import Foundation
import SwiftUI

// MARK: - Challenge

struct Challenge: Identifiable, Equatable, Codable {
    let id: String
    let title: String
    let description: String
    let challengeType: ChallengeType
    var status: ChallengeStatus
    let startDate: Date
    let endDate: Date
    let targetMetric: ChallengeMetric
    let targetValue: Double
    let targetUnit: String
    var participantCount: Int
    let rules: String?
    let imageUrl: String?
    let createdBy: String
    let createdByName: String
    let clubId: String?
    var participationStatus: ParticipationStatus
    var userProgress: Double?
    let createdAt: Date

    enum CodingKeys: String, CodingKey {
        case id, title, description, challengeType, status, startDate, endDate, targetMetric, targetValue, targetUnit, participantCount, rules, imageUrl, createdBy, createdByName, clubId, participationStatus, userProgress, createdAt
    }

    init(
        id: String,
        title: String,
        description: String,
        challengeType: ChallengeType,
        status: ChallengeStatus,
        startDate: Date,
        endDate: Date,
        targetMetric: ChallengeMetric,
        targetValue: Double,
        targetUnit: String,
        participantCount: Int,
        rules: String?,
        imageUrl: String?,
        createdBy: String,
        createdByName: String,
        clubId: String?,
        participationStatus: ParticipationStatus,
        userProgress: Double?,
        createdAt: Date
    ) {
        self.id = id
        self.title = title
        self.description = description
        self.challengeType = challengeType
        self.status = status
        self.startDate = startDate
        self.endDate = endDate
        self.targetMetric = targetMetric
        self.targetValue = targetValue
        self.targetUnit = targetUnit
        self.participantCount = participantCount
        self.rules = rules
        self.imageUrl = imageUrl
        self.createdBy = createdBy
        self.createdByName = createdByName
        self.clubId = clubId
        self.participationStatus = participationStatus
        self.userProgress = userProgress
        self.createdAt = createdAt
    }

    static func == (lhs: Challenge, rhs: Challenge) -> Bool {
        lhs.id == rhs.id && lhs.participationStatus == rhs.participationStatus
    }

    var progressPercentage: Double {
        guard let progress = userProgress else { return 0 }
        return min((progress / targetValue) * 100, 100)
    }

    var daysRemaining: Int {
        let calendar = Calendar.current
        let components = calendar.dateComponents([.day], from: Date(), to: endDate)
        return components.day ?? 0
    }

    var isUpcoming: Bool {
        startDate > Date()
    }

    var isActive: Bool {
        Date() >= startDate && Date() <= endDate
    }

    var isCompleted: Bool {
        endDate < Date()
    }
}

// MARK: - Challenge Type

enum ChallengeType: String, CaseIterable, Codable {
    case distance
    case time
    case frequency
    case elevation
    case calories
    case streak

    var displayName: String {
        switch self {
        case .distance: return "Distance"
        case .time: return "Time"
        case .frequency: return "Frequency"
        case .elevation: return "Elevation"
        case .calories: return "Calories"
        case .streak: return "Streak"
        }
    }

    var icon: String {
        switch self {
        case .distance: return "arrow.right.arrow.left"
        case .time: return "stopwatch.fill"
        case .frequency: return "repeat"
        case .elevation: return "mountain.2.fill"
        case .calories: return "flame.fill"
        case .streak: return "calendar.badge.clock"
        }
    }

    var color: Color {
        switch self {
        case .distance: return .blue
        case .time: return .orange
        case .frequency: return .green
        case .elevation: return .brown
        case .calories: return .red
        case .streak: return .purple
        }
    }
}

// MARK: - Challenge Status

enum ChallengeStatus: String, CaseIterable, Codable {
    case upcoming
    case active
    case completed
    case cancelled
}

// MARK: - Challenge Metric

enum ChallengeMetric: String, CaseIterable, Codable {
    case distance
    case time
    case frequency
    case elevation
    case calories

    var unit: String {
        switch self {
        case .distance: return "km"
        case .time: return "min"
        case .frequency: return "sessions"
        case .elevation: return "m"
        case .calories: return "kcal"
        }
    }

    var displayName: String {
        switch self {
        case .distance: return "Distance"
        case .time: return "Time"
        case .frequency: return "Sessions"
        case .elevation: return "Elevation"
        case .calories: return "Calories"
        }
    }
}

// MARK: - Participation Status

enum ParticipationStatus: String, CaseIterable, Codable {
    case participating
    case notParticipating
    case invited
}

// MARK: - Challenge Participant

struct ChallengeParticipant: Identifiable, Codable {
    let id: String
    let name: String
    let avatarUrl: String?
    let progress: Double
    let rank: Int
    let joinedAt: Date
}

// MARK: - Leaderboard Entry

struct LeaderboardEntry: Identifiable, Codable {
    let id: String
    let position: Int
    let participantId: String
    let participantName: String
    let participantAvatarUrl: String?
    let progress: Double
    let progressPercentage: Double
}

// MARK: - Progress Submission

struct ProgressSubmission: Encodable {
    let metric: ChallengeMetric
    let value: Double
    let activityDate: Date
}

// MARK: - Create Challenge Request

struct CreateChallengeRequest: Encodable {
    let title: String
    let description: String
    let challengeType: ChallengeType
    let startDate: Date
    let endDate: Date
    let targetMetric: ChallengeMetric
    let targetValue: Double
    let rules: String?
    let clubId: String?
}

// MARK: - Update Challenge Request

struct UpdateChallengeRequest: Encodable {
    var title: String?
    var description: String?
    var challengeType: ChallengeType?
    var startDate: Date?
    var endDate: Date?
    var targetMetric: ChallengeMetric?
    var targetValue: Double?
    var rules: String?
    var status: ChallengeStatus?
}

// MARK: - Challenge Filter

struct ChallengeFilter: Encodable {
    var challengeType: ChallengeType?
    var status: ChallengeStatus?
    var participationStatus: ParticipationStatus?
    var clubId: String?
    var limit: Int
    var offset: Int

    init(
        challengeType: ChallengeType? = nil,
        status: ChallengeStatus? = nil,
        participationStatus: ParticipationStatus? = nil,
        clubId: String? = nil,
        limit: Int = 20,
        offset: Int = 0
    ) {
        self.challengeType = challengeType
        self.status = status
        self.participationStatus = participationStatus
        self.clubId = clubId
        self.limit = limit
        self.offset = offset
    }
}

// MARK: - API Response Types

struct ChallengeListResponse: Decodable {
    let challenges: [Challenge]
    let hasMore: Bool
}

struct ChallengeDetailResponse: Decodable {
    let challenge: Challenge
    let participants: [ChallengeParticipant]
}

struct CreateChallengeResponse: Decodable {
    let challenge: Challenge
}

struct UpdateChallengeResponse: Decodable {
    let challenge: Challenge
}

struct LeaderboardResponse: Decodable {
    let entries: [LeaderboardEntry]
    let userPosition: Int?
    let totalParticipants: Int
}

struct ParticipationResponse: Decodable {
    let success: Bool
    let challengeId: String
    let status: ParticipationStatus
}

struct ProgressResponse: Decodable {
    let success: Bool
    let challengeId: String
    let newProgress: Double
    let progressPercentage: Double
}