#region Copyright & License Information
/*
 * Copyright 2007-2010 The OpenRA Developers (see AUTHORS)
 * This file is part of OpenRA, which is free software. It is made 
 * available to you under the terms of the GNU General Public License
 * as published by the Free Software Foundation. For more information,
 * see LICENSE.
 */
#endregion

using System;
using System.Drawing;

namespace OpenRA.Widgets
{
	class TextFieldWidget : Widget
	{
		public string Text = "";
		public int MaxLength = 0;
		public bool Bold = false;
		public int VisualHeight = 1;
		public Func<bool> OnEnterKey = () => false;
		public Func<bool> OnTabKey = () => false;
		public Action OnLoseFocus = () => { };

		public TextFieldWidget()
			: base()
		{
		}

		protected TextFieldWidget(TextFieldWidget widget)
			: base(widget)
		{
			Text = widget.Text;
			MaxLength = widget.MaxLength;
			Bold = widget.Bold;
			VisualHeight = widget.VisualHeight;
		}

		public override bool LoseFocus(MouseInput mi)
		{
			OnLoseFocus();
			var lose = base.LoseFocus(mi);
			return lose;
		}

		public override bool HandleInputInner(MouseInput mi)
		{
			if (mi.Event == MouseInputEvent.Move)
				return false;

			// Lose focus if they click outside the box; return false so the next widget can grab this event
			if (mi.Event == MouseInputEvent.Down && !RenderBounds.Contains(mi.Location.X, mi.Location.Y) && LoseFocus(mi))
				return false;

			if (mi.Event == MouseInputEvent.Down && !TakeFocus(mi))
				return false;

			blinkCycle = 10;
			showCursor = true;
			return true;
		}

		public override bool HandleKeyPressInner(KeyInput e)
		{
			if (e.Event == KeyInputEvent.Up) return false;
			
			// Only take input if we are focused
			if (!Focused)
				return false;

			if (e.KeyChar == '\r' && OnEnterKey())
				return true;

			if (e.KeyChar == '\t' && OnTabKey())
				return true;

			TypeChar(e.KeyChar);
			return true;
		}

		public void TypeChar(char c)
		{
			if (c == '\b' || c == 0x7f)
			{
				if (Text.Length > 0)
					Text = Text.Remove(Text.Length - 1);
			}
			else if (!char.IsControl(c))
			{
				if (MaxLength > 0 && Text.Length >= MaxLength)
					return;

				Text += c;
			}
		}

		int blinkCycle = 10;
		bool showCursor = true;
		public override void Tick(World world)
		{
			if (--blinkCycle <= 0)
			{
				blinkCycle = 20;
				showCursor ^= true;
			}
			base.Tick(world);
		}

		public override void DrawInner()
		{
			int margin = 5;
			var font = (Bold) ? Game.Renderer.BoldFont : Game.Renderer.RegularFont;
			var cursor = (showCursor && Focused) ? "|" : "";
			var textSize = font.Measure(Text + "|");
			var pos = RenderOrigin;

			WidgetUtils.DrawPanel("dialog3",
				new Rectangle(pos.X, pos.Y, Bounds.Width, Bounds.Height));

			// Inset text by the margin and center vertically
			var textPos = pos + new int2(margin, (Bounds.Height - textSize.Y) / 2 - VisualHeight);

			// Right align when editing and scissor when the text overflows
			if (textSize.X > Bounds.Width - 2 * margin)
			{
				if (Focused)
					textPos += new int2(Bounds.Width - 2 * margin - textSize.X, 0);

				Game.Renderer.EnableScissor(pos.X + margin, pos.Y, Bounds.Width - 2 * margin, Bounds.Bottom);
			}

			font.DrawText(Text + cursor, textPos, Color.White);

			if (textSize.X > Bounds.Width - 2 * margin)
				Game.Renderer.DisableScissor();
		}

		public override Widget Clone() { return new TextFieldWidget(this); }
	}
}