my-files-sample/Libraries/Sources/UseCases/Users/GetUserUseCase.swift

//
//  GetUserUseCase.swift
//  Login
//
//  Created by Javier Cicchelli on 12/12/2022.
//  Copyright © 2022 Röck+Cöde. All rights reserved.
//

import APIService
import DataModels
import DependencyInjection
import Dependencies
import KeychainStorage

public actor GetUserUseCase {
    
    // MARK: Properties
    
    private let apiService: APIService

    private var account: Account?
    
    // MARK: Initialisers
    
    public init(
        apiService: APIService,
        account: Account?
    ) {
        self.apiService = apiService
        self.account = account
    }
    
    // MARK: Functions
    
    public func callAsFunction() async throws -> User {
        guard let account else { throw GetUserError .accountNotFound }
        
        return try await getUser(
            username: account.username,
            password: account.password
        )
    }
    
    public func callAsFunction(
        username: String,
        password: String
    ) async throws -> User {
        let user = try await getUser(
            username: username,
            password: password
        )
        
        account = .init(
            username: username,
            password: password
        )
        
        return user
    }

}

// MARK: - Initialisers

public extension GetUserUseCase {
    init() {
        @Dependency(\.apiService) var apiService
        @KeychainStorage(key: .KeychainStorage.account) var account: Account?
        
        self.init(
            apiService: apiService,
            account: account
        )
    }
}

// MARK: - Helpers

private extension GetUserUseCase {
    func getUser(
        username: String,
        password: String
    ) async throws -> User {
        let me = try await apiService.getUser(
            credentials: .init(
                username: username,
                password: password
            )
        )
        
        return .init(
            profile: .init(
                firstName: me.firstName,
                lastName: me.lastName
            ),
            rootFolder: .init(
                id: me.rootItem.id,
                name: me.rootItem.name,
                lastModifiedAt: me.rootItem.lastModifiedAt
            )
        )
    }
}

// MARK: - Errors

public enum GetUserError: Error {
    case accountNotFound
}