03082020-Githawk-2-solution.swift

private struct FetchSuccess {
    let asignees: [IssueAssigneeViewModel]
    let nextPage: Int?
}

private func fetch(owner: String,
                   repo: String,
                   pageNumber: Int,
                   completion: @escaping (Result<FetchSuccess>) -> Void) {

    let request = V3AssigneesRequest(owner: owner,
                                     repo: repo,
                                     page: pageNumber)
    
    client.client.send(request) { result in
        
        switch result {
            
        case .success(let response):
            
            let sortedUsers = response.data
                .sorted {
                    if $0.login == self.client.userSession?.username {
                        return true
                    } else {
                        return $0.login.caseInsensitiveCompare($1.login) == .orderedAscending
                    }
                }.map { IssueAssigneeViewModel(login: $0.login, avatarURL: $0.avatarUrl) }
            
            let fetchSuccess = FetchSuccess(asignees: sortedUsers,
                                            nextPage: response.next)
            completion(.success(fetchSuccess))
            
        case .failure(let error):
            completion(.error(error))
        }
    }
}