Add a check for a compressed snap data

Snap data is compressed when a video is sent with an overlay (text, drawings or filters)
 - Check for compression
 - unCompress
 - Return both files as an array with keys (overlay, and m4v).

Author: hisham-albeik

src/snapchat.php

@@ -665,6 +665,11 @@ public function unblock($username) {
 	 *
 	 * @return mixed
 	 *   The snap data or FALSE on failure.
+	 *     Snap data can returned as an Array of more than one file.
+	 * 	@return: Array (
+	 * 			overlay => binary_file_content,
+	 * 			M4V     =>binary_m4v_content
+	 * 			)
 	 */
 	public function getMedia($id) {
 		// Make sure we're logged in and have a valid access token.
@@ -695,6 +700,18 @@ public function getMedia($id) {
 			if (parent::isMedia(substr($result, 0, 2))) {
 				return $result;
 			}
+			
+			//When a snapchat video is sent with "text" or overlay
+			//the overlay is a transparent PNG file PKZIPPED together
+			//with the M4V file.
+			//First two bytes "PK" x50x4B; thus the previous will
+			//fail and would've returned "FALSE".
+			if (parent::isCompressed(substr($result, 0, 2))) {
+				//Uncompress
+				@result_array = parent::unCompress($result);
+				//Return Media and Overlay
+				return @result_array;
+			}
 		}
 
 		return FALSE;