const utils = require('../utils.js');
const path = require('path');
const auth = require('../utils/auth_utils');
const db = require('../utils/db');

db.createTable('users', [
    {name :'id', type: 'INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL'},
    {name :'name', type: 'VARCHAR(32) NOT NULL UNIQUE'},
    {name :'password', type: `VARCHAR(255) NOT NULL DEFAULT '123456'`},
    {name :'update_time', type: 'DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP'}
]);

function getUser(username) {
    let ret = db.selectData('users', null, `name='${username}'`);
    let info = db.info;
    return [ret, info];
}

function addUser(username, password) {
    let ret = db.insertData('users', {name: username, password: password});
    if (ret == false) {
        return [false, db.err.code];
    }
    let info = db.info;
    return [ret, info];
}

function getAllUsers() {
    let ret = db.selectData('users');
    let info = db.info;
    return [ret, info];
}

function checkAdmin(adminname, password) {
    if (adminname === (utils.env.ADMIN_LOGIN_NAME || 'admin') && 
    password === (utils.env.ADMIN_LOGIN_PASSWORD || 'admin') ) {
        const token = auth.generateToken({
            username: adminname,
            id: -1
        });
        return {...utils.json.success, data: {token: token, href: '/users/admin'}};
    } else {
        return {...utils.json.user_is_invalid};
    }
}

function checkUsers(username, password) {
    let [ret, info] = getUser(username);
    if (!ret) {
        return {...utils.json.user_is_invalid, data: info};
    } else if (!info || (Array.isArray(info) && info.length === 1)) {
        info = info[0];
        if (info.password !==  password) {
            return {...utils.json.user_is_invalid, data: 'password error'};
        } else {
            const token = auth.generateToken({
                username: username,
                id: info.id
            })
            return {...utils.json.success, data: {token: token, href: '/users'}};
        }
    } else {
        return {...utils.json.user_is_invalid, data: 'user name error'};
    }
}


function registerUsers(username, password) {
    let [ret, info] = addUser(username, password);
    if (!ret) {
        if (info === 'SQLITE_CONSTRAINT_UNIQUE') {
            info = 'user name is exist';
        } else {
            info = 'unknown error';
        }
        return {...utils.json.user_register_is_invalid, data: info};
    } else {
        return {...utils.json.success};
    }
}

function getAllUsersToJson(token) {
    if (typeof token === 'string') {
        return auth.verifyToken(token, (err) => {
            if (err) {
                return {...utils.json.token_is_invalid, data: info};
            }
            let [ret, info] = getAllUsers();
            if (ret) {
                return {...utils.json.success, data: info};
            } else {
                return {...utils.json.error};
            }
        });
    } else {
        return {...utils.json.token_is_invalid, data: null};
    }
}

const VIEWS_USERS_PATH = path.resolve(utils.VIEWS_PATH, 'users')

module.exports = { checkAdmin, checkUsers, registerUsers, getAllUsersToJson, VIEWS_USERS_PATH };