using System;
using System.Collections.Specialized;
using System.ComponentModel;
using System.Configuration;
using System.Globalization;
using System.Linq;
using DTS.Common.Classes;
using DTS.Common.Enums;
using DTS.Common.Events;
using DTS.Common.Base;
using Prism.Events;
using Prism.Regions;
using Microsoft.Windows.Controls.Ribbon;

//https://fluent.codeplex.com/SourceControl/latest
namespace DTS.Common.RibbonControl
{
    /// <summary>
    /// Enables use of the <see cref="Microsoft.Windows.Controls.Ribbon.Ribbon"/> in a Prism <see cref="RegionNames.RibbonRegion"/>.
    /// To install Ribbon Controls Library, run the following command in the Package Manager Console - Install-Package RibbonControlsLibrary
    /// or install from https://www.microsoft.com/en-us/download/details.aspx?id=11877
    /// </summary>
    /// <remarks>
    /// The <see cref="RibbonRegionAdapter"/> adapts controls derived from the class <see cref="Microsoft.Windows.Controls.Ribbon.Ribbon"/> such as <see cref="RibbonTab"/>.
    /// </remarks>
    public class RibbonRegionAdapter : RegionAdapterBase<Ribbon>, IDisposable
    {
        /// <summary>
        /// Injected region manager
        /// </summary>
        private readonly IRegionManager _regionManager;

        /// <summary>
        /// Injected event aggregator
        /// </summary>
        private readonly IEventAggregator _eventAggregator;

        private static readonly object Lock = new object();

        /// <summary>
        /// Creates a new instance of the <see cref="RibbonRegionAdapter"/> class.
        /// </summary>
        /// <param name="regionBehaviorFactory">Allows the registration of the default set of RegionBehaviors.</param>
        /// <param name="regionManager">Obtained reference of the region manager by using dependency injection.</param>
        /// <param name="eventAggregator">Obtained reference of the revent aggregator by using dependency injection.</param>
        public RibbonRegionAdapter(IRegionBehaviorFactory regionBehaviorFactory, IRegionManager regionManager, IEventAggregator eventAggregator)
            : base(regionBehaviorFactory)
        {
            _regionManager = regionManager;
            _eventAggregator = eventAggregator;
            _eventAggregator.GetEvent<TabControlSelectionChanged>().Subscribe(OnTabControlSelectionChanged);
        }

        /// <summary>
        /// Adapts the <see cref="Microsoft.Windows.Controls.Ribbon.Ribbon"/> to an <see cref="IRegion"/>. 
        /// </summary>
        /// <param name="region">The new region being used.</param>
        /// <param name="regionTarget">The object to adapt.</param>
        protected override void Adapt(IRegion region, Ribbon regionTarget)
        {
            if (regionTarget == null)
                throw new ArgumentNullException("regionTarget");

            region.ActiveViews.CollectionChanged += (o, e) =>
            {
                switch (e.Action)
                {
                    case NotifyCollectionChangedAction.Add:
                        foreach (var item in e.NewItems.OfType<RibbonTab>())
                            AddRibbonTabToRegion(item, regionTarget);
                        foreach (var item in e.NewItems.OfType<RibbonApplicationMenu>())
                            AddApplicationMenuToRegion(item, regionTarget);

                        break;
                    case NotifyCollectionChangedAction.Remove:
                        foreach (var item in e.OldItems.OfType<RibbonTab>())
                            RemoveRibbonTabFromRibbonRegion(item, regionTarget);

                        break;
                }
            };
        }

        private void AddRibbonTabToRegion(RibbonTab ribbonTab, Ribbon regionTarget)
        {
            lock (Lock)
            {
                if (string.IsNullOrEmpty(ribbonTab.Uid))
                    ribbonTab.Uid = Guid.NewGuid().GetHashCode().ToString(CultureInfo.InvariantCulture);

                regionTarget.Items.Add(ribbonTab);
            }

            regionTarget.Items.SortDescriptions.Add(new SortDescription("TabIndex", ListSortDirection.Ascending));

            var config = ConfigurationManager.AppSettings["DefaultRibbonTab"];
            if (!string.IsNullOrWhiteSpace(config))
            {
                ribbonTab.IsSelected = ribbonTab.Header.ToString().ToLower() == config.ToLower();
            }
        }

        private void AddApplicationMenuToRegion(RibbonApplicationMenu applicationMenu, Ribbon regionTarget)
        {
            if (string.IsNullOrEmpty(applicationMenu.Uid))
                applicationMenu.Uid = Guid.NewGuid().GetHashCode().ToString(CultureInfo.InvariantCulture);

            regionTarget.ApplicationMenu = applicationMenu;
        }

        private void RemoveRibbonTabFromRibbonRegion(RibbonTab ribbonTab, Ribbon regionTarget)
        {
            regionTarget.Items.Remove(ribbonTab);
        }

        private void OnTabControlSelectionChanged(TabControlSelectionEventArgs e)
        {
            if (e.Operation == TabControlOperation.RemovedItem) return;

            var view = e.Item as IBaseView;
            if (view == null) return;
            if (view.DataContext == null) return;

            var ribbonTabInfo = view.DataContext as IRibbonTabInfoProvider;
            if (ribbonTabInfo == null) return;
            if (string.IsNullOrEmpty(ribbonTabInfo.RibbonTabUid)) return;

            var currentTab = _regionManager.Regions[RegionNames.RibbonRegion].ActiveViews.OfType<RibbonTab>().FirstOrDefault(t => t.IsSelected);
            if (currentTab == null) return;

            if (ribbonTabInfo.RibbonTabUid != currentTab.Uid)
            {
                var selectedTab = _regionManager.Regions[RegionNames.RibbonRegion].ActiveViews.OfType<RibbonTab>().FirstOrDefault(t => t.Uid == ribbonTabInfo.RibbonTabUid);

                if (selectedTab != null)
                    selectedTab.IsSelected = true;
            }
        }

        /// <summary>
        /// Template method to create a new instance of <see cref="Prism.Regions.IRegion"/>
        /// that will be used to adapt the object.
        /// </summary>
        /// <returns>
        /// A new instance of <see cref="Prism.Regions.IRegion"/>.
        /// </returns>
        protected override IRegion CreateRegion()
        {
            return new AllActiveRegion();
        }

        #region IDisposable Support

        private bool _disposedValue; // To detect redundant calls.

        /// <summary>
        /// Disposes the object.
        /// </summary>
        /// <param name="disposing">True if called by the public Dispose method.</param>
        protected virtual void Dispose(bool disposing)
        {
            if (!_disposedValue)
            {
                if (_eventAggregator != null)
                    _eventAggregator.GetEvent<TabControlSelectionChanged>().Unsubscribe(OnTabControlSelectionChanged);
            }
            _disposedValue = true;
        }

        /// <summary>
        /// Disposes the object.
        /// </summary>
        public void Dispose()
        {
            // Do not change this code.  Put cleanup code in Dispose(bool disposing) above.
            Dispose(true);
            GC.SuppressFinalize(this);
        }

        /// <summary>
        /// Object finalizer.
        /// </summary>
        ~RibbonRegionAdapter()
        {
            Dispose(false);
        }

        #endregion
    }
}