polls

<?php

/*
CREATE TABLE IF NOT EXISTS `polls_answers` (
  `answer_id` mediumint(9) NOT NULL AUTO_INCREMENT,
  `pollid` mediumint(9) DEFAULT NULL,
  `text` varchar(255) DEFAULT NULL,
  `votes` mediumint(9) DEFAULT '0',
  PRIMARY KEY (`answer_id`),
  KEY `answer_id` (`answer_id`,`pollid`)
) ENGINE=InnoDB  DEFAULT CHARSET=utf8



CREATE TABLE IF NOT EXISTS `polls_votes` (
  `ip` varchar(15) NOT NULL,
  `pollid` mediumint(9) DEFAULT NULL,
  KEY `ip` (`ip`,`pollid`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
*/


require 'configurationInit.php';

// fetch user's IP address
$ip = $db->real_escape_string($_SERVER['REMOTE_ADDR']);


/**
 * Returns json-encoded poll's choices and results
 * @param int $pollid Poll's ID
 * @param bool $return either return value(true) or output value(false)
 * @return json json-encoded poll results (text and number of votes)
 */
function show_poll_results($pollid, $return = false)
{

    $votes = get_array("SELECT `text`, `votes` FROM `polls_answers` WHERE `pollid`=".intval($pollid));

    if($return) return json_encode($votes);

    // output the resulting javascript
    send_user_script($pollid, $votes);

}



function send_user_script(&$pollid, &$data, $action = 'show_results')
{
    // outputs the javascript with the data
    echo
    "
    var polls_data = polls_data || [];
    polls_data[$pollid] = { action: '$action', data: ".json_encode($data)."};
    ";
}



// Submit poll vote
if(
        isset($_POST['poll'], $_POST['selection']) &&
        ($pollid    = filter_input(INPUT_POST, 'poll',      FILTER_VALIDATE_INT)) &&
        ($selection = filter_input(INPUT_POST, 'selection', FILTER_VALIDATE_INT))
):


    // check whether the user had already voted to this poll
    $has_votedR = $db->query("SELECT `ip` FROM `polls_votes` WHERE `ip`='$ip' AND `pollid`=$pollid LIMIT 1");
    $has_voted = $has_votedR->num_rows > 0;
    $has_votedR->close();

    // if the user had already voted for this poll - abort
    if($has_voted)
    {
        show_poll_results($pollid, true);
        die();
    }

    if
    (
        $db->query("UPDATE `polls_answers` SET `votes` = `votes`+1
                    WHERE `answer_id`=$selection AND `pollid`=$pollid")
    )
    {
        $db->query("INSERT INTO `polls_votes` (`ip`, `pollid`) VALUES ('$ip', $pollid) ");
    }

    // send the user the results of the poll including his own result
    die(show_poll_results($pollid, true));



elseif
(
    isset($_GET['show_results']) &&
    ($pollid = filter_input(INPUT_GET, 'show_results', FILTER_VALIDATE_INT))
):


    show_poll_results($pollid);



else: // Show poll questions



    $pollid = filter_input(INPUT_GET, 'pollid', FILTER_VALIDATE_INT);
    if(!$pollid || $pollid < 1 ) die('hm');

    // if the user has already voted for this poll - show poll results
    // if he hadn't yet - show the possible choices to vote for
    $has_votedR = $db->query("SELECT `ip` FROM `polls_votes` WHERE `ip`='$ip' AND `pollid`=$pollid LIMIT 1");
    $has_voted = $has_votedR->num_rows > 0;
    $has_votedR->close();

    if($has_voted)
    {
        show_poll_results($pollid, false);
        die();
    }


    // fetch poll's data
        // fetch poll's data
    $pollR = $db->query("SELECT * FROM `polls_answers` WHERE `pollid` = $pollid");
    if($pollR->num_rows < 1) die();

    //generate array of options with corresponding id's
    while( $answer = $pollR->fetch_assoc() )
    {
        $options[$answer['answer_id']] = $answer['text'];
    }
    $pollR->close();

    // output the resulting javascript
    send_user_script($pollid, $options, $action = 'run_poll');

endif;