/**************************************************************************
 * 
 * Copyright 2008 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.
 * 
 **************************************************************************/


#include "pipe/p_screen.h"
#include "pipe/p_context.h"
#include "pipe/p_shader_tokens.h"
#include "util/u_inlines.h"
#include "cso_cache/cso_context.h"
#include "util/u_math.h"
#include "util/u_memory.h"
#include "util/u_sampler.h"
#include "util/u_simple_shaders.h"
#include "trace/tr_public.h"

#include "st_device.h"
#include "st_winsys.h"


static void
st_device_really_destroy(struct st_device *st_dev) 
{
   if(st_dev->screen) {
      /* FIXME: Don't really destroy until we keep track of every single 
       * reference or we end up causing a segmentation fault every time 
       * python exits. */
#if 0
      st_dev->screen->destroy(st_dev->screen);
#endif
   }
   
   FREE(st_dev);
}


static void
st_device_reference(struct st_device **ptr, struct st_device *st_dev)
{
   struct st_device *old_dev = *ptr;

   if (pipe_reference(&(*ptr)->reference, &st_dev->reference))
      st_device_really_destroy(old_dev);
   *ptr = st_dev;
}


void
st_device_destroy(struct st_device *st_dev) 
{
   st_device_reference(&st_dev, NULL);
}


struct st_device *
st_device_create(boolean hardware)
{
   struct pipe_screen *screen;
   struct st_device *st_dev;

   if (hardware)
      screen = st_hardware_screen_create();
   else
      screen = st_software_screen_create("softpipe");

   screen = trace_screen_create(screen);
   if (!screen)
      goto no_screen;

   st_dev = CALLOC_STRUCT(st_device);
   if (!st_dev)
      goto no_device;
   
   pipe_reference_init(&st_dev->reference, 1);
   st_dev->screen = screen;
   
   return st_dev;

no_device:
   screen->destroy(screen);
no_screen:
   return NULL;
}


void
st_context_destroy(struct st_context *st_ctx) 
{
   unsigned i;
   
   if(st_ctx) {
      struct st_device *st_dev = st_ctx->st_dev;
      
      if(st_ctx->cso) {
         cso_delete_vertex_shader(st_ctx->cso, st_ctx->vs);
         cso_delete_fragment_shader(st_ctx->cso, st_ctx->fs);
         
         cso_destroy_context(st_ctx->cso);
      }
      
      if(st_ctx->pipe)
         st_ctx->pipe->destroy(st_ctx->pipe);
      
      for(i = 0; i < PIPE_MAX_SAMPLERS; ++i)
         pipe_sampler_view_reference(&st_ctx->fragment_sampler_views[i], NULL);
      for(i = 0; i < PIPE_MAX_VERTEX_SAMPLERS; ++i)
         pipe_sampler_view_reference(&st_ctx->vertex_sampler_views[i], NULL);
      pipe_resource_reference(&st_ctx->default_texture, NULL);

      FREE(st_ctx);
      
      st_device_reference(&st_dev, NULL);
   }
}


struct st_context *
st_context_create(struct st_device *st_dev) 
{
   struct st_context *st_ctx;
   
   st_ctx = CALLOC_STRUCT(st_context);
   if(!st_ctx)
      return NULL;
   
   st_device_reference(&st_ctx->st_dev, st_dev);
   
   st_ctx->pipe = st_dev->screen->context_create(st_dev->screen, NULL);
   if(!st_ctx->pipe) {
      st_context_destroy(st_ctx);
      return NULL;
   }

   st_ctx->cso = cso_create_context(st_ctx->pipe);
   if(!st_ctx->cso) {
      st_context_destroy(st_ctx);
      return NULL;
   }
   
   /* disabled blending/masking */
   {
      struct pipe_blend_state blend;
      memset(&blend, 0, sizeof(blend));
      blend.rt[0].rgb_src_factor = PIPE_BLENDFACTOR_ONE;
      blend.rt[0].alpha_src_factor = PIPE_BLENDFACTOR_ONE;
      blend.rt[0].rgb_dst_factor = PIPE_BLENDFACTOR_ZERO;
      blend.rt[0].alpha_dst_factor = PIPE_BLENDFACTOR_ZERO;
      blend.rt[0].colormask = PIPE_MASK_RGBA;
      cso_set_blend(st_ctx->cso, &blend);
   }

   /* no-op depth/stencil/alpha */
   {
      struct pipe_depth_stencil_alpha_state depthstencil;
      memset(&depthstencil, 0, sizeof(depthstencil));
      cso_set_depth_stencil_alpha(st_ctx->cso, &depthstencil);
   }

   /* rasterizer */
   {
      struct pipe_rasterizer_state rasterizer;
      memset(&rasterizer, 0, sizeof(rasterizer));
      rasterizer.cull_face = PIPE_FACE_NONE;
      cso_set_rasterizer(st_ctx->cso, &rasterizer);
   }

   /* clip */
   {
      struct pipe_clip_state clip;
      memset(&clip, 0, sizeof(clip));
      st_ctx->pipe->set_clip_state(st_ctx->pipe, &clip);
   }

   /* identity viewport */
   {
      struct pipe_viewport_state viewport;
      viewport.scale[0] = 1.0;
      viewport.scale[1] = 1.0;
      viewport.scale[2] = 1.0;
      viewport.scale[3] = 1.0;
      viewport.translate[0] = 0.0;
      viewport.translate[1] = 0.0;
      viewport.translate[2] = 0.0;
      viewport.translate[3] = 0.0;
      cso_set_viewport(st_ctx->cso, &viewport);
   }

   /* samplers */
   {
      struct pipe_sampler_state sampler;
      unsigned i;
      memset(&sampler, 0, sizeof(sampler));
      sampler.wrap_s = PIPE_TEX_WRAP_CLAMP_TO_EDGE;
      sampler.wrap_t = PIPE_TEX_WRAP_CLAMP_TO_EDGE;
      sampler.wrap_r = PIPE_TEX_WRAP_CLAMP_TO_EDGE;
      sampler.min_mip_filter = PIPE_TEX_MIPFILTER_NEAREST;
      sampler.min_img_filter = PIPE_TEX_MIPFILTER_NEAREST;
      sampler.mag_img_filter = PIPE_TEX_MIPFILTER_NEAREST;
      sampler.normalized_coords = 1;
      for (i = 0; i < PIPE_MAX_SAMPLERS; i++)
         cso_single_sampler(st_ctx->cso, i, &sampler);
      cso_single_sampler_done(st_ctx->cso);
   }

   /* default textures */
   {
      struct pipe_context *pipe = st_ctx->pipe;
      struct pipe_screen *screen = st_dev->screen;
      struct pipe_resource templat;
      struct pipe_sampler_view view_templ;
      struct pipe_sampler_view *view;
      unsigned i;

      memset( &templat, 0, sizeof( templat ) );
      templat.target = PIPE_TEXTURE_2D;
      templat.format = PIPE_FORMAT_B8G8R8A8_UNORM;
      templat.width0 = 1;
      templat.height0 = 1;
      templat.depth0 = 1;
      templat.array_size = 1;
      templat.last_level = 0;
      templat.bind = PIPE_BIND_SAMPLER_VIEW;
   
      st_ctx->default_texture = screen->resource_create( screen, &templat );
      if(st_ctx->default_texture) {
	 struct pipe_box box;
	 uint32_t zero = 0;
	 
	 u_box_origin_2d( 1, 1, &box );

	 pipe->transfer_inline_write(pipe,
				     st_ctx->default_texture,
				     0,
				     PIPE_TRANSFER_WRITE,
				     &box,
				     &zero,
				     sizeof zero,
				     0);
      }

      u_sampler_view_default_template(&view_templ,
                                      st_ctx->default_texture,
                                      st_ctx->default_texture->format);
      view = st_ctx->pipe->create_sampler_view(st_ctx->pipe,
                                               st_ctx->default_texture,
                                               &view_templ);

      for (i = 0; i < PIPE_MAX_SAMPLERS; i++)
         pipe_sampler_view_reference(&st_ctx->fragment_sampler_views[i], view);
      for (i = 0; i < PIPE_MAX_VERTEX_SAMPLERS; i++)
         pipe_sampler_view_reference(&st_ctx->vertex_sampler_views[i], view);

      st_ctx->pipe->set_fragment_sampler_views(st_ctx->pipe,
                                               PIPE_MAX_SAMPLERS,
                                               st_ctx->fragment_sampler_views);
      st_ctx->pipe->set_vertex_sampler_views(st_ctx->pipe,
                                             PIPE_MAX_VERTEX_SAMPLERS,
                                             st_ctx->vertex_sampler_views);

      pipe_sampler_view_reference(&view, NULL);
   }
   
   /* vertex shader */
   {
      const uint semantic_names[] = { TGSI_SEMANTIC_POSITION,
                                      TGSI_SEMANTIC_GENERIC };
      const uint semantic_indexes[] = { 0, 0 };
      st_ctx->vs = util_make_vertex_passthrough_shader(st_ctx->pipe, 
                                                       2, 
                                                       semantic_names,
                                                       semantic_indexes);
      cso_set_vertex_shader_handle(st_ctx->cso, st_ctx->vs);
   }

   /* fragment shader */
   {
      st_ctx->fs = util_make_fragment_passthrough_shader(st_ctx->pipe);
      cso_set_fragment_shader_handle(st_ctx->cso, st_ctx->fs);
   }

   return st_ctx;
}