using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Tango.BL.Entities;
using Tango.Core.Commands;
using Tango.Integration.Operation;
using Tango.PPC.Common;
using Tango.PPC.Common.Navigation;
using Tango.PPC.Jobs.AppBarItems;
using Tango.PPC.Jobs.AppButtons;
using Tango.PPC.Jobs.Dialogs;
using Tango.PPC.Jobs.NavigationObjects;
using Tango.PPC.Jobs.Views;

namespace Tango.PPC.Jobs.ViewModels
{
    /// <summary>
    /// Represents the job progress view model.
    /// </summary>
    /// <seealso cref="Tango.PPC.Common.PPCViewModel" />
    public class JobProgressViewVM : PPCViewModel
    {
        private StopPrintingButton _stop_job_btn;
        private JobHandler _handler;

        #region Properties

        private Job _job;
        /// <summary>
        /// Gets or sets the job.
        /// </summary>
        public Job Job
        {
            get { return _job; }
            set { _job = value; RaisePropertyChangedAuto(); }
        }

        private RunningJobStatus _runningJobStatus;
        /// <summary>
        /// Gets or sets the running job status.
        /// </summary>
        public RunningJobStatus RunningJobStatus
        {
            get { return _runningJobStatus; }
            set { _runningJobStatus = value; RaisePropertyChangedAuto(); }
        }

        #endregion

        #region Commands

        /// <summary>
        /// Gets or sets the go to job command.
        /// </summary>
        /// <value>
        /// The go to job command.
        /// </value>
        public RelayCommand GoToJobCommand { get; set; }

        #endregion

        public JobProgressViewVM()
        {
            _stop_job_btn = new StopPrintingButton();
            _stop_job_btn.Pressed += _stop_job_btn_Pressed;

            GoToJobCommand = new RelayCommand(GoToJob);
        }

        private void _stop_job_btn_Pressed()
        {
            if (_handler != null)
            {
                _handler.Cancel();
            }
        }

        private void GoToJob()
        {
            NavigationManager.NavigateWithObject<JobsModule, JobView, JobNavigationObject>(new JobNavigationObject() { Job = _handler.Job });
            NavigationManager.ClearHistoryExcept<JobsView>();
        }

        #region Override Methods

        /// <summary>
        /// Called when the application has been started.
        /// </summary>
        public override void OnApplicationStarted()
        {
            MachineProvider.MachineOperator.PrintingStarted += MachineOperator_PrintingStarted;
        }

        /// <summary>
        /// Called when the navigation system has navigated from this VM view.
        /// </summary>
        public override void OnNavigatedFrom()
        {
            base.OnNavigatedFrom();

            if (MachineProvider.MachineOperator.IsPrinting && _handler != null && !_handler.IsCanceled)
            {
                NotificationProvider.PushAppBarItem<JobProgressAppBarItem>().Pressed += (_, __) =>
                {
                    NotificationProvider.CurrentAppBarItem.Close();
                    NavigationManager.NavigateTo<JobsModule>(nameof(JobProgressView));
                };
            }
        }

        /// <summary>
        /// Called when the navigation system has navigated to this VM view.
        /// </summary>
        public override void OnNavigatedTo()
        {
            base.OnNavigatedTo();

            if (NotificationProvider.HasAppBarItem && NotificationProvider.CurrentAppBarItem is JobProgressAppBarItem)
            {
                NotificationProvider.CurrentAppBarItem.Close();
            }

            _stop_job_btn.Push();
        }

        #endregion

        #region Event Handlers

        /// <summary>
        /// Handles the PrintingStarted event of the MachineOperator.
        /// </summary>
        /// <param name="sender">The source of the event.</param>
        /// <param name="e">The <see cref="PrintingEventArgs"/> instance containing the event data.</param>
        private void MachineOperator_PrintingStarted(object sender, PrintingEventArgs e)
        {
            _handler = e.JobHandler;
            Job = e.Job;
            e.JobHandler.StatusChanged += JobHandler_StatusChanged;
            e.JobHandler.SpoolChangeRequired += JobHandler_SpoolChangeRequired;
            e.JobHandler.Stopped += JobHandler_Stopped;

            _stop_job_btn.Push();
        }

        /// <summary>
        /// Handles the SpoolChangeRequired event of the JobHandler.
        /// </summary>
        /// <param name="sender">The source of the event.</param>
        /// <param name="e">The <see cref="SpoolChangeRequiredEventArgs"/> instance containing the event data.</param>
        private void JobHandler_SpoolChangeRequired(object sender, SpoolChangeRequiredEventArgs e)
        {
            InvokeUI(async () =>
            {
                if ((await NotificationProvider.ShowDialog(new SpoolChangeViewVM(e))).DialogResult)
                {
                    e.Confirm();
                }
                else
                {
                    e.Abort();
                }
            });
        }

        /// <summary>
        /// Handles the Stopped event of the JobHandler.
        /// </summary>
        /// <param name="sender">The source of the event.</param>
        /// <param name="e">The <see cref="EventArgs"/> instance containing the event data.</param>
        private void JobHandler_Stopped(object sender, EventArgs e)
        {
            if (NotificationProvider.HasAppBarItem && NotificationProvider.CurrentAppBarItem is JobProgressAppBarItem)
            {
                NotificationProvider.CurrentAppBarItem.Close();
            }

            _stop_job_btn.Pop();
        }

        /// <summary>
        /// Handles the JobHandler StatusChanged event.
        /// </summary>
        /// <param name="sender">The sender.</param>
        /// <param name="e">The e.</param>
        private void JobHandler_StatusChanged(object sender, RunningJobStatus e)
        {
            InvokeUI(() =>
            {
                RunningJobStatus = e;
            });
        }

        #endregion
    }
}