Add external links for tasks with plugin api

app/Core/ExternalLink/ExternalLinkManager.php

@@ -0,0 +1,171 @@
+<?php
+
+namespace Kanboard\Core\ExternalLink;
+
+use Kanboard\Core\Base;
+
+/**
+ * External Link Manager
+ *
+ * @package  externalLink
+ * @author   Frederic Guillot
+ */
+class ExternalLinkManager extends Base
+{
+    /**
+     * Automatic type value
+     *
+     * @var string
+     */
+    const TYPE_AUTO = 'auto';
+
+    /**
+     * Registered providers
+     *
+     * @access private
+     * @var array
+     */
+    private $providers = array();
+
+    /**
+     * Type chosen by the user
+     *
+     * @access private
+     * @var string
+     */
+    private $userInputType = '';
+
+    /**
+     * Text entered by the user
+     *
+     * @access private
+     * @var string
+     */
+    private $userInputText = '';
+
+    /**
+     * Register a new provider
+     *
+     * Providers are registered in a LIFO queue
+     *
+     * @access public
+     * @param  ExternalLinkProviderInterface $provider
+     * @return ExternalLinkManager
+     */
+    public function register(ExternalLinkProviderInterface $provider)
+    {
+        array_unshift($this->providers, $provider);
+        return $this;
+    }
+
+    /**
+     * Get provider
+     *
+     * @access public
+     * @param  string $type
+     * @throws ExternalLinkProviderNotFound
+     * @return ExternalLinkProviderInterface
+     */
+    public function getProvider($type)
+    {
+        foreach ($this->providers as $provider) {
+            if ($provider->getType() === $type) {
+                return $provider;
+            }
+        }
+
+        throw new ExternalLinkProviderNotFound('Unable to find link provider: '.$type);
+    }
+
+    /**
+     * Get link types
+     *
+     * @access public
+     * @return array
+     */
+    public function getTypes()
+    {
+        $types = array();
+
+        foreach ($this->providers as $provider) {
+            $types[$provider->getType()] = $provider->getName();
+        }
+
+        asort($types);
+
+        return array(self::TYPE_AUTO => t('Auto')) + $types;
+    }
+
+    /**
+     * Get dependency label from a provider
+     *
+     * @access public
+     * @param  string $type
+     * @param  string $dependency
+     * @return string
+     */
+    public function getDependencyLabel($type, $dependency)
+    {
+        $provider = $this->getProvider($type);
+        $dependencies = $provider->getDependencies();
+        return isset($dependencies[$dependency]) ? $dependencies[$dependency] : $dependency;
+    }
+
+    /**
+     * Find a provider that match
+     *
+     * @access public
+     * @throws ExternalLinkProviderNotFound
+     * @return ExternalLinkProviderInterface
+     */
+    public function find()
+    {
+        $provider = null;
+
+        if ($this->userInputType === self::TYPE_AUTO) {
+            $provider = $this->findProvider();
+        } else {
+            $provider = $this->getProvider($this->userInputType);
+            $provider->setUserTextInput($this->userInputText);
+        }
+
+        if ($provider === null) {
+            throw new ExternalLinkProviderNotFound('Unable to find link information from provided information');
+        }
+
+        return $provider;
+    }
+
+    /**
+     * Set form values
+     *
+     * @access public
+     * @param  array $values
+     * @return ExternalLinkManager
+     */
+    public function setUserInput(array $values)
+    {
+        $this->userInputType = empty($values['type']) ? self::TYPE_AUTO : $values['type'];
+        $this->userInputText = empty($values['text']) ? '' : trim($values['text']);
+        return $this;
+    }
+
+    /**
+     * Find a provider that user input
+     *
+     * @access private
+     * @return ExternalLinkProviderInterface
+     */
+    private function findProvider()
+    {
+        foreach ($this->providers as $provider) {
+            $provider->setUserTextInput($this->userInputText);
+
+            if ($provider->match()) {
+                return $provider;
+            }
+        }
+
+        return null;
+    }
+}