// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "ui/gl/gl_glx_api_implementation.h"

#include "base/command_line.h"
#include "base/strings/string_number_conversions.h"
#include "base/strings/string_split.h"
#include "base/strings/string_util.h"
#include "ui/gl/gl_context.h"
#include "ui/gl/gl_implementation.h"
#include "ui/gl/gl_surface_glx.h"
#include "ui/gl/gl_version_info.h"

namespace gl {

RealGLXApi* g_real_glx;
DebugGLXApi* g_debug_glx;

void InitializeStaticGLBindingsGLX() {
  g_driver_glx.InitializeStaticBindings();
  if (!g_real_glx) {
    g_real_glx = new RealGLXApi();
  }
  g_real_glx->Initialize(&g_driver_glx);
  g_current_glx_context = g_real_glx;
}

void InitializeDebugGLBindingsGLX() {
  if (!g_debug_glx) {
    g_debug_glx = new DebugGLXApi(g_real_glx);
  }
  g_current_glx_context = g_debug_glx;
}

void ClearBindingsGLX() {
  if (g_debug_glx) {
    delete g_debug_glx;
    g_debug_glx = NULL;
  }
  if (g_real_glx) {
    delete g_real_glx;
    g_real_glx = NULL;
  }
  g_current_glx_context = NULL;
  g_driver_glx.ClearBindings();
}

GLXApi::GLXApi() {
}

GLXApi::~GLXApi() {
}

GLXApiBase::GLXApiBase()
    : driver_(NULL) {
}

GLXApiBase::~GLXApiBase() {
}

void GLXApiBase::InitializeBase(DriverGLX* driver) {
  driver_ = driver;
}

RealGLXApi::RealGLXApi() {
}

RealGLXApi::~RealGLXApi() {
}

void RealGLXApi::Initialize(DriverGLX* driver) {
  InitializeBase(driver);
}

void RealGLXApi::SetDisabledExtensions(const std::string& disabled_extensions) {
  disabled_exts_.clear();
  filtered_exts_ = "";
  if (!disabled_extensions.empty()) {
    disabled_exts_ =
        base::SplitString(disabled_extensions, ", ;",
                          base::KEEP_WHITESPACE,
                          base::SPLIT_WANT_NONEMPTY);
  }
}

const char* RealGLXApi::glXQueryExtensionsStringFn(Display* dpy,
                                                   int screen) {
  if (filtered_exts_.size())
    return filtered_exts_.c_str();

  if (!driver_->fn.glXQueryExtensionsStringFn)
    return NULL;

  const char* str = GLXApiBase::glXQueryExtensionsStringFn(dpy, screen);
  if (!str)
    return NULL;

  filtered_exts_ = FilterGLExtensionList(str, disabled_exts_);
  return filtered_exts_.c_str();
}

DebugGLXApi::DebugGLXApi(GLXApi* glx_api) : glx_api_(glx_api) {}

DebugGLXApi::~DebugGLXApi() {}

void DebugGLXApi::SetDisabledExtensions(
    const std::string& disabled_extensions) {
  if (glx_api_) {
    glx_api_->SetDisabledExtensions(disabled_extensions);
  }
}

TraceGLXApi::~TraceGLXApi() {
}

void TraceGLXApi::SetDisabledExtensions(
    const std::string& disabled_extensions) {
  if (glx_api_) {
    glx_api_->SetDisabledExtensions(disabled_extensions);
  }
}

bool GetGLWindowSystemBindingInfoGLX(const GLVersionInfo& gl_info,
                                     GLWindowSystemBindingInfo* info) {
  Display* display = glXGetCurrentDisplay();
  const int kDefaultScreen = 0;
  const char* vendor =
      glXQueryServerString(display, kDefaultScreen, GLX_VENDOR);
  const char* version =
      glXQueryServerString(display, kDefaultScreen, GLX_VERSION);
  const char* extensions =
      glXQueryServerString(display, kDefaultScreen, GLX_EXTENSIONS);
  *info = GLWindowSystemBindingInfo();
  if (vendor)
    info->vendor = vendor;
  if (version)
    info->version = version;
  if (extensions)
    info->extensions = extensions;
  if (glXIsDirect(display, glXGetCurrentContext())) {
    info->direct_rendering_version = "2";
    bool using_mesa = gl_info.driver_vendor.find("Mesa") != std::string::npos ||
                      gl_info.driver_version.find("Mesa") != std::string::npos;
    if (using_mesa) {
      std::vector<std::string> split_version =
          base::SplitString(gl_info.driver_version, ".", base::TRIM_WHITESPACE,
                            base::SPLIT_WANT_ALL);
      int ext_code, first_event, first_error;
      unsigned major_num = 0;
      base::StringToUint(split_version[0], &major_num);
      // Mesa after version 17 will reliably use DRI3 when available.
      if (major_num >= 17 && XQueryExtension(display, "DRI3", &ext_code,
                                             &first_event, &first_error)) {
        info->direct_rendering_version = "2.3";
      } else if (XQueryExtension(display, "DRI2", &ext_code, &first_event,
                                 &first_error)) {
        info->direct_rendering_version = "2.2";
      } else if (XQueryExtension(display, "DRI", &ext_code, &first_event,
                                 &first_error)) {
        info->direct_rendering_version = "2.1";
      }
    }
  } else {
    info->direct_rendering_version = "1";
  }
  return true;
}

void SetDisabledExtensionsGLX(const std::string& disabled_extensions) {
  DCHECK(g_current_glx_context);
  DCHECK(GLContext::TotalGLContexts() == 0);
  g_current_glx_context->SetDisabledExtensions(disabled_extensions);
}

bool InitializeExtensionSettingsOneOffGLX() {
  return GLSurfaceGLX::InitializeExtensionSettingsOneOff();
}

}  // namespace gl