/**************************************************************************
 * 
 * Copyright 2007 Tungsten Graphics, Inc., Cedar Park, Texas.
 * 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 TUNGSTEN GRAPHICS 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.
 * 
 **************************************************************************/
 /*
  * Authors:
  *   Keith Whitwell <keith@tungstengraphics.com>
  *   Brian Paul
  */


#include "main/imports.h"
#include "main/mtypes.h"
#include "shader/prog_print.h"
#include "shader/programopt.h"

#include "pipe/p_context.h"
#include "pipe/p_defines.h"
#include "pipe/p_shader_tokens.h"
#include "draw/draw_context.h"
#include "tgsi/tgsi_dump.h"

#include "st_debug.h"
#include "st_context.h"
#include "st_program.h"
#include "st_mesa_to_tgsi.h"
#include "cso_cache/cso_context.h"



/**
 * Clean out any old compilations:
 */
void
st_vp_release_varients( struct st_context *st,
                        struct st_vertex_program *stvp )
{
   struct st_vp_varient *vpv;

   for (vpv = stvp->varients; vpv; ) {
      struct st_vp_varient *next = vpv->next;

      if (vpv->driver_shader) 
         cso_delete_vertex_shader(st->cso_context, vpv->driver_shader);
      
      if (vpv->draw_shader)
         draw_delete_vertex_shader( st->draw, vpv->draw_shader );
      
      if (vpv->tgsi.tokens)
         st_free_tokens(vpv->tgsi.tokens);
      
      FREE( vpv );

      vpv = next;
   }

   stvp->varients = NULL;
}




/**
 * Translate a Mesa vertex shader into a TGSI shader.
 * \param outputMapping  to map vertex program output registers (VERT_RESULT_x)
 *       to TGSI output slots
 * \param tokensOut  destination for TGSI tokens
 * \return  pointer to cached pipe_shader object.
 */
void
st_prepare_vertex_program(struct st_context *st,
                            struct st_vertex_program *stvp)
{
   GLuint attr;

   stvp->num_inputs = 0;
   stvp->num_outputs = 0;

   if (stvp->Base.IsPositionInvariant)
      _mesa_insert_mvp_code(st->ctx, &stvp->Base);

   assert(stvp->Base.Base.NumInstructions > 1);

   /*
    * Determine number of inputs, the mappings between VERT_ATTRIB_x
    * and TGSI generic input indexes, plus input attrib semantic info.
    */
   for (attr = 0; attr < VERT_ATTRIB_MAX; attr++) {
      if (stvp->Base.Base.InputsRead & (1 << attr)) {
         stvp->input_to_index[attr] = stvp->num_inputs;
         stvp->index_to_input[stvp->num_inputs] = attr;
         stvp->num_inputs++;
      }
   }
   /* bit of a hack, presetup potentially unused edgeflag input */
   stvp->input_to_index[VERT_ATTRIB_EDGEFLAG] = stvp->num_inputs;
   stvp->index_to_input[stvp->num_inputs] = VERT_ATTRIB_EDGEFLAG;

   /* Compute mapping of vertex program outputs to slots.
    */
   for (attr = 0; attr < VERT_RESULT_MAX; attr++) {
      if ((stvp->Base.Base.OutputsWritten & (1 << attr)) == 0) {
         stvp->result_to_output[attr] = ~0;
      }
      else {
         unsigned slot = stvp->num_outputs++;

         stvp->result_to_output[attr] = slot;

         switch (attr) {
         case VERT_RESULT_HPOS:
            stvp->output_semantic_name[slot] = TGSI_SEMANTIC_POSITION;
            stvp->output_semantic_index[slot] = 0;
            break;
         case VERT_RESULT_COL0:
            stvp->output_semantic_name[slot] = TGSI_SEMANTIC_COLOR;
            stvp->output_semantic_index[slot] = 0;
            break;
         case VERT_RESULT_COL1:
            stvp->output_semantic_name[slot] = TGSI_SEMANTIC_COLOR;
            stvp->output_semantic_index[slot] = 1;
            break;
         case VERT_RESULT_BFC0:
            stvp->output_semantic_name[slot] = TGSI_SEMANTIC_BCOLOR;
            stvp->output_semantic_index[slot] = 0;
            break;
         case VERT_RESULT_BFC1:
            stvp->output_semantic_name[slot] = TGSI_SEMANTIC_BCOLOR;
            stvp->output_semantic_index[slot] = 1;
            break;
         case VERT_RESULT_FOGC:
            stvp->output_semantic_name[slot] = TGSI_SEMANTIC_FOG;
            stvp->output_semantic_index[slot] = 0;
            break;
         case VERT_RESULT_PSIZ:
            stvp->output_semantic_name[slot] = TGSI_SEMANTIC_PSIZE;
            stvp->output_semantic_index[slot] = 0;
            break;
         case VERT_RESULT_EDGE:
            assert(0);
            break;

         case VERT_RESULT_TEX0:
         case VERT_RESULT_TEX1:
         case VERT_RESULT_TEX2:
         case VERT_RESULT_TEX3:
         case VERT_RESULT_TEX4:
         case VERT_RESULT_TEX5:
         case VERT_RESULT_TEX6:
         case VERT_RESULT_TEX7:
            stvp->output_semantic_name[slot] = TGSI_SEMANTIC_GENERIC;
            stvp->output_semantic_index[slot] = attr - VERT_RESULT_TEX0;
            break;

         case VERT_RESULT_VAR0:
         default:
            assert(attr < VERT_RESULT_MAX);
            stvp->output_semantic_name[slot] = TGSI_SEMANTIC_GENERIC;
            stvp->output_semantic_index[slot] = (FRAG_ATTRIB_VAR0 - 
                                                FRAG_ATTRIB_TEX0 +
                                                attr - 
                                                VERT_RESULT_VAR0);
            break;
         }
      }
   }
   /* similar hack to above, presetup potentially unused edgeflag output */
   stvp->result_to_output[VERT_RESULT_EDGE] = stvp->num_outputs;
   stvp->output_semantic_name[stvp->num_outputs] = TGSI_SEMANTIC_EDGEFLAG;
   stvp->output_semantic_index[stvp->num_outputs] = 0;
}


struct st_vp_varient *
st_translate_vertex_program(struct st_context *st,
                            struct st_vertex_program *stvp,
                            const struct st_vp_varient_key *key)
{
   struct st_vp_varient *vpv = CALLOC_STRUCT(st_vp_varient);
   struct pipe_context *pipe = st->pipe;
   struct ureg_program *ureg;
   enum pipe_error error;
   unsigned num_outputs;

   ureg = ureg_create( TGSI_PROCESSOR_VERTEX );
   if (ureg == NULL) {
      FREE(vpv);
      return NULL;
   }

   vpv->num_inputs = stvp->num_inputs;
   num_outputs = stvp->num_outputs;
   if (key->passthrough_edgeflags) {
      vpv->num_inputs++;
      num_outputs++;
   }

   error = 
      st_translate_mesa_program(st->ctx,
                                TGSI_PROCESSOR_VERTEX,
                                ureg,
                                &stvp->Base.Base,
                                /* inputs */
                                vpv->num_inputs,
                                stvp->input_to_index,
                                NULL, /* input semantic name */
                                NULL, /* input semantic index */
                                NULL,
                                /* outputs */
                                num_outputs,
                                stvp->result_to_output,
                                stvp->output_semantic_name,
                                stvp->output_semantic_index,
                                key->passthrough_edgeflags );

   if (error)
      goto fail;

   vpv->tgsi.tokens = ureg_get_tokens( ureg, NULL );
   if (!vpv->tgsi.tokens)
      goto fail;

   ureg_destroy( ureg );

   vpv->driver_shader = pipe->create_vs_state(pipe, &vpv->tgsi);

   if ((ST_DEBUG & DEBUG_TGSI) && (ST_DEBUG & DEBUG_MESA)) {
      _mesa_print_program(&stvp->Base.Base);
      debug_printf("\n");
   }

   if (ST_DEBUG & DEBUG_TGSI) {
      tgsi_dump( vpv->tgsi.tokens, 0 );
      debug_printf("\n");
   }

   return vpv;

fail:
   debug_printf("%s: failed to translate Mesa program:\n", __FUNCTION__);
   _mesa_print_program(&stvp->Base.Base);
   debug_assert(0);

   ureg_destroy( ureg );
   return NULL;
}



/**
 * Translate a Mesa fragment shader into a TGSI shader.
 * \return  pointer to cached pipe_shader object.
 */
void
st_translate_fragment_program(struct st_context *st,
                              struct st_fragment_program *stfp )
{
   struct pipe_context *pipe = st->pipe;
   GLuint outputMapping[FRAG_RESULT_MAX];
   GLuint inputMapping[FRAG_ATTRIB_MAX];
   GLuint interpMode[PIPE_MAX_SHADER_INPUTS];  /* XXX size? */
   GLuint attr;
   enum pipe_error error;
   const GLbitfield inputsRead = stfp->Base.Base.InputsRead;
   struct ureg_program *ureg;

   ubyte input_semantic_name[PIPE_MAX_SHADER_INPUTS];
   ubyte input_semantic_index[PIPE_MAX_SHADER_INPUTS];
   uint fs_num_inputs = 0;

   ubyte fs_output_semantic_name[PIPE_MAX_SHADER_OUTPUTS];
   ubyte fs_output_semantic_index[PIPE_MAX_SHADER_OUTPUTS];
   uint fs_num_outputs = 0;

   /*
    * Convert Mesa program inputs to TGSI input register semantics.
    */
   for (attr = 0; attr < FRAG_ATTRIB_MAX; attr++) {
      if (inputsRead & (1 << attr)) {
         const GLuint slot = fs_num_inputs++;

         inputMapping[attr] = slot;

         switch (attr) {
         case FRAG_ATTRIB_WPOS:
            input_semantic_name[slot] = TGSI_SEMANTIC_POSITION;
            input_semantic_index[slot] = 0;
            interpMode[slot] = TGSI_INTERPOLATE_LINEAR;
            break;
         case FRAG_ATTRIB_COL0:
            input_semantic_name[slot] = TGSI_SEMANTIC_COLOR;
            input_semantic_index[slot] = 0;
            interpMode[slot] = TGSI_INTERPOLATE_LINEAR;
            break;
         case FRAG_ATTRIB_COL1:
            input_semantic_name[slot] = TGSI_SEMANTIC_COLOR;
            input_semantic_index[slot] = 1;
            interpMode[slot] = TGSI_INTERPOLATE_LINEAR;
            break;
         case FRAG_ATTRIB_FOGC:
            input_semantic_name[slot] = TGSI_SEMANTIC_FOG;
            input_semantic_index[slot] = 0;
            interpMode[slot] = TGSI_INTERPOLATE_PERSPECTIVE;
            break;
         case FRAG_ATTRIB_FACE:
            input_semantic_name[slot] = TGSI_SEMANTIC_FACE;
            input_semantic_index[slot] = 0;
            interpMode[slot] = TGSI_INTERPOLATE_CONSTANT;
            break;
         case FRAG_ATTRIB_PNTC:
            /* This is a hack.  We really need a new semantic label for
             * point coord.  The draw module needs to know which fragment
             * shader input is the point coord attribute so that it can set
             * up the right vertex attribute values.
             */
            input_semantic_name[slot] = TGSI_SEMANTIC_GENERIC;
            input_semantic_index[slot] = 0;
            interpMode[slot] = TGSI_INTERPOLATE_PERSPECTIVE;
            break;

            /* In most cases, there is nothing special about these
             * inputs, so adopt a convention to use the generic
             * semantic name and the mesa FRAG_ATTRIB_ number as the
             * index. 
             * 
             * All that is required is that the vertex shader labels
             * its own outputs similarly, and that the vertex shader
             * generates at least every output required by the
             * fragment shader plus fixed-function hardware (such as
             * BFC).
             * 
             * There is no requirement that semantic indexes start at
             * zero or be restricted to a particular range -- nobody
             * should be building tables based on semantic index.
             */
         case FRAG_ATTRIB_TEX0:
         case FRAG_ATTRIB_TEX1:
         case FRAG_ATTRIB_TEX2:
         case FRAG_ATTRIB_TEX3:
         case FRAG_ATTRIB_TEX4:
         case FRAG_ATTRIB_TEX5:
         case FRAG_ATTRIB_TEX6:
         case FRAG_ATTRIB_TEX7:
         case FRAG_ATTRIB_VAR0:
         default:
            /* Actually, let's try and zero-base this just for
             * readability of the generated TGSI.
             */
            assert(attr >= FRAG_ATTRIB_TEX0);
            input_semantic_index[slot] = (attr - FRAG_ATTRIB_TEX0);
            input_semantic_name[slot] = TGSI_SEMANTIC_GENERIC;
            interpMode[slot] = TGSI_INTERPOLATE_PERSPECTIVE;
            break;
         }
      }
      else {
	 inputMapping[attr] = -1;
      }
   }

   /*
    * Semantics and mapping for outputs
    */
   {
      uint numColors = 0;
      GLbitfield64 outputsWritten = stfp->Base.Base.OutputsWritten;

      /* if z is written, emit that first */
      if (outputsWritten & (1 << FRAG_RESULT_DEPTH)) {
         fs_output_semantic_name[fs_num_outputs] = TGSI_SEMANTIC_POSITION;
         fs_output_semantic_index[fs_num_outputs] = 0;
         outputMapping[FRAG_RESULT_DEPTH] = fs_num_outputs;
         fs_num_outputs++;
         outputsWritten &= ~(1 << FRAG_RESULT_DEPTH);
      }

      /* handle remaning outputs (color) */
      for (attr = 0; attr < FRAG_RESULT_MAX; attr++) {
         if (outputsWritten & (1 << attr)) {
            switch (attr) {
            case FRAG_RESULT_DEPTH:
               /* handled above */
               assert(0);
               break;
            default:
               assert(attr == FRAG_RESULT_COLOR ||
                      (FRAG_RESULT_DATA0 <= attr && attr < FRAG_RESULT_MAX));
               fs_output_semantic_name[fs_num_outputs] = TGSI_SEMANTIC_COLOR;
               fs_output_semantic_index[fs_num_outputs] = numColors;
               outputMapping[attr] = fs_num_outputs;
               numColors++;
               break;
            }

            fs_num_outputs++;
         }
      }
   }

   ureg = ureg_create( TGSI_PROCESSOR_FRAGMENT );
   if (ureg == NULL)
      return;


   error = 
      st_translate_mesa_program(st->ctx,
                                TGSI_PROCESSOR_FRAGMENT,
                                ureg,
                                &stfp->Base.Base,
                                /* inputs */
                                fs_num_inputs,
                                inputMapping,
                                input_semantic_name,
                                input_semantic_index,
                                interpMode,
                                /* outputs */
                                fs_num_outputs,
                                outputMapping,
                                fs_output_semantic_name,
                                fs_output_semantic_index, FALSE );

   stfp->tgsi.tokens = ureg_get_tokens( ureg, NULL );
   ureg_destroy( ureg );
   stfp->driver_shader = pipe->create_fs_state(pipe, &stfp->tgsi);

   if ((ST_DEBUG & DEBUG_TGSI) && (ST_DEBUG & DEBUG_MESA)) {
      _mesa_print_program(&stfp->Base.Base);
      debug_printf("\n");
   }

   if (ST_DEBUG & DEBUG_TGSI) {
      tgsi_dump( stfp->tgsi.tokens, 0/*TGSI_DUMP_VERBOSE*/ );
      debug_printf("\n");
   }
}


/**
 * Debug- print current shader text
 */
void
st_print_shaders(GLcontext *ctx)
{
   struct gl_shader_program *shProg = ctx->Shader.CurrentProgram;
   if (shProg) {
      GLuint i;
      for (i = 0; i < shProg->NumShaders; i++) {
         printf("GLSL shader %u of %u:\n", i, shProg->NumShaders);
         printf("%s\n", shProg->Shaders[i]->Source);
      }
   }
}
