/**********************************************************
 * Copyright 2008-2009 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, sublicense, 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 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
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
 * 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.
 *
 **********************************************************/

#include "pipe/p_state.h"
#include "pipe/p_context.h"
#include "util/u_memory.h"

#include "svga_cmd.h"
#include "svga_context.h"
#include "svga_screen.h"
#include "svga_resource_buffer.h"
#include "svga_winsys.h"
#include "svga_debug.h"


/* Fixme: want a public base class for all pipe structs, even if there
 * isn't much in them.
 */
struct pipe_query {
   int dummy;
};

struct svga_query {
   struct pipe_query base;
   SVGA3dQueryType type;
   struct svga_winsys_buffer *hwbuf;
   volatile SVGA3dQueryResult *queryResult;
   struct pipe_fence_handle *fence;
};

/***********************************************************************
 * Inline conversion functions.  These are better-typed than the
 * macros used previously:
 */
static INLINE struct svga_query *
svga_query( struct pipe_query *q )
{
   return (struct svga_query *)q;
}

static boolean svga_get_query_result(struct pipe_context *pipe, 
                                     struct pipe_query *q,
                                     boolean wait,
                                     union pipe_query_result *result);

static struct pipe_query *svga_create_query( struct pipe_context *pipe,
                                             unsigned query_type )
{
   struct svga_context *svga = svga_context( pipe );
   struct svga_screen *svgascreen = svga_screen(pipe->screen);
   struct svga_winsys_screen *sws = svgascreen->sws;
   struct svga_query *sq;

   SVGA_DBG(DEBUG_QUERY, "%s\n", __FUNCTION__);

   sq = CALLOC_STRUCT(svga_query);
   if (!sq)
      goto no_sq;

   sq->type = SVGA3D_QUERYTYPE_OCCLUSION;

   sq->hwbuf = svga_winsys_buffer_create(svga,
                                         1,
                                         SVGA_BUFFER_USAGE_PINNED,
                                         sizeof *sq->queryResult);
   if(!sq->hwbuf)
      goto no_hwbuf;
    
   sq->queryResult = (SVGA3dQueryResult *)sws->buffer_map(sws, 
                                                          sq->hwbuf, 
                                                          PIPE_TRANSFER_WRITE);
   if(!sq->queryResult)
      goto no_query_result;

   sq->queryResult->totalSize = sizeof *sq->queryResult;
   sq->queryResult->state = SVGA3D_QUERYSTATE_NEW;

   /*
    * We request the buffer to be pinned and assume it is always mapped.
    * 
    * The reason is that we don't want to wait for fences when checking the
    * query status.
    */
   sws->buffer_unmap(sws, sq->hwbuf);

   return &sq->base;

no_query_result:
   sws->buffer_destroy(sws, sq->hwbuf);
no_hwbuf:
   FREE(sq);
no_sq:
   return NULL;
}

static void svga_destroy_query(struct pipe_context *pipe,
                               struct pipe_query *q)
{
   struct svga_screen *svgascreen = svga_screen(pipe->screen);
   struct svga_winsys_screen *sws = svgascreen->sws;
   struct svga_query *sq = svga_query( q );

   SVGA_DBG(DEBUG_QUERY, "%s\n", __FUNCTION__);
   sws->buffer_destroy(sws, sq->hwbuf);
   sws->fence_reference(sws, &sq->fence, NULL);
   FREE(sq);
}

static void svga_begin_query(struct pipe_context *pipe, 
                             struct pipe_query *q)
{
   struct svga_screen *svgascreen = svga_screen(pipe->screen);
   struct svga_winsys_screen *sws = svgascreen->sws;
   struct svga_context *svga = svga_context( pipe );
   struct svga_query *sq = svga_query( q );
   enum pipe_error ret;

   SVGA_DBG(DEBUG_QUERY, "%s\n", __FUNCTION__);
   
   assert(!svga->sq);

   /* Need to flush out buffered drawing commands so that they don't
    * get counted in the query results.
    */
   svga_hwtnl_flush_retry(svga);
   
   if(sq->queryResult->state == SVGA3D_QUERYSTATE_PENDING) {
      /* The application doesn't care for the pending query result. We cannot
       * let go the existing buffer and just get a new one because its storage
       * may be reused for other purposes and clobbered by the host when it
       * determines the query result. So the only option here is to wait for
       * the existing query's result -- not a big deal, given that no sane
       * application would do this.
       */
      uint64_t result;

      svga_get_query_result(pipe, q, TRUE, (void*)&result);
      
      assert(sq->queryResult->state != SVGA3D_QUERYSTATE_PENDING);
   }
   
   sq->queryResult->state = SVGA3D_QUERYSTATE_NEW;
   sws->fence_reference(sws, &sq->fence, NULL);

   ret = SVGA3D_BeginQuery(svga->swc, sq->type);
   if(ret != PIPE_OK) {
      svga_context_flush(svga, NULL);
      ret = SVGA3D_BeginQuery(svga->swc, sq->type);
      assert(ret == PIPE_OK);
   }

   svga->sq = sq;
}

static void svga_end_query(struct pipe_context *pipe, 
                           struct pipe_query *q)
{
   struct svga_context *svga = svga_context( pipe );
   struct svga_query *sq = svga_query( q );
   enum pipe_error ret;

   SVGA_DBG(DEBUG_QUERY, "%s\n", __FUNCTION__);
   assert(svga->sq == sq);

   svga_hwtnl_flush_retry(svga);
   
   /* Set to PENDING before sending EndQuery. */
   sq->queryResult->state = SVGA3D_QUERYSTATE_PENDING;

   ret = SVGA3D_EndQuery( svga->swc, sq->type, sq->hwbuf);
   if(ret != PIPE_OK) {
      svga_context_flush(svga, NULL);
      ret = SVGA3D_EndQuery( svga->swc, sq->type, sq->hwbuf);
      assert(ret == PIPE_OK);
   }
   
   /* TODO: Delay flushing. We don't really need to flush here, just ensure 
    * that there is one flush before svga_get_query_result attempts to get the
    * result */
   svga_context_flush(svga, NULL);

   svga->sq = NULL;
}

static boolean svga_get_query_result(struct pipe_context *pipe, 
                                     struct pipe_query *q,
                                     boolean wait,
                                     union pipe_query_result *vresult)
{
   struct svga_context *svga = svga_context( pipe );
   struct svga_screen *svgascreen = svga_screen( pipe->screen );
   struct svga_winsys_screen *sws = svgascreen->sws;
   struct svga_query *sq = svga_query( q );
   SVGA3dQueryState state;
   uint64_t *result = (uint64_t*)vresult;
   
   SVGA_DBG(DEBUG_QUERY, "%s wait: %d\n", __FUNCTION__);

   /* The query status won't be updated by the host unless 
    * SVGA_3D_CMD_WAIT_FOR_QUERY is emitted. Unfortunately this will cause a 
    * synchronous wait on the host */
   if(!sq->fence) {
      enum pipe_error ret;

      ret = SVGA3D_WaitForQuery( svga->swc, sq->type, sq->hwbuf);
      if(ret != PIPE_OK) {
         svga_context_flush(svga, NULL);
         ret = SVGA3D_WaitForQuery( svga->swc, sq->type, sq->hwbuf);
         assert(ret == PIPE_OK);
      }
   
      svga_context_flush(svga, &sq->fence);
      
      assert(sq->fence);
   }

   state = sq->queryResult->state;
   if(state == SVGA3D_QUERYSTATE_PENDING) {
      if(!wait)
         return FALSE;
   
      sws->fence_finish(sws, sq->fence, SVGA_FENCE_FLAG_QUERY);
      
      state = sq->queryResult->state;
   }

   assert(state == SVGA3D_QUERYSTATE_SUCCEEDED || 
          state == SVGA3D_QUERYSTATE_FAILED);
   
   *result = (uint64_t)sq->queryResult->result32;

   SVGA_DBG(DEBUG_QUERY, "%s result %d\n", __FUNCTION__, (unsigned)*result);

   return TRUE;
}


void svga_init_query_functions( struct svga_context *svga )
{
   svga->pipe.create_query = svga_create_query;
   svga->pipe.destroy_query = svga_destroy_query;
   svga->pipe.begin_query = svga_begin_query;
   svga->pipe.end_query = svga_end_query;
   svga->pipe.get_query_result = svga_get_query_result;
}