<?php
/**
 * Created by PhpStorm.
 * User: leanderschmedemann
 * Date: 27/03/2017
 * Time: 14:07
 */

    require_once('includes.inc.php');
    $data = '';
    $error = 0;
    $values = null;
    $uid = isset($_GET['uid']) ? $_GET['uid'] : '';
    $length = isset($_GET['length']) ? $_GET['length'] : '';
    $length = (($length === '0') || ($length && gettype(+$length) == 'integer')) ? +$_GET['length'] : 10;
    $db = new Database();
    $questions_count = $db->query('SELECT COUNT(*) FROM "Questions"')['data'][0]['count'];

    // Return $count random, non repeating numbers in range from $min to $max.
    function random_numbers($min, $max, $count){
        $numbers = range($min, $max);
        shuffle($numbers);
        return array_slice($numbers, 0, $count-1);
    }

    if($uid == '') {
        $error = 12103;
    } else if($length == 0) {
        $error = 12101;
    } else if($length > $questions_count) {
        $error = 12102;
        $values = array($questions_count);
    } else {
        // Delete existing game for user.
        if($db->query('SELECT EXISTS (SELECT 1 FROM "Games" WHERE "ID" = $1)', array($uid))['data'][0]['exists'] == 't') {
            $db->query('DELETE FROM "Games" WHERE "ID" = $1', array($uid));
        }
        // Create new game for user.
        $db->query('INSERT INTO "Games" ("ID") VALUES ($1)', array($uid));
        print_r(pg_last_error());
        // Find questions for new game and insert into table.
        $questions = random_numbers(0, $questions_count-1, $length);
        foreach($questions as $question) {
            $q = $db->query('SELECT "ID" FROM "Questions" OFFSET $1 LIMIT 1', array($question))['data'][0]['ID'];
            $db->query('INSERT INTO "GamesQuestions" ("Games_ID", "Questions_ID") VALUES ($1, $2)', array($uid, $q));
        }
    }

    $next_question = Question::get_next_question($db, $uid);
    $data = array('next' => $next_question);

    $response = Database::create_response($data, $error, $values);
    print_r($response);
?>