GifBot.php

<?php

/**
 * Number of GIFs to reply with during #gifbomb. Slack will only open
 * up to 3 images automatically.
 */
define('GIFBOMB_COUNT', 3);

// ----- END OF CONFIGURATION ----- //

require_once 'GifBot/Gifable.php';
require_once 'GifBot/Giphy.php';
require_once 'GifBot/Gif.php';

$gif = new GifBot\Giphy;

// Get request
$trigger = trim($_POST['trigger_word']);
$term    = trim(substr($_POST['text'], strlen($trigger) + 1));

// Respond with random GIF if no search term is provided
if ($term == '') {
    sendResponse($gif->random()->getUrl());
}

// Search
$gifs  = $gif->search($term);
$count = count($gifs);

// Build reponse
$response = '';
if ($count > 0) {
    if ($trigger == '#bomb') {
        shuffle($gifs);

        $pullCount = min($count, GIFBOMB_COUNT);
        while ($pullCount > 0) {
            $index = rand(0, $count - 1);
            $response .= $gifs[$index]->getUrl() . "\n";

            // Prevent duplicates
            unset($gifs[$index]);
            $gifs = array_values($gifs);

            $pullCount--;
        }
    } else {
        $response = $gifs[rand(0, $count - 1)]->getUrl();
    }
} else {
    $response = "No image found for '" . $term . "'. Enjoy this random GIF instead. " . $gif->random()->getUrl();
}

// Respond
sendResponse($response);

exit;

/**
 * Send JSON Response
 *
 * @param $response
 */
function sendResponse($response)
{
    header('Content-Type: application/json');
    die(json_encode(array(
        'text' => $response
    )));
}