/*
 * TextForm.cs - Simple text viewer with search options.
 *
 * Copyright (C) 2004 - 2011 Andreas Scherrer
 *
 * This is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This software is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this software; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307,
 * USA.
 */

using System;
using System.Drawing;
using System.IO;
using System.Windows.Forms;

namespace Level9
{
	/// <summary>
	/// Simple text viewer with search options.
	/// </summary>
	public partial class TextForm : Form
	{
		// -- Attributes -----------------------------------------------------

		/// <summary>
		/// This property indicates whether the dialog disposes with the close
		/// operation.
		/// </summary>
		bool disposeOnClose = true;

		/// <summary>
		/// The Config.WindowSize instance that stores the dialog size.
		/// </summary>
		Config.WindowSize dialogSize = null;

		// -- Constructors ---------------------------------------------------

		/// <summary>
		/// Initializes a new instance of the TextForm class.
		/// </summary>
		/// <param name="disposeOnClose">
		/// if set to true the dialog disposes with the close operation
		/// </param>
		/// <param name="dialogSize">
		/// the Config.WindowSize instance that stores the dialog size
		/// </param>
		public TextForm(bool disposeOnClose, Config.WindowSize dialogSize)
		{
			InitializeComponent();

			this.disposeOnClose = disposeOnClose;
			this.dialogSize     = dialogSize;
			this.ClientSize     = dialogSize.ToSize();

			//
			// Set images
			//
			buttonNext.Image     = Images.Get(Images.Stock.Down_16x16);
			buttonPrevious.Image = Images.Get(Images.Stock.Up_16x16);
			menuItemCopy.Image   = Images.Get(Images.Stock.Copy_16x16);
			menuItemSave.Image   = Images.Get(Images.Stock.Save_16x16);
			menuItemClose.Image  = Images.Get(Images.Stock.Close_16x16);
		}

		// -- Event handling -------------------------------------------------

		/// <summary>
		/// Invoked when the form is being closed.
		/// </summary>
		/// <param name="sender">the object that originated the event</param>
		/// <param name="e">
		/// a FormClosingEventArgs that contains the event data
		/// </param>
		void TextFormFormClosing(object sender, FormClosingEventArgs e)
		{
			if (this.WindowState == FormWindowState.Normal) {
				dialogSize.FromSize(this.ClientSize);
			}

			if (!disposeOnClose && e.CloseReason == CloseReason.UserClosing) {
				e.Cancel = true;
				this.DialogResult = DialogResult.OK;
				this.Hide();
			}
			else {
				e.Cancel = false;
			}
		}

		/// <summary>
		/// Invoked when the 'Close' menu item has been clicked.
		/// </summary>
		/// <param name="sender">the object that originated the event</param>
		/// <param name="e">an EventArgs that contains the event data</param>
		void MenuItemCloseClick(object sender, EventArgs e)
		{
			this.DialogResult = DialogResult.OK;
			this.Close();
		}

		/// <summary>
		/// Invoked when the 'Copy to clipboard' menu item has been clicked.
		/// </summary>
		/// <param name="sender">the object that originated the event</param>
		/// <param name="e">an EventArgs that contains the event data</param>
		void MenuItemCopyClick(object sender, EventArgs e)
		{
			textBox.SuspendLayout();
			textBox.SelectAll();
			textBox.Copy();
			textBox.SelectionLength = 0;
			textBox.ResumeLayout(true);
		}

		/// <summary>
		/// Invoked when the 'Save' menu item has been clicked.
		/// </summary>
		/// <param name="sender">the object that originated the event</param>
		/// <param name="e">an EventArgs that contains the event data</param>
		void MenuItemSaveClick(object sender, EventArgs e)
		{
			string filename = FileUtils.SFDTextFiles(menuItemSave.Text);

			if (filename != null) {
				try {
					FileStream fs = new FileStream(filename,
						FileMode.Create);
					StreamWriter writer = new StreamWriter(fs);
					writer.Write(textBox.Text);
					writer.Close();
					fs.Close();
				}
				catch (Exception ex) {
					ErrorHandler.Handle(this,
						"Error writing output file.", ex);
				}
			}
		}

		/// <summary>
		/// Invoked when the 'Find next' button has been pressed.
		/// </summary>
		/// <param name="sender">the object that originated the event</param>
		/// <param name="e">an EventArgs that contains the event data</param>
		void ButtonNextClick(object sender, EventArgs e)
		{
			FindText(false);
		}

		/// <summary>
		/// Invoked when the 'Find previous' button has been pressed.
		/// </summary>
		/// <param name="sender">the object that originated the event</param>
		/// <param name="e">an EventArgs that contains the event data</param>
		void ButtonPreviousClick(object sender, EventArgs e)
		{
			FindText(true);
		}

		/// <summary>
		/// Invoked when the form has focus and the user presses a key.
		/// </summary>
		/// <param name="sender">the object that originated the event</param>
		/// <param name="e">an EventArgs that contains the event data</param>
		void TextFormKeyDown(object sender, KeyEventArgs e)
		{
			switch (e.KeyCode) {
				case Keys.Return:
					if (textBoxFind.Focused) {
						ButtonNextClick(sender, e);
					}
					break;
				case Keys.F3:
					if (e.Modifiers == Keys.Shift) {
						ButtonPreviousClick(sender, e);
					}
					else {
						ButtonNextClick(sender, e);
					}
					break;
				default:
					break;
			}
		}

		/// <summary>
		/// Invoked when the text in the 'Find' text box has been changed.
		/// </summary>
		/// <param name="sender">the object that originated the event</param>
		/// <param name="e">an EventArgs that contains the event data</param>
		void TextBoxFindTextChanged(object sender, EventArgs e)
		{
			textBoxFind.BackColor = SystemColors.HighlightText;
		}

		// -- Methods --------------------------------------------------------

		/// <summary>
		/// Searches for a search term in the text associated with this control.
		/// </summary>
		/// <param name="previous">
		/// if set to true the search looks for previous occurrences of the
		/// search term
		/// </param>
		/// <returns>
		/// true if the search term has been found, else false
		/// </returns>
		bool FindText(bool previous)
		{
			bool found = false;

			if (textBoxFind.TextLength > 1) {

				int index, startIndex, endIndex;
				RichTextBoxFinds finds = RichTextBoxFinds.None;

				textBoxFind.BackColor = SystemColors.HighlightText;

				if (previous) {
					finds     |= RichTextBoxFinds.Reverse;
					startIndex = 0;
					endIndex   = textBox.SelectionStart;
				}
				else {
					startIndex = textBox.SelectionStart
						+ textBox.SelectionLength;
					textBox.SelectionLength = 0;
					textBox.SelectionStart  = startIndex;
					endIndex = textBox.TextLength;
				}

				index = textBox.Find(textBoxFind.Text, startIndex,
					endIndex, finds);
				if (index < 0) {
					index = textBox.Find(textBoxFind.Text, 0,
						textBox.TextLength, finds);
				}
				if (index > 0) {
					found = true;
					textBox.Focus();
				}
				else {
					textBoxFind.BackColor = Color.Pink;
					textBoxFind.SelectionLength = 0;
				}
			}

			return found;
		}

		/// <summary>
		/// Appends a string to the text associated with this control.
		/// </summary>
		/// <param name="text">the text to append</param>
		public void AppendText(string text)
		{
			if (text == null || text.Length == 0) {
				return;
			}
			textBox.AppendText(text);
		}

		/// <summary>
		/// Appends a string to the text associated with this control.
		/// </summary>
		/// <param name="text">the text to append</param>
		/// <param name="color">the text color</param>
		public void AppendText(string text, Color color)
		{
			if (text == null || text.Length == 0) {
				return;
			}
			textBox.AppendText(text);
			textBox.SelectionStart  = textBox.TextLength - text.Length;
			textBox.SelectionLength = text.Length;
			textBox.SelectionColor  = color;
			textBox.SelectionLength = 0;
		}

		/// <summary>
		/// Sets the caret position.
		/// </summary>
		/// <param name="pos">the caret position</param>
		public void SetCaretPosition(int pos)
		{
			if (pos >= 0 && pos < textBox.TextLength) {
				textBox.SelectionStart = pos;
				textBox.SelectionLength = 0;
			}
		}

		/// <summary>
		/// Returns the length of the text associated with this control.
		/// </summary>
		public int GetTextLength()
		{
			return textBox.TextLength;
		}

		/// <summary>
		/// Clears the text associated with this control.
		/// </summary>
		public void Clear()
		{
			textBox.SelectionStart = 0;
			textBox.Clear();
		}
	}
}