWeight.w600,
        letterSpacing: -0.2,
        color: AppColors.textPrimary,
      ),
      bodyLarge: TextStyle(
        fontSize: 17,
        fontWeight: FontWeight.w400,
        letterSpacing: -0.3,
        color: AppColors.textPrimary,
      ),
      bodyMedium: TextStyle(
        fontSize: 15,
        fontWeight: FontWeight.w400,
        letterSpacing: -0.2,
        color: AppColors.textPrimary,
      ),
      bodySmall: TextStyle(
        fontSize: 13,
        fontWeight: FontWeight.w400,
        letterSpacing: -0.1,
        color: AppColors.textSecondary,
      ),
      labelLarge: TextStyle(
        fontSize: 15,
        fontWeight: FontWeight.w500,
        letterSpacing: -0.2,
        color: AppColors.textPrimary,
      ),
      labelMedium: TextStyle(
        fontSize: 13,
        fontWeight: FontWeight.w500,
        letterSpacing: -0.1,
        color: AppColors.textPrimary,
      ),
      labelSmall: TextStyle(
        fontSize: 11,
        fontWeight: FontWeight.w400,
        letterSpacing: 0,
        color: AppColors.textSecondary,
      ),
    ),
  );
}