added facebook example (non-functional yet)

.gitignore

@@ -6,3 +6,4 @@ composer.lock
 public/config.php
 public/google/config.php
 public/github/config.php
+public/facebook/config.php

public/facebook/config.php.dist

@@ -0,0 +1,19 @@
+<?php
+return array(
+
+    'client_info' => array(
+        'client_id' => '<client ID>',
+        'redirect_uri' => '<redirect URI>',
+
+        'authorization_endpoint' => 'https://accounts.google.com/o/oauth2/auth',
+        'token_endpoint' => 'https://accounts.google.com/o/oauth2/token',
+        'user_info_endpoint' => 'https://www.googleapis.com/oauth2/v1/userinfo',
+
+        'authentication_info' => array(
+            'method' => 'client_secret_post',
+            'params' => array(
+                'client_secret' => '<client secret>'
+            )
+        )
+    )
+);

public/facebook/index.php

@@ -0,0 +1,30 @@
+<?php
+use InoOicClient\Flow\Basic;
+
+require __DIR__ . '/../../init_autoload.php';
+
+$config = require __DIR__ . '/config.php';
+
+$flow = new Basic($config);
+
+if (! isset($_GET['redirect'])) {
+
+    try {
+        $uri = $flow->getAuthorizationRequestUri('openid email profile');
+        _dump($uri);
+        printf("<pre>%s</pre><br>", $uri);
+        printf("<a href=\"%s\">Login</a>", $uri);
+    } catch (\Exception $e) {
+        _dump("$e");
+        printf("Exception during authorization URI creation: [%s] %s", get_class($e), $e->getMessage());
+    }
+} else {
+
+    try {
+        $userInfo = $flow->process();
+        printf("<pre>%s</pre>", print_r($userInfo, true));
+    } catch (\Exception $e) {
+        _dump("$e");
+        printf("Exception during user authentication: [%s] %s", get_class($e), $e->getMessage());
+    }
+}