// 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.Globalization;
using ICSharpCode.AvalonEdit.Document;

namespace ICSharpCode.AvalonEdit
{
	/// <summary>
	/// Represents a text location with a visual column.
	/// </summary>
	public struct TextViewPosition : IEquatable<TextViewPosition>
	{
		int line, column, visualColumn;
		
		/// <summary>
		/// Gets/Sets the line number.
		/// </summary>
		public int Line {
			get { return line; }
			set { line = value; }
		}
		
		/// <summary>
		/// Gets/Sets the (text) column number.
		/// </summary>
		public int Column {
			get { return column; }
			set { column = value; }
		}
		
		/// <summary>
		/// Gets/Sets the visual column number.
		/// Can be -1 (meaning unknown visual column).
		/// </summary>
		public int VisualColumn {
			get { return visualColumn; }
			set { visualColumn = value; }
		}
		
		/// <summary>
		/// Creates a new TextViewPosition instance.
		/// </summary>
		public TextViewPosition(int line, int column, int visualColumn)
		{
			this.line = line;
			this.column = column;
			this.visualColumn = visualColumn;
		}
		
		/// <summary>
		/// Creates a new TextViewPosition instance.
		/// </summary>
		public TextViewPosition(int line, int column)
			: this(line, column, -1)
		{
		}
		
		/// <summary>
		/// Creates a new TextViewPosition instance.
		/// </summary>
		public TextViewPosition(TextLocation location, int visualColumn)
		{
			this.line = location.Line;
			this.column = location.Column;
			this.visualColumn = visualColumn;
		}
		
		/// <summary>
		/// Creates a new TextViewPosition instance.
		/// </summary>
		public TextViewPosition(TextLocation location)
			: this(location, -1)
		{
		}
		
		/// <inheritdoc/>
		public override string ToString()
		{
			return string.Format(CultureInfo.InvariantCulture,
			                     "[TextViewPosition Line={0} Column={1} VisualColumn={2}]",
			                     this.line, this.column, this.visualColumn);
		}
		
		/// <summary>
		/// Implicit conversion to <see cref="TextLocation"/>.
		/// </summary>
		public static implicit operator TextLocation(TextViewPosition position)
		{
			return new TextLocation(position.Line, position.Column);
		}
		
		#region Equals and GetHashCode implementation
		// The code in this region is useful if you want to use this structure in collections.
		// If you don't need it, you can just remove the region and the ": IEquatable<Struct1>" declaration.
		
		/// <inheritdoc/>
		public override bool Equals(object obj)
		{
			if (obj is TextViewPosition)
				return Equals((TextViewPosition)obj); // use Equals method below
			else
				return false;
		}
		
		/// <inheritdoc/>
		public override int GetHashCode()
		{
			int hashCode = 0;
			unchecked {
				hashCode += 1000000007 * Line.GetHashCode();
				hashCode += 1000000009 * Column.GetHashCode();
				hashCode += 1000000021 * VisualColumn.GetHashCode();
			}
			return hashCode;
		}
		
		/// <summary>
		/// Equality test.
		/// </summary>
		public bool Equals(TextViewPosition other)
		{
			return this.Line == other.Line && this.Column == other.Column && this.VisualColumn == other.VisualColumn;
		}
		
		/// <summary>
		/// Equality test.
		/// </summary>
		public static bool operator ==(TextViewPosition left, TextViewPosition right)
		{
			return left.Equals(right);
		}
		
		/// <summary>
		/// Inequality test.
		/// </summary>
		public static bool operator !=(TextViewPosition left, TextViewPosition right)
		{
			return !(left.Equals(right)); // use operator == and negate result
		}
		#endregion
	}
}