/*
 * Copyright (C) 2016 Rob Clark <robclark@freedesktop.org>
 *
 * 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 (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 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:
 *    Rob Clark <robclark@freedesktop.org>
 */

#include "pipe/p_state.h"
#include "util/u_blend.h"
#include "util/u_string.h"
#include "util/u_memory.h"

#include "fd5_blend.h"
#include "fd5_context.h"
#include "fd5_format.h"

// XXX move somewhere common.. same across a3xx/a4xx/a5xx..
static enum a3xx_rb_blend_opcode
blend_func(unsigned func)
{
	switch (func) {
	case PIPE_BLEND_ADD:
		return BLEND_DST_PLUS_SRC;
	case PIPE_BLEND_MIN:
		return BLEND_MIN_DST_SRC;
	case PIPE_BLEND_MAX:
		return BLEND_MAX_DST_SRC;
	case PIPE_BLEND_SUBTRACT:
		return BLEND_SRC_MINUS_DST;
	case PIPE_BLEND_REVERSE_SUBTRACT:
		return BLEND_DST_MINUS_SRC;
	default:
		DBG("invalid blend func: %x", func);
		return 0;
	}
}

void *
fd5_blend_state_create(struct pipe_context *pctx,
		const struct pipe_blend_state *cso)
{
	struct fd5_blend_stateobj *so;
	enum a3xx_rop_code rop = ROP_COPY;
	bool reads_dest = false;
	unsigned i, mrt_blend = 0;

	if (cso->logicop_enable) {
		rop = cso->logicop_func;  /* maps 1:1 */
		reads_dest = util_logicop_reads_dest(cso->logicop_func);
	}

	so = CALLOC_STRUCT(fd5_blend_stateobj);
	if (!so)
		return NULL;

	so->base = *cso;

	so->lrz_write = true;  /* unless blend enabled for any MRT */

	for (i = 0; i < ARRAY_SIZE(so->rb_mrt); i++) {
		const struct pipe_rt_blend_state *rt;

		if (cso->independent_blend_enable)
			rt = &cso->rt[i];
		else
			rt = &cso->rt[0];

		so->rb_mrt[i].blend_control =
				A5XX_RB_MRT_BLEND_CONTROL_RGB_SRC_FACTOR(fd_blend_factor(rt->rgb_src_factor)) |
				A5XX_RB_MRT_BLEND_CONTROL_RGB_BLEND_OPCODE(blend_func(rt->rgb_func)) |
				A5XX_RB_MRT_BLEND_CONTROL_RGB_DEST_FACTOR(fd_blend_factor(rt->rgb_dst_factor)) |
				A5XX_RB_MRT_BLEND_CONTROL_ALPHA_SRC_FACTOR(fd_blend_factor(rt->alpha_src_factor)) |
				A5XX_RB_MRT_BLEND_CONTROL_ALPHA_BLEND_OPCODE(blend_func(rt->alpha_func)) |
				A5XX_RB_MRT_BLEND_CONTROL_ALPHA_DEST_FACTOR(fd_blend_factor(rt->alpha_dst_factor));

		so->rb_mrt[i].control =
				A5XX_RB_MRT_CONTROL_ROP_CODE(rop) |
				COND(cso->logicop_enable, A5XX_RB_MRT_CONTROL_ROP_ENABLE) |
				A5XX_RB_MRT_CONTROL_COMPONENT_ENABLE(rt->colormask);

		if (rt->blend_enable) {
			so->rb_mrt[i].control |=
//					A5XX_RB_MRT_CONTROL_READ_DEST_ENABLE |
					A5XX_RB_MRT_CONTROL_BLEND |
					A5XX_RB_MRT_CONTROL_BLEND2;
			mrt_blend |= (1 << i);
			so->lrz_write = false;
		}

		if (reads_dest) {
//			so->rb_mrt[i].control |= A5XX_RB_MRT_CONTROL_READ_DEST_ENABLE;
			mrt_blend |= (1 << i);
		}

//		if (cso->dither)
//			so->rb_mrt[i].buf_info |= A5XX_RB_MRT_BUF_INFO_DITHER_MODE(DITHER_ALWAYS);
	}

	so->rb_blend_cntl = A5XX_RB_BLEND_CNTL_ENABLE_BLEND(mrt_blend) |
		COND(cso->alpha_to_coverage, A5XX_RB_BLEND_CNTL_ALPHA_TO_COVERAGE) |
		COND(cso->independent_blend_enable, A5XX_RB_BLEND_CNTL_INDEPENDENT_BLEND);
	so->sp_blend_cntl = A5XX_SP_BLEND_CNTL_UNK8 |
		COND(cso->alpha_to_coverage, A5XX_SP_BLEND_CNTL_ALPHA_TO_COVERAGE) |
		COND(mrt_blend, A5XX_SP_BLEND_CNTL_ENABLED);

	return so;
}