1 files changed, 103 insertions, 0 deletions
diff --git a/src/DotNetOpenAuth.Web/Clients/OAuth2/FacebookClient.cs b/src/DotNetOpenAuth.Web/Clients/OAuth2/FacebookClient.cs
new file mode 100644
index 0000000..e9e0b80
--- /dev/null
+++ b/src/DotNetOpenAuth.Web/Clients/OAuth2/FacebookClient.cs
@@ -0,0 +1,103 @@
+using System;
+using System.Collections.Generic;
+using System.Globalization;
+using System.Net;
+using System.Web;
+using DotNetOpenAuth.Web.Resources;
+
+namespace DotNetOpenAuth.Web.Clients
+{
+    internal sealed class FacebookClient : OAuth2Client
+    {
+        private const string AuthorizationEndpoint = "https://www.facebook.com/dialog/oauth";
+        private const string TokenEndpoint = "https://graph.facebook.com/oauth/access_token";
+
+        private readonly string _appId;
+        private readonly string _appSecret;
+
+        public FacebookClient(string appId, string appSecret)
+            : base("facebook")
+        {
+            if (String.IsNullOrEmpty(appId))
+            {
+                throw new ArgumentException(
+                    String.Format(CultureInfo.CurrentCulture, WebResources.Argument_Cannot_Be_Null_Or_Empty, "appId"),
+                    "appId");
+            }
+
+            if (String.IsNullOrEmpty("appSecret"))
+            {
+                throw new ArgumentException(
+                    String.Format(CultureInfo.CurrentCulture, WebResources.Argument_Cannot_Be_Null_Or_Empty, "appSecret"),
+                    "appSecret");
+            }
+
+            _appId = appId;
+            _appSecret = appSecret;
+        }
+
+        protected override Uri GetServiceLoginUrl(Uri returnUrl)
+        {
+            // Note: Facebook doesn't like us to url-encode the redirect_uri value
+            var builder = new UriBuilder(AuthorizationEndpoint);
+            builder.AppendQueryArguments(new Dictionary<string, string>
+            {
+                { "client_id", _appId },
+                { "redirect_uri", returnUrl.ToString() }
+            });
+            return builder.Uri;
+        }
+
+        protected override string QueryAccessToken(Uri returnUrl, string authorizationCode)
+        {
+            // Note: Facebook doesn't like us to url-encode the redirect_uri value
+            var builder = new UriBuilder(TokenEndpoint);
+            builder.AppendQueryArguments(new Dictionary<string, string>
+            {
+                { "client_id", _appId },
+                { "redirect_uri", returnUrl.ToString() },
+                { "client_secret", _appSecret },
+                { "code", authorizationCode }
+            });
+
+            using (WebClient client = new WebClient())
+            {
+                string data = client.DownloadString(builder.Uri);
+                if (String.IsNullOrEmpty(data))
+                {
+                    return null;
+                }
+
+                var parsedQueryString = HttpUtility.ParseQueryString(data);
+                if (parsedQueryString != null)
+                {
+                    return parsedQueryString["access_token"];
+                }
+            }
+            return null;
+        }
+
+        protected override IDictionary<string, string> GetUserData(string accessToken)
+        {
+            FacebookGraph graph;
+            var request = WebRequest.Create("https://graph.facebook.com/me?access_token=" + Uri.EscapeDataString(accessToken));
+            using (var response = request.GetResponse())
+            {
+                using (var responseStream = response.GetResponseStream())
+                {
+                    graph = JsonHelper.Deserialize<FacebookGraph>(responseStream);
+                }
+            }
+
+            // this dictionary must contains 
+            var userData = new Dictionary<string, string>();
+            userData.AddItemIfNotEmpty("id", graph.Id);
+            userData.AddItemIfNotEmpty("username", graph.Email);
+            userData.AddItemIfNotEmpty("name", graph.Name);
+            userData.AddItemIfNotEmpty("link", graph.Link == null ? null : graph.Link.ToString());
+            userData.AddItemIfNotEmpty("gender", graph.Gender);
+            userData.AddItemIfNotEmpty("birthday", graph.Birthday);
+            return userData;
+        }
+    }
+}