first commit

code/web/backend/application/model/CaptchaModel.php

@@ -0,0 +1,46 @@
+<?php
+
+/**
+ * Class CaptchaModel
+ *
+ * This model class handles all the captcha stuff.
+ * Currently this uses the excellent Captcha generator lib from https://github.com/Gregwar/Captcha
+ * Have a look there for more options etc.
+ */
+class CaptchaModel
+{
+	/**
+	 * Generates the captcha, "returns" a real image, this is why there is header('Content-type: image/jpeg')
+	 * Note: This is a very special method, as this is echoes out binary data.
+	 */
+	public static function generateAndShowCaptcha()
+	{
+		// create a captcha with the CaptchaBuilder lib (loaded via Composer)
+		$captcha = new Gregwar\Captcha\CaptchaBuilder;
+		$captcha->build(
+			Config::get('CAPTCHA_WIDTH'),
+			Config::get('CAPTCHA_HEIGHT')
+		);
+
+		// write the captcha character into session
+		Session::set('captcha', $captcha->getPhrase());
+
+		// render an image showing the characters (=the captcha)
+		header('Content-type: image/jpeg');
+		$captcha->output();
+	}
+
+	/**
+	 * Checks if the entered captcha is the same like the one from the rendered image which has been saved in session
+	 * @param $captcha string The captcha characters
+	 * @return bool success of captcha check
+	 */
+	public static function checkCaptcha($captcha)
+	{
+		if ($captcha == Session::get('captcha')) {
+			return true;
+		}
+
+		return false;
+	}
+}