// lib/features/gamification/models/gamification_models.dart
// Data models matching TechDocs v2 DB schema for the Contributor Module.

// ---------------------------------------------------------------------------
// Tier enum — matches PRD v3 §4.4 thresholds (based on Lifetime EP)
// ---------------------------------------------------------------------------
enum ContributorTier { BRONZE, SILVER, GOLD, PLATINUM, DIAMOND }

/// Returns the correct tier for a given lifetime EP total.
ContributorTier tierFromEp(int lifetimeEp) {
  if (lifetimeEp >= 5000) return ContributorTier.DIAMOND;
  if (lifetimeEp >= 1500) return ContributorTier.PLATINUM;
  if (lifetimeEp >= 500) return ContributorTier.GOLD;
  if (lifetimeEp >= 100) return ContributorTier.SILVER;
  return ContributorTier.BRONZE;
}

/// Human-readable label for a tier.
String tierLabel(ContributorTier tier) {
  switch (tier) {
    case ContributorTier.BRONZE:
      return 'Bronze';
    case ContributorTier.SILVER:
      return 'Silver';
    case ContributorTier.GOLD:
      return 'Gold';
    case ContributorTier.PLATINUM:
      return 'Platinum';
    case ContributorTier.DIAMOND:
      return 'Diamond';
  }
}

/// EP threshold for next tier (used for progress bar). Returns null at max tier.
int? nextTierThreshold(ContributorTier tier) {
  switch (tier) {
    case ContributorTier.BRONZE:
      return 100;
    case ContributorTier.SILVER:
      return 500;
    case ContributorTier.GOLD:
      return 1500;
    case ContributorTier.PLATINUM:
      return 5000;
    case ContributorTier.DIAMOND:
      return null;
  }
}

/// Lower EP bound for current tier (used for progress bar calculation).
int tierStartEp(ContributorTier tier) {
  switch (tier) {
    case ContributorTier.BRONZE:
      return 0;
    case ContributorTier.SILVER:
      return 100;
    case ContributorTier.GOLD:
      return 500;
    case ContributorTier.PLATINUM:
      return 1500;
    case ContributorTier.DIAMOND:
      return 5000;
  }
}

// ---------------------------------------------------------------------------
// UserGamificationProfile — mirrors the `UserGamificationProfile` DB table
// ---------------------------------------------------------------------------
class UserGamificationProfile {
  final String userId;
  final int lifetimeEp;  // Never resets. Used for tiers + leaderboard.
  final int currentEp;   // Liquid EP accumulated this month.
  final int currentRp;   // Spendable Reward Points.
  final ContributorTier tier;

  const UserGamificationProfile({
    required this.userId,
    required this.lifetimeEp,
    required this.currentEp,
    required this.currentRp,
    required this.tier,
  });

  factory UserGamificationProfile.fromJson(Map<String, dynamic> json) {
    final ep = (json['lifetime_ep'] as int?) ?? 0;
    return UserGamificationProfile(
      userId: json['user_id'] as String? ?? '',
      lifetimeEp: ep,
      currentEp: (json['current_ep'] as int?) ?? 0,
      currentRp: (json['current_rp'] as int?) ?? 0,
      tier: tierFromEp(ep),
    );
  }
}

// ---------------------------------------------------------------------------
// LeaderboardEntry — maps from Node.js API response fields
// ---------------------------------------------------------------------------
class LeaderboardEntry {
  final int rank;
  final String username;
  final String? avatarUrl;
  final int lifetimeEp;
  final int monthlyPoints;
  final ContributorTier tier;
  final int eventsCount;
  final bool isCurrentUser;
  final String? district;

  const LeaderboardEntry({
    required this.rank,
    required this.username,
    this.avatarUrl,
    required this.lifetimeEp,
    this.monthlyPoints = 0,
    required this.tier,
    required this.eventsCount,
    this.isCurrentUser = false,
    this.district,
  });

  factory LeaderboardEntry.fromJson(Map<String, dynamic> json) {
    // Node.js API returns 'points' for lifetime EP and 'name' for username
    final ep = (json['points'] as num?)?.toInt() ?? (json['lifetime_ep'] as num?)?.toInt() ?? 0;
    final tierStr = json['level'] as String? ?? json['tier'] as String?;
    return LeaderboardEntry(
      rank: (json['rank'] as num?)?.toInt() ?? 0,
      username: json['name'] as String? ?? json['username'] as String? ?? '',
      avatarUrl: json['avatar_url'] as String?,
      lifetimeEp: ep,
      monthlyPoints: (json['monthlyPoints'] as num?)?.toInt() ?? 0,
      tier: tierStr != null ? _tierFromString(tierStr) : tierFromEp(ep),
      eventsCount: (json['eventsAdded'] as num?)?.toInt() ?? (json['events_count'] as num?)?.toInt() ?? 0,
      isCurrentUser: (json['is_current_user'] as bool?) ?? false,
      district: json['district'] as String?,
    );
  }
}

/// Parse tier string from API (e.g. "Gold") to enum.
ContributorTier _tierFromString(String s) {
  switch (s.toLowerCase()) {
    case 'diamond':  return ContributorTier.DIAMOND;
    case 'platinum': return ContributorTier.PLATINUM;
    case 'gold':     return ContributorTier.GOLD;
    case 'silver':   return ContributorTier.SILVER;
    default:         return ContributorTier.BRONZE;
  }
}

// ---------------------------------------------------------------------------
// CurrentUserStats — from leaderboard API's currentUser field
// ---------------------------------------------------------------------------
class CurrentUserStats {
  final int rank;
  final int points;
  final int monthlyPoints;
  final String level;
  final int rewardCycleDays;
  final int eventsAdded;
  final String? district;

  const CurrentUserStats({
    required this.rank,
    required this.points,
    this.monthlyPoints = 0,
    required this.level,
    this.rewardCycleDays = 0,
    this.eventsAdded = 0,
    this.district,
  });

  factory CurrentUserStats.fromJson(Map<String, dynamic> json) {
    return CurrentUserStats(
      rank: (json['rank'] as num?)?.toInt() ?? 0,
      points: (json['points'] as num?)?.toInt() ?? 0,
      monthlyPoints: (json['monthlyPoints'] as num?)?.toInt() ?? 0,
      level: json['level'] as String? ?? 'Bronze',
      rewardCycleDays: (json['rewardCycleDays'] as num?)?.toInt() ?? 0,
      eventsAdded: (json['eventsAdded'] as num?)?.toInt() ?? 0,
      district: json['district'] as String?,
    );
  }
}

// ---------------------------------------------------------------------------
// LeaderboardResponse — wraps the full leaderboard API response
// ---------------------------------------------------------------------------
class LeaderboardResponse {
  final List<LeaderboardEntry> entries;
  final CurrentUserStats? currentUser;
  final int totalParticipants;

  const LeaderboardResponse({
    required this.entries,
    this.currentUser,
    this.totalParticipants = 0,
  });
}

// ---------------------------------------------------------------------------
// SubmissionModel — event submissions from dashboard API
// ---------------------------------------------------------------------------
class SubmissionModel {
  final String id;
  final String eventName;
  final String category;
  final String status; // PENDING, APPROVED, REJECTED
  final String? district;
  final int epAwarded;
  final DateTime createdAt;
  final List<String> images;

  const SubmissionModel({
    required this.id,
    required this.eventName,
    this.category = '',
    required this.status,
    this.district,
    this.epAwarded = 0,
    required this.createdAt,
    this.images = const [],
  });

  factory SubmissionModel.fromJson(Map<String, dynamic> json) {
    final rawImages = json['images'] as List? ?? [];
    return SubmissionModel(
      id: (json['id'] ?? json['submission_id'] ?? '').toString(),
      eventName: json['event_name'] as String? ?? '',
      category: json['category'] as String? ?? '',
      status: json['status'] as String? ?? 'PENDING',
      district: json['district'] as String?,
      epAwarded: (json['total_ep_awarded'] as num?)?.toInt() ?? (json['ep_awarded'] as num?)?.toInt() ?? 0,
      createdAt: DateTime.tryParse(json['created_at'] as String? ?? '') ?? DateTime.now(),
      images: rawImages.map((e) => e.toString()).toList(),
    );
  }
}

// ---------------------------------------------------------------------------
// DashboardResponse — wraps the full dashboard API response
// ---------------------------------------------------------------------------
class DashboardResponse {
  final UserGamificationProfile profile;
  final List<SubmissionModel> submissions;

  const DashboardResponse({
    required this.profile,
    this.submissions = const [],
  });
}

// ---------------------------------------------------------------------------
// ShopItem — mirrors `RedeemShopItem` table
// ---------------------------------------------------------------------------
class ShopItem {
  final String id;
  final String name;
  final String description;
  final int rpCost;
  final int stockQuantity;
  final String? imageUrl;

  const ShopItem({
    required this.id,
    required this.name,
    required this.description,
    required this.rpCost,
    required this.stockQuantity,
    this.imageUrl,
  });

  factory ShopItem.fromJson(Map<String, dynamic> json) {
    return ShopItem(
      id: json['id'] as String? ?? '',
      name: json['name'] as String? ?? '',
      description: json['description'] as String? ?? '',
      rpCost: (json['rp_cost'] as int?) ?? 0,
      stockQuantity: (json['stock_quantity'] as int?) ?? 0,
      imageUrl: json['image_url'] as String?,
    );
  }
}

// ---------------------------------------------------------------------------
// RedemptionRecord — mirrors `RedemptionHistory` table
// ---------------------------------------------------------------------------
class RedemptionRecord {
  final String id;
  final String itemId;
  final int rpSpent;
  final String voucherCode;
  final DateTime timestamp;

  const RedemptionRecord({
    required this.id,
    required this.itemId,
    required this.rpSpent,
    required this.voucherCode,
    required this.timestamp,
  });

  factory RedemptionRecord.fromJson(Map<String, dynamic> json) {
    return RedemptionRecord(
      id: json['id'] as String? ?? '',
      itemId: json['item_id'] as String? ?? '',
      rpSpent: (json['rp_spent'] as int?) ?? 0,
      voucherCode: json['voucher_code_issued'] as String? ?? '',
      timestamp: DateTime.tryParse(json['timestamp'] as String? ?? '') ?? DateTime.now(),
    );
  }
}

// ---------------------------------------------------------------------------
// AchievementBadge
// ---------------------------------------------------------------------------
class AchievementBadge {
  final String id;
  final String title;
  final String description;
  final String iconName; // maps to an IconData key
  final bool isUnlocked;
  final double progress; // 0.0 – 1.0

  const AchievementBadge({
    required this.id,
    required this.title,
    required this.description,
    required this.iconName,
    required this.isUnlocked,
    required this.progress,
  });
}