import { OkPacket } from "mysql";
import cyber from "../2-utils/cyber";
import dal from "../2-utils/dal";
import CredentialsModel from "../4-models/credentials-model";
import { UnauthorizedError, ValidationError } from "../4-models/errors-model";
import Role from "../4-models/role-model";
import UserModel from "../4-models/user-model";


async function register(user: UserModel): Promise<string> {
    const errors = user.validateRegister();
    if (errors) {
        throw new ValidationError(errors);
    }
    user.username = user.username.toLowerCase();
    if(await isUsernameExist(user.username)) {
        throw new ValidationError(`This username: "${user.username}" already exists.`)
    }
    const sql = `INSERT INTO users(FirstName, LastName, Username, Password)
                 VALUES('${user.firstName}', '${user.lastName}', '${user.username}', '${user.password}')`;
    const result: OkPacket = await dal.fetchUsers(sql);
    user.id = result.insertId;
    user.role = Role.User;
    console.log(user);
    
    const token = cyber.getNewToken(user);
    return token;
}

async function login(credential: CredentialsModel): Promise<string> {
    const errors = credential.logInValidation();
    if (errors) {
        throw new ValidationError(errors);
    }
    credential.username = credential.username.toLowerCase();
    const sql = `SELECT UserID, Username,Password, Role 
                 FROM users 
                 WHERE Username LIKE '${credential.username}' 
                 AND Password LIKE '${credential.password}';`;
    const result = await dal.fetchUsers(sql);
    if(result[0] === undefined) {
        throw new UnauthorizedError("Incorrect username or password")
    }
    const token = cyber.getNewToken(result);
    return token;
}

async function isUsernameExist(username: string): Promise<boolean> {
    const sql = `SELECT COUNT(Username) as count 
                 FROM users 
                 WHERE Username = '${username}'`;
    const result = await dal.fetchVacations(sql);
    const count = result[0].count;
    return count > 0
}


export default {
    register,
    login
}