#pragma once

#include "stdafx.h"

#include <exception>
#include <string>
#include <functional>
#include <vector>
#include <memory>
#include <thread>
#include <condition_variable>
#include <chrono>

#include "Utilities/mutex.h"
#include "Emu/System.h"
#include "GLRenderTargets.h"
#include "../Common/TextureUtils.h"
#include "../Common/texture_cache.h"
#include "../../Memory/vm.h"
#include "../rsx_utils.h"

class GLGSRender;

namespace gl
{
	extern GLenum get_sized_internal_format(u32);

	class cached_texture_section : public rsx::buffered_section
	{
	private:
		fence m_fence;
		u32 pbo_id = 0;
		u32 pbo_size = 0;

		u32 vram_texture = 0;

		bool copied = false;
		bool flushed = false;
		bool is_depth = false;

		u32 current_width = 0;
		u32 current_height = 0;
		u32 current_pitch = 0;
		u32 real_pitch = 0;

		texture::format format = texture::format::rgba;
		texture::type type = texture::type::ubyte;
		bool pack_unpack_swap_bytes = false;

		u8 get_pixel_size(texture::format fmt_, texture::type type_)
		{
			u8 size = 1;
			switch (type_)
			{
			case texture::type::ubyte:
			case texture::type::sbyte:
				break;
			case texture::type::ushort:
			case texture::type::sshort:
			case texture::type::f16:
				size = 2;
				break;
			case texture::type::ushort_5_6_5:
			case texture::type::ushort_5_6_5_rev:
			case texture::type::ushort_4_4_4_4:
			case texture::type::ushort_4_4_4_4_rev:
			case texture::type::ushort_5_5_5_1:
			case texture::type::ushort_1_5_5_5_rev:
				return 2;
			case texture::type::uint_8_8_8_8:
			case texture::type::uint_8_8_8_8_rev:
			case texture::type::uint_10_10_10_2:
			case texture::type::uint_2_10_10_10_rev:
			case texture::type::uint_24_8:
				return 4;
			case texture::type::f32:
			case texture::type::sint:
			case texture::type::uint:
				size = 4;
				break;
			}

			switch (fmt_)
			{
			case texture::format::red:
			case texture::format::r:
				break;
			case texture::format::rg:
				size *= 2;
				break;
			case texture::format::rgb:
			case texture::format::bgr:
				size *= 3;
				break;
			case texture::format::rgba:
			case texture::format::bgra:
				size *= 4;
				break;

			//Depth formats..
			case texture::format::depth:
				size = 2;
				break;
			case texture::format::depth_stencil:
				size = 4;
				break;
			default:
				LOG_ERROR(RSX, "Unsupported rtt format %d", (GLenum)fmt_);
				size = 4;
			}

			return size;
		}

		void init_buffer()
		{
			if (pbo_id)
			{
				glDeleteBuffers(1, &pbo_id);
				pbo_id = 0;
				pbo_size = 0;
			}

			glGenBuffers(1, &pbo_id);

			const u32 buffer_size = align(cpu_address_range, 4096);
			glBindBuffer(GL_PIXEL_PACK_BUFFER, pbo_id);
			glBufferStorage(GL_PIXEL_PACK_BUFFER, buffer_size, nullptr, GL_MAP_READ_BIT);

			pbo_size = buffer_size;
		}

	public:

		void reset(const u32 base, const u32 size, const bool flushable=false)
		{
			rsx::protection_policy policy = g_cfg.video.strict_rendering_mode ? rsx::protection_policy::protect_policy_full_range : rsx::protection_policy::protect_policy_one_page;
			rsx::buffered_section::reset(base, size, policy);

			if (flushable)
				init_buffer();
			
			flushed = false;
			copied = false;
			is_depth = false;

			vram_texture = 0;
		}
		
		void create(const u16 w, const u16 h, const u16 /*depth*/, const u16 /*mipmaps*/, void*,
				gl::texture* image, const u32 native_pitch, bool read_only,
				gl::texture::format gl_format, gl::texture::type gl_type, bool swap_bytes)
		{
			if (!read_only && pbo_id == 0)
				init_buffer();

			flushed = false;
			copied = false;
			is_depth = false;

			current_width = w;
			current_height = h;
			current_pitch = native_pitch;

			vram_texture = image->id();
			set_format(gl_format, gl_type, swap_bytes);
		}

		void create_read_only(const u32 id, const u32 width, const u32 height)
		{
			//Only to be used for ro memory, we dont care about most members, just dimensions and the vram texture handle
			current_width = width;
			current_height = height;
			vram_texture = id;

			current_pitch = 0;
			real_pitch = 0;
		}

		bool matches(const u32 rsx_address, const u32 rsx_size)
		{
			return rsx::buffered_section::matches(rsx_address, rsx_size);
		}

		bool matches(const u32 rsx_address, const u32 width, const u32 height, const u32 mipmaps)
		{
			if (cpu_address_base == rsx_address && !dirty)
			{
				//Mostly only used to debug; matches textures without checking dimensions
				if (width == 0 && height == 0)
					return true;

				return (current_width == width && current_height == height);
			}

			return false;
		}

		void set_dimensions(u32 width, u32 height, u32 pitch)
		{
			current_width = width;
			current_height = height;
			current_pitch = pitch;

			real_pitch = width * get_pixel_size(format, type);
		}

		void set_format(const texture::format gl_format, const texture::type gl_type, const bool swap_bytes)
		{
			format = gl_format;
			type = gl_type;
			pack_unpack_swap_bytes = swap_bytes;

			real_pitch = current_width * get_pixel_size(format, type);
		}

		void set_depth_flag(bool is_depth_fmt)
		{
			is_depth = is_depth_fmt;
		}

		void set_source(gl::texture &source)
		{
			vram_texture = source.id();
		}

		void copy_texture(bool=false)
		{
			if (!glIsTexture(vram_texture))
			{
				LOG_ERROR(RSX, "Attempted to download rtt texture, but texture handle was invalid! (0x%X)", vram_texture);
				return;
			}

			glPixelStorei(GL_PACK_SWAP_BYTES, pack_unpack_swap_bytes);
			glBindBuffer(GL_PIXEL_PACK_BUFFER, pbo_id);

			if (get_driver_caps().EXT_dsa_supported)
				glGetTextureImageEXT(vram_texture, GL_TEXTURE_2D, 0, (GLenum)format, (GLenum)type, nullptr);
			else
				glGetTextureImage(vram_texture, 0, (GLenum)format, (GLenum)type, pbo_size, nullptr);

			glBindBuffer(GL_PIXEL_PACK_BUFFER, 0);

			m_fence.reset();
			copied = true;
		}

		void fill_texture(gl::texture* tex)
		{
			if (!copied)
			{
				//LOG_WARNING(RSX, "Request to fill texture rejected because contents were not read");
				return;
			}

			u32 min_width = std::min((u32)tex->width(), current_width);
			u32 min_height = std::min((u32)tex->height(), current_height);

			tex->bind();
			glPixelStorei(GL_UNPACK_SWAP_BYTES, pack_unpack_swap_bytes);
			glBindBuffer(GL_PIXEL_UNPACK_BUFFER, pbo_id);
			glTexSubImage2D((GLenum)tex->get_target(), 0, 0, 0, min_width, min_height, (GLenum)format, (GLenum)type, nullptr);
			glBindBuffer(GL_PIXEL_UNPACK_BUFFER, 0);
		}

		bool flush()
		{
			if (!copied)
			{
				LOG_WARNING(RSX, "Cache miss at address 0x%X. This is gonna hurt...", cpu_address_base);
				copy_texture();

				if (!copied)
				{
					LOG_WARNING(RSX, "Nothing to copy; Setting section to readable and moving on...");
					protect(utils::protection::ro);
					return false;
				}
			}

			protect(utils::protection::rw);
			m_fence.wait_for_signal();
			flushed = true;

			glBindBuffer(GL_PIXEL_PACK_BUFFER, pbo_id);
			void *data = glMapBufferRange(GL_PIXEL_PACK_BUFFER, 0, pbo_size, GL_MAP_READ_BIT);
			u8 *dst = vm::ps3::_ptr<u8>(cpu_address_base);

			//throw if map failed since we'll segfault anyway
			verify(HERE), data != nullptr;

			if (real_pitch >= current_pitch)
			{
				memcpy(dst, data, cpu_address_range);
			}
			else
			{
				//TODO: Use compression hint from the gcm tile information
				//TODO: Fall back to bilinear filtering if samples > 2

				const u8 pixel_size = get_pixel_size(format, type);
				const u8 samples = current_pitch / real_pitch;
				rsx::scale_image_nearest(dst, const_cast<const void*>(data), current_width, current_height, current_pitch, real_pitch, pixel_size, samples);
			}

			glUnmapBuffer(GL_PIXEL_PACK_BUFFER);
			glBindBuffer(GL_PIXEL_PACK_BUFFER, 0);
			protect(utils::protection::ro);
			
			return true;
		}

		void destroy()
		{
			if (!locked && pbo_id == 0 && vram_texture == 0 && m_fence.is_empty())
				//Already destroyed
				return;

			if (locked)
				unprotect();

			if (pbo_id == 0)
			{
				//Read-only texture, destroy texture memory
				glDeleteTextures(1, &vram_texture);
				vram_texture = 0;
			}
			else
			{
				//Destroy pbo cache since vram texture is managed elsewhere
				glDeleteBuffers(1, &pbo_id);
				pbo_id = 0;
				pbo_size = 0;
			}

			m_fence.destroy();
		}
		
		texture::format get_format() const
		{
			return format;
		}
		
		bool exists() const
		{
			return vram_texture != 0;
		}
		
		bool is_flushable() const
		{
			return pbo_id != 0;
		}

		bool is_flushed() const
		{
			return flushed;
		}

		bool is_synchronized() const
		{
			return copied;
		}

		void set_flushed(const bool state)
		{
			flushed = state;
		}

		bool is_empty() const
		{
			return vram_texture == 0;
		}

		u32 get_raw_view() const
		{
			return vram_texture;
		}

		u32 get_raw_texture() const
		{
			return vram_texture;
		}

		u32 get_width() const
		{
			return current_width;
		}
		
		u32 get_height() const
		{
			return current_height;
		}

		bool is_depth_texture() const
		{
			return is_depth;
		}

		bool has_compatible_format(gl::texture* tex) const
		{
			GLenum fmt;
			glBindTexture(GL_TEXTURE_2D, vram_texture);
			glGetTexLevelParameteriv(GL_TEXTURE_2D, 0, GL_TEXTURE_INTERNAL_FORMAT, (GLint*)&fmt);

			if (auto as_rtt = dynamic_cast<gl::render_target*>(tex))
			{
				return (GLenum)as_rtt->get_compatible_internal_format() == fmt;
			}

			return (gl::texture::format)fmt == tex->get_internal_format();
		}
	};
		
	class texture_cache : public rsx::texture_cache<void*, cached_texture_section, u32, u32, gl::texture, gl::texture::format>
	{
	private:
	
		class blitter
		{
			fbo blit_src;
			fbo blit_dst;

		public:

			void init()
			{
				blit_src.create();
				blit_dst.create();
			}

			void destroy()
			{
				blit_dst.remove();
				blit_src.remove();
			}

			u32 scale_image(u32 src, u32 dst, const areai src_rect, const areai dst_rect, bool linear_interpolation, bool is_depth_copy)
			{
				s32 old_fbo = 0;
				glGetIntegerv(GL_FRAMEBUFFER_BINDING, &old_fbo);
				
				u32 dst_tex = dst;
				filter interp = linear_interpolation ? filter::linear : filter::nearest;

				GLenum attachment = is_depth_copy ? GL_DEPTH_ATTACHMENT : GL_COLOR_ATTACHMENT0;

				blit_src.bind();
				glFramebufferTexture2D(GL_FRAMEBUFFER, attachment, GL_TEXTURE_2D, src, 0);
				blit_src.check();

				blit_dst.bind();
				glFramebufferTexture2D(GL_FRAMEBUFFER, attachment, GL_TEXTURE_2D, dst_tex, 0);
				blit_dst.check();

				GLboolean scissor_test_enabled = glIsEnabled(GL_SCISSOR_TEST);
				if (scissor_test_enabled)
					glDisable(GL_SCISSOR_TEST);

				blit_src.blit(blit_dst, src_rect, dst_rect, is_depth_copy ? buffers::depth : buffers::color, interp);

				if (scissor_test_enabled)
					glEnable(GL_SCISSOR_TEST);

				glBindFramebuffer(GL_FRAMEBUFFER, old_fbo);
				return dst_tex;
			}
		};

	private:

		blitter m_hw_blitter;
		std::vector<u32> m_temporary_surfaces;

		cached_texture_section& create_texture(u32 id, u32 texaddr, u32 texsize, u32 w, u32 h)
		{
			cached_texture_section& tex = find_cached_texture(texaddr, texsize, true, w, h);
			tex.reset(texaddr, texsize, false);
			tex.create_read_only(id, w, h);
			read_only_range = tex.get_min_max(read_only_range);
			return tex;
		}

		void clear()
		{
			for (auto &address_range : m_cache)
			{
				auto &range_data = address_range.second;
				for (auto &tex : range_data.data)
				{
					tex.destroy();
				}

				range_data.data.resize(0);
			}

			clear_temporary_subresources();
			m_unreleased_texture_objects = 0;
		}
		
		void clear_temporary_subresources()
		{
			for (u32 &id : m_temporary_surfaces)
			{
				glDeleteTextures(1, &id);
			}

			m_temporary_surfaces.resize(0);
		}

		u32 create_temporary_subresource(u32 src_id, GLenum sized_internal_fmt, u16 x, u16 y, u16 width, u16 height)
		{
			u32 dst_id = 0;

			glGenTextures(1, &dst_id);
			glBindTexture(GL_TEXTURE_2D, dst_id);

			glTexStorage2D(GL_TEXTURE_2D, 1, sized_internal_fmt, width, height);
			glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
			glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);

			//Empty GL_ERROR
			glGetError();

			glCopyImageSubData(src_id, GL_TEXTURE_2D, 0, x, y, 0,
				dst_id, GL_TEXTURE_2D, 0, 0, 0, 0, width, height, 1);

			m_temporary_surfaces.push_back(dst_id);

			//Check for error
			if (GLenum err = glGetError())
			{
				LOG_WARNING(RSX, "Failed to copy image subresource with GL error 0x%X", err);
				return 0;
			}

			return dst_id;
		}
		
	protected:
		
		void free_texture_section(cached_texture_section& tex) override
		{
			tex.destroy();
		}

		u32 create_temporary_subresource_view(void*&, u32* src, u32 gcm_format, u16 x, u16 y, u16 w, u16 h) override
		{
			const GLenum ifmt = gl::get_sized_internal_format(gcm_format);
			return create_temporary_subresource(*src, ifmt, x, y, w, h);
		}

		u32 create_temporary_subresource_view(void*&, gl::texture* src, u32 gcm_format, u16 x, u16 y, u16 w, u16 h) override
		{
			if (auto as_rtt = dynamic_cast<gl::render_target*>(src))
			{
				return create_temporary_subresource(src->id(), (GLenum)as_rtt->get_compatible_internal_format(), x, y, w, h);
			}
			else
			{
				const GLenum ifmt = gl::get_sized_internal_format(gcm_format);
				return create_temporary_subresource(src->id(), ifmt, x, y, w, h);
			}
		}

		cached_texture_section* create_new_texture(void*&, u32 rsx_address, u32 rsx_size, u16 width, u16 height, u16 depth, u16 mipmaps, const u32 gcm_format,
				const rsx::texture_dimension_extended type, const rsx::texture_create_flags flags, std::pair<std::array<u8, 4>, std::array<u8, 4>>& remap_vector) override
		{
			u32 vram_texture = gl::create_texture(gcm_format, width, height, depth, mipmaps, type);
			bool depth_flag = false;

			switch (gcm_format)
			{
			case CELL_GCM_TEXTURE_DEPTH24_D8:
			case CELL_GCM_TEXTURE_DEPTH16:
				depth_flag = true;
				break;
			}

			auto& cached = create_texture(vram_texture, rsx_address, rsx_size, width, height);
			cached.protect(utils::protection::ro);
			cached.set_dirty(false);
			cached.set_depth_flag(depth_flag);

			return &cached;
		}

		cached_texture_section* upload_image_from_cpu(void*&, u32 rsx_address, u16 width, u16 height, u16 depth, u16 mipmaps, u16 pitch, const u32 gcm_format,
			std::vector<rsx_subresource_layout>& subresource_layout, const rsx::texture_dimension_extended type, const bool swizzled,
			std::pair<std::array<u8, 4>, std::array<u8, 4>>& remap_vector) override
		{
			void* unused = nullptr;
			auto section = create_new_texture(unused, rsx_address, pitch * height, width, height, depth, mipmaps, gcm_format, type,
				rsx::texture_create_flags::default_component_order, remap_vector);

			gl::upload_texture(section->get_raw_texture(), rsx_address, gcm_format, width, height, depth, mipmaps, pitch, swizzled, type, subresource_layout, remap_vector, false);
			return section;
		}

		void enforce_surface_creation_type(cached_texture_section& section, const rsx::texture_create_flags flags) override
		{
		}

		void insert_texture_barrier() override
		{
			auto &caps = gl::get_driver_caps();

			if (caps.ARB_texture_barrier_supported)
				glTextureBarrier();
			else if (caps.NV_texture_barrier_supported)
				glTextureBarrierNV();
		}

	public:

		texture_cache() {}

		~texture_cache() {}

		void initialize()
		{
			m_hw_blitter.init();
		}

		void destroy() override
		{
			clear();
			m_hw_blitter.destroy();
		}
		
		bool is_depth_texture(const u32 rsx_address) override
		{
			auto section = find_texture_from_range(rsx_address, 64u);
			if (section != nullptr) return section->is_depth_texture();

			return false;
		}

		void on_frame_end() override
		{
			if (m_unreleased_texture_objects >= m_max_zombie_objects)
			{
				purge_dirty();
			}
			
			clear_temporary_subresources();
		}

		bool blit(rsx::blit_src_info& src, rsx::blit_dst_info& dst, bool linear_interpolate, gl_render_targets& m_rtts)
		{
			void* unused = nullptr;
			return upload_scaled_image(src, dst, linear_interpolate, unused, m_rtts, m_hw_blitter);
		}

		template<typename RsxTextureType>
		void upload_and_bind_texture(int index, GLenum target, RsxTextureType &tex, gl_render_targets &m_rtts)
		{
			glActiveTexture(GL_TEXTURE0 + index);
			void* unused = nullptr;

			auto id = upload_texture(unused, tex, m_rtts);
			glBindTexture(target, id);
		}
	};
}