import Foundation
import SwiftUI

@MainActor
class FamilyPlanViewModel: ObservableObject {
    @Published var familyPlan: FamilyPlan?
    @Published var leaderboard: [FamilyLeaderboardEntry] = []
    @Published var selectedMetric: LeaderboardMetric = .distance
    @Published var isLoading: Bool = false
    @Published var error: FamilyPlanError?

    private let service: FamilyPlanServiceProtocol

    init(service: FamilyPlanServiceProtocol = FamilyPlanService()) {
        self.service = service
    }

    func fetchFamilyPlan() async {
        isLoading = true
        error = nil
        defer { isLoading = false }

        do {
            familyPlan = try await service.getFamilyPlan()
        } catch let error as FamilyPlanError {
            self.error = error
        } catch {
            print("Failed to fetch family plan: \(error)")
        }
    }

    func inviteMember(email: String, name: String) async {
        guard let plan = familyPlan, plan.availableSlots > 0 else { return }

        let request = InviteMemberRequest(email: email, name: name)
        do {
            try await service.inviteMember(request: request)
            objectWillChange.send()
        } catch {
            print("Failed to invite member: \(error)")
        }
    }

    func removeMember(id: String) async {
        guard let index = familyPlan?.members.firstIndex(where: { $0.id == id }) else { return }
        do {
            try await service.removeMember(id: id)
            familyPlan?.members.remove(at: index)
            objectWillChange.send()
        } catch {
            print("Failed to remove member: \(error)")
        }
    }

    func fetchLeaderboard() async {
        isLoading = true
        error = nil
        defer { isLoading = false }

        do {
            leaderboard = try await service.getLeaderboard(metric: selectedMetric)
        } catch let error as FamilyPlanError {
            self.error = error
        } catch {
            print("Failed to fetch leaderboard: \(error)")
        }
    }

    var activeMembers: [FamilyMember] {
        familyPlan?.members.filter { $0.role == .member || $0.role == .owner } ?? []
    }

    var pendingInvites: [FamilyMember] {
        familyPlan?.members.filter { $0.role == .pending } ?? []
    }

    var metrics: [LeaderboardMetric] { LeaderboardMetric.allCases }
}