// Copyright (c) AlphaSierraPapa for the SharpDevelop Team (for details please see \doc\copyright.txt)
// This code is distributed under the GNU LGPL (for details please see \doc\license.txt)

using System;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Threading;
using ICSharpCode.AvalonEdit;
using ICSharpCode.SharpDevelop;
using ICSharpCode.SharpDevelop.Dom;
using ICSharpCode.SharpDevelop.Dom.NRefactoryResolver;
using ICSharpCode.SharpDevelop.Editor;
using ICSharpCode.SharpDevelop.Editor.CodeCompletion;
using ICSharpCode.SharpDevelop.Project;
using ICSharpCode.SharpDevelop.Services;

namespace Debugger.AddIn.Pads.Controls
{
	public class AutoCompleteTextBox : UserControl
	{
		TextEditor editor;
		ITextEditor editorAdapter;
		
		public static readonly DependencyProperty TextProperty =
			DependencyProperty.Register("Text", typeof(string), typeof(AutoCompleteTextBox),
			                            new FrameworkPropertyMetadata(string.Empty, FrameworkPropertyMetadataOptions.BindsTwoWayByDefault, TextChanged));
		
		public static readonly DependencyProperty IsEditableProperty =
			DependencyProperty.Register("IsEditable", typeof(bool), typeof(AutoCompleteTextBox),
			                            new FrameworkPropertyMetadata(true, IsEditableChanged));	
		
		public string Text {
			get { return (string)GetValue(TextProperty); }
			set { SetValue(TextProperty, value); }
		}
		
		public bool IsEditable {
			get { return (bool)GetValue(IsEditableProperty); }
			set { SetValue(IsEditableProperty, value); }
		}
		
		static void TextChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
		{
			((AutoCompleteTextBox)d).editor.Text = (string)e.NewValue;
		}
		
		static void IsEditableChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
		{
			((AutoCompleteTextBox)d).editor.IsReadOnly = !(bool)e.NewValue;
		}
		
		public AutoCompleteTextBox()
		{
			object tmp;
			this.editorAdapter = EditorControlService.CreateEditor(out tmp);
			this.editor = (TextEditor)tmp;
			
			this.editor.Background = Brushes.Transparent;
			this.editor.ShowLineNumbers = false;
			this.editor.HorizontalScrollBarVisibility = ScrollBarVisibility.Hidden;
			this.editor.VerticalScrollBarVisibility = ScrollBarVisibility.Hidden;
			this.editor.TextArea.GotKeyboardFocus += delegate {
				this.Background = Brushes.White;
			};
			this.editor.TextArea.LostKeyboardFocus += delegate {
				this.Background = Brushes.Transparent;
				this.Text = this.editor.Text;
				this.editor.Select(0, 0);
			};
			this.editor.TextArea.PreviewKeyDown += editor_TextArea_PreviewKeyDown;
			this.editor.TextArea.TextEntered += editor_TextArea_TextEntered;
			
			this.Content = this.editor;
		}
		
		void editor_TextArea_PreviewKeyDown(object sender, KeyEventArgs e)
		{
			if (e.Key == Key.Return || e.Key == Key.Escape) {
				if (e.Key == Key.Return)
					this.Text = this.editor.Text;
				
				e.Handled = true;
			}
		}
		
		void editor_TextArea_TextEntered(object sender, TextCompositionEventArgs e)
		{
			StackFrame frame = WindowsDebugger.CurrentStackFrame;
			if (e.Text == "." && frame != null)
				ShowDotCompletion(frame, this.editor.Text);
		}
		
		private void ShowDotCompletion(StackFrame frame, string currentText)
		{
			string language = ProjectService.CurrentProject == null ? "C#" : ProjectService.CurrentProject.Language;
			NRefactoryResolver resolver = new NRefactoryResolver(LanguageProperties.GetLanguage(language));
			
			var seg = frame.NextStatement;
			
			var expressionFinder = ParserService.GetExpressionFinder(seg.Filename);
			var info = ParserService.GetParseInformation(seg.Filename);
			
			string text = ParserService.GetParseableFileContent(seg.Filename).Text;
			
			int currentOffset = this.editor.CaretOffset;
			
			var expr = expressionFinder.FindExpression(currentText, currentOffset);
			
			expr.Region = new DomRegion(seg.StartLine, seg.StartColumn, seg.EndLine, seg.EndColumn);
			
			var rr = resolver.Resolve(expr, info, text);
			
			if (rr != null) {
				editorAdapter.ShowCompletionWindow(new DotCodeCompletionItemProvider().GenerateCompletionListForResolveResult(rr, expr.Context));
			}
		}
	}
}