/*
 * Mesa 3-D graphics library
 *
 * Copyright (C) 1999-2005  Brian Paul   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.
 *
 * Authors:
 *    Keith Whitwell <keithw@vmware.com>
 */

#include "main/mtypes.h"
#include "main/bufferobj.h"
#include "math/m_eval.h"
#include "vbo.h"
#include "vbo_context.h"


static GLuint
check_size(const GLfloat *attr)
{
   if (attr[3] != 1.0F)
      return 4;
   if (attr[2] != 0.0F)
      return 3;
   if (attr[1] != 0.0F)
      return 2;
   return 1;
}


/**
 * Helper for initializing a vertex array.
 */
static void
init_array(struct gl_context *ctx, struct gl_vertex_array *cl,
           unsigned size, const void *pointer)
{
   memset(cl, 0, sizeof(*cl));

   cl->Size = size;
   cl->Type = GL_FLOAT;
   cl->Format = GL_RGBA;
   cl->StrideB = 0;
   cl->_ElementSize = cl->Size * sizeof(GLfloat);
   cl->Ptr = pointer;

   _mesa_reference_buffer_object(ctx, &cl->BufferObj,
                                 ctx->Shared->NullBufferObj);
}


/**
 * Set up the vbo->currval arrays to point at the context's current
 * vertex attributes (with strides = 0).
 */
static void
init_legacy_currval(struct gl_context *ctx)
{
   struct vbo_context *vbo = vbo_context(ctx);
   GLuint i;

   /* Set up a constant (StrideB == 0) array for each current
    * attribute:
    */
   for (i = 0; i < VERT_ATTRIB_FF_MAX; i++) {
      struct gl_vertex_array *cl = &vbo->currval[VERT_ATTRIB_FF(i)];

      init_array(ctx, cl,
                 check_size(ctx->Current.Attrib[i]),
                 ctx->Current.Attrib[i]);
   }
}


static void
init_generic_currval(struct gl_context *ctx)
{
   struct vbo_context *vbo = vbo_context(ctx);
   GLuint i;

   for (i = 0; i < VERT_ATTRIB_GENERIC_MAX; i++) {
      struct gl_vertex_array *cl = &vbo->currval[VBO_ATTRIB_GENERIC0 + i];

      init_array(ctx, cl, 1, ctx->Current.Attrib[VERT_ATTRIB_GENERIC0 + i]);
   }
}


static void
init_mat_currval(struct gl_context *ctx)
{
   struct vbo_context *vbo = vbo_context(ctx);
   GLuint i;

   /* Set up a constant (StrideB == 0) array for each current
    * attribute:
    */
   for (i = 0; i < MAT_ATTRIB_MAX; i++) {
      struct gl_vertex_array *cl =
         &vbo->currval[VBO_ATTRIB_MAT_FRONT_AMBIENT + i];
      unsigned size;

      /* Size is fixed for the material attributes, for others will
       * be determined at runtime:
       */
      switch (i) {
      case MAT_ATTRIB_FRONT_SHININESS:
      case MAT_ATTRIB_BACK_SHININESS:
         size = 1;
         break;
      case MAT_ATTRIB_FRONT_INDEXES:
      case MAT_ATTRIB_BACK_INDEXES:
         size = 3;
         break;
      default:
         size = 4;
         break;
      }

      init_array(ctx, cl, size, ctx->Light.Material.Attrib[i]);
   }
}

static void
vbo_draw_indirect_prims(struct gl_context *ctx,
                        GLuint mode,
                        struct gl_buffer_object *indirect_data,
                        GLsizeiptr indirect_offset,
                        unsigned draw_count,
                        unsigned stride,
                        struct gl_buffer_object *indirect_params,
                        GLsizeiptr indirect_params_offset,
                        const struct _mesa_index_buffer *ib)
{
   struct vbo_context *vbo = vbo_context(ctx);
   struct _mesa_prim *prim;
   GLsizei i;

   prim = calloc(draw_count, sizeof(*prim));
   if (prim == NULL) {
      _mesa_error(ctx, GL_OUT_OF_MEMORY, "gl%sDraw%sIndirect%s",
                  (draw_count > 1) ? "Multi" : "",
                  ib ? "Elements" : "Arrays",
                  indirect_params ? "CountARB" : "");
      return;
   }

   prim[0].begin = 1;
   prim[draw_count - 1].end = 1;
   for (i = 0; i < draw_count; ++i, indirect_offset += stride) {
      prim[i].mode = mode;
      prim[i].indexed = !!ib;
      prim[i].indirect_offset = indirect_offset;
      prim[i].is_indirect = 1;
      prim[i].draw_id = i;
   }

   vbo->draw_prims(ctx, prim, draw_count,
                   ib, false, 0, ~0,
                   NULL, 0,
                   ctx->DrawIndirectBuffer);

   free(prim);
}


GLboolean
_vbo_CreateContext(struct gl_context *ctx)
{
   struct vbo_context *vbo = CALLOC_STRUCT(vbo_context);

   ctx->vbo_context = vbo;

   /* Initialize the arrayelt helper
    */
   if (!ctx->aelt_context &&
       !_ae_create_context(ctx)) {
      return GL_FALSE;
   }

   init_legacy_currval(ctx);
   init_generic_currval(ctx);
   init_mat_currval(ctx);
   vbo_set_indirect_draw_func(ctx, vbo_draw_indirect_prims);

   /* Build mappings from VERT_ATTRIB -> VBO_ATTRIB depending on type
    * of vertex program active.
    */
   {
      GLuint i;

      /* make sure all VBO_ATTRIB_ values can fit in an unsigned byte */
      STATIC_ASSERT(VBO_ATTRIB_MAX <= 255);

      /* identity mapping */
      for (i = 0; i < ARRAY_SIZE(vbo->map_vp_none); i++)
         vbo->map_vp_none[i] = i;
      /* map material attribs to generic slots */
      for (i = 0; i < MAT_ATTRIB_MAX; i++)
         vbo->map_vp_none[VERT_ATTRIB_GENERIC(i)]
            = VBO_ATTRIB_MAT_FRONT_AMBIENT + i;

      for (i = 0; i < ARRAY_SIZE(vbo->map_vp_arb); i++)
         vbo->map_vp_arb[i] = i;
   }


   /* Hook our functions into exec and compile dispatch tables.  These
    * will pretty much be permanently installed, which means that the
    * vtxfmt mechanism can be removed now.
    */
   vbo_exec_init(ctx);
   if (ctx->API == API_OPENGL_COMPAT)
      vbo_save_init(ctx);

   _math_init_eval();

   return GL_TRUE;
}


void
_vbo_DestroyContext(struct gl_context *ctx)
{
   struct vbo_context *vbo = vbo_context(ctx);

   if (ctx->aelt_context) {
      _ae_destroy_context(ctx);
      ctx->aelt_context = NULL;
   }

   if (vbo) {
      GLuint i;

      for (i = 0; i < VBO_ATTRIB_MAX; i++) {
         _mesa_reference_buffer_object(ctx, &vbo->currval[i].BufferObj, NULL);
      }

      vbo_exec_destroy(ctx);
      if (ctx->API == API_OPENGL_COMPAT)
         vbo_save_destroy(ctx);
      free(vbo);
      ctx->vbo_context = NULL;
   }
}


void
vbo_set_draw_func(struct gl_context *ctx, vbo_draw_func func)
{
   struct vbo_context *vbo = vbo_context(ctx);
   vbo->draw_prims = func;
}


void
vbo_set_indirect_draw_func(struct gl_context *ctx,
                           vbo_indirect_draw_func func)
{
   struct vbo_context *vbo = vbo_context(ctx);
   vbo->draw_indirect_prims = func;
}