/*
 * InputHandler.java - Manages key bindings and executes actions
 * :tabSize=8:indentSize=8:noTabs=false:
 * :folding=explicit:collapseFolds=1:
 *
 * Copyright (C) 1999, 2003 Slava Pestov
 *
 * This program 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 any later version.
 *
 * This program 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 program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 */

package org.gjt.sp.jedit.gui;

//{{{ Imports
import javax.swing.*;
import javax.swing.text.JTextComponent;

import org.gjt.sp.jedit.textarea.JEditTextArea;
import org.gjt.sp.jedit.*;
import org.gjt.sp.jedit.buffer.JEditBuffer;
import org.gjt.sp.jedit.input.AbstractInputHandler;
import org.gjt.sp.util.Log;

import java.awt.event.KeyEvent;
import java.awt.*;
//}}}

/**
 * An input handler converts the user's key strokes into concrete actions.
 * It also takes care of macro recording and action repetition.<p>
 *
 * This class provides all the necessary support code for an input
 * handler, but doesn't actually do any key binding logic. It is up
 * to the implementations of this class to do so.
 *
 * @author Slava Pestov
 * @version $Id: InputHandler.java 8244 2006-12-19 08:06:03Z kpouer $
 * @see org.gjt.sp.jedit.gui.DefaultInputHandler
 */
public abstract class InputHandler extends AbstractInputHandler
{
	//{{{ InputHandler constructor
	/**
	 * Creates a new input handler.
	 * @param view The view
	 */
	public InputHandler(View view)
	{
		super();
		this.view = view;
	} //}}}

	//{{{ addKeyBinding() method
	/**
	 * Adds a key binding to this input handler.
	 * @param keyBinding The key binding (the format of this is
	 * input-handler specific)
	 * @param action The action
	 */
	public abstract void addKeyBinding(String keyBinding, String action);
	//}}}

	//{{{ addKeyBinding() method
	/**
	 * Adds a key binding to this input handler.
	 * @param keyBinding The key binding (the format of this is
	 * input-handler specific)
	 * @param action The action
	 */
	public abstract void addKeyBinding(String keyBinding, EditAction action);
	//}}}

	//{{{ removeKeyBinding() method
	/**
	 * Removes a key binding from this input handler.
	 * @param keyBinding The key binding
	 */
	public abstract void removeKeyBinding(String keyBinding);
	//}}}

	//{{{ removeAllKeyBindings() method
	/**
	 * Removes all key bindings from this input handler.
	 */
	public abstract void removeAllKeyBindings();
	//}}}

	/**
 	 * Handles a keystroke.
	 * @param keyStroke The key stroke.
	 * @return true if the input could be handled.
	 * @since jEdit 4.2pre5
	 */
	public final boolean handleKey(KeyEventTranslator.Key keyStroke)
	{
		return handleKey(keyStroke, false);
	}

	/**
	 * Forwards key events directly to the input handler.
	 * This is slightly faster than using a KeyListener
	 * because some Swing overhead is avoided.
	 * @since 4.3pre7
	 */
	public void processKeyEvent(KeyEvent evt, int from, boolean global)
	{
		if(Debug.DUMP_KEY_EVENTS)
		{
			Log.log(Log.DEBUG,this,"Key event                 : "
				+ GrabKeyDialog.toString(evt) + " from " + from);
			Log.log(Log.DEBUG,this,view+".isFocused()="+view.isFocused()+'.',new Exception());
		}

		if(view.getTextArea().hasFocus() && from == View.VIEW)
			return;

		evt = _preprocessKeyEvent(evt);
		if(evt == null)
			return;

		if(Debug.DUMP_KEY_EVENTS)
		{
			Log.log(Log.DEBUG,this,"Key event after workaround: "
				+ GrabKeyDialog.toString(evt) + " from " + from);
		}

		Component prefixFocusOwner = view.getPrefixFocusOwner();
		boolean focusOnTextArea = false;
		switch(evt.getID())
		{
		case KeyEvent.KEY_TYPED:
			// if the user pressed eg C+e n n in the
			// search bar we want focus to go back there
			// after the prefix is done
			if(prefixFocusOwner != null)
			{
				if(prefixFocusOwner.isShowing())
				{
					prefixFocusOwner.requestFocus();
					focusOnTextArea = true;
				}
			}

			if(keyEventInterceptor != null)
				keyEventInterceptor.keyTyped(evt);
			else if(from == View.ACTION_BAR
				|| (Debug.GLOBAL_SHORTCUTS_FOR_DOCKED_DOCKABLES &&
				    Options.SIMPLIFIED_KEY_HANDLING)
				|| isPrefixActive()
				|| view.getTextArea().hasFocus())
			{
				processKeyEventKeyStrokeHandling(evt,from,"type ",global);
			}


			processKeyEventSub(focusOnTextArea);

			break;
		case KeyEvent.KEY_PRESSED:
			if(keyEventInterceptor != null)
				keyEventInterceptor.keyPressed(evt);
			else if(KeyEventWorkaround.isBindable(evt.getKeyCode()))
			{
				if(prefixFocusOwner != null)
				{
					if(prefixFocusOwner.isShowing())
					{
						prefixFocusOwner.requestFocus();
						focusOnTextArea = true;
					}
					view.setPrefixFocusOwner(null);
				}

				processKeyEventKeyStrokeHandling(evt,from,"press",global);

				processKeyEventSub(focusOnTextArea);

			}
			break;
		case KeyEvent.KEY_RELEASED:
			if(keyEventInterceptor != null)
				keyEventInterceptor.keyReleased(evt);
			break;
		}
	} //}}}
	
	//{{{ _preprocessKeyEvent() method
	private KeyEvent _preprocessKeyEvent(KeyEvent evt)
	{
		if(view.isClosed())
			return null;
		Component focusOwner = view.getFocusOwner();
		if (Options.SIMPLIFIED_KEY_HANDLING)
		{
			/*
				It seems that the "else" path below does
				not work. Apparently, is is there to prevent
				some keyboard events to be "swallowed" by
				jEdit when the keyboard event in fact should
				be scheduled to swing for further handling.

				On some "key typed" events, the "return null;"
				is triggered. However, these key events
				actually do not seem to be handled elseewhere,
				so they are not handled at all.

				This behaviour exists with old keyboard handling
				as well as with new keyboard handling. However,
				the new keyboard handling is more sensitive
				about what kinds of key events it receives. It
				expects to see all "key typed" events,
				which is incompatible with the "return null;"
				below.

				This bug triggers jEdit bug 1493185 ( https://sourceforge.net/tracker/?func=detail&aid=1493185&group_id=588&atid=100588 ).

				Thus, we disable the possibility of
				key event swallowing for the new key event
				handling.

			*/
		}
		else
		{
			if(focusOwner instanceof JComponent)
			{
				JComponent comp = (JComponent)focusOwner;
				InputMap map = comp.getInputMap();
				ActionMap am = comp.getActionMap();

				if(map != null && am != null && comp.isEnabled())
				{
					KeyStroke	keyStroke	= KeyStroke.getKeyStrokeForEvent(evt);
					Object binding = map.get(keyStroke);
					if(binding != null && am.get(binding) != null)
					{
						return null;
					}
				}
			}
		}

		if(focusOwner instanceof JTextComponent)
		{
			// fix for the bug where key events in JTextComponents
			// inside views are also handled by the input handler
			if(evt.getID() == KeyEvent.KEY_PRESSED)
			{
				switch(evt.getKeyCode())
				{
				case KeyEvent.VK_ENTER:
				case KeyEvent.VK_TAB:
				case KeyEvent.VK_BACK_SPACE:
				case KeyEvent.VK_SPACE:
					return null;
				}
			}
		}

		if(evt.isConsumed())
			return null;

		if(Debug.DUMP_KEY_EVENTS)
		{
			Log.log(Log.DEBUG,this,"Key event (preprocessing) : "
					+ GrabKeyDialog.toString(evt));
		}

		return KeyEventWorkaround.processKeyEvent(evt);
	} //}}}

	//{{{ processKeyEventSub() method
	private void processKeyEventSub(boolean focusOnTextArea)
	{
		// we might have been closed as a result of
		// the above
		if(view.isClosed())
			return;

		// this is a weird hack.
		// we don't want C+e a to insert 'a' in the
		// search bar if the search bar has focus...
		if(isPrefixActive())
		{
			Component focusOwner = view.getFocusOwner();
			if(focusOwner instanceof JTextComponent)
			{
				view.setPrefixFocusOwner(focusOwner);
				view.getTextArea().requestFocus();
			}
			else if(focusOnTextArea)
			{
				view.getTextArea().requestFocus();
			}
			else
			{
				view.setPrefixFocusOwner(null);
			}
		}
		else
		{
			view.setPrefixFocusOwner(null);
		}
	}
	//}}}

	//{{{ getRepeatCount() method
	/**
	 * Returns the number of times the next action will be repeated.
	 */
	public int getRepeatCount()
	{
		return repeatCount;
	} //}}}

	//{{{ setRepeatCount() method
	/**
	 * Sets the number of times the next action will be repeated.
	 * @param repeatCount The repeat count
	 */
	public void setRepeatCount(int repeatCount)
	{
		int oldRepeatCount = this.repeatCount;
		this.repeatCount = repeatCount;
		if(oldRepeatCount != repeatCount)
			view.getStatus().setMessage(null);
	} //}}}

	//{{{ getLastAction() method
	/**
	 * Returns the last executed action.
	 * @since jEdit 2.5pre5
	 */
	public EditAction getLastAction()
	{
		return lastAction;
	} //}}}

	//{{{ readNextChar() method
	/**
	 * Invokes the specified BeanShell code, replacing __char__ in the
	 * code with the next input character.
	 * @param msg The prompt to display in the status bar
	 * @param code The code
	 * @since jEdit 3.2pre2
	 */
	public void readNextChar(String msg, String code)
	{
		view.getStatus().setMessage(msg);
		readNextChar = code;
	} //}}}

	//{{{ readNextChar() method
	/**
	 * @deprecated Use the other form of this method instead
	 */
	public void readNextChar(String code)
	{
		readNextChar = code;
	} //}}}

	//{{{ invokeAction() method
	/**
	 * Invokes the specified action, repeating and recording it as
	 * necessary.
	 * @param action The action
	 * @since jEdit 4.2pre1
	 */
	public void invokeAction(String action)
	{
		invokeAction(jEdit.getAction(action));
	} //}}}

	//{{{ invokeAction() method
	/**
	 * Invokes the specified action, repeating and recording it as
	 * necessary.
	 * @param action The action
	 */
	public void invokeAction(EditAction action)
	{
		JEditBuffer buffer = view.getBuffer();

		/* if(buffer.insideCompoundEdit())
			buffer.endCompoundEdit(); */

		// remember the last executed action
		if(!action.noRememberLast())
		{
			HistoryModel.getModel("action").addItem(action.getName());
			if(lastAction == action)
				lastActionCount++;
			else
			{
				lastAction = action;
				lastActionCount = 1;
			}
		}

		// remember old values, in case action changes them
		int _repeatCount = repeatCount;

		// execute the action
		if(action.noRepeat() || _repeatCount == 1)
			action.invoke(view);
		else
		{
			// stop people doing dumb stuff like C+ENTER 100 C+n
			if(_repeatCount > REPEAT_COUNT_THRESHOLD)
			{
				String label = action.getLabel();
				if(label == null)
					label = action.getName();
				else
					label = GUIUtilities.prettifyMenuLabel(label);

				Object[] pp = { label, _repeatCount };

				if(GUIUtilities.confirm(view,"large-repeat-count",pp,
					JOptionPane.WARNING_MESSAGE,
					JOptionPane.YES_NO_OPTION)
					!= JOptionPane.YES_OPTION)
				{
					repeatCount = 1;
					view.getStatus().setMessage(null);
					return;
				}
			}

			try
			{
				buffer.beginCompoundEdit();

				for(int i = 0; i < _repeatCount; i++)
					action.invoke(view);
			}
			finally
			{
				buffer.endCompoundEdit();
			}
		}

		Macros.Recorder recorder = view.getMacroRecorder();

		if(recorder != null && !action.noRecord())
			recorder.record(_repeatCount,action.getCode());

		// If repeat was true originally, clear it
		// Otherwise it might have been set by the action, etc
		if(_repeatCount != 1)
		{
			// first of all, if this action set a
			// readNextChar, do not clear the repeat
			if(readNextChar != null)
				return;

			repeatCount = 1;
			view.getStatus().setMessage(null);
		}
	} //}}}

	//{{{ invokeLastAction() method
	public void invokeLastAction()
	{
		if(lastAction == null)
			view.getToolkit().beep();
		else
			invokeAction(lastAction);
	} //}}}


	//{{{ Instance variables
	protected View view;

	protected EditAction lastAction;

	//}}}

	//{{{ userInput() method
	protected void userInput(char ch)
	{
		lastActionCount = 0;

		JEditTextArea textArea = view.getTextArea();

		/* Buffer buffer = view.getBuffer();
		if(!buffer.insideCompoundEdit())
			buffer.beginCompoundEdit(); */

		if(repeatCount == 1)
			textArea.userInput(ch);
		else
		{
			// stop people doing dumb stuff like C+ENTER 100 C+n
			if(repeatCount > REPEAT_COUNT_THRESHOLD)
			{
				Object[] pp = { String.valueOf(ch),
					repeatCount };

				if(GUIUtilities.confirm(view,
					"large-repeat-count.user-input",pp,
					JOptionPane.WARNING_MESSAGE,
					JOptionPane.YES_NO_OPTION)
					!= JOptionPane.YES_OPTION)
				{
					repeatCount = 1;
					view.getStatus().setMessage(null);
					return;
				}
			}

			JEditBuffer buffer = view.getBuffer();
			try
			{
				if(repeatCount != 1)
					buffer.beginCompoundEdit();
				for(int i = 0; i < repeatCount; i++)
					textArea.userInput(ch);
			}
			finally
			{
				if(repeatCount != 1)
					buffer.endCompoundEdit();
			}
		}

		Macros.Recorder recorder = view.getMacroRecorder();

		if(recorder != null)
		{
			recorder.recordInput(repeatCount,ch,
				textArea.isOverwriteEnabled());
		}

		repeatCount = 1;
	} //}}}

	//{{{ invokeReadNextChar() method
	protected void invokeReadNextChar(char ch)
	{
		JEditBuffer buffer = view.getBuffer();

		/* if(buffer.insideCompoundEdit())
			buffer.endCompoundEdit(); */

		String charStr = MiscUtilities.charsToEscapes(String.valueOf(ch));

		// this might be a bit slow if __char__ occurs a lot
		int index;
		while((index = readNextChar.indexOf("__char__")) != -1)
		{
			readNextChar = readNextChar.substring(0,index)
				+ '\'' + charStr + '\''
				+ readNextChar.substring(index + 8);
		}

		Macros.Recorder recorder = view.getMacroRecorder();
		if(recorder != null)
			recorder.record(getRepeatCount(),readNextChar);

		view.getStatus().setMessage(null);

		if(getRepeatCount() != 1)
		{
			try
			{
				buffer.beginCompoundEdit();

				BeanShell.eval(view,BeanShell.getNameSpace(),
					"for(int i = 1; i < "
					+ getRepeatCount() + "; i++)\n{\n"
					+ readNextChar + "\n}");
			}
			finally
			{
				buffer.endCompoundEdit();
			}
		}
		else
			BeanShell.eval(view,BeanShell.getNameSpace(),readNextChar);

		readNextChar = null;
	} //}}}

	//}}}
}