//
//  AuthService.swift
//  Snail
//

import Foundation

nonisolated struct User: Codable, Identifiable, Hashable, Sendable {
    let id: String
    let name: String
    let email: String
    let emailVerified: Bool
    let image: String?
    let createdAt: Date

    /// При входе по коду better-auth создаёт пользователя с пустым именем.
    var displayName: String {
        name.trimmingCharacters(in: .whitespaces).isEmpty ? email : name
    }

    var initials: String {
        let source = name.trimmingCharacters(in: .whitespaces).isEmpty ? email : name
        let letters = source
            .split(whereSeparator: { $0 == " " || $0 == "@" || $0 == "." })
            .prefix(2)
            .compactMap(\.first)
        return String(letters).uppercased()
    }
}

/// Эндпоинты better-auth (плагин emailOTP) и профиля.
nonisolated struct AuthService: Sendable {
    private let client: APIClient

    init(client: APIClient = APIClient()) {
        self.client = client
    }

    func sendSignInCode(to email: String) async throws {
        let _: SuccessResponse = try await client.send(
            "POST",
            "auth/email-otp/send-verification-otp",
            body: ["email": email, "type": "sign-in"]
        )
    }

    func signIn(email: String, code: String) async throws -> User {
        let response: UserResponse = try await client.send(
            "POST",
            "auth/sign-in/email-otp",
            body: ["email": email, "otp": code]
        )
        return response.user
    }

    /// Текущий пользователь или nil, если сессии нет.
    func currentUser() async throws -> User? {
        do {
            let response: Envelope<UserResponse> = try await client.send("GET", "users/me")
            return response.data.user
        } catch APIError.unauthorized {
            return nil
        }
    }

    func signOut() async {
        let _: SuccessResponse? = try? await client.send("POST", "auth/sign-out", body: [:])
        client.clearCookies()
    }
}

private nonisolated struct SuccessResponse: Decodable {
    let success: Bool
}

private nonisolated struct UserResponse: Decodable {
    let user: User
}