/**************************************************************************
 * 
 * Copyright 2003 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.
 * 
 **************************************************************************/


#include <stdio.h>
#include "main/glheader.h"
#include "main/context.h"

#include "pipe/p_defines.h"
#include "st_context.h"
#include "st_atom.h"
#include "st_program.h"
#include "st_manager.h"

typedef void (*update_func_t)(struct st_context *st);

/* The list state update functions. */
static const update_func_t update_functions[] =
{
#define ST_STATE(FLAG, st_update) st_update,
#include "st_atom_list.h"
#undef ST_STATE
};


void st_init_atoms( struct st_context *st )
{
   STATIC_ASSERT(ARRAY_SIZE(update_functions) <= 64);
}


void st_destroy_atoms( struct st_context *st )
{
   /* no-op */
}


/* Too complex to figure out, just check every time:
 */
static void check_program_state( struct st_context *st )
{
   struct gl_context *ctx = st->ctx;
   struct st_vertex_program *old_vp = st->vp;
   struct st_common_program *old_tcp = st->tcp;
   struct st_common_program *old_tep = st->tep;
   struct st_common_program *old_gp = st->gp;
   struct st_fragment_program *old_fp = st->fp;

   struct gl_program *new_vp = ctx->VertexProgram._Current;
   struct gl_program *new_tcp = ctx->TessCtrlProgram._Current;
   struct gl_program *new_tep = ctx->TessEvalProgram._Current;
   struct gl_program *new_gp = ctx->GeometryProgram._Current;
   struct gl_program *new_fp = ctx->FragmentProgram._Current;
   uint64_t dirty = 0;
   unsigned num_viewports = 1;

   /* Flag states used by both new and old shaders to unbind shader resources
    * properly when transitioning to shaders that don't use them.
    */
   if (unlikely(new_vp != &old_vp->Base)) {
      if (old_vp)
         dirty |= old_vp->affected_states;
      if (new_vp)
         dirty |= ST_NEW_VERTEX_PROGRAM(st, st_vertex_program(new_vp));
   }

   if (unlikely(new_tcp != &old_tcp->Base)) {
      if (old_tcp)
         dirty |= old_tcp->affected_states;
      if (new_tcp)
         dirty |= st_common_program(new_tcp)->affected_states;
   }

   if (unlikely(new_tep != &old_tep->Base)) {
      if (old_tep)
         dirty |= old_tep->affected_states;
      if (new_tep)
         dirty |= st_common_program(new_tep)->affected_states;
   }

   if (unlikely(new_gp != &old_gp->Base)) {
      if (old_gp)
         dirty |= old_gp->affected_states;
      if (new_gp)
         dirty |= st_common_program(new_gp)->affected_states;
   }

   if (unlikely(new_fp != &old_fp->Base)) {
      if (old_fp)
         dirty |= old_fp->affected_states;
      if (new_fp)
         dirty |= st_fragment_program(new_fp)->affected_states;
   }

   /* Find out the number of viewports. This determines how many scissors
    * and viewport states we need to update.
    */
   struct gl_program *last_prim_shader = new_gp ? new_gp :
                                         new_tep ? new_tep : new_vp;
   if (last_prim_shader &&
       last_prim_shader->info.outputs_written & VARYING_BIT_VIEWPORT)
      num_viewports = ctx->Const.MaxViewports;

   if (st->state.num_viewports != num_viewports) {
      st->state.num_viewports = num_viewports;
      dirty |= ST_NEW_VIEWPORT;

      if (ctx->Scissor.EnableFlags & u_bit_consecutive(0, num_viewports))
         dirty |= ST_NEW_SCISSOR;
   }

   st->dirty |= dirty;
}

static void check_attrib_edgeflag(struct st_context *st)
{
   const struct gl_vertex_array **arrays = st->ctx->Array._DrawArrays;
   GLboolean vertdata_edgeflags, edgeflag_culls_prims, edgeflags_enabled;
   struct gl_program *vp = st->ctx->VertexProgram._Current;

   if (!arrays)
      return;

   edgeflags_enabled = st->ctx->Polygon.FrontMode != GL_FILL ||
                       st->ctx->Polygon.BackMode != GL_FILL;

   vertdata_edgeflags = edgeflags_enabled &&
                        arrays[VERT_ATTRIB_EDGEFLAG]->StrideB != 0;
   if (vertdata_edgeflags != st->vertdata_edgeflags) {
      st->vertdata_edgeflags = vertdata_edgeflags;
      if (vp)
         st->dirty |= ST_NEW_VERTEX_PROGRAM(st, st_vertex_program(vp));
   }

   edgeflag_culls_prims = edgeflags_enabled && !vertdata_edgeflags &&
                          !st->ctx->Current.Attrib[VERT_ATTRIB_EDGEFLAG][0];
   if (edgeflag_culls_prims != st->edgeflag_culls_prims) {
      st->edgeflag_culls_prims = edgeflag_culls_prims;
      st->dirty |= ST_NEW_RASTERIZER;
   }
}


/***********************************************************************
 * Update all derived state:
 */

void st_validate_state( struct st_context *st, enum st_pipeline pipeline )
{
   struct gl_context *ctx = st->ctx;
   uint64_t dirty, pipeline_mask;
   uint32_t dirty_lo, dirty_hi;

   /* Get Mesa driver state.
    *
    * Inactive states are shader states not used by shaders at the moment.
    */
   st->dirty |= ctx->NewDriverState & st->active_states & ST_ALL_STATES_MASK;
   ctx->NewDriverState = 0;

   /* Get pipeline state. */
   switch (pipeline) {
   case ST_PIPELINE_RENDER:
      if (st->ctx->API == API_OPENGL_COMPAT)
         check_attrib_edgeflag(st);

      if (st->gfx_shaders_may_be_dirty) {
         check_program_state(st);
         st->gfx_shaders_may_be_dirty = false;
      }

      st_manager_validate_framebuffers(st);

      pipeline_mask = ST_PIPELINE_RENDER_STATE_MASK;
      break;

   case ST_PIPELINE_CLEAR:
      st_manager_validate_framebuffers(st);
      pipeline_mask = ST_PIPELINE_CLEAR_STATE_MASK;
      break;

   case ST_PIPELINE_UPDATE_FRAMEBUFFER:
      st_manager_validate_framebuffers(st);
      pipeline_mask = ST_PIPELINE_UPDATE_FB_STATE_MASK;
      break;

   case ST_PIPELINE_COMPUTE: {
      struct st_compute_program *old_cp = st->cp;
      struct gl_program *new_cp = ctx->ComputeProgram._Current;

      if (new_cp != &old_cp->Base) {
         if (old_cp)
            st->dirty |= old_cp->affected_states;
         assert(new_cp);
         st->dirty |= st_compute_program(new_cp)->affected_states;
      }

      st->compute_shader_may_be_dirty = false;

      /*
       * We add the ST_NEW_FB_STATE bit here as well, because glBindFramebuffer
       * acts as a barrier that breaks feedback loops between the framebuffer
       * and textures bound to the framebuffer, even when those textures are
       * accessed by compute shaders; so we must inform the driver of new
       * framebuffer state.
       */
      pipeline_mask = ST_PIPELINE_COMPUTE_STATE_MASK | ST_NEW_FB_STATE;
      break;
   }

   default:
      unreachable("Invalid pipeline specified");
   }

   dirty = st->dirty & pipeline_mask;
   if (!dirty)
      return;

   dirty_lo = dirty;
   dirty_hi = dirty >> 32;

   /* Update states.
    *
    * Don't use u_bit_scan64, it may be slower on 32-bit.
    */
   while (dirty_lo)
      update_functions[u_bit_scan(&dirty_lo)](st);
   while (dirty_hi)
      update_functions[32 + u_bit_scan(&dirty_hi)](st);

   /* Clear the render or compute state bits. */
   st->dirty &= ~pipeline_mask;
}
