// 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_egl_api_implementation.h"

#include "base/command_line.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"

namespace gl {

namespace {

void GL_BINDING_CALL MarshalClearDepthToClearDepthf(GLclampd depth) {
  glClearDepthf(static_cast<GLclampf>(depth));
}

void GL_BINDING_CALL MarshalDepthRangeToDepthRangef(GLclampd z_near,
                                                    GLclampd z_far) {
  glDepthRangef(static_cast<GLclampf>(z_near), static_cast<GLclampf>(z_far));
}

}  // namespace

RealEGLApi* g_real_egl;

void InitializeStaticGLBindingsEGL() {
  g_driver_egl.InitializeStaticBindings();
  if (!g_real_egl) {
    g_real_egl = new RealEGLApi();
  }
  g_real_egl->Initialize(&g_driver_egl);
  g_current_egl_context = g_real_egl;

  // These two functions take single precision float rather than double
  // precision float parameters in GLES.
  ::gl::g_driver_gl.fn.glClearDepthFn = MarshalClearDepthToClearDepthf;
  ::gl::g_driver_gl.fn.glDepthRangeFn = MarshalDepthRangeToDepthRangef;
}

void InitializeDebugGLBindingsEGL() {
  g_driver_egl.InitializeDebugBindings();
}

void ClearGLBindingsEGL() {
  if (g_real_egl) {
    delete g_real_egl;
    g_real_egl = NULL;
  }
  g_current_egl_context = NULL;
  g_driver_egl.ClearBindings();
}

EGLApi::EGLApi() {
}

EGLApi::~EGLApi() {
}

EGLApiBase::EGLApiBase()
    : driver_(NULL) {
}

EGLApiBase::~EGLApiBase() {
}

void EGLApiBase::InitializeBase(DriverEGL* driver) {
  driver_ = driver;
}

RealEGLApi::RealEGLApi() {
}

RealEGLApi::~RealEGLApi() {
}

void RealEGLApi::Initialize(DriverEGL* driver) {
  InitializeWithCommandLine(driver, base::CommandLine::ForCurrentProcess());
}

void RealEGLApi::InitializeWithCommandLine(DriverEGL* driver,
                                           base::CommandLine* command_line) {
  DCHECK(command_line);
  InitializeBase(driver);

  const std::string disabled_extensions = command_line->GetSwitchValueASCII(
      switches::kDisableGLExtensions);
  disabled_exts_.clear();
  filtered_exts_.clear();
  if (!disabled_extensions.empty()) {
    disabled_exts_ = base::SplitString(
        disabled_extensions, ", ;",
        base::KEEP_WHITESPACE, base::SPLIT_WANT_NONEMPTY);
  }
}

const char* RealEGLApi::eglQueryStringFn(EGLDisplay dpy, EGLint name) {
  if (name == EGL_EXTENSIONS) {
    auto it = filtered_exts_.find(dpy);
    if (it == filtered_exts_.end()) {
      it = filtered_exts_.insert(std::make_pair(
          dpy, FilterGLExtensionList(EGLApiBase::eglQueryStringFn(dpy, name),
                                     disabled_exts_))).first;
    }
    return (*it).second.c_str();
  }
  return EGLApiBase::eglQueryStringFn(dpy, name);
}

TraceEGLApi::~TraceEGLApi() {
}

bool GetGLWindowSystemBindingInfoEGL(GLWindowSystemBindingInfo* info) {
  EGLDisplay display = eglGetCurrentDisplay();
  const char* vendor = eglQueryString(display, EGL_VENDOR);
  const char* version = eglQueryString(display, EGL_VERSION);
  const char* extensions = eglQueryString(display, EGL_EXTENSIONS);
  *info = GLWindowSystemBindingInfo();
  if (vendor)
    info->vendor = vendor;
  if (version)
    info->version = version;
  if (extensions)
    info->extensions = extensions;
  return true;
}

}  // namespace gl