using FluentFTP;
using Microsoft.WindowsAzure.Storage.Blob;
using System;
using System.Collections.Generic;
using System.IO;
using System.IO.Compression;
using System.Linq;
using System.Text;
using System.Threading;
using System.Threading.Tasks;
using Tango.Core;
using Tango.Core.DB;
using Tango.Core.Helpers;
using Tango.Core.IO;
using Tango.PMR.Synchronization;
using Tango.PPC.Common.Application;
using Tango.Settings;
using Tango.SQLExaminer;
using Tango.Transport.Web;

namespace Tango.PPC.Common.MachineUpdate
{
    public class MachineUpdateManager : ExtendedObject, IMachineUpdateManager
    {
        private IPPCApplicationManager _app_manager;

        #region Events

        /// <summary>
        /// Occurs when there is a text log message available.
        /// </summary>
        public event EventHandler<string> ProgressLog;

        /// <summary>
        /// Occurs when the <see cref="CurrentStep" /> has changed.
        /// </summary>
        public event EventHandler<MachineUpdateSteps> ProgressStep;

        #endregion

        #region Properties

        private MachineUpdateSteps _currentStep;
        /// <summary>
        /// Gets the current setup step.
        /// </summary>
        public MachineUpdateSteps CurrentStep
        {
            get { return _currentStep; }
            set
            {
                if (_currentStep != value)
                {
                    _currentStep = value;
                    RaisePropertyChangedAuto();
                    ProgressStep?.Invoke(this, _currentStep);
                    LogManager.Log("Machine Setup Manager Step: " + value.ToString());
                }
            }
        }

        private double _downloadProgress;
        /// <summary>
        /// Gets the downloading packages step progress.
        /// </summary>
        public double DownloadingPackagesProgress
        {
            get { return _downloadProgress; }
            private set { _downloadProgress = value; RaisePropertyChangedAuto(); }
        }

        private String _updatingPackagesStatus;
        /// <summary>
        /// Gets the downloading packages step status.
        /// </summary>
        public String DownloadingPackagesStatus
        {
            get { return _updatingPackagesStatus; }
            set { _updatingPackagesStatus = value; RaisePropertyChangedAuto(); }
        }

        #endregion

        #region Constructors

        /// <summary>
        /// Initializes a new instance of the <see cref="MachineUpdateManager"/> class.
        /// </summary>
        /// <param name="applicationManager">The application manager.</param>
        public MachineUpdateManager(IPPCApplicationManager applicationManager)
        {
            _app_manager = applicationManager;
        }

        #endregion

        #region Public Methods

        /// <summary>
        /// Performs a machine setup using the specified serial number and machine service address.
        /// </summary>
        /// <param name="serialNumber">The serial number.</param>
        /// <param name="machineServiceAddress">The machine service address.</param>
        /// <returns></returns>
        public Task<MachineUpdateResult> Update(string serialNumber, string machineServiceAddress)
        {
            return Task.Factory.StartNew<MachineUpdateResult>(() =>
            {

                LogManager.Log($"Starting machine update for serial number {serialNumber}...");

                //Connect to machine service and get matching packages for this machine.
                CurrentStep = MachineUpdateSteps.DownloadingPackage;
                DownloadingPackagesProgress = 0;
                DownloadingPackagesStatus = "Connecting to machine service...";

                LogManager.Log($"Connecting to machine service on {machineServiceAddress}...");

                DownloadUpdateRequest request = new DownloadUpdateRequest();
                request.SerialNumber = serialNumber;

                DownloadUpdateResponse update_response = null;

                using (var http = new ProtoWebClient())
                {
                    update_response = http.Post<DownloadUpdateRequest, DownloadUpdateResponse>(machineServiceAddress + "/api/Synchronization/MachineUpdate", request).Result;
                }

                LogManager.Log($"Machine update response received: {Environment.NewLine}{update_response.ToJsonString()}");

                //Create temporary folders for packages.
                var _newPackageTempFolder = TemporaryManager.CreateFolder();
                _newPackageTempFolder.Persist = true;

                LogManager.Log($"Temporary package folder created: {_newPackageTempFolder}.");

                //Download software package.
                var tempFile = TemporaryManager.CreateFile(".zip");

                LogManager.Log($"Temporary package zip file created: {tempFile}.");

                DownloadingPackagesStatus = "Downloading software package...";

                LogManager.Log("Downloading software package...");

                long fileSize = 0;
                DownloadingPackagesProgress = 0;

                using (FileStreamWrapper fs = new FileStreamWrapper(tempFile.Path, FileMode.Create, (current) =>
                {
                    InvokeUINow(() =>
                    {
                        DownloadingPackagesProgress = ((double)current / (double)fileSize) * 100d;
                    });
                }))
                {
                    LogManager.Log($"Connecting to storage blob with address {update_response.BlobAddress}");
                    CloudBlockBlob blob = new CloudBlockBlob(new Uri(update_response.BlobAddress));
                    LogManager.Log("Fetching blob attributes...");
                    blob.FetchAttributes();
                    fileSize = blob.Properties.Length;
                    LogManager.Log("Download size: " + fileSize + " bytes.");
                    LogManager.Log("Starting blob download...");
                    blob.DownloadToStream(fs);
                }

                LogManager.Log("Extracting downloaded zip file...");
                //Extract software package.
                ZipFile.ExtractToDirectory(tempFile, _newPackageTempFolder);


                LogManager.Log("Copying latest updater utility to application path...");
                //Copy new updater utility to app path.
                File.Copy(Path.Combine(_newPackageTempFolder, "Tango.PPC.Updater.exe"), Path.Combine(PathHelper.GetStartupPath(), "Tango.PPC.Updater.exe"), true);


                //Synchronize database
                CurrentStep = MachineUpdateSteps.SynchronizingSchema;

                String db_name = "Tango";
                String localAddress = SettingsManager.Default.GetOrCreate<CoreSettings>().DataSource.Address;
                String remote_address = update_response.DbAddress;

                LogManager.Log($"Synchronizing database '{remote_address}\\{db_name}' => '{localAddress}\\{db_name}'...");

                LogManager.Log("Initializing database manager...");
                DbManager db = DbManager.FromAddressAndName(localAddress, db_name);

                LogManager.Log("Checking Tango database exists on the local machine...");
                if (!db.Exists(db_name))
                {
                    throw new InvalidProgramException("Database tango does not exists.");
                }

                LogManager.Log("Disposing database manager.");
                db.Dispose();

                LogManager.Log($"Initializing {nameof(ExaminerSequenceConfigurationRunner)}...");

                ExaminerSequenceConfigurationRunner runner = new ExaminerSequenceConfigurationRunner(
                    Path.Combine(_newPackageTempFolder, "Update Scripts", "config.xml"),
                    Path.Combine(_newPackageTempFolder, "Update Scripts"),
                    new ExaminerSequenceDataSource()
                    {
                        Address = remote_address,
                        DataBaseName = db_name,
                        IntegratedSecurity = false,
                        UserName = update_response.DbUserName,
                        Password = update_response.DbPassword,
                    },
                    new ExaminerSequenceDataSource()
                    {
                        Address = localAddress,
                        DataBaseName = db_name,
                        IntegratedSecurity = true,
                    }, serialNumber);

                runner.Log += (x, msg) =>
                {
                    LogManager.Log(msg);
                    ProgressLog?.Invoke(this, msg);
                };

                runner.ScriptExecuting += (x, item) =>
                {
                    LogManager.Log($"Executing script {item.ToString()}...");

                    if (item.Type == ExaminerSequenceItemType.Data && item.RequiresSerialNumber)
                    {
                        CurrentStep = MachineUpdateSteps.SynchronizingMachineConfiguration;
                    }
                    else if (item.Type == ExaminerSequenceItemType.Data)
                    {
                        CurrentStep = MachineUpdateSteps.SynchronizingData;
                    }
                };

                LogManager.Log("Starting synchronization process...");

                try
                {
                    runner.Run().Wait();
                    LogManager.Log("Synchronization completed successfully!");
                }
                catch (Exception ex)
                {
                    throw LogManager.Log(ex, "Setup manager error while trying to synchronize database.");
                }

                return new MachineUpdateResult()
                {
                    UpdatePackagePath = _newPackageTempFolder,
                };
            });
        }

        /// <summary>
        /// Checks if any update are available for the specified machine serial number.
        /// </summary>
        /// <param name="serialNumber">The serial number.</param>
        /// <param name="machineServiceAddress">The machine service address.</param>
        /// <returns></returns>
        public Task<CheckForUpdateResponse> CheckForUpdate(string serialNumber, string machineServiceAddress)
        {
            return Task.Factory.StartNew<CheckForUpdateResponse>(() =>
            {
                LogManager.Log($"Connecting to machine service on {machineServiceAddress}...");
                LogManager.Log($"Checking if updates available...");

                CheckForUpdateRequest request = new CheckForUpdateRequest();
                request.SerialNumber = serialNumber;
                request.Version = _app_manager.Version.ToString();

                CheckForUpdateResponse update_response = null;

                using (var http = new ProtoWebClient())
                {
                    update_response = http.Post<CheckForUpdateRequest, CheckForUpdateResponse>(machineServiceAddress + "/api/Synchronization/CheckForUpdate", request).Result;
                }

                LogManager.Log($"Check for update response received: {Environment.NewLine}{update_response.ToJsonString()}");

                return update_response;
            });
        }

        /// <summary>
        /// Updates all the "overwrite-able" database tables.
        /// </summary>
        /// <param name="serialNumber">The serial number.</param>
        /// <param name="machineServiceAddress">The machine service address.</param>
        /// <returns></returns>
        public Task UpdateDB(DbCompareResult dbCompareResult)
        {
            return Task.Factory.StartNew(() =>
            {
                LogManager.Log("Starting database update...");

                LogManager.Log("Looking for OverrideData script on application path...");

                String config_file = Path.Combine(PathHelper.GetStartupPath(), "Update Scripts", "OverrideData.xml");

                if (!File.Exists(config_file))
                {
                    config_file = Path.Combine(PathHelper.GetStartupPath(), "Provision Scripts", "OverrideData.xml");
                }

                if (!File.Exists(config_file))
                {
                    throw LogManager.Log(new FileNotFoundException("Could not locate OverrideData.xml file on application folder."));
                }

                UpdateDBResponse update_response = dbCompareResult.UpdateDBResponse;

                String db_name = "Tango";
                String localAddress = SettingsManager.Default.GetOrCreate<CoreSettings>().DataSource.Address;
                String remote_address = update_response.DbAddress;

                LogManager.Log($"Overriding database static tables '{remote_address}\\{db_name}' => '{localAddress}\\{db_name}'...");

                ExaminerConfigurationBuilder builder = new ExaminerConfigurationBuilder(config_file);
                builder.SetSourceServer(remote_address, db_name, false, update_response.DbUserName, update_response.DbPassword);
                builder.SetTargetServer(localAddress, db_name, true);
                builder.Synchronize();

                var config = builder.Build();

                ExaminerProcess process = new ExaminerProcess(config, ExaminerProcessType.Data);
                process.Progress += (x, msg) =>
                {
                    LogManager.Log(msg);
                };

                LogManager.Log("Starting synchronization process...");

                try
                {
                    var result = process.Execute().Result;

                    if (result.ExitCode != ExaminerProcessExitCode.Success)
                    {
                        throw LogManager.Log(new InvalidDataException(String.Format("OverrideData script has terminated with exit code '{0}'.", result.ExitCode)));
                    }

                    LogManager.Log("Synchronization completed successfully!");
                }
                catch (Exception ex)
                {
                    throw LogManager.Log(ex, "Setup manager error while trying to update the database.");
                }
            });
        }

        /// <summary>
        /// Checks whether it is necessary to updates all the "overwrite-able" database tables.
        /// </summary>
        /// <param name="serialNumber">The serial number.</param>
        /// <param name="machineServiceAddress">The machine service address.</param>
        /// <returns></returns>
        public Task<DbCompareResult> UpdateDBCheck(string serialNumber, string machineServiceAddress)
        {
            return Task.Factory.StartNew<DbCompareResult>(() =>
            {
                LogManager.Log($"Checking if database update is required for serial number {serialNumber}...");

                LogManager.Log("Looking for OverrideData script on application path...");

                String config_file = Path.Combine(PathHelper.GetStartupPath(), "Update Scripts", "OverrideData.xml");

                if (!File.Exists(config_file))
                {
                    config_file = Path.Combine(PathHelper.GetStartupPath(), "Provision Scripts", "OverrideData.xml");
                }

                if (!File.Exists(config_file))
                {
                    throw LogManager.Log(new FileNotFoundException("Could not locate OverrideData.xml file on application folder."));
                }

                LogManager.Log($"Connecting to machine service on {machineServiceAddress}...");

                UpdateDBRequest request = new UpdateDBRequest();
                request.SerialNumber = serialNumber;

                UpdateDBResponse update_response = null;

                using (var http = new ProtoWebClient())
                {
                    update_response = http.Post<UpdateDBRequest, UpdateDBResponse>(machineServiceAddress + "/api/Synchronization/UpdateDB", request).Result;
                }

                LogManager.Log($"Update DB response received: {Environment.NewLine}{update_response.ToJsonString()}");

                String db_name = "Tango";
                String localAddress = SettingsManager.Default.GetOrCreate<CoreSettings>().DataSource.Address;
                String remote_address = update_response.DbAddress;

                LogManager.Log($"Comparing database static tables '{remote_address}\\{db_name}' => '{localAddress}\\{db_name}'...");

                var report_file = TemporaryManager.CreateFile(".xml");

                ExaminerConfigurationBuilder builder = new ExaminerConfigurationBuilder(config_file);
                builder.SetSourceServer(remote_address, db_name, false, update_response.DbUserName, update_response.DbPassword);
                builder.SetTargetServer(localAddress, db_name, true);
                builder.SetReportFile(report_file);

                var config = builder.Build();

                ExaminerProcess process = new ExaminerProcess(config, ExaminerProcessType.Data);
                process.Progress += (x, msg) =>
                {
                    LogManager.Log(msg);
                };

                LogManager.Log("Starting comparison process...");
                LogManager.Log("Generating report on " + report_file);

                try
                {
                    var result = process.Execute().Result;

                    if (result.ExitCode != ExaminerProcessExitCode.Success)
                    {
                        throw LogManager.Log(new InvalidDataException(String.Format("OverrideData script has terminated with exit code '{0}'.", result.ExitCode)));
                    }

                    LogManager.Log("Comparison completed successfully!");
                    LogManager.Log("Loading report file...");

                    ExaminerDataReport report = ExaminerDataReport.FromFile(report_file);
                    report_file.Delete();

                    LogManager.Log("Comparison summary: \n" + report.Totals.ToJsonString());

                    return new DbCompareResult()
                    {
                        RequiresUpdate = report.HasDifferences,
                        UpdateDBResponse = update_response,
                    };
                }
                catch (Exception ex)
                {
                    throw LogManager.Log(ex, "Update manager error while trying to compare the database.");
                }
            });
        }

        #endregion
    }
}