package com.nju.edu.gitlab.service.impl;

import com.nju.edu.gitlab.service.api.UserService;
import com.nju.edu.gitlab.service.vo.GitlabUser;
import com.nju.edu.gitlab.util.ApplicationProperties;
import com.nju.edu.gitlab.util.Tools;
import com.nju.edu.gitlab.web.dto.ChangePasswordDTO;
import com.nju.edu.gitlab.web.dto.GitlabUserDTO;
import org.gitlab4j.api.GitLabApi;
import org.gitlab4j.api.GitLabApiException;
import org.gitlab4j.api.models.*;
import org.gitlab4j.api.models.ImpersonationToken.Scope;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Component;

@Component
public class UserServiceImpl implements UserService {
    private final GitLabApi gitlabApi;

    private final String gitlabHost;
    private final String token;

    @Autowired
    public UserServiceImpl(ApplicationProperties properties) {
        this.gitlabHost=properties.getHost();
        this.token= properties.getToken();
        this.gitlabApi = new GitLabApi(this.gitlabHost, this.token);
    }

    @Override
    public synchronized GitlabUser createGitlabUser(GitlabUserDTO gitlabUserDTO) throws GitLabApiException {
        String username=gitlabUserDTO.getUsername();
        String password=gitlabUserDTO.getPassword();
        String email= gitlabUserDTO.getEmail();
        User user=new User();
        user.setName(username);
        user.setUsername(username);
        user.setEmail(email);
        user.setSkipConfirmation(true);
        user= gitlabApi.getUserApi().createUser(user, password, true);
        GitlabUser gitlabUser=new GitlabUser();
        gitlabUser.setUserId(user.getId());
        gitlabUser.setNamespaceId(fetchNameSpaceId(username));
        gitlabUser.setToken(createToken(user.getId()));
        return gitlabUser;
    }

    @Override
    public synchronized boolean changePassword(ChangePasswordDTO changePasswordDTO) throws GitLabApiException {
        int userId=changePasswordDTO.getUserId();
        String password=changePasswordDTO.getPassword();
        User user=gitlabApi.getUserApi().getUser(userId);
        gitlabApi.getUserApi().updateUser(user,password);
        return true;
    }

    @Override
    public synchronized boolean deleteUser(int userId) throws GitLabApiException {
        gitlabApi.getUserApi().deleteUser(userId);
        return true;
    }

    private String createToken(int userId) throws GitLabApiException {
        Scope[] scopes = new Scope[]{Scope.API};
        ImpersonationToken token;
        token = gitlabApi.getUserApi().createImpersonationToken(userId, "AES-" + Tools.randomUUID(), null, scopes);
        return token.getToken();
    }

    private Integer fetchNameSpaceId(String username) throws GitLabApiException {
        Namespace namespace;
        namespace = gitlabApi.getNamespaceApi().findNamespaces(username)
                .stream()
                .filter(ns -> "user".equals(ns.getKind()))
                .reduce((ns1, ns2) -> ns1.getId() > ns2.getId() ? ns1 : ns2)
                .orElse(null);
        return namespace != null ? namespace.getId() : null;
    }
}