/*
 * Copyright (C) 2017 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 "util/u_blitter.h"
#include "util/u_surface.h"

#include "freedreno_blitter.h"
#include "freedreno_context.h"
#include "freedreno_resource.h"
#include "freedreno_fence.h"

/* generic blit using u_blitter.. slightly modified version of util_blitter_blit
 * which also handles PIPE_BUFFER:
 */

static void
default_dst_texture(struct pipe_surface *dst_templ, struct pipe_resource *dst,
		unsigned dstlevel, unsigned dstz)
{
	memset(dst_templ, 0, sizeof(*dst_templ));
	dst_templ->u.tex.level = dstlevel;
	dst_templ->u.tex.first_layer = dstz;
	dst_templ->u.tex.last_layer = dstz;
}

static void
default_src_texture(struct pipe_sampler_view *src_templ,
		struct pipe_resource *src, unsigned srclevel)
{
	bool cube_as_2darray = src->screen->get_param(src->screen,
			PIPE_CAP_SAMPLER_VIEW_TARGET);

	memset(src_templ, 0, sizeof(*src_templ));

	if (cube_as_2darray && (src->target == PIPE_TEXTURE_CUBE ||
			src->target == PIPE_TEXTURE_CUBE_ARRAY))
		src_templ->target = PIPE_TEXTURE_2D_ARRAY;
	else
		src_templ->target = src->target;

	if (src->target  == PIPE_BUFFER) {
		src_templ->target = PIPE_TEXTURE_1D;
	}
	src_templ->u.tex.first_level = srclevel;
	src_templ->u.tex.last_level = srclevel;
	src_templ->u.tex.first_layer = 0;
	src_templ->u.tex.last_layer =
			src->target == PIPE_TEXTURE_3D ? u_minify(src->depth0, srclevel) - 1
					: (unsigned)(src->array_size - 1);
	src_templ->swizzle_r = PIPE_SWIZZLE_X;
	src_templ->swizzle_g = PIPE_SWIZZLE_Y;
	src_templ->swizzle_b = PIPE_SWIZZLE_Z;
	src_templ->swizzle_a = PIPE_SWIZZLE_W;
}

static void
fd_blitter_pipe_begin(struct fd_context *ctx, bool render_cond, bool discard,
		enum fd_render_stage stage)
{
	fd_fence_ref(&ctx->last_fence, NULL);

	util_blitter_save_fragment_constant_buffer_slot(ctx->blitter,
			ctx->constbuf[PIPE_SHADER_FRAGMENT].cb);
	util_blitter_save_vertex_buffer_slot(ctx->blitter, ctx->vtx.vertexbuf.vb);
	util_blitter_save_vertex_elements(ctx->blitter, ctx->vtx.vtx);
	util_blitter_save_vertex_shader(ctx->blitter, ctx->prog.vp);
	util_blitter_save_so_targets(ctx->blitter, ctx->streamout.num_targets,
			ctx->streamout.targets);
	util_blitter_save_rasterizer(ctx->blitter, ctx->rasterizer);
	util_blitter_save_viewport(ctx->blitter, &ctx->viewport);
	util_blitter_save_scissor(ctx->blitter, &ctx->scissor);
	util_blitter_save_fragment_shader(ctx->blitter, ctx->prog.fp);
	util_blitter_save_blend(ctx->blitter, ctx->blend);
	util_blitter_save_depth_stencil_alpha(ctx->blitter, ctx->zsa);
	util_blitter_save_stencil_ref(ctx->blitter, &ctx->stencil_ref);
	util_blitter_save_sample_mask(ctx->blitter, ctx->sample_mask);
	util_blitter_save_framebuffer(ctx->blitter, &ctx->framebuffer);
	util_blitter_save_fragment_sampler_states(ctx->blitter,
			ctx->tex[PIPE_SHADER_FRAGMENT].num_samplers,
			(void **)ctx->tex[PIPE_SHADER_FRAGMENT].samplers);
	util_blitter_save_fragment_sampler_views(ctx->blitter,
			ctx->tex[PIPE_SHADER_FRAGMENT].num_textures,
			ctx->tex[PIPE_SHADER_FRAGMENT].textures);
	if (!render_cond)
		util_blitter_save_render_condition(ctx->blitter,
			ctx->cond_query, ctx->cond_cond, ctx->cond_mode);

	if (ctx->batch)
		fd_batch_set_stage(ctx->batch, stage);

	ctx->in_blit = discard;
}

static void
fd_blitter_pipe_end(struct fd_context *ctx)
{
	if (ctx->batch)
		fd_batch_set_stage(ctx->batch, FD_STAGE_NULL);
	ctx->in_blit = false;
}

bool
fd_blitter_blit(struct fd_context *ctx, const struct pipe_blit_info *info)
{
	struct pipe_resource *dst = info->dst.resource;
	struct pipe_resource *src = info->src.resource;
	struct pipe_context *pipe = &ctx->base;
	struct pipe_surface *dst_view, dst_templ;
	struct pipe_sampler_view src_templ, *src_view;
	bool discard = false;

	if (!info->scissor_enable && !info->alpha_blend) {
		discard = util_texrange_covers_whole_level(info->dst.resource,
				info->dst.level, info->dst.box.x, info->dst.box.y,
				info->dst.box.z, info->dst.box.width,
				info->dst.box.height, info->dst.box.depth);
	}

	fd_blitter_pipe_begin(ctx, info->render_condition_enable, discard, FD_STAGE_BLIT);

	/* Initialize the surface. */
	default_dst_texture(&dst_templ, dst, info->dst.level,
			info->dst.box.z);
	dst_templ.format = info->dst.format;
	dst_view = pipe->create_surface(pipe, dst, &dst_templ);

	/* Initialize the sampler view. */
	default_src_texture(&src_templ, src, info->src.level);
	src_templ.format = info->src.format;
	src_view = pipe->create_sampler_view(pipe, src, &src_templ);

	/* Copy. */
	util_blitter_blit_generic(ctx->blitter, dst_view, &info->dst.box,
			src_view, &info->src.box, src->width0, src->height0,
			info->mask, info->filter,
			info->scissor_enable ? &info->scissor : NULL,
			info->alpha_blend);

	pipe_surface_reference(&dst_view, NULL);
	pipe_sampler_view_reference(&src_view, NULL);

	fd_blitter_pipe_end(ctx);

	/* The fallback blitter must never fail: */
	return true;
}

/* Generic clear implementation (partially) using u_blitter: */
void
fd_blitter_clear(struct pipe_context *pctx, unsigned buffers,
		const union pipe_color_union *color, double depth, unsigned stencil)
{
	struct fd_context *ctx = fd_context(pctx);
	struct pipe_framebuffer_state *pfb = &ctx->batch->framebuffer;
	struct blitter_context *blitter = ctx->blitter;

	fd_blitter_pipe_begin(ctx, false, true, FD_STAGE_CLEAR);

	util_blitter_common_clear_setup(blitter, pfb->width, pfb->height,
			buffers, NULL, NULL);

	struct pipe_stencil_ref sr = {
		.ref_value = { stencil & 0xff }
	};
	pctx->set_stencil_ref(pctx, &sr);

	struct pipe_constant_buffer cb = {
		.buffer_size = 16,
		.user_buffer = &color->ui,
	};
	pctx->set_constant_buffer(pctx, PIPE_SHADER_FRAGMENT, 0, &cb);

	if (!ctx->clear_rs_state) {
		const struct pipe_rasterizer_state tmpl = {
			.cull_face = PIPE_FACE_NONE,
			.half_pixel_center = 1,
			.bottom_edge_rule = 1,
			.flatshade = 1,
			.depth_clip_near = 1,
			.depth_clip_far = 1,
		};
		ctx->clear_rs_state = pctx->create_rasterizer_state(pctx, &tmpl);
	}
	pctx->bind_rasterizer_state(pctx, ctx->clear_rs_state);

	struct pipe_viewport_state vp = {
		.scale     = { 0.5f * pfb->width, -0.5f * pfb->height, depth },
		.translate = { 0.5f * pfb->width,  0.5f * pfb->height, 0.0f },
	};
	pctx->set_viewport_states(pctx, 0, 1, &vp);

	pctx->bind_vertex_elements_state(pctx, ctx->solid_vbuf_state.vtx);
	pctx->set_vertex_buffers(pctx, blitter->vb_slot, 1,
			&ctx->solid_vbuf_state.vertexbuf.vb[0]);
	pctx->set_stream_output_targets(pctx, 0, NULL, NULL);
	pctx->bind_vs_state(pctx, ctx->solid_prog.vp);
	pctx->bind_fs_state(pctx, ctx->solid_prog.fp);

	struct pipe_draw_info info = {
		.mode = PIPE_PRIM_MAX,    /* maps to DI_PT_RECTLIST */
		.count = 2,
		.max_index = 1,
		.instance_count = 1,
	};
	ctx->draw_vbo(ctx, &info, 0);

	util_blitter_restore_constant_buffer_state(blitter);
	util_blitter_restore_vertex_states(blitter);
	util_blitter_restore_fragment_states(blitter);
	util_blitter_restore_textures(blitter);
	util_blitter_restore_fb_state(blitter);
	util_blitter_restore_render_cond(blitter);
	util_blitter_unset_running_flag(blitter);

	fd_blitter_pipe_end(ctx);
}

/**
 * Optimal hardware path for blitting pixels.
 * Scaling, format conversion, up- and downsampling (resolve) are allowed.
 */
bool
fd_blit(struct pipe_context *pctx, const struct pipe_blit_info *blit_info)
{
	struct fd_context *ctx = fd_context(pctx);
	struct pipe_blit_info info = *blit_info;

	if (info.render_condition_enable && !fd_render_condition_check(pctx))
		return true;

	if (ctx->blit && ctx->blit(ctx, &info))
		return true;

	if (info.mask & PIPE_MASK_S) {
		DBG("cannot blit stencil, skipping");
		info.mask &= ~PIPE_MASK_S;
	}

	if (!util_blitter_is_blit_supported(ctx->blitter, &info)) {
		DBG("blit unsupported %s -> %s",
				util_format_short_name(info.src.resource->format),
				util_format_short_name(info.dst.resource->format));
		return false;
	}

	return fd_blitter_blit(ctx, &info);
}

/**
 * _copy_region using pipe (3d engine)
 */
static bool
fd_blitter_pipe_copy_region(struct fd_context *ctx,
		struct pipe_resource *dst,
		unsigned dst_level,
		unsigned dstx, unsigned dsty, unsigned dstz,
		struct pipe_resource *src,
		unsigned src_level,
		const struct pipe_box *src_box)
{
	/* not until we allow rendertargets to be buffers */
	if (dst->target == PIPE_BUFFER || src->target == PIPE_BUFFER)
		return false;

	if (!util_blitter_is_copy_supported(ctx->blitter, dst, src))
		return false;

	/* TODO we could discard if dst box covers dst level fully.. */
	fd_blitter_pipe_begin(ctx, false, false, FD_STAGE_BLIT);
	util_blitter_copy_texture(ctx->blitter,
			dst, dst_level, dstx, dsty, dstz,
			src, src_level, src_box);
	fd_blitter_pipe_end(ctx);

	return true;
}

/**
 * Copy a block of pixels from one resource to another.
 * The resource must be of the same format.
 */
void
fd_resource_copy_region(struct pipe_context *pctx,
		struct pipe_resource *dst,
		unsigned dst_level,
		unsigned dstx, unsigned dsty, unsigned dstz,
		struct pipe_resource *src,
		unsigned src_level,
		const struct pipe_box *src_box)
{
	struct fd_context *ctx = fd_context(pctx);

	if (ctx->blit) {
		struct pipe_blit_info info;

		memset(&info, 0, sizeof info);
		info.dst.resource = dst;
		info.dst.level = dst_level;
		info.dst.box.x = dstx;
		info.dst.box.y = dsty;
		info.dst.box.z = dstz;
		info.dst.box.width = src_box->width;
		info.dst.box.height = src_box->height;
		assert(info.dst.box.width >= 0);
		assert(info.dst.box.height >= 0);
		info.dst.box.depth = 1;
		info.dst.format = dst->format;
		info.src.resource = src;
		info.src.level = src_level;
		info.src.box = *src_box;
		info.src.format = src->format;
		info.mask = util_format_get_mask(src->format);
		info.filter = PIPE_TEX_FILTER_NEAREST;
		info.scissor_enable = 0;

		if (ctx->blit(ctx, &info))
			return;
	}

	/* TODO if we have 2d core, or other DMA engine that could be used
	 * for simple copies and reasonably easily synchronized with the 3d
	 * core, this is where we'd plug it in..
	 */

	/* try blit on 3d pipe: */
	if (fd_blitter_pipe_copy_region(ctx,
			dst, dst_level, dstx, dsty, dstz,
			src, src_level, src_box))
		return;

	/* else fallback to pure sw: */
	util_resource_copy_region(pctx,
			dst, dst_level, dstx, dsty, dstz,
			src, src_level, src_box);
}