package Service;

import Base.User;
import Send_Email.Deal_i_code;
import Send_Email.Send_email;

import java.io.*;
import java.util.ArrayList;

public class User_service {
    private ArrayList<User> users;
    private final String base_dir="用户/";

    public User_service() {
        if (!load_users()){
            users=new ArrayList<>();
        }
    }

    public String register(String email){
        Deal_i_code.clean_all_codes();
        if (find_user(email)!=null){
            return "邮箱已被注册";
        }
        String judge_result=Send_email.judge_email_address(email);
        if (judge_result.equals("邮箱格式正确")){
            String code=Deal_i_code.generate_code(email);
            if (!Send_email.send_email(email,code)){
                return "邮件发送失败";
            }
            return "验证码已发送";
        }
        else{
            return judge_result;
        }
    }

    public String check_register(String email,String input_code,String pwd,String id){
        if (Deal_i_code.judge_code(email,input_code)){
            if (!User.check_password(pwd)){
                return "密码长6-20位，至少包含大小写字母和数字";
            }
            User new_one=new User(email);
            new_one.set_password(User.hash_pwd(pwd));
            new_one.set_id(id);
            if (find_user_i(id)!=null){
                return "用户名重复";
            }
            users.add(new_one);
            Deal_i_code.clean_all_codes();
            if (!save_users()){
                return "注册失败，请重试";
            }
            return "注册成功";
        }
        else {
            return "验证码不存在或不正确";
        }
    }

    public String login(String id,String pwd){
        User u=find_user_i(id);
        if (u==null){
            return "请先注册";
        }
        if (User.check_hash_pwd(pwd,u.get_password())){
            return "登陆成功";
        }
        return "密码有误";
    }

    public String change_pwd(String email, String oldPassword, String newPassword){
        User user=find_user(email);
        if (user == null) {
            return "用户不存在";
        }
        if (!User.check_hash_pwd(oldPassword,user.get_password())) {
            return "原密码不正确";
        }
        if (oldPassword.equals(newPassword)){
            return "新密码与原密码一致";
        }
        if (!User.check_password(newPassword)) {
            return "密码长6-20位，至少包含大小写字母和数字";
        }
        user.set_password(newPassword);
        if (save_users()) {
            return "修改成功";
        }
        return "修改失败";
    }

    public String Unregister(String email){
        User user=find_user(email);
        if (user!=null) {
            if (users.remove(user)) {
                if (save_users()) {
                    return "删除成功";
                }
            }
        }
        return "删除失败";
    }

    public User find_user(String email){
        for (User user : users) {
            if (user.get_email().equals(email)) {
                return user;
            }
        }
        return null;
    }

    public User find_user_i(String id){
        for (User user : users) {
            if (user.get_id().equals(id)) {
                return user;
            }
        }
        return null;
    }

    private boolean save_users(){
        File baseDir = new File(base_dir);
        if (!baseDir.exists()) {
            if (!baseDir.mkdirs()){
                return false;
            }
        }
        String file_path=base_dir+"用户信息.txt";
        try (PrintWriter writer = new PrintWriter(new FileWriter(file_path))) {
            if (users.isEmpty()){
                return true;
            }
            for (int i = 0; i < users.size(); i++) {
                writer.println(users.get(i).get_email()+" "+users.get(i).get_password()+" "+users.get(i).get_id());
                if (i < users.size() - 1) {
                    writer.println();
                }
            }
            return true;
        } catch (IOException e) {
            return false;
        }
    }

    private boolean load_users(){
        users=new ArrayList<>();
        String file_path=base_dir+"用户信息.txt";
        File file=new File(file_path);
        if (file.exists()){
            try (BufferedReader reader = new BufferedReader(new FileReader(file))) {
                String line;
                while ((line = reader.readLine()) != null) {
                    if (!line.trim().isEmpty()) {
                        String l=line.trim();
                        String[] parts=l.split(" ");
                        if (parts.length==3){
                            User temp=new User(parts[0]);
                            temp.set_password(parts[1]);
                            temp.set_id(parts[2]);
                            users.add(temp);
                        }
                    }
                }
                return true;
            } catch (IOException e) {
                return false;
            }
        }
        return false;
    }
}