// Copyright 2010 Dolphin Emulator Project
// Licensed under GPLv2+
// Refer to the license.txt file included.

// ---------------------------------------------------------------------------------------------
// GC graphics pipeline
// ---------------------------------------------------------------------------------------------
// 3d commands are issued through the fifo. The GPU draws to the 2MB EFB.
// The efb can be copied back into ram in two forms: as textures or as XFB.
// The XFB is the region in RAM that the VI chip scans out to the television.
// So, after all rendering to EFB is done, the image is copied into one of two XFBs in RAM.
// Next frame, that one is scanned out and the other one gets the copy. = double buffering.
// ---------------------------------------------------------------------------------------------

#pragma once

#include <array>
#include <condition_variable>
#include <memory>
#include <mutex>
#include <string>
#include <thread>
#include <tuple>
#include <vector>

#include "Common/CommonTypes.h"
#include "Common/Event.h"
#include "Common/Flag.h"
#include "Common/MathUtil.h"
#include "VideoCommon/AVIDump.h"
#include "VideoCommon/AsyncShaderCompiler.h"
#include "VideoCommon/BPMemory.h"
#include "VideoCommon/FPSCounter.h"
#include "VideoCommon/RenderState.h"
#include "VideoCommon/TextureConfig.h"
#include "VideoCommon/VideoCommon.h"

class AbstractFramebuffer;
class AbstractPipeline;
class AbstractShader;
class AbstractTexture;
class AbstractStagingTexture;
class PostProcessingShaderImplementation;
struct TextureConfig;
struct ComputePipelineConfig;
struct AbstractPipelineConfig;
enum class ShaderStage;
enum class EFBAccessType;
enum class StagingTextureType;

struct EfbPokeData
{
  u16 x, y;
  u32 data;
};

extern int frameCount;

enum class OSDMessage : s32
{
  IRChanged = 1,
  ARToggled = 2,
  EFBCopyToggled = 3,
  FogToggled = 4,
  SpeedChanged = 5,
  XFBChanged = 6,
  VolumeChanged = 7,
};

// Renderer really isn't a very good name for this class - it's more like "Misc".
// The long term goal is to get rid of this class and replace it with others that make
// more sense.
class Renderer
{
public:
  Renderer(int backbuffer_width, int backbuffer_height, AbstractTextureFormat backbuffer_format);
  virtual ~Renderer();

  using ClearColor = std::array<float, 4>;

  virtual bool IsHeadless() const = 0;

  virtual bool Initialize();
  virtual void Shutdown();

  virtual void SetPipeline(const AbstractPipeline* pipeline) {}
  virtual void SetScissorRect(const MathUtil::Rectangle<int>& rc) {}
  virtual void SetTexture(u32 index, const AbstractTexture* texture) {}
  virtual void SetSamplerState(u32 index, const SamplerState& state) {}
  virtual void UnbindTexture(const AbstractTexture* texture) {}
  virtual void SetInterlacingMode() {}
  virtual void SetViewport(float x, float y, float width, float height, float near_depth,
                           float far_depth)
  {
  }
  virtual void SetFullscreen(bool enable_fullscreen) {}
  virtual bool IsFullscreen() const { return false; }
  virtual void ApplyState() {}
  virtual void RestoreState() {}
  virtual void ResetAPIState() {}
  virtual void RestoreAPIState() {}
  virtual std::unique_ptr<AbstractTexture> CreateTexture(const TextureConfig& config) = 0;
  virtual std::unique_ptr<AbstractStagingTexture>
  CreateStagingTexture(StagingTextureType type, const TextureConfig& config) = 0;
  virtual std::unique_ptr<AbstractFramebuffer>
  CreateFramebuffer(const AbstractTexture* color_attachment,
                    const AbstractTexture* depth_attachment) = 0;

  // Framebuffer operations.
  virtual void SetFramebuffer(const AbstractFramebuffer* framebuffer) {}
  virtual void SetAndDiscardFramebuffer(const AbstractFramebuffer* framebuffer) {}
  virtual void SetAndClearFramebuffer(const AbstractFramebuffer* framebuffer,
                                      const ClearColor& color_value = {}, float depth_value = 0.0f)
  {
  }

  // Drawing with currently-bound pipeline state.
  virtual void Draw(u32 base_vertex, u32 num_vertices) {}
  virtual void DrawIndexed(u32 base_index, u32 num_indices, u32 base_vertex) {}

  // Shader modules/objects.
  virtual std::unique_ptr<AbstractShader>
  CreateShaderFromSource(ShaderStage stage, const char* source, size_t length) = 0;
  virtual std::unique_ptr<AbstractShader>
  CreateShaderFromBinary(ShaderStage stage, const void* data, size_t length) = 0;
  virtual std::unique_ptr<AbstractPipeline>
  CreatePipeline(const AbstractPipelineConfig& config) = 0;

  const AbstractFramebuffer* GetCurrentFramebuffer() const { return m_current_framebuffer; }
  u32 GetCurrentFramebufferWidth() const { return m_current_framebuffer_width; }
  u32 GetCurrentFramebufferHeight() const { return m_current_framebuffer_height; }
  // Ideal internal resolution - multiple of the native EFB resolution
  int GetTargetWidth() const { return m_target_width; }
  int GetTargetHeight() const { return m_target_height; }
  // Display resolution
  int GetBackbufferWidth() const { return m_backbuffer_width; }
  int GetBackbufferHeight() const { return m_backbuffer_height; }
  void SetWindowSize(int width, int height);

  // EFB coordinate conversion functions

  // Use this to convert a whole native EFB rect to backbuffer coordinates
  virtual TargetRectangle ConvertEFBRectangle(const EFBRectangle& rc) = 0;

  const TargetRectangle& GetTargetRectangle() const { return m_target_rectangle; }
  float CalculateDrawAspectRatio() const;

  std::tuple<float, float> ScaleToDisplayAspectRatio(int width, int height) const;
  void UpdateDrawRectangle();

  // Use this to convert a single target rectangle to two stereo rectangles
  std::tuple<TargetRectangle, TargetRectangle>
  ConvertStereoRectangle(const TargetRectangle& rc) const;

  unsigned int GetEFBScale() const;

  // Use this to upscale native EFB coordinates to IDEAL internal resolution
  int EFBToScaledX(int x) const;
  int EFBToScaledY(int y) const;

  // Floating point versions of the above - only use them if really necessary
  float EFBToScaledXf(float x) const;
  float EFBToScaledYf(float y) const;

  // Random utilities
  void SaveScreenshot(const std::string& filename, bool wait_for_completion);
  void DrawDebugText();

  virtual void RenderText(const std::string& text, int left, int top, u32 color) = 0;

  virtual void ClearScreen(const EFBRectangle& rc, bool colorEnable, bool alphaEnable, bool zEnable,
                           u32 color, u32 z) = 0;
  virtual void ReinterpretPixelData(unsigned int convtype) = 0;
  void RenderToXFB(u32 xfbAddr, const EFBRectangle& sourceRc, u32 fbStride, u32 fbHeight,
                   float Gamma = 1.0f);

  virtual u32 AccessEFB(EFBAccessType type, u32 x, u32 y, u32 poke_data) = 0;
  virtual void PokeEFB(EFBAccessType type, const EfbPokeData* points, size_t num_points) = 0;

  virtual u16 BBoxRead(int index) = 0;
  virtual void BBoxWrite(int index, u16 value) = 0;

  // Finish up the current frame, print some stats
  void Swap(u32 xfbAddr, u32 fbWidth, u32 fbStride, u32 fbHeight, const EFBRectangle& rc,
            u64 ticks);
  virtual void SwapImpl(AbstractTexture* texture, const EFBRectangle& rc, u64 ticks) = 0;
  virtual void Flush() {}

  PEControl::PixelFormat GetPrevPixelFormat() const { return m_prev_efb_format; }
  void StorePixelFormat(PEControl::PixelFormat new_format) { m_prev_efb_format = new_format; }
  PostProcessingShaderImplementation* GetPostProcessor() const { return m_post_processor.get(); }
  // Final surface changing
  // This is called when the surface is resized (WX) or the window changes (Android).
  void ChangeSurface(void* new_surface_handle);
  void ResizeSurface();
  bool UseVertexDepthRange() const;

  virtual std::unique_ptr<VideoCommon::AsyncShaderCompiler> CreateAsyncShaderCompiler();

  void ShowOSDMessage(OSDMessage message);

protected:
  std::tuple<int, int> CalculateTargetScale(int x, int y) const;
  bool CalculateTargetSize();

  bool CheckForHostConfigChanges();

  void CheckFifoRecording();
  void RecordVideoMemory();

  // TODO: Remove the width/height parameters once we make the EFB an abstract framebuffer.
  const AbstractFramebuffer* m_current_framebuffer = nullptr;
  u32 m_current_framebuffer_width = 1;
  u32 m_current_framebuffer_height = 1;

  Common::Flag m_screenshot_request;
  Common::Event m_screenshot_completed;
  std::mutex m_screenshot_lock;
  std::string m_screenshot_name;
  bool m_aspect_wide = false;

  // The framebuffer size
  int m_target_width = 0;
  int m_target_height = 0;

  // Backbuffer (window) size and render area
  int m_backbuffer_width = 0;
  int m_backbuffer_height = 0;
  AbstractTextureFormat m_backbuffer_format = AbstractTextureFormat::Undefined;
  TargetRectangle m_target_rectangle = {};

  FPSCounter m_fps_counter;

  std::unique_ptr<PostProcessingShaderImplementation> m_post_processor;

  void* m_new_surface_handle = nullptr;
  Common::Flag m_surface_changed;
  Common::Flag m_surface_resized;
  std::mutex m_swap_mutex;

  u32 m_last_host_config_bits = 0;
  u32 m_last_efb_multisamples = 1;

private:
  void RunFrameDumps();
  std::tuple<int, int> CalculateOutputDimensions(int width, int height);

  PEControl::PixelFormat m_prev_efb_format = PEControl::INVALID_FMT;
  unsigned int m_efb_scale = 1;

  // These will be set on the first call to SetWindowSize.
  int m_last_window_request_width = 0;
  int m_last_window_request_height = 0;

  // frame dumping
  std::thread m_frame_dump_thread;
  Common::Event m_frame_dump_start;
  Common::Event m_frame_dump_done;
  Common::Flag m_frame_dump_thread_running;
  u32 m_frame_dump_image_counter = 0;
  bool m_frame_dump_frame_running = false;
  struct FrameDumpConfig
  {
    const u8* data;
    int width;
    int height;
    int stride;
    AVIDump::Frame state;
  } m_frame_dump_config;

  // Texture used for screenshot/frame dumping
  std::unique_ptr<AbstractTexture> m_frame_dump_render_texture;
  std::array<std::unique_ptr<AbstractStagingTexture>, 2> m_frame_dump_readback_textures;
  AVIDump::Frame m_last_frame_state;
  bool m_last_frame_exported = false;

  // Tracking of XFB textures so we don't render duplicate frames.
  AbstractTexture* m_last_xfb_texture = nullptr;
  u64 m_last_xfb_id = std::numeric_limits<u64>::max();
  u64 m_last_xfb_ticks = 0;
  EFBRectangle m_last_xfb_region;

  // Note: Only used for auto-ir
  u32 m_last_xfb_width = MAX_XFB_WIDTH;
  u32 m_last_xfb_height = MAX_XFB_HEIGHT;

  s32 m_osd_message = 0;
  s32 m_osd_time = 0;

  // NOTE: The methods below are called on the framedumping thread.
  bool StartFrameDumpToAVI(const FrameDumpConfig& config);
  void DumpFrameToAVI(const FrameDumpConfig& config);
  void StopFrameDumpToAVI();
  std::string GetFrameDumpNextImageFileName() const;
  bool StartFrameDumpToImage(const FrameDumpConfig& config);
  void DumpFrameToImage(const FrameDumpConfig& config);
  void ShutdownFrameDumping();

  bool IsFrameDumping();

  // Asynchronously encodes the current staging texture to the frame dump.
  void DumpCurrentFrame();

  // Fills the frame dump render texture with the current XFB texture.
  void RenderFrameDump();

  // Queues the current frame for readback, which will be written to AVI next frame.
  void QueueFrameDumpReadback();

  // Asynchronously encodes the specified pointer of frame data to the frame dump.
  void DumpFrameData(const u8* data, int w, int h, int stride, const AVIDump::Frame& state);

  // Ensures all rendered frames are queued for encoding.
  void FlushFrameDump();

  // Ensures all encoded frames have been written to the output file.
  void FinishFrameData();
};

extern std::unique_ptr<Renderer> g_renderer;