using Couchbase.Lite;
using Couchbase.Lite.Auth;
using Couchbase.Lite.Util;
using Newtonsoft.Json;
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Net;
using System.Net.Http;
using System.Net.Http.Headers;
using System.Text;
using System.Threading;
using System.Threading.Tasks;

//To run tests:
//*] create bucket: syncdatasample
//*] create bucket: syncdatasample_sync
//*] use a the syncgatway.conf file like this one
//{
//    "adminInterface": ":4985",
//    "interface": ":4984",
//    "log":["HTTP", "Shadow", "CRUD", "Changes"],
//    "verbose": true,
//    "databases": {
//        "syncdatasampledb": {
//            "server": "http://localhost:8091",
//            "bucket": "syncdatasample_sync",
//            "shadow": {
//                   "server": "http://localhost:8091",
//                   "bucket": "syncdatasample"
//                },
//            "users": {
//                "GUEST": {
//                    "disabled": true,
//                    "admin_channels": ["*"]
//                }
//            },
//            "sync": `function(doc, oldDoc) {
//  channel(doc.channels);
//}`
//        }
//    }
//}

namespace SyncSample
{
    public class SyncSampleReplicationObserver
    {
        protected Manager _manager = null;
        protected Database _database = null;
        protected object _baseModel = null;
        protected int _syncPushPullNonBlockingTime = 60;
        private string _syncDatabaseBasePath = @"..\..\..\TestFolder\cbdb";
        private string _syncGatewayAdminURI = "http://localhost:4985";
        private string _syncGatewayURI = "http://localhost:4984";
        private string _syncDatabase = "syncdatasampledb";
        private string _syncUsername = "testuser";
        private string _syncPassword = "123456";
        private string[] _syncChannels = new string[] { };
        private GatewayUser[] users = new GatewayUser[] {
                new GatewayUser() {
                    name = "testuser",
                    password = "123456",
                    admin_channels = new string[] { "*" }
                }
            };

        /// <summary>
        /// Sample constructor
        /// </summary>
        public SyncSampleReplicationObserver()
        {
            _syncDatabaseBasePath = _syncDatabaseBasePath + "\\testdb";

            _manager = new Manager(new DirectoryInfo(_syncDatabaseBasePath), Manager.DefaultOptions);
            _database = _manager.GetDatabase(_syncDatabase.ToLower());

            InsertGatewayUsers(users);
        }

        /// <summary>
        /// Run a sample
        /// </summary>
        public void RunSample1()
        {
            string docId = "doctest:0001";
            string docJson = @"{
              'type': 'doctest',
              'channels' : [ 'userchannel-01' ],
              'item1': 'uno',
              'array1': [
                'i1',
                'i2'
              ]
            }";

            Dictionary<string, object> properties = JsonConvert.DeserializeObject<Dictionary<string, object>>(docJson);

            Document document = _database.GetDocument(docId);
            UnsavedRevision unsavedRevision = document.CreateRevision();
            unsavedRevision.SetUserProperties(properties);
            unsavedRevision.Save();

            Push();
            Pull(new string[] { });
        }

        /// <summary>
        /// Gateway user
        /// </summary>
        private struct GatewayUser
        {
            public string name;
            public string password;
            public string[] admin_channels;
        }

        /// <summary>
        /// Insert a sync gateway user using rest
        /// </summary>
        /// <param name="users"></param>
        private void InsertGatewayUsers(GatewayUser[] users)
        {
            foreach (GatewayUser user in users)
            {
                string userjson = JsonConvert.SerializeObject(user);
                HttpClient client = new HttpClient();
                string releteDocUrl = _syncGatewayAdminURI + "/" + _syncDatabase + "/_user/" + user.name;
                client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
                var request = new HttpRequestMessage(HttpMethod.Get, releteDocUrl);
                if (client.SendAsync(request).Result.StatusCode != HttpStatusCode.OK)
                {
                    request = new HttpRequestMessage(HttpMethod.Put, releteDocUrl);
                    request.Content = new StringContent(userjson, Encoding.UTF8, "application/json");
                    HttpResponseMessage response = client.SendAsync(request).Result;
                    if (response.StatusCode == HttpStatusCode.OK || response.StatusCode == HttpStatusCode.Created)
                        Console.WriteLine("SuccessFull inserted/updated user \"" + user.name + "\" in database \"" + _syncDatabase + "\"");
                    else
                        Console.WriteLine("Error inserting user \"" + user.name + "\" in database \"" + _syncDatabase + "\"");
                }
            }
        }

        /// <summary>
        /// Do a Pull
        /// </summary>
        /// <param name="channels"></param>
        /// <returns></returns>
        public bool Pull(string[] channels)
        {
            bool ret = false;

            Replication replication = _database.CreatePullReplication(new Uri(_syncGatewayURI + "/" + _syncDatabase));
            if (!String.IsNullOrEmpty(_syncUsername) && !String.IsNullOrEmpty(_syncPassword))
                replication.Authenticator = AuthenticatorFactory.CreateBasicAuthenticator(_syncUsername, _syncPassword);
            if (channels.Length > 0)
                replication.Channels = channels.AsEnumerable<string>();
            Log.D(_syncDatabase, "Pull replication start...");
            ret = RunReplication(replication);
            Log.D(_syncDatabase, "Pull replication ends.");

            return ret;
        }

        /// <summary>
        /// Do a Push
        /// </summary>
        /// <returns></returns>
        public bool Push()
        {
            bool ret = false;

            Replication replication = _database.CreatePushReplication(new Uri(_syncGatewayURI + "/" + _syncDatabase));
            if (!String.IsNullOrEmpty(_syncUsername) && !String.IsNullOrEmpty(_syncPassword))
                replication.Authenticator = AuthenticatorFactory.CreateBasicAuthenticator(_syncUsername, _syncPassword);
            Log.D(_syncDatabase, "Push replication start...");
            ret = RunReplication(replication);
            Log.D(_syncDatabase, "Push replication ends.");

            return ret;
        }

        /// <summary>
        /// Run Replication
        /// </summary>
        /// <param name="replication"></param>
        /// <returns></returns>
        private bool RunReplication(Replication replication)
        {
            bool ret = false;


            CountdownEvent replicationSignal = new CountdownEvent(1);
            ReplicationObserver replicationObserver = new ReplicationObserver(replicationSignal);
            replication.Changed += replicationObserver.Changed;
            replication.Start();
            if (!replicationSignal.Wait(TimeSpan.FromSeconds(_syncPushPullNonBlockingTime)))
            {
                Console.WriteLine("Timeout replication.");
                Log.D(_syncDatabase, "Timeout replication.");
                ret = false;
            }
            replication.Stop();

            return ret;
        }

    }
}