/*
 * Copyright (c) 1999 R.B. Kissh & Associates
 * Copyright (c) 1987, 1988, 1989, 1990, 1991 Stanford University
 * Copyright (c) 1991 Silicon Graphics, Inc.
 *
 * Permission to use, copy, modify, distribute, and sell this software and 
 * its documentation for any purpose is hereby granted without fee, provided
 * that (i) the above copyright notices and this permission notice appear in
 * all copies of the software and related documentation, and (ii) the names of
 * Stanford and Silicon Graphics may not be used in any advertising or
 * publicity relating to the software without the specific, prior written
 * permission of Stanford and Silicon Graphics.
 * 
 * THE SOFTWARE IS PROVIDED "AS-IS" AND WITHOUT WARRANTY OF ANY KIND, 
 * EXPRESS, IMPLIED OR OTHERWISE, INCLUDING WITHOUT LIMITATION, ANY 
 * WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.  
 *
 * IN NO EVENT SHALL STANFORD OR SILICON GRAPHICS BE LIABLE FOR
 * ANY SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY KIND,
 * OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
 * WHETHER OR NOT ADVISED OF THE POSSIBILITY OF DAMAGE, AND ON ANY THEORY OF 
 * LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE 
 * OF THIS SOFTWARE.
 */

/*
 * X11-dependent raster code
 */

#include <InterViews/canvas.h>
#include <InterViews/display.h>
#include <InterViews/raster.h>
#include <InterViews/session.h>
#include <IV-X11/Xlib.h>
#include <IV-X11/Xutil.h>
#include <IV-X11/xdisplay.h>
#include <IV-X11/xraster.h>

#include <stream.h>

#ifdef XSHM
#include <stream.h>
#include <sys/ipc.h>
#include <sys/shm.h>
#include <IV-X11/Xdefs.h>
#include <X11/extensions/XShm.h>
#include <IV-X11/Xundefs.h>

// no X prototype
extern "C" int XShmGetEventBase(XDisplay*);

static boolean xerror_alert;

static int XError(XDisplay*, XErrorEvent*) {
  xerror_alert = true;
  return true;
}
#endif

Raster::Raster(unsigned long w, unsigned long h) {
    RasterRep* r = new RasterRep;
    rep_ = r;
    Display* d = Session::instance()->default_display();
    r->display_ = d;
    r->modified_ = false;
    r->pwidth_ = (unsigned int)w;
    r->pheight_ = (unsigned int)h;
    r->width_ = d->to_coord(r->pwidth_);
    r->height_ = d->to_coord(r->pheight_);
    r->left_ = 0;
    r->bottom_ = 0;
    r->right_ = r->width_;
    r->top_ = r->height_;
    r->shared_memory_ = false;

    DisplayRep* dr = r->display_->rep();
    XDisplay* dpy = dr->display_;
    r->pixmap_ = XCreatePixmap(
	dpy, dr->root_, r->pwidth_, r->pheight_, dr->default_visual_->depth()
    );
    r->gc_ = XCreateGC(dpy, r->pixmap_, 0, nil);

#ifdef XSHM
    init_shared_memory();
#endif

    if (!r->shared_memory_) {
        r->image_ = XGetImage(
    	    dpy, r->pixmap_, 0, 0, r->pwidth_, r->pheight_, AllPlanes, ZPixmap
        );
    }
}

Raster::Raster(const Raster& raster) {
    RasterRep* r = new RasterRep;
    rep_ = r;
    raster.flush();
    RasterRep& rr = *(raster.rep());
    r->display_ = rr.display_;
    r->modified_ = true;
    r->width_ = rr.width_;
    r->height_ = rr.height_;
    r->left_ = rr.left_;
    r->bottom_ = rr.bottom_;
    r->right_ = rr.right_;
    r->top_ = rr.top_;
    r->pwidth_ = rr.pwidth_;
    r->pheight_ = rr.pheight_;
    r->shared_memory_ = false;

    DisplayRep* dr = r->display_->rep();
    XDisplay* dpy = dr->display_;
    r->pixmap_ = XCreatePixmap(
	dpy, dr->root_, r->pwidth_, r->pheight_, dr->default_visual_->depth()
    );
    r->gc_ = XCreateGC(dpy, r->pixmap_, 0, nil);
    XCopyArea(
	dpy, rr.pixmap_, r->pixmap_, r->gc_,
	0, 0, r->pwidth_, r->pheight_, 0, 0
    );

#ifdef XSHM
    init_shared_memory();
#endif

    if (!r->shared_memory_) {
        r->image_ = XGetImage(
    	    dpy, r->pixmap_, 0, 0, r->pwidth_, r->pheight_, AllPlanes, ZPixmap
        );
    }
}

Raster::Raster(RasterRep* r) { rep_ = r; }

Raster::~Raster() {
    RasterRep* r = rep();
    if (r->image_) {
        XDisplay* dpy = r->display_->rep()->display_;
        XFreePixmap(dpy, r->pixmap_);
        XFreeGC(dpy, r->gc_);

        XDestroyImage(r->image_);

#ifdef XSHM
        if (r->shared_memory_) {
            RasterRep::free_shared_memory(*r->display_, r->shminfo_);
        }
#endif

    }
    delete r;
}

boolean Raster::init_shared_memory() {
#ifdef XSHM
    RasterRep* r = rep();
    return RasterRep::init_shared_memory(
        r->shared_memory_, *r->display_, r->shminfo_, r->pwidth_, r->pheight_,
        r->image_, r->pixmap_ 
    );
#else
    return false;
#endif
}


#ifdef XSHM

/* static */ void RasterRep::free_shared_memory(
    Display& idpy, XShmSegmentInfo& shminfo
) {
    XDisplay* dpy = idpy.rep()->display_;

    XShmDetach(dpy, &shminfo);
    XSync(dpy, False);
    shmdt(shminfo.shmaddr);
}


/* static */ boolean RasterRep::init_shared_memory(
    boolean& shared_memory, Display& idpy, XShmSegmentInfo& shminfo,
    unsigned int pwidth, unsigned int pheight, XImage*& image, Pixmap pixmap
) {

    DisplayRep* dr = idpy.rep();
    XDisplay* dpy = dr->display_;

    int i;
    shared_memory = XShmQueryExtension(dpy) ? true : false; 
    boolean pixmaps;
    int *major, *minor;
    if (shared_memory) {
      int major, minor, pixmaps;
      XShmQueryVersion(dpy, &major, &minor, &pixmaps);
      shared_memory = pixmaps;
    }

    if (shared_memory) {
        image = XShmCreateImage(
          dpy, dr->default_visual_->visual(), dr->default_visual_->depth(),
          ZPixmap, 0, &shminfo, pwidth, pheight
        );

        shminfo.shmid = shmget(IPC_PRIVATE,
          image->bytes_per_line * image->height, IPC_CREAT|0777);

        shared_memory = shminfo.shmid >= 0;

        if (shared_memory) {
            shminfo.shmaddr = (char*)shmat(shminfo.shmid, 0, 0);
            image->data = shminfo.shmaddr;

            xerror_alert = false;
            XErrorHandler xh = XSetErrorHandler(XError);
            shminfo.readOnly = False;
            XShmAttach(dpy, &shminfo);
            XSync(dpy, False);
            XSetErrorHandler(xh);

            if (xerror_alert) {
                cerr << "unable to attach calling XShmAttach\n";
                shared_memory = false;
            
                // cleanup

                image->data = nil;
                XDestroyImage(image);
                image = nil;
                // XShmDetach(dpy, &shminfo);
                XSync(dpy, False); // necessary?
                shmdt(shminfo.shmaddr);
                shmctl(shminfo.shmid, IPC_RMID, 0);
            }
        }
    }

    if (shared_memory) {
        XShmGetImage(dpy, pixmap, image, 0, 0, AllPlanes);

        // removing the segment should cause the segment to be freed when
        // either the last process attached either detaches or terminates
        shmctl(shminfo.shmid, IPC_RMID, 0);
    }

#if 1
    static boolean announce;
    if (!announce) {
        if (shared_memory) {
            cerr << "using X shared memory extensions" << endl;
        }
        else {
            cerr << "NOT using X shared memory extensions" << endl;;
        }
        announce = true;
    }
#endif

   return shared_memory;
}

#endif

Coord Raster::width() const { return rep()->width_; }
Coord Raster::height() const { return rep()->height_; }
unsigned long Raster::pwidth() const { return rep()->pwidth_; }
unsigned long Raster::pheight() const { return rep()->pheight_; }

Coord Raster::left_bearing() const { return -rep()->left_; }
Coord Raster::right_bearing() const { return rep()->right_; }
Coord Raster::ascent() const { return rep()->top_; }
Coord Raster::descent() const { return -rep()->bottom_; }

void Raster::peek(
    unsigned long x, unsigned long y,
    ColorIntensity& red, ColorIntensity& green, ColorIntensity& blue,
    float& alpha
) const {
    register RasterRep* r = rep();
    unsigned long pixel = XGetPixel(
	r->image_, (unsigned int)x, r->pheight_ - (unsigned int)y - 1
    );
    XColor xc;
    r->display_->rep()->default_visual_->find_color(pixel, xc);
    red = float(xc.red) / 0xffff;
    green = float(xc.green) / 0xffff;
    blue = float(xc.blue) / 0xffff;
    alpha = 1.0;
}

void Raster::poke(
    unsigned long x, unsigned long y,
    ColorIntensity red, ColorIntensity green, ColorIntensity blue, float
) {
    RasterRep* r = rep();
    unsigned short sr = (unsigned short)(red * 0xffff);
    unsigned short sg = (unsigned short)(green * 0xffff);
    unsigned short sb = (unsigned short)(blue * 0xffff);
    XColor xc;
    r->display_->rep()->default_visual_->find_color(sr, sg, sb, xc);
    XPutPixel(
	r->image_, (unsigned int)x, r->pheight_ - (unsigned int)y - 1, xc.pixel
    );
    r->modified_ = true;
}

#ifdef XSHM 
static Bool completion(XDisplay* d, XEvent* eventp, char* arg) {
    return eventp->xany.type == (XShmGetEventBase(d) + ShmCompletion);
}
#endif

void Raster::flush() const {
    RasterRep* r = rep();
    if (r->modified_) {

#ifdef XSHM
        if (r->shared_memory_) {
            XShmPutImage(
	        r->display_->rep()->display_, r->pixmap_, r->gc_, r->image_,
	        0, 0, 0, 0, r->pwidth_, r->pheight_, True
            );
            XEvent xe;
            // thank god for this routine
            XIfEvent(r->display_->rep()->display_, &xe, completion, nil);
        }
#endif
        if (!r->shared_memory_) {
	    XPutImage(
	        r->display_->rep()->display_, r->pixmap_, r->gc_, r->image_,
	        0, 0, 0, 0, r->pwidth_, r->pheight_
	    );
        }
	r->modified_ = false;
    }
}


void Raster::flushrect(IntCoord left, IntCoord bottom, 
		       IntCoord right, IntCoord top) const {
//  cerr << "Raster::flushrect l,b,r,t " <<
//    left << "," << bottom << "," <<
//    right << "," << top << "\n";
  RasterRep* r = rep();
  if (r->pixmap_)
    {
      if (r->modified_) {
	
#ifdef XSHM
	if (r->shared_memory_) {
//	  cerr << "Raster::flushrect args to XShmPutImage " <<
//	     "...," << 
//	    left << "," <<  r->pheight_ - top - 1 << "," <<
//	    left << "," <<  r->pheight_ - top - 1 << "," <<
//	    right-left+1 << "," << top-bottom+1 << "\n";
	  XShmPutImage(
		       r->display_->rep()->display_, r->pixmap_, r->gc_, r->image_,
		       left, r->pheight_ - top - 1,
		       left, r->pheight_ - top - 1,
		       right-left+1, top-bottom+1, True
		       );
	XEvent xe;
	// thank god for this routine
	XIfEvent(r->display_->rep()->display_, &xe, completion, nil);
	}
#endif
	if (!r->shared_memory_) {
	  XPutImage(
		    r->display_->rep()->display_, r->pixmap_, r->gc_, r->image_,
		    left, r->pheight_ - top - 1,
		    left, r->pheight_ - top - 1,
		    right-left+1, top-bottom+1
		    );
	}
	r->modified_ = false;
      }
    }
}