// 
// Copyright (c) 2014 .NET Foundation
//
// Permission is hereby granted, free of charge, to any person obtaining
// a copy of this software and associated documentation files (the
// "Software"), to deal in the Software without restriction, including
// without limitation the rights to use, copy, modify, merge, publish,
// distribute, sublicense, and/or sell copies of the Software, and to
// permit persons to whom the Software is furnished to do so, subject to
// the following conditions:
// 
// The above copyright notice and this permission notice shall be
// included in all copies or substantial portions of the Software.
// 
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
//
//
// Copyright (c) 2014 Couchbase, Inc. All rights reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file
// except in compliance with the License. You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software distributed under the
// License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
// either express or implied. See the License for the specific language governing permissions
// and limitations under the License.
//using System;
using System.Collections.Generic;
using Couchbase.Lite.Auth;
using Couchbase.Lite.Util;
using Sharpen;

namespace Couchbase.Lite.Auth
{
    /// <summary>Authenticator impl that knows how to do facebook auth</summary>
    /// <exclude></exclude>
    public class FacebookAuthorizer : Authorizer
    {
        public const string LoginParameterAccessToken = "access_token";

        public const string QueryParameter = "facebookAccessToken";

        public const string QueryParameterEmail = "email";

        private static IDictionary<IList<string>, string> accessTokens;

        private string emailAddress;

        public FacebookAuthorizer(string emailAddress)
        {
            this.emailAddress = emailAddress;
        }

        public override bool UsesCookieBasedLogin()
        {
            return true;
        }

        public override IDictionary<string, string> LoginParametersForSite(Uri site)
        {
            IDictionary<string, string> loginParameters = new Dictionary<string, string>();
            try
            {
                string accessToken = AccessTokenForEmailAndSite(this.emailAddress, site);
                if (accessToken != null)
                {
                    loginParameters.Put(LoginParameterAccessToken, accessToken);
                    return loginParameters;
                }
                else
                {
                    return null;
                }
            }
            catch (Exception e)
            {
                Log.E(Log.TagSync, "Error looking login parameters for site", e);
            }
            return null;
        }

        public override string LoginPathForSite(Uri site)
        {
            return "/_facebook";
        }

        public static string RegisterAccessToken(string accessToken, string email, string
             origin)
        {
            lock (typeof(FacebookAuthorizer))
            {
                IList<string> key = new AList<string>();
                key.AddItem(email);
                key.AddItem(origin);
                if (accessTokens == null)
                {
                    accessTokens = new Dictionary<IList<string>, string>();
                }
                Log.V(Log.TagSync, "FacebookAuthorizer registering key: %s", key);
                accessTokens.Put(key, accessToken);
                return email;
            }
        }

        public static string AccessTokenForEmailAndSite(string email, Uri site)
        {
            try
            {
                IList<string> key = new AList<string>();
                key.AddItem(email);
                key.AddItem(site.ToExternalForm().ToLower());
                Log.V(Log.TagSync, "FacebookAuthorizer looking up key: %s from list of access tokens"
                    , key);
                return accessTokens.Get(key);
            }
            catch (Exception e)
            {
                Log.E(Log.TagSync, "Error looking up access token", e);
            }
            return null;
        }
    }
}
