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

enum AppThemeType {
  basic,
  pop,
}

class AppTheme {
  // ============================================================================
  // BASIC THEME PALETTE (Current/Original Theme)
  // ============================================================================
  
  // ANCHORS (The 60%)
  static const Color basicNavyBlue = Color(0xFF000383);
  static const Color basicNavyText = Color(0xFF000383);
  
  // FLOW & STRUCTURE (The 30%)
  static const Color basicEgyptianBlue = Color(0xFF0E38AE);
  static const Color basicBrightNavy = Color(0xFF1974D1);
  
  // ACCENTS (The 10%)
  static const Color basicRoyalPurple = Color(0xFF7751A8);
  static const Color basicKsuPurple = Color(0xFF512889);
  
  // NEUTRALS & BACKGROUNDS
  static const Color basicQueenPink = Color(0xFFE5C0DD);
  static const Color basicQueenPinkLight = Color(0xFFF9F2F7);
  static const Color basicWhite = Color(0xFFFFFFFF);

  // ============================================================================
  // POP THEME PALETTE - "Awakening" - High Contrast & Energy
  // ============================================================================

  // 60% - The Anchors (Deep & Grounded)
  static const Color popNavyBlue = Color(0xFF000383);
  static const Color popNavyText = Color(0xFF0D1050);

  // 30% - Structure & Flow (Bright & Defined)
  static const Color popEgyptianBlue = Color(0xFF0E38AE);
  static const Color popBrightNavy = Color(0xFF1974D1);

  // 10% - The Pop (Vibrant Accents)
  static const Color popRoyalPurple = Color(0xFF7751A8);
  static const Color popKsuPurple = Color(0xFF512889);

  // Backgrounds - The "Clean" Space
  static const Color popScaffoldBg = Color(0xFFF9F6F9);
  static const Color popCardSurface = Colors.white;
  
  // Interaction
  static const Color popHighlight = Color(0xFFE5C0DD);

  // ============================================================================
  // CURRENT THEME COLORS (Dynamic based on selected theme)
  // ============================================================================

  static AppThemeType _currentThemeType = AppThemeType.basic;

  static void setThemeType(AppThemeType type) {
    _currentThemeType = type;
  }

  static bool get isPop => _currentThemeType == AppThemeType.pop;

  // Dynamic color getters
  static Color get navyBlue => isPop ? popNavyBlue : basicNavyBlue;
  static Color get navyText => isPop ? popNavyText : basicNavyText;
  static Color get egyptianBlue => isPop ? popEgyptianBlue : basicEgyptianBlue;
  static Color get brightNavy => isPop ? popBrightNavy : basicBrightNavy;
  static Color get royalPurple => isPop ? popRoyalPurple : basicRoyalPurple;
  static Color get ksuPurple => isPop ? popKsuPurple : basicKsuPurple;
  static Color get queenPink => isPop ? popHighlight : basicQueenPink;
  static Color get queenPinkLight => scaffoldBg; // Alias for backward compatibility
  static Color get scaffoldBg => isPop ? popScaffoldBg : basicQueenPinkLight;
  static Color get cardSurface => isPop ? popCardSurface : basicWhite;
  static const Color white = basicWhite;

  // SEMANTIC
  static const Color error = Color(0xFFD32F2F);
  static const Color success = basicKsuPurple;
  static const Color warning = Color(0xFFFBC02D);
  static const Color info = Color(0xFF2196F3);

  // Trust Tiers
  static Color get tierEstablished => egyptianBlue;
  static Color get tierTrusted => royalPurple;
  static const Color tierNew = Colors.grey;

  // ============================================================================
  // DIMENSIONS
  // ============================================================================

  static const double spacingSm = 12.0;
  static const double spacingMd = 16.0;
  static const double spacingLg = 24.0;
  static const double spacingXs = 4.0;
  static const double spacing2xs = 2.0;

  // Radii
  static const double radiusSm = 4.0;
  static const double radiusXs = 2.0;
  static const double radiusMd = 8.0;
  static const double radiusMdValue = 8.0;
  static const double radiusFull = 36.0;

  // Text Colors - COLOR HIERARCHY: Content neutral, UI branded
  static Color get textPrimary => navyText;      // Names, handles, UI
  static Color get textSecondary => navyText;    // Names, handles, UI
  static Color get textTertiary => navyText;     // Names, handles, UI
  static const Color textDisabled = Colors.grey;
  static const Color textOnAccent = white;
  static Color get border => egyptianBlue;
  
  // Post Content - Neutral for contrast with purple UI
  static const Color postContent = Color(0xFF1A1A1A);
  static const Color postContentLight = Color(0xFF4A4A4A);

  // STRICT SEPARATION
  static const double borderWidth = 1.5;
  static const double dividerThickness = 2.0;
  static const double flowLineWidth = 3.0;

  // Post Specific Spacing
  static const double spacingPostShort = 16.0;
  static const double spacingPostMedium = 24.0;
  static const double spacingPostLong = 32.0;

  // ============================================================================
  // TYPOGRAPHY (Literata + Navy Blue) - STRICT FLAT DESIGN
  // ============================================================================

  static TextTheme get textTheme => GoogleFonts.literataTextTheme().copyWith(
    // Hero Body Text - Main post content (NEUTRAL for contrast with purple UI)
    bodyLarge: GoogleFonts.literata(
      fontSize: 17,
      height: 1.5,
      fontWeight: FontWeight.w400,
      color: postContent,
    ),
    // Standard Body - Secondary content (NEUTRAL)
    bodyMedium: GoogleFonts.literata(
      fontSize: 16,
      height: 1.5,
      fontWeight: FontWeight.w400,
      color: postContentLight,
    ),
    // Metadata / UI Elements (Sans-serif)
    labelSmall: GoogleFonts.inter(
      fontSize: 13,
      fontWeight: FontWeight.w600,
      color: egyptianBlue,
      letterSpacing: 0.2,
    ),
    labelMedium: GoogleFonts.inter(
      fontSize: 14,
      fontWeight: FontWeight.w600,
      color: brightNavy,
      letterSpacing: 0,
    ),
    // Author Name - Visual anchor, ExtraBold Navy Blue
    labelLarge: GoogleFonts.inter(
      fontSize: 15,
      fontWeight: FontWeight.w800,
      color: navyBlue,
    ),
    // Headlines
    headlineSmall: GoogleFonts.literata(
      fontSize: 22,
      fontWeight: FontWeight.w700,
      color: navyBlue,
      letterSpacing: -0.5,
    ),
    headlineMedium: GoogleFonts.literata(
      fontSize: 26,
      fontWeight: FontWeight.w700,
      color: navyBlue,
      letterSpacing: 0,
    ),
  );

  // Backward Compat Getters
  static TextStyle get postBody => textTheme.bodyLarge!;
  static TextStyle get postBodyShort => textTheme.bodyLarge!.copyWith(fontSize: 22);
  static TextStyle get postBodyLong => textTheme.bodyLarge!.copyWith(fontSize: 18);
  static TextStyle get postBodyReflective => textTheme.bodyLarge!.copyWith(
    fontStyle: FontStyle.italic, 
    color: ksuPurple
  );

  // Text Style Getters
  static TextStyle get bodyMedium => textTheme.bodyMedium!;
  static TextStyle get bodyLarge => textTheme.bodyLarge!;
  static TextStyle get headlineMedium => textTheme.headlineMedium!;
  static TextStyle get headlineSmall => textTheme.headlineSmall!;
  static TextStyle get labelMedium => textTheme.labelMedium!;
  static TextStyle get labelSmall => textTheme.labelSmall!;

  // ============================================================================
  // THEME DATA
  // ============================================================================

  static ThemeData get lightTheme {
    return ThemeData(
      useMaterial3: true,
      brightness: Brightness.light,
      scaffoldBackgroundColor: scaffoldBg,
      primaryColor: navyBlue,
      
      // Color Scheme
      colorScheme: ColorScheme.light(
        primary: navyBlue,
        secondary: brightNavy,
        tertiary: royalPurple,
        surface: cardSurface,
        onSurface: navyText,
        error: error,
      ),

      // Text Theme
      textTheme: textTheme,
      fontFamily: GoogleFonts.literata().fontFamily,

      // AppBar (High Contrast)
      appBarTheme: AppBarTheme(
        backgroundColor: cardSurface,
        surfaceTintColor: Colors.transparent,
        elevation: 0,
        centerTitle: false,
        iconTheme: IconThemeData(color: navyBlue),
        titleTextStyle: textTheme.headlineSmall,
        systemOverlayStyle: SystemUiOverlayStyle.dark,
        shape: Border(
          bottom: BorderSide(color: egyptianBlue, width: isPop ? 2 : borderWidth),
        ),
      ),

      // Card Theme (Defined Edges)
      cardTheme: CardThemeData(
        color: cardSurface,
        elevation: 0,
        margin: EdgeInsets.zero,
        shape: RoundedRectangleBorder(
          borderRadius: BorderRadius.circular(12),
          side: BorderSide(color: egyptianBlue, width: 1),
        ),
      ),

      // Buttons
      elevatedButtonTheme: ElevatedButtonThemeData(
        style: ElevatedButton.styleFrom(
          backgroundColor: brightNavy,
          foregroundColor: white,
          elevation: 0,
          padding: const EdgeInsets.symmetric(horizontal: 24, vertical: 16),
          shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(8)),
          textStyle: GoogleFonts.inter(fontWeight: FontWeight.bold),
        ),
      ),

      textButtonTheme: TextButtonThemeData(
        style: TextButton.styleFrom(
          foregroundColor: egyptianBlue,
          textStyle: GoogleFonts.inter(fontWeight: FontWeight.w600),
        ),
      ),

      // Bottom Nav
      bottomNavigationBarTheme: BottomNavigationBarThemeData(
        backgroundColor: cardSurface,
        selectedItemColor: royalPurple,
        unselectedItemColor: const Color(0xFF9EA3B0),
        type: BottomNavigationBarType.fixed,
        showSelectedLabels: !isPop,
        showUnselectedLabels: !isPop,
        elevation: isPop ? 10 : 0,
      ),

      // Floating Action Button
      floatingActionButtonTheme: FloatingActionButtonThemeData(
        backgroundColor: brightNavy,
        foregroundColor: Colors.white,
        elevation: isPop ? 4 : 6,
        shape: isPop ? const CircleBorder() : null,
      ),

      // Divider (Hard & Visible)
      dividerTheme: DividerThemeData(
        color: queenPink,
        thickness: 1,
        space: 24, 
      ),
      
      // Input Fields
      inputDecorationTheme: InputDecorationTheme(
        filled: true,
        fillColor: cardSurface,
        contentPadding: const EdgeInsets.all(16),
        border: OutlineInputBorder(
          borderRadius: BorderRadius.circular(8),
          borderSide: BorderSide(color: egyptianBlue, width: 1),
        ),
        enabledBorder: OutlineInputBorder(
          borderRadius: BorderRadius.circular(8),
          borderSide: BorderSide(color: egyptianBlue, width: 1),
        ),
        focusedBorder: OutlineInputBorder(
          borderRadius: BorderRadius.circular(8),
          borderSide: BorderSide(color: royalPurple, width: 2),
        ),
      ),
    );
  }
}