//Main API for managing user permissions database
const express=require('express');
const cors= require('cors');
const bodyParser= require('body-parser');
const knex= require ('knex');
const { check, validationResult } = require('express-validator');

const app=express();
//Enabling CORS
app.use(cors());
//Enabling req body parsing
app.use(bodyParser.json());
//Connection with database -locally
const db = knex ({
    client: 'pg',
    connection: {
      host : '127.0.0.1',
      user : 'postgres',
      password : '0904',
      database : 'testdb'
    }
});

//Requiremenst for JSON endpoint calls
const addusertogroup= require('./endpoints/addusertogroup');
const cleargroup= require('./endpoints/cleargroup');
const addpermission= require('./endpoints/addpermission');

//Checking basics
app.get('/', (req, res) => {
     res.send("Work in progress...");
})

//Call for adding a user to a group
app.post('/addusertogroup', [
    //Simple input validation with express-validator
    check('reqgroup').isAlphanumeric().isLength({min:3}),
    check('requser').isAlphanumeric().isLength({min:3})
], (req, res) => {
    const errors = validationResult(req)
    if (!errors.isEmpty()) {
      return res.status(422).json('Incorrect input data. Can not add an user.');
    }
    addusertogroup.handleAddUserToGroup(req, res, db)});

//Call for deleting all users from group
app.delete('/cleargroup', (req,res) => {
    cleargroup.handleClearGroup(req, res, db)
});

//Call for adding a permission to a user or group
app.post('/addpermission', [
    //Simple input validation with express-validator
    check('reqowner').isAlphanumeric().isLength({min:3}),
    check('reqobjname').isAlphanumeric().isLength({min:3}),
    check('reqtype').isAlphanumeric().isLength({min:3}),
    check('reqownertype').custom((value, {req, loc, pah}) => {
        if (value.toLowerCase()==='group' || value.toLowerCase()==='user') {
            return value;
        }
        else {
            return false;
        }
    })
], (req, res) => {
    const errors = validationResult(req)
    if (!errors.isEmpty()) {
      return res.status(422).json('Incorrect input data. Can not add a permission.');
    }
    addpermission.handleAddPermission(req, res, db)});


//Listening on local port 3000 -temporary, to be changed to env Var
app.listen(3000, () => {
    console.log(`App is running on port 3000`);
})