sql-request.js

const mysql = require('mysql');

var con = mysql.createConnection({
    host: "127.0.0.1",
    port: 3306,
    user: "hyperdrive",
    password: "hyper",
    database: 'hyperdrive',
    insecureAuth: true
});

/**
 * This function check if a user exist in the DB
 * @param {string} login This is the login of the user
 * @param {string} pass This is the password of the user
 */
function userExist(login, pass, callback){
    const q = `SELECT login, passwd FROM Users WHERE login='${login}' AND passwd='${pass}';`;
    con.query(q, function (err, result) {
        if (err) return false;
        if (result.length > 0) {
            console.log("user already exists");
            return callback({
                login: result[0]['login'],
                passwd: result[0]['passwd']
            });
        } else {
            console.log("user don't exists");
            return callback(false);
        }
    });
}

/**
 * This function insert a new user in the DB
 * @param {string} login This is the login of the user
 * @param {string} pass This is the password of the user
 */
function insertUser(login, passwd, callback){
    let q = `INSERT INTO Users VALUES ('${login}', '${passwd}');`;
    userExist(login, passwd, (userExist) => {
        if (!userExist){
            con.query(q, (err, res) => {
                if (err) return callback(false);
                if (!res) {console.log(res);return callback(false);}
                console.log("User", login, "inserted in the db");
                return callback(true);
            });
        }
    });
}

/**
 * This function add a new directory to a user
 * @param {string} path Path to add
 * @param {string} login User's path
 * @param {string} parent Parent of the new folder
 */
function addPath(path, login, parent, callback){
    let q = `INSERT INTO Paths VALUES ('${path}', '${login}', ${parent});`;
    con.query(q, function(err, res) {
        if (err) {
            console.log("Error while adding a new path");
            console.log(err);
            return callback(false);
        }
        console.log("New path", path, "added succesfully !");
        return callback(true);
    });
}

/**
 * This function add a user in the db it it doesn't already exists
 * It also add the default path of the user after inserting the new user.
 * @param {string} login This is the login of the user
 * @param {string} pass This is the password of the user
 */
function addUser(login, passwd) {

    insertUser(login, passwd, (insertOk) => {
        console.log(insertOk);
        if (insertOk) {
            addPath('/'+login, login, null, (res)=>{});
            console.log("Add ok");
        }
    });
}


/**
+----------------+-------+-----------+---------+-----------+
| paths          | login | parent    | file_id | file_name |
+----------------+-------+-----------+---------+-----------+
| /a/coucou      | a     | /a        | abnnnnn | deux      |
| /a/coucou      | a     | /a        | accb    | trois     |
| /a/coucou/test | a     | /a/coucou | NULL    | NULL      |
+----------------+-------+-----------+---------+-----------+
 */
async function changeDirectory(login, path, callback){
    q = `
        SELECT Paths.paths, login, parent, Files.file_id, Files.file_name
        FROM Paths
        LEFT JOIN Files ON Files.paths = Paths.paths
        WHERE Paths.login='${login}'
        AND Paths.paths='${path}'
        OR Paths.parent='${path}';`;

    con.query(q, (err, res) => {
        if (err) { 
            console.log("Error while loading the path");
            return callback(false, err);
        }

        let content = [];
        for (let i in res){
            content.push({
                paths: res[i].paths,
                login: res[i].login,
                parent: res[i].parent,
                file_id: res[i].file_id,
                file_name: res[i].file_name
            });
        }

        console.log(content);
        return callback(content, "Change dir success");
    });

    // return [
    //     {
    //         path: '/a/coucou',
    //         login: 'a',
    //         parent: '/a',
    //         file_id: 'abnnnnn',
    //         file_name: 'deux'
    //     },
    //     {
    //         path: '/a/coucou',
    //         login: 'a',
    //         parent: '/a',
    //         file_id: 'accb',
    //         file_name: 'trois'
    //     },
    //     {
    //         path: '/a/coucou/test',
    //         login: 'a',
    //         parent: '/a/coucou',
    //         file_id: 'NULL',
    //         file_name: 'NULL'
    //     }
    // ];
}

exports.addUser = addUser;
exports.addPath = addPath;
exports.changeDirectory = changeDirectory;