/**************************************************************************
 *
 * Copyright 2009, VMware, Inc.
 * All Rights Reserved.
 * Copyright 2010 George Sapountzis <gsapountzis@gmail.com>
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the
 * "Software"), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish,
 * distribute, sub license, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject to
 * the following conditions:
 *
 * The above copyright notice and this permission notice (including the
 * next paragraph) shall be included in all copies or substantial portions
 * of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
 * IN NO EVENT SHALL VMWARE AND/OR ITS SUPPLIERS BE LIABLE FOR
 * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 *
 **************************************************************************/

/* TODO:
 *
 * stride:
 *
 * The driver and the loaders (libGL, xserver/glx) compute the stride from the
 * width independently. winsys has a workaround that works for softpipe but may
 * explode for other drivers or platforms, rendering- or performance-wise.
 * Solving this issue properly requires extending the DRISW loader extension,
 * in order to make the stride available to the putImage callback.
 *
 * drisw_api:
 *
 * Define drisw_api similarly to dri_api and use it to call the loader. This is
 * predicated on support for calling the loader from the winsys, which has to
 * grow for DRI2 as well.
 *
 * xshm:
 *
 * Allow the loaders to use the XSHM extension. It probably requires callbacks
 * for createImage/destroyImage similar to DRI2 getBuffers. Probably not worth
 * it, given the scope of DRISW, unless it falls naturally from properly
 * solving the above two issues.
 *
 * swrast_create_screen:
 *
 * Allow for any software renderer to be used. Factor out the code from
 * targets/libgl-xlib/xlib.c, put it in targets/common or winsys/sw/common and
 * use it in all software targets.
 */

#include "util/u_memory.h"
#include "util/u_inlines.h"
#include "pipe/p_context.h"
#include "state_tracker/drm_api.h"

#include "dri_screen.h"
#include "dri_context.h"
#include "dri_drawable.h"
#include "dri_st_api.h"
#include "dri1_helper.h"
#include "drisw.h"


static INLINE void
get_drawable_info(__DRIdrawable *dPriv, int *w, int *h)
{
   __DRIscreen *sPriv = dPriv->driScreenPriv;
   const __DRIswrastLoaderExtension *loader = sPriv->swrast_loader;
   int x, y;

   loader->getDrawableInfo(dPriv,
                           &x, &y, w, h,
                           dPriv->loaderPrivate);
}

static INLINE void
put_image(__DRIdrawable *dPriv, void *data)
{
   __DRIscreen *sPriv = dPriv->driScreenPriv;
   const __DRIswrastLoaderExtension *loader = sPriv->swrast_loader;

   loader->putImage(dPriv, __DRI_SWRAST_IMAGE_OP_SWAP,
                    0, 0, dPriv->w, dPriv->h,
                    data, dPriv->loaderPrivate);
}

void
drisw_update_drawable_info(__DRIdrawable *dPriv)
{
   get_drawable_info(dPriv, &dPriv->w, &dPriv->h);
}

static INLINE void
drisw_present_texture(__DRIdrawable *dPriv,
                      struct pipe_texture *ptex)
{
   struct dri_drawable *drawable = dri_drawable(dPriv);
   struct dri_screen *screen = dri_screen(drawable->sPriv);
   struct pipe_context *pipe;
   struct pipe_surface *psurf;
   struct pipe_transfer *ptrans;
   void *pmap;

   pipe = dri1_get_pipe_context(screen);
   psurf = dri1_get_pipe_surface(drawable, ptex);
   if (!pipe || !psurf)
      return;

   ptrans = pipe->get_tex_transfer(pipe, ptex, 0, 0, 0,
                                   PIPE_TRANSFER_READ,
                                   0, 0, dPriv->w, dPriv->h);

   pmap = pipe->transfer_map(pipe, ptrans);

   assert(pmap);

   put_image(dPriv, pmap);

   pipe->transfer_unmap(pipe, ptrans);

   pipe->tex_transfer_destroy(pipe, ptrans);
}

static INLINE void
drisw_invalidate_drawable(__DRIdrawable *dPriv)
{
   struct dri_context *ctx = dri_get_current();
   struct dri_drawable *drawable = dri_drawable(dPriv);

   drawable->texture_stamp = dPriv->lastStamp - 1;

   /* check if swapping currently bound buffer */
   if (ctx && ctx->dPriv == dPriv)
      ctx->st->notify_invalid_framebuffer(ctx->st, drawable->stfb);
}

static INLINE void
drisw_copy_to_front(__DRIdrawable * dPriv,
                    struct pipe_texture *ptex)
{
   drisw_present_texture(dPriv, ptex);

   drisw_invalidate_drawable(dPriv);
}

/*
 * Backend functions for st_framebuffer interface and swap_buffers.
 */

void
drisw_flush_frontbuffer(struct dri_drawable *drawable,
                        enum st_attachment_type statt)
{
   struct dri_context *ctx = dri_get_current();
   struct pipe_texture *ptex;

   if (!ctx)
      return;

   ptex = drawable->textures[statt];

   if (ptex) {
      drisw_copy_to_front(ctx->dPriv, ptex);
   }
}

void
drisw_swap_buffers(__DRIdrawable *dPriv)
{
   struct dri_context *ctx = dri_get_current();
   struct dri_drawable *drawable = dri_drawable(dPriv);
   struct pipe_texture *ptex;

   if (!ctx)
      return;

   ptex = drawable->textures[ST_ATTACHMENT_BACK_LEFT];

   if (ptex) {
      ctx->st->flush(ctx->st, PIPE_FLUSH_RENDER_CACHE, NULL);

      drisw_copy_to_front(dPriv, ptex);
   }
}

/**
 * Allocate framebuffer attachments.
 *
 * During fixed-size operation, the function keeps allocating new attachments
 * as they are requested. Unused attachments are not removed, not until the
 * framebuffer is resized or destroyed.
 *
 * It should be possible for DRI1 and DRISW to share this function, but it
 * seems a better seperation and safer for each DRI version to provide its own
 * function.
 */
void
drisw_allocate_textures(struct dri_drawable *drawable,
                        unsigned mask)
{
   struct dri_screen *screen = dri_screen(drawable->sPriv);
   struct pipe_texture templ;
   unsigned width, height;
   boolean resized;
   int i;

   width  = drawable->dPriv->w;
   height = drawable->dPriv->h;

   resized = (drawable->old_w != width ||
              drawable->old_h != height);

   /* remove outdated textures */
   if (resized) {
      for (i = 0; i < ST_ATTACHMENT_COUNT; i++)
         pipe_texture_reference(&drawable->textures[i], NULL);
   }

   memset(&templ, 0, sizeof(templ));
   templ.target = PIPE_TEXTURE_2D;
   templ.width0 = width;
   templ.height0 = height;
   templ.depth0 = 1;
   templ.last_level = 0;

   for (i = 0; i < ST_ATTACHMENT_COUNT; i++) {
      enum pipe_format format;
      unsigned tex_usage;

      /* the texture already exists or not requested */
      if (drawable->textures[i] || !(mask & (1 << i))) {
         continue;
      }

      switch (i) {
      case ST_ATTACHMENT_FRONT_LEFT:
      case ST_ATTACHMENT_BACK_LEFT:
      case ST_ATTACHMENT_FRONT_RIGHT:
      case ST_ATTACHMENT_BACK_RIGHT:
         format = drawable->stvis.color_format;
         tex_usage = PIPE_TEXTURE_USAGE_DISPLAY_TARGET |
                     PIPE_TEXTURE_USAGE_RENDER_TARGET;
         break;
      case ST_ATTACHMENT_DEPTH_STENCIL:
         format = drawable->stvis.depth_stencil_format;
         tex_usage = PIPE_TEXTURE_USAGE_DEPTH_STENCIL;
         break;
      default:
         format = PIPE_FORMAT_NONE;
         break;
      }

      if (format != PIPE_FORMAT_NONE) {
         templ.format = format;
         templ.tex_usage = tex_usage;

         drawable->textures[i] =
            screen->pipe_screen->texture_create(screen->pipe_screen, &templ);
      }
   }

   drawable->old_w = width;
   drawable->old_h = height;
}

/*
 * Backend function for init_screen.
 */

static const __DRIextension *drisw_screen_extensions[] = {
   NULL
};

const __DRIconfig **
drisw_init_screen(__DRIscreen * sPriv)
{
   struct dri_screen *screen;
   struct drm_create_screen_arg arg;

   screen = CALLOC_STRUCT(dri_screen);
   if (!screen)
      return NULL;

   screen->api = drm_api_create();
   screen->sPriv = sPriv;
   screen->fd = -1;
   sPriv->private = (void *)screen;
   sPriv->extensions = drisw_screen_extensions;
   arg.mode = DRM_CREATE_DRISW;

   screen->pipe_screen = screen->api->create_screen(screen->api, -1, &arg);
   if (!screen->pipe_screen) {
      debug_printf("%s: failed to create pipe_screen\n", __FUNCTION__);
      goto fail;
   }

   screen->smapi = dri_create_st_manager(screen);
   if (!screen->smapi)
      goto fail;

   driParseOptionInfo(&screen->optionCache,
                      __driConfigOptions, __driNConfigOptions);

   return dri_fill_in_modes(screen, 32);
fail:
   dri_destroy_screen(sPriv);
   return NULL;
}

/* This is the table of extensions that the loader will dlsym() for. */
PUBLIC const __DRIextension *__driDriverExtensions[] = {
    &driCoreExtension.base,
    &driSWRastExtension.base,
    NULL
};

/* vim: set sw=3 ts=8 sts=3 expandtab: */