// Copyright 2008 Dolphin Emulator Project
// Licensed under GPLv2+
// Refer to the license.txt file included.

#include <algorithm>

#include "Common/CPUDetect.h"
#include "Common/CommonTypes.h"
#include "Common/StringUtil.h"
#include "Core/Config/GraphicsSettings.h"
#include "Core/ConfigManager.h"
#include "Core/Core.h"
#include "Core/Movie.h"
#include "VideoCommon/OnScreenDisplay.h"
#include "VideoCommon/VideoCommon.h"
#include "VideoCommon/VideoConfig.h"

VideoConfig g_Config;
VideoConfig g_ActiveConfig;
static bool s_has_registered_callback = false;

static bool IsVSyncActive(bool enabled)
{
  // Vsync is disabled when the throttler is disabled by the tab key.
  return enabled && !Core::GetIsThrottlerTempDisabled() &&
         SConfig::GetInstance().m_EmulationSpeed == 1.0;
}

void UpdateActiveConfig()
{
  if (Movie::IsPlayingInput() && Movie::IsConfigSaved())
    Movie::SetGraphicsConfig();
  g_ActiveConfig = g_Config;
  g_ActiveConfig.bVSyncActive = IsVSyncActive(g_ActiveConfig.bVSync);
}

VideoConfig::VideoConfig()
{
  // Needed for the first frame, I think
  fAspectRatioHackW = 1;
  fAspectRatioHackH = 1;

  // disable all features by default
  backend_info.api_type = APIType::Nothing;
  backend_info.MaxTextureSize = 16384;
  backend_info.bSupportsExclusiveFullscreen = false;
  backend_info.bSupportsMultithreading = false;
  backend_info.bSupportsST3CTextures = false;
  backend_info.bSupportsBPTCTextures = false;

  bEnableValidationLayer = false;

#if defined(ANDROID)
  bBackendMultithreading = false;
#else
  bBackendMultithreading = true;
#endif
}

void VideoConfig::Refresh()
{
  if (!s_has_registered_callback)
  {
    // There was a race condition between the video thread and the host thread here, if
    // corrections need to be made by VerifyValidity(). Briefly, the config will contain
    // invalid values. Instead, pause emulation first, which will flush the video thread,
    // update the config and correct it, then resume emulation, after which the video
    // thread will detect the config has changed and act accordingly.
    Config::AddConfigChangedCallback([]() { Core::RunAsCPUThread([]() { g_Config.Refresh(); }); });
    s_has_registered_callback = true;
  }

  bVSync = Config::Get(Config::GFX_VSYNC);
  iAdapter = Config::Get(Config::GFX_ADAPTER);

  bWidescreenHack = Config::Get(Config::GFX_WIDESCREEN_HACK);
  aspect_mode = Config::Get(Config::GFX_ASPECT_RATIO);
  suggested_aspect_mode = Config::Get(Config::GFX_SUGGESTED_ASPECT_RATIO);
  bCrop = Config::Get(Config::GFX_CROP);
  iSafeTextureCache_ColorSamples = Config::Get(Config::GFX_SAFE_TEXTURE_CACHE_COLOR_SAMPLES);
  bShowFPS = Config::Get(Config::GFX_SHOW_FPS);
  bShowNetPlayPing = Config::Get(Config::GFX_SHOW_NETPLAY_PING);
  bShowNetPlayMessages = Config::Get(Config::GFX_SHOW_NETPLAY_MESSAGES);
  bLogRenderTimeToFile = Config::Get(Config::GFX_LOG_RENDER_TIME_TO_FILE);
  bOverlayStats = Config::Get(Config::GFX_OVERLAY_STATS);
  bOverlayProjStats = Config::Get(Config::GFX_OVERLAY_PROJ_STATS);
  bDumpTextures = Config::Get(Config::GFX_DUMP_TEXTURES);
  bHiresTextures = Config::Get(Config::GFX_HIRES_TEXTURES);
  bCacheHiresTextures = Config::Get(Config::GFX_CACHE_HIRES_TEXTURES);
  bDumpEFBTarget = Config::Get(Config::GFX_DUMP_EFB_TARGET);
  bDumpXFBTarget = Config::Get(Config::GFX_DUMP_XFB_TARGET);
  bDumpFramesAsImages = Config::Get(Config::GFX_DUMP_FRAMES_AS_IMAGES);
  bFreeLook = Config::Get(Config::GFX_FREE_LOOK);
  bUseFFV1 = Config::Get(Config::GFX_USE_FFV1);
  sDumpFormat = Config::Get(Config::GFX_DUMP_FORMAT);
  sDumpCodec = Config::Get(Config::GFX_DUMP_CODEC);
  sDumpEncoder = Config::Get(Config::GFX_DUMP_ENCODER);
  sDumpPath = Config::Get(Config::GFX_DUMP_PATH);
  iBitrateKbps = Config::Get(Config::GFX_BITRATE_KBPS);
  bInternalResolutionFrameDumps = Config::Get(Config::GFX_INTERNAL_RESOLUTION_FRAME_DUMPS);
  bEnableGPUTextureDecoding = Config::Get(Config::GFX_ENABLE_GPU_TEXTURE_DECODING);
  bEnablePixelLighting = Config::Get(Config::GFX_ENABLE_PIXEL_LIGHTING);
  bFastDepthCalc = Config::Get(Config::GFX_FAST_DEPTH_CALC);
  iMultisamples = Config::Get(Config::GFX_MSAA);
  bSSAA = Config::Get(Config::GFX_SSAA);
  iEFBScale = Config::Get(Config::GFX_EFB_SCALE);
  bTexFmtOverlayEnable = Config::Get(Config::GFX_TEXFMT_OVERLAY_ENABLE);
  bTexFmtOverlayCenter = Config::Get(Config::GFX_TEXFMT_OVERLAY_CENTER);
  bWireFrame = Config::Get(Config::GFX_ENABLE_WIREFRAME);
  bDisableFog = Config::Get(Config::GFX_DISABLE_FOG);
  bBorderlessFullscreen = Config::Get(Config::GFX_BORDERLESS_FULLSCREEN);
  bEnableValidationLayer = Config::Get(Config::GFX_ENABLE_VALIDATION_LAYER);
  bBackendMultithreading = Config::Get(Config::GFX_BACKEND_MULTITHREADING);
  iCommandBufferExecuteInterval = Config::Get(Config::GFX_COMMAND_BUFFER_EXECUTE_INTERVAL);
  bShaderCache = Config::Get(Config::GFX_SHADER_CACHE);
  bWaitForShadersBeforeStarting = Config::Get(Config::GFX_WAIT_FOR_SHADERS_BEFORE_STARTING);
  iShaderCompilationMode = Config::Get(Config::GFX_SHADER_COMPILATION_MODE);
  iShaderCompilerThreads = Config::Get(Config::GFX_SHADER_COMPILER_THREADS);
  iShaderPrecompilerThreads = Config::Get(Config::GFX_SHADER_PRECOMPILER_THREADS);

  bZComploc = Config::Get(Config::GFX_SW_ZCOMPLOC);
  bZFreeze = Config::Get(Config::GFX_SW_ZFREEZE);
  bDumpObjects = Config::Get(Config::GFX_SW_DUMP_OBJECTS);
  bDumpTevStages = Config::Get(Config::GFX_SW_DUMP_TEV_STAGES);
  bDumpTevTextureFetches = Config::Get(Config::GFX_SW_DUMP_TEV_TEX_FETCHES);
  drawStart = Config::Get(Config::GFX_SW_DRAW_START);
  drawEnd = Config::Get(Config::GFX_SW_DRAW_END);

  bForceFiltering = Config::Get(Config::GFX_ENHANCE_FORCE_FILTERING);
  iMaxAnisotropy = Config::Get(Config::GFX_ENHANCE_MAX_ANISOTROPY);
  sPostProcessingShader = Config::Get(Config::GFX_ENHANCE_POST_SHADER);
  bForceTrueColor = Config::Get(Config::GFX_ENHANCE_FORCE_TRUE_COLOR);
  bDisableCopyFilter = Config::Get(Config::GFX_ENHANCE_DISABLE_COPY_FILTER);
  bArbitraryMipmapDetection = Config::Get(Config::GFX_ENHANCE_ARBITRARY_MIPMAP_DETECTION);
  fArbitraryMipmapDetectionThreshold =
      Config::Get(Config::GFX_ENHANCE_ARBITRARY_MIPMAP_DETECTION_THRESHOLD);

  stereo_mode = Config::Get(Config::GFX_STEREO_MODE);
  iStereoDepth = Config::Get(Config::GFX_STEREO_DEPTH);
  iStereoConvergencePercentage = Config::Get(Config::GFX_STEREO_CONVERGENCE_PERCENTAGE);
  bStereoSwapEyes = Config::Get(Config::GFX_STEREO_SWAP_EYES);
  iStereoConvergence = Config::Get(Config::GFX_STEREO_CONVERGENCE);
  bStereoEFBMonoDepth = Config::Get(Config::GFX_STEREO_EFB_MONO_DEPTH);
  iStereoDepthPercentage = Config::Get(Config::GFX_STEREO_DEPTH_PERCENTAGE);

  bEFBAccessEnable = Config::Get(Config::GFX_HACK_EFB_ACCESS_ENABLE);
  bEFBAccessDeferInvalidation = Config::Get(Config::GFX_HACK_EFB_DEFER_INVALIDATION);
  bBBoxEnable = Config::Get(Config::GFX_HACK_BBOX_ENABLE);
  bForceProgressive = Config::Get(Config::GFX_HACK_FORCE_PROGRESSIVE);
  bSkipEFBCopyToRam = Config::Get(Config::GFX_HACK_SKIP_EFB_COPY_TO_RAM);
  bSkipXFBCopyToRam = Config::Get(Config::GFX_HACK_SKIP_XFB_COPY_TO_RAM);
  bDisableCopyToVRAM = Config::Get(Config::GFX_HACK_DISABLE_COPY_TO_VRAM);
  bDeferEFBCopies = Config::Get(Config::GFX_HACK_DEFER_EFB_COPIES);
  bImmediateXFB = Config::Get(Config::GFX_HACK_IMMEDIATE_XFB);
  bSkipPresentingDuplicateXFBs = Config::Get(Config::GFX_HACK_SKIP_DUPLICATE_XFBS);
  bCopyEFBScaled = Config::Get(Config::GFX_HACK_COPY_EFB_SCALED);
  bEFBEmulateFormatChanges = Config::Get(Config::GFX_HACK_EFB_EMULATE_FORMAT_CHANGES);
  bVertexRounding = Config::Get(Config::GFX_HACK_VERTEX_ROUDING);
  iEFBAccessTileSize = Config::Get(Config::GFX_HACK_EFB_ACCESS_TILE_SIZE);

  bPerfQueriesEnable = Config::Get(Config::GFX_PERF_QUERIES_ENABLE);

  VerifyValidity();
}

void VideoConfig::VerifyValidity()
{
  // TODO: Check iMaxAnisotropy value
  if (iAdapter < 0 || iAdapter > ((int)backend_info.Adapters.size() - 1))
    iAdapter = 0;

  if (std::find(backend_info.AAModes.begin(), backend_info.AAModes.end(), iMultisamples) ==
      backend_info.AAModes.end())
    iMultisamples = 1;

  if (stereo_mode != StereoMode::Off)
  {
    if (!backend_info.bSupportsGeometryShaders)
    {
      OSD::AddMessage(
          "Stereoscopic 3D isn't supported by your GPU, support for OpenGL 3.2 is required.",
          10000);
      stereo_mode = StereoMode::Off;
    }
  }
}

bool VideoConfig::UsingUberShaders() const
{
  return iShaderCompilationMode == ShaderCompilationMode::SynchronousUberShaders ||
         iShaderCompilationMode == ShaderCompilationMode::AsynchronousUberShaders;
}

static u32 GetNumAutoShaderCompilerThreads()
{
  // Automatic number. We use clamp(cpus - 3, 1, 4).
  return static_cast<u32>(std::min(std::max(cpu_info.num_cores - 3, 1), 4));
}

u32 VideoConfig::GetShaderCompilerThreads() const
{
  if (!backend_info.bSupportsBackgroundCompiling)
    return 0;

  if (iShaderCompilerThreads >= 0)
    return static_cast<u32>(iShaderCompilerThreads);
  else
    return GetNumAutoShaderCompilerThreads();
}

u32 VideoConfig::GetShaderPrecompilerThreads() const
{
  // When using background compilation, always keep the same thread count.
  if (!bWaitForShadersBeforeStarting)
    return GetShaderCompilerThreads();

  if (!backend_info.bSupportsBackgroundCompiling)
    return 0;

  if (iShaderPrecompilerThreads >= 0)
    return static_cast<u32>(iShaderPrecompilerThreads);
  else
    return GetNumAutoShaderCompilerThreads();
}