//
// Copyright (C) 1996 Ben Ross
//
// You may distribute under the terms of the GNU General Public
// License as specified in the COPYING file.
//

// $Id: XeGCTable.C,v 1.1 1996/11/17 09:25:47 ben Exp $

#include <XeGCTable.h>
#include <XeApp.h>

#include <stdio.h>
#include <string.h>

#define TABLESIZE 256

XeGCTable::XeGCTable(void)
{
	_table = new TableElem*[TABLESIZE];
	for(int i=0; i < TABLESIZE; i++) {
		_table[i] = NULL;
	}
}

XeGCTable::~XeGCTable(void)
{
    TableElem **head;
    TableElem *temp;
    
    for(int i=0; i<TABLESIZE; i++) {
		head = &_table[i];
		while((temp = *head)) {
	    	*head = (*head)->_next;
	    	XFreeGC(gDisplay, temp->_gContext);
	    	delete temp;
		}
    }
    delete[] _table;
}


GC
XeGCTable::getGC(Window w, XGCValues* key, ulong flags)
{
	GC theGC;
	
	// This GC has already been cached, so return it.
	if((theGC = exists(key, flags))) {
//printf("Restoring GC 0x%08x from index: %d\n", theGC, hash(key, flags));
		return theGC;
	}
	
	theGC = XCreateGC(gDisplay, w, flags, key);
	addGC(theGC, key, flags);
	return theGC;
}

uchar
XeGCTable::charify(ulong val)
{
	uchar b1, b2, b3, b4;
    
    b1 = val & 0x000000ff;
    b2 = (val & 0x0000ff00) >> 8;
    b3 = (val & 0x00ff0000) >> 16;
    b4 = (val & 0xff000000) >> 24;
    
    return b1 ^ b2 ^ b3 ^ b4;
}

uchar
XeGCTable::hash(XGCValues* key, ulong flags)
{
	uchar index = 0;
	
	if(flags & GCFunction)
		index ^= charify(key->function);
	if(flags & GCForeground)
		index ^= charify(key->foreground);
	if(flags & GCBackground)
		index ^= charify(key->background);
	if(flags & GCLineWidth)
		index ^= charify((ulong)key->line_width);
	if(flags & GCFont)
		index ^= charify((ulong)key->font);
	
	return index;
}

void
XeGCTable::addGC(GC gc, XGCValues* key, ulong flags)
{
//printf("Adding GC 0x%08x at index: %d\n", gc, hash(key, flags));

	TableElem **head = &_table[hash(key, flags)];
    TableElem *elem = new TableElem;
    
    memcpy(&(elem->_key), key, sizeof(XGCValues));
    elem->_gContext = gc;
    elem->_prev = NULL;
    
    if(*head) {
		(*head)->_prev = elem;
    }
    elem->_next = *head;
    *head = elem;
}

GC
XeGCTable::exists(XGCValues* key, ulong flags)
{
    TableElem *temp = _table[hash(key, flags)];
    
    while(temp) {
    	if(compare(key, &(temp->_key), flags))
    		return temp->_gContext;
    	temp = temp->_next;
    }
    return NULL;
}

bool
XeGCTable::compare(XGCValues* k1, XGCValues* k2, ulong flags)
{
	if(!flags)
		return FALSE;
	if(flags & GCFunction && k1->function != k2->function)
		return FALSE;
	if(flags & GCPlaneMask && k1->plane_mask != k2->plane_mask)
		return FALSE;
	if(flags & GCForeground && k1->foreground != k2->foreground)
		return FALSE;
	if(flags & GCBackground && k1->background != k2->background)
		return FALSE;
	if(flags & GCLineWidth && k1->line_width != k2->line_width)
		return FALSE;
	if(flags & GCLineStyle && k1->line_style != k2->line_style)
		return FALSE;
	if(flags & GCCapStyle && k1->cap_style != k2->cap_style)
		return FALSE;
	if(flags & GCJoinStyle && k1->join_style != k2->join_style)
		return FALSE;
	if(flags & GCFillStyle && k1->fill_style != k2->fill_style)
		return FALSE;
	if(flags & GCFillRule && k1->fill_rule != k2->fill_rule)
		return FALSE;
	if(flags & GCArcMode && k1->arc_mode != k2->arc_mode)
		return FALSE;
	if(flags & GCTile && k1->tile != k2->tile)
		return FALSE;
	if(flags & GCStipple && k1->stipple != k2->stipple)
		return FALSE;
	if(flags & GCTileStipXOrigin && k1->ts_x_origin != k2->ts_x_origin)
		return FALSE;
	if(flags & GCTileStipYOrigin && k1->ts_y_origin != k2->ts_y_origin)
		return FALSE;
	if(flags & GCFont && k1->font != k2->font)
		return FALSE;
	if(flags & GCSubwindowMode && k1->subwindow_mode != k2->subwindow_mode)
		return FALSE;
	if(flags & GCGraphicsExposures && k1->graphics_exposures != k2->graphics_exposures)
		return FALSE;
	if(flags & GCClipXOrigin && k1->clip_x_origin != k2->clip_y_origin)
		return FALSE;
	if(flags & GCClipYOrigin && k1->clip_y_origin != k2->clip_y_origin)
		return FALSE;
	if(flags & GCClipMask && k1->clip_mask != k2->clip_mask)
		return FALSE;
	if(flags & GCDashOffset && k1->dash_offset != k2->dash_offset)
		return FALSE;
	if(flags & GCDashList && k1->dashes != k2->dashes)
		return FALSE;
	
	return TRUE;	
}