/*
 * Mesa 3-D graphics library
 *
 * Copyright (C) 1999-2008  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.
 */

/* Author:
 *    Keith Whitwell <keithw@vmware.com>
 */

#include "main/glheader.h"
#include "main/bufferobj.h"
#include "main/context.h"
#include "main/imports.h"
#include "main/mtypes.h"
#include "main/macros.h"
#include "main/light.h"
#include "main/state.h"
#include "util/bitscan.h"

#include "vbo_context.h"


/**
 * After playback, copy everything but the position from the
 * last vertex to the saved state
 */
static void
playback_copy_to_current(struct gl_context *ctx,
                         const struct vbo_save_vertex_list *node)
{
   struct vbo_context *vbo = vbo_context(ctx);
   fi_type vertex[VBO_ATTRIB_MAX * 4];
   fi_type *data;
   GLbitfield64 mask;

   if (node->current_size == 0)
      return;

   if (node->current_data) {
      data = node->current_data;
   }
   else {
      /* Position of last vertex */
      const GLuint pos = node->vertex_count > 0 ? node->vertex_count - 1 : 0;
      /* Offset to last vertex in the vertex buffer */
      const GLuint offset = node->buffer_offset
         + pos * node->vertex_size * sizeof(GLfloat);

      data = vertex;

      ctx->Driver.GetBufferSubData(ctx, offset,
                                   node->vertex_size * sizeof(GLfloat),
                                   data, node->vertex_store->bufferobj);

      data += node->attrsz[0]; /* skip vertex position */
   }

   mask = node->enabled & (~BITFIELD64_BIT(VBO_ATTRIB_POS));
   while (mask) {
      const int i = u_bit_scan64(&mask);
      fi_type *current = (fi_type *)vbo->currval[i].Ptr;
      fi_type tmp[4];
      assert(node->attrsz[i]);

      COPY_CLEAN_4V_TYPE_AS_UNION(tmp,
                                  node->attrsz[i],
                                  data,
                                  node->attrtype[i]);

      if (node->attrtype[i] != vbo->currval[i].Type ||
          memcmp(current, tmp, 4 * sizeof(GLfloat)) != 0) {
         memcpy(current, tmp, 4 * sizeof(GLfloat));

         vbo->currval[i].Size = node->attrsz[i];
         vbo->currval[i]._ElementSize = vbo->currval[i].Size * sizeof(GLfloat);
         vbo->currval[i].Type = node->attrtype[i];
         vbo->currval[i].Integer =
            vbo_attrtype_to_integer_flag(node->attrtype[i]);

         if (i >= VBO_ATTRIB_FIRST_MATERIAL &&
             i <= VBO_ATTRIB_LAST_MATERIAL)
            ctx->NewState |= _NEW_LIGHT;

         ctx->NewState |= _NEW_CURRENT_ATTRIB;
      }

      data += node->attrsz[i];
   }

   /* Colormaterial -- this kindof sucks.
    */
   if (ctx->Light.ColorMaterialEnabled) {
      _mesa_update_color_material(ctx, ctx->Current.Attrib[VBO_ATTRIB_COLOR0]);
   }

   /* CurrentExecPrimitive
    */
   if (node->prim_count) {
      const struct _mesa_prim *prim = &node->prims[node->prim_count - 1];
      if (prim->end)
         ctx->Driver.CurrentExecPrimitive = PRIM_OUTSIDE_BEGIN_END;
      else
         ctx->Driver.CurrentExecPrimitive = prim->mode;
   }
}



/**
 * Treat the vertex storage as a VBO, define vertex arrays pointing
 * into it:
 */
static void
bind_vertex_list(struct gl_context *ctx,
                 const struct vbo_save_vertex_list *node)
{
   struct vbo_context *vbo = vbo_context(ctx);
   struct vbo_save_context *save = &vbo->save;
   struct gl_vertex_array *arrays = save->arrays;
   GLuint buffer_offset = node->buffer_offset;
   const GLubyte *map;
   GLuint attr;
   GLubyte node_attrsz[VBO_ATTRIB_MAX];  /* copy of node->attrsz[] */
   GLenum node_attrtype[VBO_ATTRIB_MAX];  /* copy of node->attrtype[] */
   GLbitfield varying_inputs = 0x0;

   memcpy(node_attrsz, node->attrsz, sizeof(node->attrsz));
   memcpy(node_attrtype, node->attrtype, sizeof(node->attrtype));

   if (aligned_vertex_buffer_offset(node)) {
      /* The vertex size is an exact multiple of the buffer offset.
       * This means that we can use zero-based vertex attribute pointers
       * and specify the start of the primitive with the _mesa_prim::start
       * field.  This results in issuing several draw calls with identical
       * vertex attribute information.  This can result in fewer state
       * changes in drivers.  In particular, the Gallium CSO module will
       * filter out redundant vertex buffer changes.
       */
      buffer_offset = 0;
   }

   /* Install the default (ie Current) attributes first */
   for (attr = 0; attr < VERT_ATTRIB_FF_MAX; attr++) {
      save->inputs[attr] = &vbo->currval[VBO_ATTRIB_POS + attr];
   }

   /* Overlay other active attributes */
   switch (get_program_mode(ctx)) {
   case VP_NONE:
      for (attr = 0; attr < MAT_ATTRIB_MAX; attr++) {
         save->inputs[VERT_ATTRIB_GENERIC(attr)] =
            &vbo->currval[VBO_ATTRIB_MAT_FRONT_AMBIENT+attr];
      }
      map = vbo->map_vp_none;
      break;
   case VP_ARB:
      for (attr = 0; attr < VERT_ATTRIB_GENERIC_MAX; attr++) {
         save->inputs[VERT_ATTRIB_GENERIC(attr)] =
            &vbo->currval[VBO_ATTRIB_GENERIC0+attr];
      }
      map = vbo->map_vp_arb;

      /* check if VERT_ATTRIB_POS is not read but VERT_BIT_GENERIC0 is read.
       * In that case we effectively need to route the data from
       * glVertexAttrib(0, val) calls to feed into the GENERIC0 input.
       */
      const GLbitfield64 inputs_read =
         ctx->VertexProgram._Current->info.inputs_read;
      if ((inputs_read & VERT_BIT_POS) == 0 &&
          (inputs_read & VERT_BIT_GENERIC0)) {
         save->inputs[VERT_ATTRIB_GENERIC0] = save->inputs[0];
         node_attrsz[VERT_ATTRIB_GENERIC0] = node_attrsz[0];
         node_attrtype[VERT_ATTRIB_GENERIC0] = node_attrtype[0];
         node_attrsz[0] = 0;
      }
      break;
   default:
      assert(0);
   }

   for (attr = 0; attr < VERT_ATTRIB_MAX; attr++) {
      const GLuint src = map[attr];

      if (node_attrsz[src]) {
         struct gl_vertex_array *array = &arrays[attr];

         /* override the default array set above */
         save->inputs[attr] = array;

         array->Ptr = (const GLubyte *) NULL + buffer_offset;
         array->Size = node_attrsz[src];
         array->StrideB = node->vertex_size * sizeof(GLfloat);
         array->Type = node_attrtype[src];
         array->Integer = vbo_attrtype_to_integer_flag(node_attrtype[src]);
         array->Format = GL_RGBA;
         array->_ElementSize = array->Size * sizeof(GLfloat);
         _mesa_reference_buffer_object(ctx,
                                       &array->BufferObj,
                                       node->vertex_store->bufferobj);

         assert(array->BufferObj->Name);

         buffer_offset += node_attrsz[src] * sizeof(GLfloat);
         varying_inputs |= VERT_BIT(attr);
      }
   }

   _mesa_set_varying_vp_inputs(ctx, varying_inputs);
   ctx->NewDriverState |= ctx->DriverFlags.NewArray;
}


static void
loopback_vertex_list(struct gl_context *ctx,
                     const struct vbo_save_vertex_list *list)
{
   const char *buffer =
      ctx->Driver.MapBufferRange(ctx, 0,
                                 list->vertex_store->bufferobj->Size,
                                 GL_MAP_READ_BIT, /* ? */
                                 list->vertex_store->bufferobj,
                                 MAP_INTERNAL);

   unsigned buffer_offset =
      aligned_vertex_buffer_offset(list) ? 0 : list->buffer_offset;

   vbo_loopback_vertex_list(ctx,
                            (const GLfloat *) (buffer + buffer_offset),
                            list->attrsz,
                            list->prims,
                            list->prim_count,
                            list->wrap_count,
                            list->vertex_size);

   ctx->Driver.UnmapBuffer(ctx, list->vertex_store->bufferobj,
                           MAP_INTERNAL);
}


/**
 * Execute the buffer and save copied verts.
 * This is called from the display list code when executing
 * a drawing command.
 */
void
vbo_save_playback_vertex_list(struct gl_context *ctx, void *data)
{
   const struct vbo_save_vertex_list *node =
      (const struct vbo_save_vertex_list *) data;
   struct vbo_save_context *save = &vbo_context(ctx)->save;
   GLboolean remap_vertex_store = GL_FALSE;

   if (save->vertex_store && save->vertex_store->buffer_map) {
      /* The vertex store is currently mapped but we're about to replay
       * a display list.  This can happen when a nested display list is
       * being build with GL_COMPILE_AND_EXECUTE.
       * We never want to have mapped vertex buffers when we're drawing.
       * Unmap the vertex store, execute the list, then remap the vertex
       * store.
       */
      vbo_save_unmap_vertex_store(ctx, save->vertex_store);
      remap_vertex_store = GL_TRUE;
   }

   FLUSH_CURRENT(ctx, 0);

   if (node->prim_count > 0) {

      if (_mesa_inside_begin_end(ctx) && node->prims[0].begin) {
         /* Error: we're about to begin a new primitive but we're already
          * inside a glBegin/End pair.
          */
         _mesa_error(ctx, GL_INVALID_OPERATION,
                     "draw operation inside glBegin/End");
         goto end;
      }
      else if (save->replay_flags) {
         /* Various degenerate cases: translate into immediate mode
          * calls rather than trying to execute in place.
          */
         loopback_vertex_list(ctx, node);

         goto end;
      }

      if (ctx->NewState)
         _mesa_update_state(ctx);

      /* XXX also need to check if shader enabled, but invalid */
      if ((ctx->VertexProgram.Enabled &&
           !_mesa_arb_vertex_program_enabled(ctx)) ||
          (ctx->FragmentProgram.Enabled &&
           !_mesa_arb_fragment_program_enabled(ctx))) {
         _mesa_error(ctx, GL_INVALID_OPERATION,
                     "glBegin (invalid vertex/fragment program)");
         return;
      }

      bind_vertex_list(ctx, node);

      vbo_draw_method(vbo_context(ctx), DRAW_DISPLAY_LIST);

      /* Again...
       */
      if (ctx->NewState)
         _mesa_update_state(ctx);

      if (node->vertex_count > 0) {
         GLuint min_index = node->start_vertex;
         GLuint max_index = min_index + node->vertex_count - 1;
         vbo_context(ctx)->draw_prims(ctx,
                                      node->prims,
                                      node->prim_count,
                                      NULL,
                                      GL_TRUE,
                                      min_index, max_index,
                                      NULL, 0, NULL);
      }
   }

   /* Copy to current?
    */
   playback_copy_to_current(ctx, node);

end:
   if (remap_vertex_store) {
      save->buffer_ptr = vbo_save_map_vertex_store(ctx, save->vertex_store);
   }
}