#include "stdafx.h"
#include "../rsx_methods.h"
#include "GLGSRender.h"
#include "Emu/state.h"

color_format rsx::internals::surface_color_format_to_gl(rsx::surface_color_format color_format)
{
	//color format
	switch (color_format)
	{
	case rsx::surface_color_format::r5g6b5:
		return{ ::gl::texture::type::ushort_5_6_5, ::gl::texture::format::rgb, false, 3, 2 };

	case rsx::surface_color_format::a8r8g8b8:
		return{ ::gl::texture::type::uint_8_8_8_8, ::gl::texture::format::bgra, false, 4, 1 };

	case rsx::surface_color_format::x8r8g8b8_o8r8g8b8:
		return{ ::gl::texture::type::uint_8_8_8_8, ::gl::texture::format::bgra, false, 4, 1,
		{ ::gl::texture::channel::one, ::gl::texture::channel::r, ::gl::texture::channel::g, ::gl::texture::channel::b } };

	case rsx::surface_color_format::w16z16y16x16:
		return{ ::gl::texture::type::f16, ::gl::texture::format::rgba, true, 4, 2 };

	case rsx::surface_color_format::w32z32y32x32:
		return{ ::gl::texture::type::f32, ::gl::texture::format::rgba, true, 4, 4 };

	case rsx::surface_color_format::b8:
	case rsx::surface_color_format::x1r5g5b5_o1r5g5b5:
	case rsx::surface_color_format::x1r5g5b5_z1r5g5b5:
	case rsx::surface_color_format::x8r8g8b8_z8r8g8b8:
	case rsx::surface_color_format::g8b8:
	case rsx::surface_color_format::x32:
	case rsx::surface_color_format::x8b8g8r8_o8b8g8r8:
	case rsx::surface_color_format::x8b8g8r8_z8b8g8r8:
	case rsx::surface_color_format::a8b8g8r8:
	default:
		LOG_ERROR(RSX, "Surface color buffer: Unsupported surface color format (0x%x)", color_format);
		return{ ::gl::texture::type::uint_8_8_8_8, ::gl::texture::format::bgra, false, 4, 1 };
	}
}

depth_format rsx::internals::surface_depth_format_to_gl(rsx::surface_depth_format depth_format)
{
	switch (depth_format)
	{
	case rsx::surface_depth_format::z16:
		return{ ::gl::texture::type::ushort, ::gl::texture::format::depth, ::gl::texture::internal_format::depth16 };

	default:
		LOG_ERROR(RSX, "Surface depth buffer: Unsupported surface depth format (0x%x)", depth_format);
	case rsx::surface_depth_format::z24s8:
		return{ ::gl::texture::type::uint_24_8, ::gl::texture::format::depth_stencil, ::gl::texture::internal_format::depth24_stencil8 };
	}
}

u8 rsx::internals::get_pixel_size(rsx::surface_depth_format format)
{
	switch (format)
	{
	case rsx::surface_depth_format::z16: return 2;
	case rsx::surface_depth_format::z24s8: return 4;
	}
	throw EXCEPTION("Unknow depth format");
}


void GLGSRender::init_buffers(bool skip_reading)
{
	u32 surface_format = rsx::method_registers[NV4097_SET_SURFACE_FORMAT];

	u32 clip_horizontal = rsx::method_registers[NV4097_SET_SURFACE_CLIP_HORIZONTAL];
	u32 clip_vertical = rsx::method_registers[NV4097_SET_SURFACE_CLIP_VERTICAL];


	set_viewport();

	if (draw_fbo && !m_rtts_dirty)
		return;
	m_rtts_dirty = false;

	m_rtts.prepare_render_target(nullptr, surface_format, clip_horizontal, clip_vertical, rsx::to_surface_target(rsx::method_registers[NV4097_SET_SURFACE_COLOR_TARGET]),
		get_color_surface_addresses(), get_zeta_surface_address());

	draw_fbo.recreate();

	for (int i = 0; i < rsx::limits::color_buffers_count; ++i)
	{
		if (std::get<0>(m_rtts.m_bound_render_targets[i]) != 0)
			__glcheck draw_fbo.color[i] = *std::get<1>(m_rtts.m_bound_render_targets[i]);
	}
	if (std::get<0>(m_rtts.m_bound_depth_stencil) != 0)
		__glcheck draw_fbo.depth = *std::get<1>(m_rtts.m_bound_depth_stencil);
	__glcheck draw_fbo.check();


	switch (rsx::to_surface_target(rsx::method_registers[NV4097_SET_SURFACE_COLOR_TARGET]))
	{
	case rsx::surface_target::none: break;

	case rsx::surface_target::surface_a:
		__glcheck draw_fbo.draw_buffer(draw_fbo.color[0]);
		break;

	case rsx::surface_target::surface_b:
		__glcheck draw_fbo.draw_buffer(draw_fbo.color[1]);
		break;

	case rsx::surface_target::surfaces_a_b:
		__glcheck draw_fbo.draw_buffers({ draw_fbo.color[0], draw_fbo.color[1] });
		break;

	case rsx::surface_target::surfaces_a_b_c:
		__glcheck draw_fbo.draw_buffers({ draw_fbo.color[0], draw_fbo.color[1], draw_fbo.color[2] });
		break;

	case rsx::surface_target::surfaces_a_b_c_d:
		__glcheck draw_fbo.draw_buffers({ draw_fbo.color[0], draw_fbo.color[1], draw_fbo.color[2], draw_fbo.color[3] });
		break;
	}
}

std::array<std::vector<gsl::byte>, 4> GLGSRender::copy_render_targets_to_memory()
{
	int clip_w = rsx::method_registers[NV4097_SET_SURFACE_CLIP_HORIZONTAL] >> 16;
	int clip_h = rsx::method_registers[NV4097_SET_SURFACE_CLIP_VERTICAL] >> 16;
	rsx::surface_info surface = {};
	surface.unpack(rsx::method_registers[NV4097_SET_SURFACE_FORMAT]);
	return m_rtts.get_render_targets_data(surface.color_format, clip_w, clip_h);
}

std::array<std::vector<gsl::byte>, 2> GLGSRender::copy_depth_stencil_buffer_to_memory()
{
	int clip_w = rsx::method_registers[NV4097_SET_SURFACE_CLIP_HORIZONTAL] >> 16;
	int clip_h = rsx::method_registers[NV4097_SET_SURFACE_CLIP_VERTICAL] >> 16;
	rsx::surface_info surface = {};
	surface.unpack(rsx::method_registers[NV4097_SET_SURFACE_FORMAT]);
	return m_rtts.get_depth_stencil_data(surface.depth_format, clip_w, clip_h);
}

void GLGSRender::read_buffers()
{
	if (!draw_fbo)
		return;

	glDisable(GL_STENCIL_TEST);

	if (rpcs3::state.config.rsx.opengl.read_color_buffers)
	{
		auto color_format = rsx::internals::surface_color_format_to_gl(m_surface.color_format);

		auto read_color_buffers = [&](int index, int count)
		{
			u32 width = rsx::method_registers[NV4097_SET_SURFACE_CLIP_HORIZONTAL] >> 16;
			u32 height = rsx::method_registers[NV4097_SET_SURFACE_CLIP_VERTICAL] >> 16;

			for (int i = index; i < index + count; ++i)
			{
				u32 offset = rsx::method_registers[rsx::internals::mr_color_offset[i]];
				u32 location = rsx::method_registers[rsx::internals::mr_color_dma[i]];
				u32 pitch = rsx::method_registers[rsx::internals::mr_color_pitch[i]];

				if (pitch <= 64)
					continue;

				rsx::tiled_region color_buffer = get_tiled_address(offset, location & 0xf);
				u32 texaddr = (u32)((u64)color_buffer.ptr - (u64)vm::base(0));

				bool success = m_gl_texture_cache.explicit_writeback((*std::get<1>(m_rtts.m_bound_render_targets[i])), texaddr, pitch);

				//Fall back to slower methods if the image could not be fetched from cache.
				if (!success)
				{
					if (!color_buffer.tile)
					{
						__glcheck std::get<1>(m_rtts.m_bound_render_targets[i])->copy_from(color_buffer.ptr, color_format.format, color_format.type);
					}
					else
					{
						u32 range = pitch * height;
						m_gl_texture_cache.remove_in_range(texaddr, range);

						std::unique_ptr<u8[]> buffer(new u8[pitch * height]);
						color_buffer.read(buffer.get(), width, height, pitch);

						__glcheck std::get<1>(m_rtts.m_bound_render_targets[i])->copy_from(buffer.get(), color_format.format, color_format.type);
					}
				}
			}
		};

		switch (rsx::to_surface_target(rsx::method_registers[NV4097_SET_SURFACE_COLOR_TARGET]))
		{
		case rsx::surface_target::none:
			break;

		case rsx::surface_target::surface_a:
			read_color_buffers(0, 1);
			break;

		case rsx::surface_target::surface_b:
			read_color_buffers(1, 1);
			break;

		case rsx::surface_target::surfaces_a_b:
			read_color_buffers(0, 2);
			break;

		case rsx::surface_target::surfaces_a_b_c:
			read_color_buffers(0, 3);
			break;

		case rsx::surface_target::surfaces_a_b_c_d:
			read_color_buffers(0, 4);
			break;
		}
	}

	if (rpcs3::state.config.rsx.opengl.read_depth_buffer)
	{
		//TODO: use pitch
		u32 pitch = rsx::method_registers[NV4097_SET_SURFACE_PITCH_Z];

		if (pitch <= 64)
			return;

		u32 depth_address = rsx::get_address(rsx::method_registers[NV4097_SET_SURFACE_ZETA_OFFSET], rsx::method_registers[NV4097_SET_CONTEXT_DMA_ZETA]);
		bool in_cache = m_gl_texture_cache.explicit_writeback((*std::get<1>(m_rtts.m_bound_depth_stencil)), depth_address, pitch);

		if (in_cache)
			return;

		//Read failed. Fall back to slow s/w path...

		auto depth_format = rsx::internals::surface_depth_format_to_gl(m_surface.depth_format);
		int pixel_size = rsx::internals::get_pixel_size(m_surface.depth_format);
		gl::buffer pbo_depth;

		__glcheck pbo_depth.create(m_surface.width * m_surface.height * pixel_size);
		__glcheck pbo_depth.map([&](GLubyte* pixels)
		{
			u32 depth_address = rsx::get_address(rsx::method_registers[NV4097_SET_SURFACE_ZETA_OFFSET], rsx::method_registers[NV4097_SET_CONTEXT_DMA_ZETA]);

			if (m_surface.depth_format == rsx::surface_depth_format::z16)
			{
				u16 *dst = (u16*)pixels;
				const be_t<u16>* src = vm::ps3::_ptr<u16>(depth_address);
				for (int i = 0, end = std::get<1>(m_rtts.m_bound_depth_stencil)->width() * std::get<1>(m_rtts.m_bound_depth_stencil)->height(); i < end; ++i)
				{
					dst[i] = src[i];
				}
			}
			else
			{
				u32 *dst = (u32*)pixels;
				const be_t<u32>* src = vm::ps3::_ptr<u32>(depth_address);
				for (int i = 0, end = std::get<1>(m_rtts.m_bound_depth_stencil)->width() * std::get<1>(m_rtts.m_bound_depth_stencil)->height(); i < end; ++i)
				{
					dst[i] = src[i];
				}
			}
		}, gl::buffer::access::write);

		__glcheck std::get<1>(m_rtts.m_bound_depth_stencil)->copy_from(pbo_depth, depth_format.format, depth_format.type);
	}
}

void GLGSRender::write_buffers()
{
	if (!draw_fbo)
		return;

	//TODO: Detect when the data is actually being used by cell and issue download command on-demand (mark as not present?)
	//Should also mark cached resources as dirty so that read buffers works out-of-the-box without modification

	if (rpcs3::state.config.rsx.opengl.write_color_buffers)
	{
		auto color_format = rsx::internals::surface_color_format_to_gl(m_surface.color_format);

		auto write_color_buffers = [&](int index, int count)
		{
			u32 width = rsx::method_registers[NV4097_SET_SURFACE_CLIP_HORIZONTAL] >> 16;
			u32 height = rsx::method_registers[NV4097_SET_SURFACE_CLIP_VERTICAL] >> 16;

			for (int i = index; i < index + count; ++i)
			{
				u32 offset = rsx::method_registers[rsx::internals::mr_color_offset[i]];
				u32 location = rsx::method_registers[rsx::internals::mr_color_dma[i]];
				u32 pitch = rsx::method_registers[rsx::internals::mr_color_pitch[i]];

				if (pitch <= 64)
					continue;

				rsx::tiled_region color_buffer = get_tiled_address(offset, location & 0xf);
				u32 texaddr = (u32)((u64)color_buffer.ptr - (u64)vm::base(0));
				u32 range = pitch * height;

				/**Even tiles are loaded as whole textures during read_buffers from testing.
				* Need further evaluation to determine correct behavior. Separate paths for both show no difference,
				* but using the GPU to perform the caching is many times faster.
				*/

				__glcheck m_gl_texture_cache.save_render_target(texaddr, range, (*std::get<1>(m_rtts.m_bound_render_targets[i])));
			}
		};

		switch (rsx::to_surface_target(rsx::method_registers[NV4097_SET_SURFACE_COLOR_TARGET]))
		{
		case rsx::surface_target::none:
			break;

		case rsx::surface_target::surface_a:
			write_color_buffers(0, 1);
			break;

		case rsx::surface_target::surface_b:
			write_color_buffers(1, 1);
			break;

		case rsx::surface_target::surfaces_a_b:
			write_color_buffers(0, 2);
			break;

		case rsx::surface_target::surfaces_a_b_c:
			write_color_buffers(0, 3);
			break;

		case rsx::surface_target::surfaces_a_b_c_d:
			write_color_buffers(0, 4);
			break;
		}
	}

	if (rpcs3::state.config.rsx.opengl.write_depth_buffer)
	{
		//TODO: use pitch
		u32 pitch = rsx::method_registers[NV4097_SET_SURFACE_PITCH_Z];

		if (pitch <= 64)
			return;

		auto depth_format = rsx::internals::surface_depth_format_to_gl(m_surface.depth_format);
		u32 depth_address = rsx::get_address(rsx::method_registers[NV4097_SET_SURFACE_ZETA_OFFSET], rsx::method_registers[NV4097_SET_CONTEXT_DMA_ZETA]);
		u32 range = std::get<1>(m_rtts.m_bound_depth_stencil)->width() * std::get<1>(m_rtts.m_bound_depth_stencil)->height() * 2;

		if (m_surface.depth_format != rsx::surface_depth_format::z16) range *= 2;

		m_gl_texture_cache.save_render_target(depth_address, range, (*std::get<1>(m_rtts.m_bound_depth_stencil)));
	}
}