/*
 * CPResponder.j
 * AppKit
 *
 * Created by Francisco Tolmasky.
 * Copyright 2008, 280 North, Inc.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

@import <Foundation/CPObject.j>
@import <Foundation/CPObjJRuntime.j>

@import "CPEvent.j"

@class CPKeyBinding
@class CPMenu

CPDeleteKeyCode         = 8;
CPTabKeyCode            = 9;
CPReturnKeyCode         = 13;
CPEscapeKeyCode         = 27;
CPSpaceKeyCode          = 32;
CPPageUpKeyCode         = 33;
CPPageDownKeyCode       = 34;
CPLeftArrowKeyCode      = 37;
CPUpArrowKeyCode        = 38;
CPRightArrowKeyCode     = 39;
CPDownArrowKeyCode      = 40;
CPDeleteForwardKeyCode  = 46;

/*!
    @ingroup appkit
    @class CPResponder

    Subclasses of CPResonder can be part of the responder chain.
*/
@implementation CPResponder : CPObject
{
    CPMenu      _menu;
    CPResponder _nextResponder;
}

// Changing the first responder
/*!
    Returns \c YES if the receiver is able to become the first responder. \c NO otherwise.
*/
- (BOOL)acceptsFirstResponder
{
    return NO;
}

/*!
    Notifies the receiver that it will become the first responder. The receiver can reject first
    responder if it returns \c NO. The default implementation always returns \c YES.
    @return \c YES if the receiver accepts first responder status.
*/
- (BOOL)becomeFirstResponder
{
    return YES;
}

/*!
    Notifies the receiver that it has been asked to give up first responder status.
    @return \c YES if the receiver is willing to give up first responder status.
*/
- (BOOL)resignFirstResponder
{
    return YES;
}

// Setting the next responder
/*!
    Sets the receiver's next responder.
    @param aResponder the responder after the receiver
*/
- (void)setNextResponder:(CPResponder)aResponder
{
    _nextResponder = aResponder;
}

/*!
    Returns the responder after the receiver.
*/
- (CPResponder)nextResponder
{
    return _nextResponder;
}

/*!
    Called to interpret a series of key events.
    @param events an array of key CPEvents
*/
- (void)interpretKeyEvents:(CPArray)events
{
    var index = 0,
        count = [events count];

    for (; index < count; ++index)
    {
        var event = events[index],
            modifierFlags = [event modifierFlags],
            character = [event charactersIgnoringModifiers],
            selectorNames = [CPKeyBinding selectorsForKey:character modifierFlags:modifierFlags];

        if (selectorNames)
        {
            for (var s = 0, scount = selectorNames.length; s < scount; s++)
            {
                var selector = selectorNames[s];
                if (!selector)
                    continue;

                [self doCommandBySelector:CPSelectorFromString(selector)];
            }
        }
        else if (!(modifierFlags & (CPCommandKeyMask | CPControlKeyMask)) && [self respondsToSelector:@selector(insertText:)])
            [self insertText:[event characters]];
    }
}

/*!
    Notifies the receiver that the user has clicked the mouse down in its area.
    @param anEvent contains information about the click
*/
- (void)mouseDown:(CPEvent)anEvent
{
    [_nextResponder performSelector:_cmd withObject:anEvent];
}

/*!
    Notifies the receiver that the user has clicked the right mouse down in its area.
    @param anEvent contains information about the right click
*/
- (void)rightMouseDown:(CPEvent)anEvent
{
    [_nextResponder performSelector:_cmd withObject:anEvent];
}

/*!
    Notifies the receiver that the user has initiated a drag
    over it. A drag is a mouse movement while the left button is down.
    @param anEvent contains information about the drag
*/
- (void)mouseDragged:(CPEvent)anEvent
{
    [_nextResponder performSelector:_cmd withObject:anEvent];
}

/*!
    Notifies the receiver that the user has released the left mouse button.
    @param anEvent contains information about the release
*/
- (void)mouseUp:(CPEvent)anEvent
{
    [_nextResponder performSelector:_cmd withObject:anEvent];
}

/*!
    Notifies the receiver that the user has released the right mouse button.
    @param anEvent contains information about the release
*/
- (void)rightMouseUp:(CPEvent)anEvent
{
    [_nextResponder performSelector:_cmd withObject:anEvent];
}

/*!
    Notifies the receiver that the user has moved the mouse (with no buttons down).
    @param anEvent contains information about the movement
*/
- (void)mouseMoved:(CPEvent)anEvent
{
    [_nextResponder performSelector:_cmd withObject:anEvent];
}

- (void)mouseEntered:(CPEvent)anEvent
{
    [_nextResponder performSelector:_cmd withObject:anEvent];
}

/*!
    Notifies the receiver that the mouse exited the receiver's area.
    @param anEvent contains information about the exit
*/
- (void)mouseExited:(CPEvent)anEvent
{
    [_nextResponder performSelector:_cmd withObject:anEvent];
}

/*!
    Notifies the receiver that the mouse scroll wheel has moved.
    @param anEvent information about the scroll
*/
- (void)scrollWheel:(CPEvent)anEvent
{
    [_nextResponder performSelector:_cmd withObject:anEvent];
}

/*!
    Notifies the receiver that the user has pressed a key.
    @param anEvent information about the key press
*/
- (void)keyDown:(CPEvent)anEvent
{
    [_nextResponder performSelector:_cmd withObject:anEvent];
}

/*!
    Notifies the receiver that the user has released a key.
    @param anEvent information about the key press
*/
- (void)keyUp:(CPEvent)anEvent
{
    [_nextResponder performSelector:_cmd withObject:anEvent];
}

/*!
    Notifies the receiver that the user has pressed or released a modifier key (Shift, Control, and so on).
    @param anEvent information about the key press
*/
- (void)flagsChanged:(CPEvent)anEvent
{
    [_nextResponder performSelector:_cmd withObject:anEvent];
}

/*!
    Overridden by subclasses to handle a key equivalent.

    If the character code or codes in \c anEvent match the receiver’s key equivalent,
    the receiver should respond to the event and return \c YES. The default implementation
    does nothing and returns \c NO.

    You should extract the characters for a key equivalent using
    \ref CPEvent::charactersIgnoringModifiers "[anEvent charactersIgnoringModifiers]".

    @param anEvent An event object that represents the key equivalent pressed
    @return \c YES if theEvent is a key equivalent that the receiver handled, \c NO if it is not a key equivalent that it should handle.
*/
- (BOOL)performKeyEquivalent:(CPEvent)anEvent
{
    return NO;
}

// Action Methods
/*!
    Insert a line break at the caret position or selection.
    @param aSender the object requesting this
*/
- (void)insertLineBreak:(id)aSender
{
    [self insertNewline:aSender];
}

/*!
    Insert a line break at the caret position or selection.
    @param aSender the object requesting this
*/
- (void)insertNewline:(id)aSender
{
    [[self nextResponder] insertNewline:aSender];
}

- (void)insertTab:(id)sender
{
}

- (void)insertBackTab:(id)sender
{
}

/*!
    Inserts some text at the caret position or selection.
    @param aString the string to insert
*/
- (void)insertText:(CPString)aString
{
}

// Dispatch methods
/*!
    The receiver will attempt to perform the command,
    if it responds to it. If not, the \c -nextResponder will be called to do it.
    @param aSelector the command to attempt
*/
- (void)doCommandBySelector:(SEL)aSelector
{
    if ([self respondsToSelector:aSelector])
        [self performSelector:aSelector];
    else
        [_nextResponder doCommandBySelector:aSelector];
}

/*!
    The receiver will attempt to perform the command, or pass it on to the next responder if it doesn't respond to it.
    @param aSelector the command to perform
    @param anObject the argument to the method
    @return \c YES if the receiver was able to perform the command, or a responder down the chain was
    able to perform the command.
*/
- (BOOL)tryToPerform:(SEL)aSelector with:(id)anObject
{
    if ([self respondsToSelector:aSelector])
    {
        [self performSelector:aSelector withObject:anObject];

        return YES;
    }

    return [_nextResponder tryToPerform:aSelector with:anObject];
}

// Managing a Responder's menu

- (void)setMenu:(CPMenu)aMenu
{
    _menu = aMenu;
}

- (CPMenu)menu
{
    return _menu;
}

// Getting the Undo Manager
/*!
    Returns the undo manager for the receiver.
*/
- (CPUndoManager)undoManager
{
    return [_nextResponder performSelector:_cmd];
}

// Terminating the responder chain
/*!
    Called when an event finds no suitable responder.
    @param anEventSelector the command that failed
*/
- (void)noResponderFor:(SEL)anEventSelector
{
}

@end

var CPResponderNextResponderKey = @"CPResponderNextResponderKey",
    CPResponderMenuKey = @"CPResponderMenuKey";

@implementation CPResponder (CPCoding) <CPCoding>

/*!
    Initializes the responder with data from a coder.
    @param aCoder the coder from which data will be read
    @return the initialized responder
*/
- (id)initWithCoder:(CPCoder)aCoder
{
    self = [super init];

    if (self)
    {
        [self setNextResponder:[aCoder decodeObjectForKey:CPResponderNextResponderKey]];
        [self setMenu:[aCoder decodeObjectForKey:CPResponderMenuKey]];
    }

    return self;
}

/*!
    Archives the responder to a coder.
    @param aCoder the coder to which the responder will be archived
*/
- (void)encodeWithCoder:(CPCoder)aCoder
{
    // This will come out nil on the other side with decodeObjectForKey:
    if (_nextResponder !== nil)
        [aCoder encodeConditionalObject:_nextResponder forKey:CPResponderNextResponderKey];

    [aCoder encodeObject:_menu forKey:CPResponderMenuKey];
}

@end