/*  Part of XPCE --- The SWI-Prolog GUI toolkit

    Author:        Jan Wielemaker and Anjo Anjewierden
    E-mail:        jan@swi.psy.uva.nl
    WWW:           http://www.swi.psy.uva.nl/projects/xpce/
    Copyright (c)  1985-2002, University of Amsterdam
    All rights reserved.

    Redistribution and use in source and binary forms, with or without
    modification, are permitted provided that the following conditions
    are met:

    1. Redistributions of source code must retain the above copyright
       notice, this list of conditions and the following disclaimer.

    2. Redistributions in binary form must reproduce the above copyright
       notice, this list of conditions and the following disclaimer in
       the documentation and/or other materials provided with the
       distribution.

    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
    "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
    LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
    FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
    COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
    INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
    BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
    LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
    CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
    LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
    ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
    POSSIBILITY OF SUCH DAMAGE.
*/

#include <h/kernel.h>
#include <h/graphics.h>

static status
initialisePopupGesture(PopupGesture g, PopupObj popup,
		       Name button, Modifier modifier)
{ if ( isDefault(popup) )
    popup = NIL;

  initialiseGesture((Gesture) g, button, modifier);
  assign(g, popup, popup);

  succeed;
}


static status
cancelPopupGesture(PopupGesture g, EventObj ev)
{ assign(g, current, NIL);
  assign(g, context, NIL);

  return cancelGesture((Gesture)g, ev);
}


static status
updatePopupGesture(PopupGesture g, EventObj ev)
{ PopupObj p;
  Any rec = getMasterEvent(ev);

  DEBUG(NAME_popup, Cprintf("updatePopupGesture(): rec=%s\n", pp(rec)));

  if ( notNil(g->popup) )
  { if ( instanceOfObject(g->popup, ClassFunction) )
    { TRY( p = getForwardReceiverFunction((Function) g->popup, rec,
				  rec, ev, EAV) );
      TRY( p = checkType(p, nameToType(NAME_popup), g));
    } else
      p = g->popup;
  } else
  { if ( !(p = get(rec, NAME_popup, EAV)) ||
	 !instanceOfObject(p, ClassPopup) )
      fail;
  }

  assign(g, current, p);
  if ( isNil(g->context) )
    assign(g, context, notNil(p->context) ? p->context : rec);
  send(p, NAME_update, g->context, EAV);

  if ( p->active == OFF || emptyChain(p->members) )
  { send(g, NAME_cancel, ev, EAV);
    fail;
  }

  succeed;
}


static status
eventPopupGesture(PopupGesture g, EventObj ev)
{ if ( g->status == NAME_active && isUpEvent(ev) )
  { PceWindow sw;

    if ( !(sw = getWindowGraphical(ev->receiver)) )
      sw = ev->window;

    if ( notNil(g->current) && g->current->displayed == OFF )
    { send(g->current, NAME_open, ev->receiver,
	   getAreaPositionEvent(ev, DEFAULT), EAV);
      attributeObject(g, NAME_Stayup, ON);
      grabPointerWindow(sw, ON);
      focusWindow(sw, ev->receiver, (Recogniser) g, g->cursor, NIL);
    } else if ( valInt(getClickTimeEvent(ev)) < 400 &&
		getAttributeObject(g, NAME_Stayup) != ON )
    { attributeObject(g, NAME_Stayup, ON);
      grabPointerWindow(sw, ON);
      focusWindow(sw, ev->receiver, (Recogniser) g, g->cursor, NIL);
    } else
    { send(g, NAME_terminate, EAV);
      if ( isNil(g->current) )
      { grabPointerWindow(sw, OFF);
	focusWindow(sw, NIL, NIL, NIL, NIL);
	deleteAttributeObject(g, NAME_Stayup);
	assign(g, status, NAME_inactive);
      }
    }

    succeed;
  } else if ( notNil(g->current) && g->current->displayed == ON )
    return postEvent(ev, (Graphical) g->current, DEFAULT);

  if ( eventGesture(g, ev) )
    succeed;

  if ( g->status == NAME_active && isAEvent(ev, NAME_keyboard) )
  { Name key;

    TRY(updatePopupGesture(g, ev));
    key = characterName(getIdEvent(ev));

    if ( send(g->current, NAME_key, key, EAV) )
    { Any context = g->context;
      PopupObj current = g->current;

      assign(g, context, NIL);
      assign(g, current, NIL);

      send(current, NAME_execute, context, EAV);
      succeed;
    } else
      send(g, NAME_cancel, ev, EAV);
  }

  fail;
}


		/********************************
		*       GESTURE BEHAVIOUR	*
		********************************/

static status
verifyPopupGesture(PopupGesture g, EventObj ev)
{ return updatePopupGesture(g, ev);
}


static status
initiatePopupGesture(PopupGesture g, EventObj ev)
{ if ( isNil(g->max_drag_distance) )
  { send(g->current, NAME_open, ev->receiver,
	 getAreaPositionEvent(ev, DEFAULT), EAV);
    postEvent(ev, (Graphical) g->current, DEFAULT);
  }

  succeed;
}


static status
dragPopupGesture(PopupGesture g, EventObj ev)
{ if ( notNil(g->current) && g->current->displayed == ON )
  { DEBUG(NAME_popup, Cprintf("Posting drag to %s\n", pp(g->current)));
    return postEvent(ev, (Graphical) g->current, DEFAULT);
  } else
  { if ( notNil(g->max_drag_distance) )
    { PceWindow sw;

      if ( instanceOfObject((sw=ev->window), ClassWindow) &&
	   valInt(getDistanceEvent(sw->focus_event, ev)) >
	   valInt(g->max_drag_distance) )
	send(g, NAME_cancel, ev, EAV);
    }
  }

  fail;
}


/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
To avoid dangling references, the context and current are first copied
to local variables.
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */

static status
terminatePopupGesture(PopupGesture g, EventObj ev)
{ Any context = g->context;
  PopupObj current = g->current;

  if ( notNil(current) )
  { postEvent(ev, (Graphical) current, DEFAULT);

    if ( current->displayed == OFF )	/* for stayup */
    { PceWindow sw;

      if ( !(sw = getWindowGraphical(ev->receiver)) )
	sw = ev->window;

      assign(g, context, NIL);
      assign(g, current, NIL);

      grabPointerWindow(sw, OFF);
      send(current, NAME_execute, context, EAV);
      focusWindow(sw, NIL, NIL, NIL, NIL);
    }
  }

  succeed;
}


		 /*******************************
		 *	 CLASS DECLARATION	*
		 *******************************/

/* Type declarations */

static char *T_initialise[] =
        { "popup=[popup|function]", "button=[button_name]", "modifier=[modifier]" };

/* Instance Variables */

static vardecl var_popupGesture[] =
{ IV(NAME_popup, "popup|function*", IV_BOTH,
     NAME_popup, "Popup displayed"),
  IV(NAME_current, "popup*", IV_NONE,
     NAME_popup, "Currently visible popup"),
  IV(NAME_context, "any", IV_BOTH,
     NAME_context, "Context to be send with the ->execute"),
  IV(NAME_maxDragDistance, "int*", IV_BOTH,
     NAME_cancel, "Cancel after dragging this far")
};

/* Send Methods */

static senddecl send_popupGesture[] =
{ SM(NAME_drag, 1, "event", dragPopupGesture,
     DEFAULT, "Pass drag events to popup"),
  SM(NAME_initialise, 3, T_initialise, initialisePopupGesture,
     DEFAULT, "Create from popup, button and modifier"),
  SM(NAME_initiate, 1, "event", initiatePopupGesture,
     DEFAULT, "Show popup"),
  SM(NAME_terminate, 1, "event", terminatePopupGesture,
     DEFAULT, "Unshow popup and execute selected item"),
  SM(NAME_verify, 1, "event", verifyPopupGesture,
     DEFAULT, "Verify popup can be activated"),
  SM(NAME_cancel, 1, "event", cancelPopupGesture,
     NAME_cancel, "Cancel this gesture and try the next"),
  SM(NAME_event, 1, "event", eventPopupGesture,
     NAME_accelerator, "Handle accelerators")
};

/* Get Methods */

#define get_popupGesture NULL
/*
static getdecl get_popupGesture[] =
{
};
*/

/* Resources */

static classvardecl rc_popupGesture[] =
{ RC(NAME_button, "button_name", "right",
     "Active on which button (right)"),
  RC(NAME_cursor, "cursor", "arrow",
     "Cursor while active"),
  RC(NAME_modifier, "modifier", "",
     "Condition on shift, control and meta"),
  RC(NAME_maxDragDistance, "int*", "5",
     "Cancel after dragging this far")
};

/* Class Declaration */

static Name popupGesture_termnames[] = { NAME_popup, NAME_button, NAME_modifier };

ClassDecl(popupGesture_decls,
          var_popupGesture, send_popupGesture,
	  get_popupGesture, rc_popupGesture,
          3, popupGesture_termnames,
          "$Rev$");

status
makeClassPopupGesture(Class class)
{ return declareClass(class, &popupGesture_decls);
}



Recogniser
popupGesture()
{ if ( GESTURE_popup == NULL )
    GESTURE_popup = globalObject(NAME_PopupGesture, ClassPopupGesture, EAV);

  return (Recogniser) GESTURE_popup;
}
