import 'package:flutter/foundation.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';
import '../models/sake_item.dart';
import '../models/schema/sake_taste_stats.dart';

final shukoDiagnosisServiceProvider = Provider((ref) => ShukoDiagnosisService());

class ShukoDiagnosisService {
  ShukoProfile diagnose(List<SakeItem> items) {
    if (items.isEmpty) {
      return ShukoProfile.empty();
    }

    // 1. Calculate Average Stats (only from items with valid data)
    double totalAroma = 0;
    double totalBitterness = 0;
    double totalSweetness = 0;
    double totalAcidity = 0;
    double totalBody = 0;
    int count = 0;

    debugPrint('🍶🍶🍶 SHUKO DIAGNOSIS START: Total items = ${items.length}');

    for (var item in items) {
      final stats = item.hiddenSpecs.sakeTasteStats;

      // Skip items with empty tasteStats (all zeros)
      if (stats.aroma == 0 && stats.bitterness == 0 && stats.sweetness == 0 &&
          stats.acidity == 0 && stats.body == 0) {
        debugPrint('🍶 SKIPPED item (all zeros)');
        continue;
      }

      totalAroma += stats.aroma;
      totalBitterness += stats.bitterness;
      totalSweetness += stats.sweetness;
      totalAcidity += stats.acidity;
      totalBody += stats.body;
      count++;
    }

    debugPrint('🍶🍶🍶 Analyzed $count out of ${items.length} items');

    if (count == 0) {
      debugPrint('🍶🍶🍶 WARNING: No items to analyze, returning empty profile');
      return ShukoProfile.empty();
    }

    final avgStats = SakeTasteStats(
      aroma: totalAroma / count,
      bitterness: totalBitterness / count,
      sweetness: totalSweetness / count,
      acidity: totalAcidity / count,
      body: totalBody / count,
    );

    // 2. Determine Title based on dominant traits
    final title = _determineTitle(avgStats);

    return ShukoProfile(
      title: title.title,
      description: title.description,
      avgStats: avgStats,
      totalSakeCount: items.length,
      analyzedCount: count,
    );
  }

  ShukoTitle _determineTitle(SakeTasteStats stats) {
    // DEBUG: Print average stats
    debugPrint('🔍 DEBUG avgStats: aroma=${stats.aroma.toStringAsFixed(2)}, bitterness=${stats.bitterness.toStringAsFixed(2)}, sweetness=${stats.sweetness.toStringAsFixed(2)}, acidity=${stats.acidity.toStringAsFixed(2)}, body=${stats.body.toStringAsFixed(2)}');

    // Scoring-based logic to handle overlapping traits
    final Map<String, double> scores = {};

    // 1. 辛口サムライ (Dry Samurai)
    // High Bitterness (Sharpness) + Low Sweetness
    // Old: alcoholFeeling + Low sweetness
    scores['辛口サムライ'] = _calculateDryScore(stats);

    // 2. フルーティーマスター (Fruity Master)
    // High Aroma + High Sweetness (Modern Fruity Ginjo Style)
    // Old: fruitiness + High sweetness
    scores['フルーティーマスター'] = _calculateFruityScore(stats);

    // 3. 旨口探求者 (Umami Explorer)
    // High Body (Richness)
    // Old: richness
    scores['旨口探求者'] = _calculateRichnessScore(stats);

    // 4. 香りの貴族 (Aroma Noble)
    // High Aroma (dominant trait)
    scores['香りの貴族'] = _calculateAromaScore(stats);

    // 5. バランスの賢者 (Balance Sage)
    // All stats moderate and balanced
    scores['バランスの賢者'] = _calculateBalanceScore(stats);

    // DEBUG: Print all scores
    debugPrint('🔍 DEBUG scores: ${scores.entries.map((e) => '${e.key}=${e.value.toStringAsFixed(2)}').join(', ')}');

    // Find the title with the highest score
    final maxEntry = scores.entries.reduce((a, b) => a.value > b.value ? a : b);

    debugPrint('🔍 DEBUG winner: ${maxEntry.key} with score ${maxEntry.value.toStringAsFixed(2)}');

    // Threshold: require minimum score to avoid false positives
    // Lowered to 1.5 to be more forgiving for "Standard" sake
    if (maxEntry.value < 1.0) {
      debugPrint('🔍 DEBUG: Score too low (${maxEntry.value.toStringAsFixed(2)} < 1.0), returning default title');
      // Proposed New Default Titles
      return const ShukoTitle(
        title: '酒道の旅人',
        description: '未知なる味を求めて各地を巡る、終わりのない旅の途中。',
      );
    }

    // Return the winning title
    return _getTitleByName(maxEntry.key);
  }

  // Scoring functions for each type
  double _calculateDryScore(SakeTasteStats stats) {
    double score = 0;
    // Dry = Sharp/Bitter + Not Sweet
    if (stats.bitterness > 0.1) {
      if (stats.bitterness > 3.0) score += (stats.bitterness - 3.0) * 2; // Lowered from 3.2
      
      // Also verify Acidity contributions (Acid + Bitter = Dry)
      if (stats.acidity > 3.0) score += (stats.acidity - 3.0);

      // Penalize if too sweet
      if (stats.sweetness < 2.5) {
         score += (2.5 - stats.sweetness) * 2;
      } else if (stats.sweetness > 3.5) {
         score -= (stats.sweetness - 3.5) * 2;
      }
    }
    return score;
  }

  double _calculateFruityScore(SakeTasteStats stats) {
    double score = 0;
    // Fruity = High Aroma + Moderate/High Sweetness
    if (stats.aroma > 0.1) {
      if (stats.aroma > 2.8) score += (stats.aroma - 2.8) * 1.5; // Lowered from 3.0
      
      // Verify Sweetness support
      if (stats.sweetness > 2.8) score += (stats.sweetness - 2.8) * 1.5;

      // Bonus if Body is not too heavy (Light + Sweet + Aroma = Fruity)
      if (stats.body < 3.5) score += 0.5;
    }
    return score;
  }

  double _calculateRichnessScore(SakeTasteStats stats) {
    double score = 0;
    // Richness = High Body (Kokumi) + Sweetness or Bitterness
    if (stats.body > 0.1) {
      // Body is the primary driver
      if (stats.body > 3.0) score += (stats.body - 3.0) * 2.5; // Lowered from 3.3
      
      // Bonus for complexity
      if (stats.bitterness > 3.0) score += 0.5;
    }
    return score;
  }

  double _calculateAromaScore(SakeTasteStats stats) {
    double score = 0;
    // Pure Aroma focus (Daiginjo style)
    // Lowered threshold significantly to capture "Aroma Type" even if not extreme
    if (stats.aroma > 3.0) {
      score += (stats.aroma - 3.0) * 3; 
    }
    // Boost score if it is the dominant trait
    if (stats.aroma > stats.body && stats.aroma > stats.bitterness) {
       score += 1.0;
    }
    return score;
  }

  double _calculateBalanceScore(SakeTasteStats stats) {
    double score = 0;
    
    // Check range (Max - Min)
    final values = [stats.aroma, stats.sweetness, stats.acidity, stats.bitterness, stats.body];
    final maxVal = values.reduce((a, b) => a > b ? a : b);
    final minVal = values.reduce((a, b) => a < b ? a : b);
    final spread = maxVal - minVal;

    // Strict requirement for "Balance":
    // The difference between the highest and lowest trait must be small.
    if (spread > 1.5) {
      return 0; // Not balanced if there's a spike
    }

    int validStats = 0;
    double sumDiffFrom3 = 0;

    // Check deviation from 3.0 (Center)
    void checkStat(double val) {
      if (val > 0.1) {
        validStats++;
        sumDiffFrom3 += (val - 3.0).abs();
      }
    }

    checkStat(stats.aroma);
    checkStat(stats.sweetness);
    checkStat(stats.acidity);
    checkStat(stats.bitterness);
    checkStat(stats.body);

    if (validStats >= 3) {
      double avgDev = sumDiffFrom3 / validStats;
      // If average deviation is small (< 0.7), it's balanced
      if (avgDev < 0.7) {
        score = (0.8 - avgDev) * 5; // Higher score for tighter balance
      }
    }

    return score;
  }

  ShukoTitle _getTitleByName(String name) {
    switch (name) {
      case '辛口サムライ':
        return const ShukoTitle(
          title: '辛口サムライ',
          description: 'キレのある辛口を好む、硬派な日本酒ファン。', // Updated Description?
        );
      case 'フルーティーマスター':
        return const ShukoTitle(
          title: 'フルーティーマスター',
          description: '果実のような香りと甘みを愛する、華やかな飲み手。',
        );
      case '旨口探求者':
        return const ShukoTitle(
          title: '旨口探求者',
          description: 'お米本来の旨みやコクを重視する、通な舌の持ち主。',
        );
      case '香りの貴族':
        return const ShukoTitle(
          title: '香りの貴族',
          description: '吟醸香など、鼻に抜ける香りを何より楽しむタイプ。',
        );
      case 'バランスの賢者':
        return const ShukoTitle(
          title: 'バランスの賢者',
          description: '偏りなく様々な酒を楽しむ、オールラウンダー。',
        );
      default:
        // New Default Title
        return const ShukoTitle(
          title: '酒道の旅人',
          description: '未知なる味を求めて各地を巡る、終わりのない旅の途中。',
        );
    }
  }

  // v1.1: Personalization Logic
  String getGreeting(String? nickname) {
    if (nickname == null || nickname.trim().isEmpty) {
      return 'ようこそ！';
    }
    return 'ようこそ、$nicknameさん';
  }

  ShukoTitle personalizeTitle(ShukoTitle original, String? gender) {
    if (gender == null) return original;

    String newTitle = original.title;

    // Simple customization logic
    if (gender == 'female') {
      if (newTitle.contains('サムライ')) newTitle = newTitle.replaceAll('サムライ', '麗人');
      if (newTitle.contains('貴族')) newTitle = newTitle.replaceAll('貴族', 'プリンセス');
      if (newTitle.contains('賢者')) newTitle = newTitle.replaceAll('賢者', 'ミューズ');
      if (newTitle.contains('愛好家')) newTitle = newTitle.replaceAll('愛好家', '目利き'); // Feminine variant
    } else if (gender == 'male') {
       if (newTitle.contains('貴族')) newTitle = newTitle.replaceAll('貴族', '貴公子');
    }

    return ShukoTitle(
      title: newTitle,
      description: original.description,
    );
  }
}

class ShukoProfile {
  final String title;
  final String description;
  final SakeTasteStats avgStats;
  final int totalSakeCount;
  final int analyzedCount;

  ShukoProfile({
    required this.title,
    required this.description,
    required this.avgStats,
    required this.totalSakeCount,
    required this.analyzedCount,
  });

  factory ShukoProfile.empty() {
    return ShukoProfile(
      title: '旅の始まり',
      description: 'まずは日本酒を記録して、\n自分の好みを発見しましょう。',
      avgStats: SakeTasteStats(aroma: 0, bitterness: 0, sweetness: 0, acidity: 0, body: 0),
      totalSakeCount: 0,
      analyzedCount: 0,
    );
  }
}

class ShukoTitle {
  final String title;
  final String description;
  const ShukoTitle({required this.title, required this.description});
}