using Monaco.Editor;
using Monaco.Helpers;
using Nito.AsyncEx;
using System;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Windows.Foundation.Collections;
using Windows.UI.Xaml;

namespace Monaco
{
    partial class CodeEditor : IParentAccessorAcceptor
    {
        public bool IsSettingValue { get; set; }

        /// <summary>
        /// Get or Set the CodeEditor Text.
        /// </summary>
        public string Text
        {
            get { return (string)GetValue(TextProperty); }
            set { SetValue(TextProperty, value); }
        }

        // Using a DependencyProperty as the backing store for HorizontalLayout.  This enables animation, styling, binding, etc...
        private static readonly DependencyProperty TextPropertyField =
            DependencyProperty.Register("Text", typeof(string), typeof(CodeEditor), new PropertyMetadata(string.Empty, (d, e) => {
                if (!(d as CodeEditor).IsSettingValue)
                {
                    (d as CodeEditor)?.InvokeScriptAsync("updateContent", e.NewValue.ToString());
                }
            }));

        public static DependencyProperty TextProperty
        {
            get
            {
                return TextPropertyField;
            }
        }

        /// <summary>
        /// Get the current Primary Selected CodeEditor Text.
        /// </summary>
        public string SelectedText
        {
            get { return (string)GetValue(SelectedTextProperty); }
            set { SetValue(SelectedTextProperty, value); }
        }

        // Using a DependencyProperty as the backing store for HorizontalLayout.  This enables animation, styling, binding, etc...
        private static readonly DependencyProperty SelectedTextPropertyField =
            DependencyProperty.Register(nameof(SelectedText), typeof(string), typeof(CodeEditor), new PropertyMetadata(string.Empty, (d, e) => {
                if (!(d as CodeEditor).IsSettingValue)
                {
                    (d as CodeEditor)?.InvokeScriptAsync("updateSelectedContent", e.NewValue.ToString());
                }
            }));

        public static DependencyProperty SelectedTextProperty
        {
            get
            {
                return SelectedTextPropertyField;
            }
        }

        public Selection SelectedRange
        {
            get { return (Selection)GetValue(SelectedRangeProperty); }
            set { SetValue(SelectedRangeProperty, value); }
        }

        // Using a DependencyProperty as the backing store for SelectedRange.  This enables animation, styling, binding, etc...
        private static readonly DependencyProperty SelectedRangePropertyField =
            DependencyProperty.Register(nameof(SelectedRange), typeof(Selection), typeof(CodeEditor), new PropertyMetadata(null));

        public static DependencyProperty SelectedRangeProperty
        {
            get
            {
                return SelectedRangePropertyField;
            }
        }

        /// <summary>
        /// Set the Syntax Language for the Code CodeEditor.
        /// 
        /// Note: Most likely to change or move location.
        /// </summary>
        public string CodeLanguage
        {
            get { return (string)GetValue(CodeLanguageProperty); }
            set { SetValue(CodeLanguageProperty, value); }
        }

        // Using a DependencyProperty as the backing store for HorizontalLayout.  This enables animation, styling, binding, etc...
        private static readonly DependencyProperty CodeLanguagePropertyField =
            DependencyProperty.Register("CodeLanguage", typeof(string), typeof(CodeEditor), new PropertyMetadata("xml", (d, e) => {
                var editor = d as CodeEditor;

                if (editor.Options != null)
                {
                    // Will trigger its own update of Options, but need this for initialization changes.
                    editor.Options.Language = e.NewValue.ToString();
                }

                // TODO: Push this to Options property change check instead...
                // Changes to Language are ignored in Updated Options.
                // https://microsoft.github.io/monaco-editor/api/modules/monaco.editor.html#setmodellanguage.
                (d as CodeEditor)?.InvokeScriptAsync("updateLanguage", e.NewValue.ToString());
            }));

        internal static DependencyProperty CodeLanguageProperty
        {
            get
            {
                return CodeLanguagePropertyField;
            }
        }

        /// <summary>
        /// Get or set the CodeEditor Options.
        /// </summary>
        public IEditorConstructionOptions Options
        {
            get { return (IEditorConstructionOptions)GetValue(OptionsProperty); }
            set { SetValue(OptionsProperty, value); }
        }

        // Using a DependencyProperty as the backing store for Options.  This enables animation, styling, binding, etc...
        private static readonly DependencyProperty OptionsPropertyField =
            DependencyProperty.Register("Options", typeof(IEditorConstructionOptions), typeof(CodeEditor), new PropertyMetadata(new IEditorConstructionOptions(), (d, e) => {
                var value = e.NewValue as IEditorConstructionOptions;
                if (value != null)
                { 
                    var editor = d as CodeEditor;
                    if (editor != null)
                    {
                        editor.InvokeScriptAsync("updateOptions", value.ToJson());

                        // Register for sub-property changes on new object
                        value.PropertyChanged -= editor.Options_PropertyChanged;
                        value.PropertyChanged += editor.Options_PropertyChanged;
                    }
                }
            }));

        public static DependencyProperty OptionsProperty
        {
            get
            {
                return OptionsPropertyField;
            }
        }

        /// <summary>
        /// Get or Set the CodeEditor Text.
        /// </summary>
        public bool HasGlyphMargin
        {
            get { return (bool)GetValue(HasGlyphMarginProperty); }
            set { SetValue(HasGlyphMarginProperty, value); }
        }

        // Using a DependencyProperty as the backing store for HorizontalLayout.  This enables animation, styling, binding, etc...
        private static readonly DependencyProperty HasGlyphMarginPropertyField =
            DependencyProperty.Register("HasGlyphMargin", typeof(bool), typeof(CodeEditor), new PropertyMetadata(false, (d, e) => {
                (d as CodeEditor).Options.GlyphMargin = e.NewValue as bool?;
            }));

        public static DependencyProperty HasGlyphMarginProperty
        {
            get
            {
                return HasGlyphMarginPropertyField;
            }
        }

        /// <summary>
        /// Gets or sets text Decorations.
        /// </summary>
        public IObservableVector<IModelDeltaDecoration> Decorations
        {
            get { return (IObservableVector<IModelDeltaDecoration>)GetValue(DecorationsProperty); }
            set { SetValue(DecorationsProperty, value); }
        }

        private AsyncLock _mutexLineDecorations = new AsyncLock();

        // Using a DependencyProperty as the backing store for Options.  This enables animation, styling, binding, etc...
        private static readonly DependencyProperty DecorationsPropertyField =
            DependencyProperty.Register("Decorations", typeof(IModelDeltaDecoration), typeof(CodeEditor), new PropertyMetadata(null, async (d, e) => {
                var editor = d as CodeEditor;
                if (editor != null)
                {
                    // We only want to do this one at a time per editor.
                    using (await editor._mutexLineDecorations.LockAsync())
                    {
                        var old = e.OldValue as IObservableVector<IModelDeltaDecoration>;
                        // Clear out the old line decorations if we're replacing them or setting back to null
                        if ((old != null && old.Count > 0) ||
                             e.NewValue == null)
                        {
                            await editor.DeltaDecorationsHelperAsync(null);
                        }
                        var value = e.NewValue as IObservableVector<IModelDeltaDecoration>;

                        if (value != null)
                        {
                            if (value.Count > 0)
                            {
                                await editor.DeltaDecorationsHelperAsync(value.ToArray());
                            }

                            value.VectorChanged -= editor.Decorations_VectorChanged;
                            value.VectorChanged += editor.Decorations_VectorChanged;
                        }
                    }
                }
            }));

        private async void Decorations_VectorChanged(IObservableVector<IModelDeltaDecoration> sender, IVectorChangedEventArgs @event)
        {
            if (sender != null)
            {
                // Need to recall mutex as this is called from outside of this initial callback setting it up.
                using (await _mutexLineDecorations.LockAsync())
                {
                    await DeltaDecorationsHelperAsync(sender.ToArray());
                }
            }
        }

        public static DependencyProperty DecorationsProperty
        {
            get
            {
                return DecorationsPropertyField;
            }
        }

        /// <summary>
        /// Gets or sets the hint Markers.
        /// Note: This property is a helper for <see cref="SetModelMarkersAsync(string, IMarkerData[])"/>; use this property or the method, not both.
        /// </summary>
        public IObservableVector<IMarkerData> Markers
        {
            get { return (IObservableVector<IMarkerData>)GetValue(MarkersProperty); }
            set { SetValue(MarkersProperty, value); }
        }

        private AsyncLock _mutexMarkers = new AsyncLock();

        // Using a DependencyProperty as the backing store for Options.  This enables animation, styling, binding, etc...
        private static readonly DependencyProperty MarkersPropertyField =
            DependencyProperty.Register("Markers", typeof(IMarkerData), typeof(CodeEditor), new PropertyMetadata(null, async (d, e) => {
                var editor = d as CodeEditor;
                if (editor != null)
                {
                    // We only want to do this one at a time per editor.
                    using (await editor._mutexMarkers.LockAsync())
                    {
                        var old = e.OldValue as IObservableVector<IMarkerData>;
                        // Clear out the old markers if we're replacing them or setting back to null
                        if ((old != null && old.Count > 0) ||
                             e.NewValue == null)
                        {
                            // TODO: Can I simplify this in this case?
                            await editor.SetModelMarkersAsync("CodeEditor", Array.Empty<IMarkerData>());
                        }
                        var value = e.NewValue as IObservableVector<IMarkerData>;

                        if (value != null)
                        {
                            if (value.Count > 0)
                            {
                                await editor.SetModelMarkersAsync("CodeEditor", value.ToArray());
                            }

                            value.VectorChanged -= editor.Markers_VectorChanged;
                            value.VectorChanged += editor.Markers_VectorChanged;
                        }
                    }
                }
            }));

        private async void Markers_VectorChanged(IObservableVector<IMarkerData> sender, IVectorChangedEventArgs @event)
        {
            if (sender != null)
            {
                // Need to recall mutex as this is called from outside of this initial callback setting it up.
                using (await _mutexMarkers.LockAsync())
                {
                    await SetModelMarkersAsync("CodeEditor", sender.ToArray());
                }
            }
        }

        public static DependencyProperty MarkersProperty
        {
            get
            {
                return MarkersPropertyField;
            }
        }
    }
}