/**************************************************************************
 *
 * Copyright 2009, VMware, Inc.
 * All Rights Reserved.
 *
 * 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.
 *
 **************************************************************************/
/*
 * Author: Keith Whitwell <keithw@vmware.com>
 * Author: Jakob Bornecrantz <wallbraker@gmail.com>
 */

#include "dri_screen.h"
#include "dri_context.h"
#include "dri_drawable.h"

#include "pipe/p_screen.h"
#include "util/u_format.h"
#include "util/u_memory.h"
#include "util/u_inlines.h"

static void
swap_fences_unref(struct dri_drawable *draw);

static boolean
dri_st_framebuffer_validate(struct st_context_iface *stctx,
                            struct st_framebuffer_iface *stfbi,
                            const enum st_attachment_type *statts,
                            unsigned count,
                            struct pipe_resource **out)
{
   struct dri_context *ctx = (struct dri_context *)stctx->st_manager_private;
   struct dri_drawable *drawable =
      (struct dri_drawable *) stfbi->st_manager_private;
   struct dri_screen *screen = dri_screen(drawable->sPriv);
   unsigned statt_mask, new_mask;
   boolean new_stamp;
   int i;
   unsigned int lastStamp;
   struct pipe_resource **textures =
      drawable->stvis.samples > 1 ? drawable->msaa_textures
                                  : drawable->textures;

   statt_mask = 0x0;
   for (i = 0; i < count; i++)
      statt_mask |= (1 << statts[i]);

   /* record newly allocated textures */
   new_mask = (statt_mask & ~drawable->texture_mask);

   /*
    * dPriv->dri2.stamp is the server stamp.  dPriv->lastStamp is the
    * client stamp.  It has the value of the server stamp when last
    * checked.
    */
   do {
      lastStamp = drawable->dPriv->lastStamp;
      new_stamp = (drawable->texture_stamp != lastStamp);

      if (new_stamp || new_mask || screen->broken_invalidate) {
         if (new_stamp && drawable->update_drawable_info)
            drawable->update_drawable_info(drawable);

         drawable->allocate_textures(ctx, drawable, statts, count);

         /* add existing textures */
         for (i = 0; i < ST_ATTACHMENT_COUNT; i++) {
            if (textures[i])
               statt_mask |= (1 << i);
         }

         drawable->texture_stamp = lastStamp;
         drawable->texture_mask = statt_mask;
      }
   } while (lastStamp != drawable->dPriv->lastStamp);

   if (!out)
      return TRUE;

   /* Set the window-system buffers for the state tracker. */
   for (i = 0; i < count; i++) {
      out[i] = NULL;
      pipe_resource_reference(&out[i], textures[statts[i]]);
   }

   return TRUE;
}

static boolean
dri_st_framebuffer_flush_front(struct st_context_iface *stctx,
                               struct st_framebuffer_iface *stfbi,
                               enum st_attachment_type statt)
{
   struct dri_context *ctx = (struct dri_context *)stctx->st_manager_private;
   struct dri_drawable *drawable =
      (struct dri_drawable *) stfbi->st_manager_private;

   /* XXX remove this and just set the correct one on the framebuffer */
   drawable->flush_frontbuffer(ctx, drawable, statt);

   return TRUE;
}

/**
 * This is called when we need to set up GL rendering to a new X window.
 */
boolean
dri_create_buffer(__DRIscreen * sPriv,
		  __DRIdrawable * dPriv,
		  const struct gl_config * visual, boolean isPixmap)
{
   struct dri_screen *screen = sPriv->driverPrivate;
   struct dri_drawable *drawable = NULL;

   if (isPixmap)
      goto fail;		       /* not implemented */

   drawable = CALLOC_STRUCT(dri_drawable);
   if (drawable == NULL)
      goto fail;

   dri_fill_st_visual(&drawable->stvis, screen, visual);

   /* setup the st_framebuffer_iface */
   drawable->base.visual = &drawable->stvis;
   drawable->base.flush_front = dri_st_framebuffer_flush_front;
   drawable->base.validate = dri_st_framebuffer_validate;
   drawable->base.st_manager_private = (void *) drawable;

   drawable->screen = screen;
   drawable->sPriv = sPriv;
   drawable->dPriv = dPriv;
   drawable->desired_fences = screen->default_throttle_frames;
   if (drawable->desired_fences > DRI_SWAP_FENCES_MAX)
      drawable->desired_fences = DRI_SWAP_FENCES_MAX;

   dPriv->driverPrivate = (void *)drawable;
   p_atomic_set(&drawable->base.stamp, 1);

   return GL_TRUE;
fail:
   FREE(drawable);
   return GL_FALSE;
}

void
dri_destroy_buffer(__DRIdrawable * dPriv)
{
   struct dri_drawable *drawable = dri_drawable(dPriv);
   int i;

   pipe_surface_reference(&drawable->drisw_surface, NULL);

   for (i = 0; i < ST_ATTACHMENT_COUNT; i++)
      pipe_resource_reference(&drawable->textures[i], NULL);
   for (i = 0; i < ST_ATTACHMENT_COUNT; i++)
      pipe_resource_reference(&drawable->msaa_textures[i], NULL);

   swap_fences_unref(drawable);

   FREE(drawable);
}

/**
 * Validate the texture at an attachment.  Allocate the texture if it does not
 * exist.  Used by the TFP extension.
 */
static void
dri_drawable_validate_att(struct dri_context *ctx,
                          struct dri_drawable *drawable,
                          enum st_attachment_type statt)
{
   enum st_attachment_type statts[ST_ATTACHMENT_COUNT];
   unsigned i, count = 0;

   /* check if buffer already exists */
   if (drawable->texture_mask & (1 << statt))
      return;

   /* make sure DRI2 does not destroy existing buffers */
   for (i = 0; i < ST_ATTACHMENT_COUNT; i++) {
      if (drawable->texture_mask & (1 << i)) {
         statts[count++] = i;
      }
   }
   statts[count++] = statt;

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

   drawable->base.validate(ctx->st, &drawable->base, statts, count, NULL);
}

/**
 * These are used for GLX_EXT_texture_from_pixmap
 */
static void
dri_set_tex_buffer2(__DRIcontext *pDRICtx, GLint target,
                    GLint format, __DRIdrawable *dPriv)
{
   struct dri_context *ctx = dri_context(pDRICtx);
   struct dri_drawable *drawable = dri_drawable(dPriv);
   struct pipe_resource *pt;

   dri_drawable_validate_att(ctx, drawable, ST_ATTACHMENT_FRONT_LEFT);

   /* Use the pipe resource associated with the X drawable */
   pt = drawable->textures[ST_ATTACHMENT_FRONT_LEFT];

   if (pt) {
      enum pipe_format internal_format = pt->format;

      if (format == __DRI_TEXTURE_FORMAT_RGB)  {
         /* only need to cover the formats recognized by dri_fill_st_visual */
         switch (internal_format) {
         case PIPE_FORMAT_B8G8R8A8_UNORM:
            internal_format = PIPE_FORMAT_B8G8R8X8_UNORM;
            break;
         case PIPE_FORMAT_A8R8G8B8_UNORM:
            internal_format = PIPE_FORMAT_X8R8G8B8_UNORM;
            break;
         default:
            break;
         }
      }

      drawable->update_tex_buffer(drawable, ctx, pt);

      ctx->st->teximage(ctx->st,
            (target == GL_TEXTURE_2D) ? ST_TEXTURE_2D : ST_TEXTURE_RECT,
            0, internal_format, pt, FALSE);
   }
}

static void
dri_set_tex_buffer(__DRIcontext *pDRICtx, GLint target,
                   __DRIdrawable *dPriv)
{
   dri_set_tex_buffer2(pDRICtx, target, __DRI_TEXTURE_FORMAT_RGBA, dPriv);
}

const __DRItexBufferExtension driTexBufferExtension = {
    { __DRI_TEX_BUFFER, __DRI_TEX_BUFFER_VERSION },
   dri_set_tex_buffer,
   dri_set_tex_buffer2,
   NULL,
};

/**
 * Get the format and binding of an attachment.
 */
void
dri_drawable_get_format(struct dri_drawable *drawable,
                        enum st_attachment_type statt,
                        enum pipe_format *format,
                        unsigned *bind)
{
   switch (statt) {
   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;
      *bind = PIPE_BIND_RENDER_TARGET | PIPE_BIND_SAMPLER_VIEW;
      break;
   case ST_ATTACHMENT_DEPTH_STENCIL:
      *format = drawable->stvis.depth_stencil_format;
      *bind = PIPE_BIND_DEPTH_STENCIL; /* XXX sampler? */
      break;
   default:
      *format = PIPE_FORMAT_NONE;
      *bind = 0;
      break;
   }
}


/**
 * swap_fences_pop_front - pull a fence from the throttle queue
 *
 * If the throttle queue is filled to the desired number of fences,
 * pull fences off the queue until the number is less than the desired
 * number of fences, and return the last fence pulled.
 */
static struct pipe_fence_handle *
swap_fences_pop_front(struct dri_drawable *draw)
{
   struct pipe_screen *screen = draw->screen->base.screen;
   struct pipe_fence_handle *fence = NULL;

   if (draw->desired_fences == 0)
      return NULL;

   if (draw->cur_fences >= draw->desired_fences) {
      screen->fence_reference(screen, &fence, draw->swap_fences[draw->tail]);
      screen->fence_reference(screen, &draw->swap_fences[draw->tail++], NULL);
      draw->tail &= DRI_SWAP_FENCES_MASK;
      --draw->cur_fences;
   }
   return fence;
}


/**
 * swap_fences_push_back - push a fence onto the throttle queue
 *
 * push a fence onto the throttle queue and pull fences of the queue
 * so that the desired number of fences are on the queue.
 */
static void
swap_fences_push_back(struct dri_drawable *draw,
		      struct pipe_fence_handle *fence)
{
   struct pipe_screen *screen = draw->screen->base.screen;

   if (!fence || draw->desired_fences == 0)
      return;

   while(draw->cur_fences == draw->desired_fences)
      swap_fences_pop_front(draw);

   draw->cur_fences++;
   screen->fence_reference(screen, &draw->swap_fences[draw->head++],
			   fence);
   draw->head &= DRI_SWAP_FENCES_MASK;
}


/**
 * swap_fences_unref - empty the throttle queue
 *
 * pulls fences of the throttle queue until it is empty.
 */
static void
swap_fences_unref(struct dri_drawable *draw)
{
   struct pipe_screen *screen = draw->screen->base.screen;

   while(draw->cur_fences) {
      screen->fence_reference(screen, &draw->swap_fences[draw->tail++], NULL);
      draw->tail &= DRI_SWAP_FENCES_MASK;
      --draw->cur_fences;
   }
}

void
dri_pipe_blit(struct pipe_context *pipe,
              struct pipe_resource *dst,
              struct pipe_resource *src)
{
   struct pipe_blit_info blit;

   if (!dst || !src)
      return;

   /* From the GL spec, version 4.2, section 4.1.11 (Additional Multisample
    *  Fragment Operations):
    *
    *      If a framebuffer object is not bound, after all operations have
    *      been completed on the multisample buffer, the sample values for
    *      each color in the multisample buffer are combined to produce a
    *      single color value, and that value is written into the
    *      corresponding color buffers selected by DrawBuffer or
    *      DrawBuffers. An implementation may defer the writing of the color
    *      buffers until a later time, but the state of the framebuffer must
    *      behave as if the color buffers were updated as each fragment was
    *      processed. The method of combination is not specified. If the
    *      framebuffer contains sRGB values, then it is recommended that the
    *      an average of sample values is computed in a linearized space, as
    *      for blending (see section 4.1.7).
    *
    * In other words, to do a resolve operation in a linear space, we have
    * to set sRGB formats if the original resources were sRGB, so don't use
    * util_format_linear.
    */

   memset(&blit, 0, sizeof(blit));
   blit.dst.resource = dst;
   blit.dst.box.width = dst->width0;
   blit.dst.box.height = dst->height0;
   blit.dst.box.depth = 1;
   blit.dst.format = dst->format;
   blit.src.resource = src;
   blit.src.box.width = src->width0;
   blit.src.box.height = src->height0;
   blit.src.box.depth = 1;
   blit.src.format = src->format;
   blit.mask = PIPE_MASK_RGBA;
   blit.filter = PIPE_TEX_FILTER_NEAREST;

   pipe->blit(pipe, &blit);
}

static void
dri_postprocessing(struct dri_context *ctx,
                   struct dri_drawable *drawable,
                   enum st_attachment_type att)
{
   struct pipe_resource *src = drawable->textures[att];
   struct pipe_resource *zsbuf = drawable->textures[ST_ATTACHMENT_DEPTH_STENCIL];

   if (ctx->pp && src && zsbuf)
      pp_run(ctx->pp, src, src, zsbuf);
}

/**
 * DRI2 flush extension, the flush_with_flags function.
 *
 * \param context           the context
 * \param drawable          the drawable to flush
 * \param flags             a combination of _DRI2_FLUSH_xxx flags
 * \param throttle_reason   the reason for throttling, 0 = no throttling
 */
void
dri_flush(__DRIcontext *cPriv,
          __DRIdrawable *dPriv,
          unsigned flags,
          enum __DRI2throttleReason reason)
{
   struct dri_context *ctx = dri_context(cPriv);
   struct dri_drawable *drawable = dri_drawable(dPriv);
   unsigned flush_flags;
   boolean swap_msaa_buffers = FALSE;

   if (!ctx) {
      assert(0);
      return;
   }

   if (drawable) {
      /* prevent recursion */
      if (drawable->flushing)
         return;

      drawable->flushing = TRUE;
   }
   else {
      flags &= ~__DRI2_FLUSH_DRAWABLE;
   }

   /* Flush the drawable. */
   if ((flags & __DRI2_FLUSH_DRAWABLE) &&
       drawable->textures[ST_ATTACHMENT_BACK_LEFT]) {
      struct pipe_context *pipe = ctx->st->pipe;

      if (drawable->stvis.samples > 1 &&
          reason == __DRI2_THROTTLE_SWAPBUFFER) {
         /* Resolve the MSAA back buffer. */
         dri_pipe_blit(ctx->st->pipe,
                       drawable->textures[ST_ATTACHMENT_BACK_LEFT],
                       drawable->msaa_textures[ST_ATTACHMENT_BACK_LEFT]);

         if (drawable->msaa_textures[ST_ATTACHMENT_FRONT_LEFT] &&
             drawable->msaa_textures[ST_ATTACHMENT_BACK_LEFT]) {
            swap_msaa_buffers = TRUE;
         }

         /* FRONT_LEFT is resolved in drawable->flush_frontbuffer. */
      }

      dri_postprocessing(ctx, drawable, ST_ATTACHMENT_BACK_LEFT);

      if (ctx->hud) {
         hud_draw(ctx->hud, drawable->textures[ST_ATTACHMENT_BACK_LEFT]);
      }

      pipe->flush_resource(pipe, drawable->textures[ST_ATTACHMENT_BACK_LEFT]);
   }

   flush_flags = 0;
   if (flags & __DRI2_FLUSH_CONTEXT)
      flush_flags |= ST_FLUSH_FRONT;
   if (reason == __DRI2_THROTTLE_SWAPBUFFER)
      flush_flags |= ST_FLUSH_END_OF_FRAME;

   /* Flush the context and throttle if needed. */
   if (dri_screen(ctx->sPriv)->throttling_enabled &&
       drawable &&
       (reason == __DRI2_THROTTLE_SWAPBUFFER ||
        reason == __DRI2_THROTTLE_FLUSHFRONT)) {
      /* Throttle.
       *
       * This pulls a fence off the throttling queue and waits for it if the
       * number of fences on the throttling queue has reached the desired
       * number.
       *
       * Then flushes to insert a fence at the current rendering position, and
       * pushes that fence on the queue. This requires that the st_context_iface
       * flush method returns a fence even if there are no commands to flush.
       */
      struct pipe_screen *screen = drawable->screen->base.screen;
      struct pipe_fence_handle *fence;

      fence = swap_fences_pop_front(drawable);
      if (fence) {
         (void) screen->fence_finish(screen, fence, PIPE_TIMEOUT_INFINITE);
         screen->fence_reference(screen, &fence, NULL);
      }

      ctx->st->flush(ctx->st, flush_flags, &fence);

      if (fence) {
         swap_fences_push_back(drawable, fence);
         screen->fence_reference(screen, &fence, NULL);
      }
   }
   else if (flags & (__DRI2_FLUSH_DRAWABLE | __DRI2_FLUSH_CONTEXT)) {
      ctx->st->flush(ctx->st, flush_flags, NULL);
   }

   if (drawable) {
      drawable->flushing = FALSE;
   }

   /* Swap the MSAA front and back buffers, so that reading
    * from the front buffer after SwapBuffers returns what was
    * in the back buffer.
    */
   if (swap_msaa_buffers) {
      struct pipe_resource *tmp =
         drawable->msaa_textures[ST_ATTACHMENT_FRONT_LEFT];

      drawable->msaa_textures[ST_ATTACHMENT_FRONT_LEFT] =
         drawable->msaa_textures[ST_ATTACHMENT_BACK_LEFT];
      drawable->msaa_textures[ST_ATTACHMENT_BACK_LEFT] = tmp;

      /* Now that we have swapped the buffers, this tells the state
       * tracker to revalidate the framebuffer.
       */
      p_atomic_inc(&drawable->base.stamp);
   }
}

/**
 * dri_throttle - A DRI2ThrottleExtension throttling function.
 */
static void
dri_throttle(__DRIcontext *cPriv, __DRIdrawable *dPriv,
             enum __DRI2throttleReason reason)
{
   dri_flush(cPriv, dPriv, 0, reason);
}


const __DRI2throttleExtension dri2ThrottleExtension = {
    .base = { __DRI2_THROTTLE, __DRI2_THROTTLE_VERSION },
    .throttle = dri_throttle,
};


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