Add external links for tasks with plugin api

app/ExternalLink/WebLinkProvider.php

@@ -0,0 +1,77 @@
+<?php
+
+namespace Kanboard\ExternalLink;
+
+use Kanboard\Core\ExternalLink\ExternalLinkProviderInterface;
+
+/**
+ * Web Link Provider
+ *
+ * @package  externalLink
+ * @author   Frederic Guillot
+ */
+class WebLinkProvider extends BaseLinkProvider implements ExternalLinkProviderInterface
+{
+    /**
+     * Get provider name
+     *
+     * @access public
+     * @return string
+     */
+    public function getName()
+    {
+        return t('Web Link');
+    }
+
+    /**
+     * Get link type
+     *
+     * @access public
+     * @return string
+     */
+    public function getType()
+    {
+        return 'weblink';
+    }
+
+    /**
+     * Get a dictionary of supported dependency types by the provider
+     *
+     * @access public
+     * @return array
+     */
+    public function getDependencies()
+    {
+        return array(
+            'related' => t('Related'),
+        );
+    }
+
+    /**
+     * Return true if the provider can parse correctly the user input
+     *
+     * @access public
+     * @return boolean
+     */
+    public function match()
+    {
+        $startWithHttp = strpos($this->userInput, 'http://') === 0 || strpos($this->userInput, 'https://') === 0;
+        $validUrl = filter_var($this->userInput, FILTER_VALIDATE_URL);
+
+        return $startWithHttp && $validUrl;
+    }
+
+    /**
+     * Get the link found with the properties
+     *
+     * @access public
+     * @return ExternalLinkInterface
+     */
+    public function getLink()
+    {
+        $link = new WebLink($this->container);
+        $link->setUrl($this->userInput);
+
+        return $link;
+    }
+}