// Copyright 2014 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_surface.h"

#include "base/logging.h"
#include "base/memory/ref_counted.h"
#include "third_party/khronos/EGL/egl.h"
#include "ui/gfx/native_widget_types.h"
#include "ui/gl/gl_implementation.h"
#include "ui/gl/gl_surface_egl.h"
#include "ui/gl/gl_surface_osmesa.h"
#include "ui/gl/gl_surface_stub.h"

namespace gfx {

// static
bool GLSurface::InitializeOneOffInternal() {
  auto implementation = GetGLImplementation();
  switch (implementation) {
    case kGLImplementationEGLGLES2:
      if (!GLSurfaceEGL::InitializeOneOff()) {
        LOG(ERROR) << "GLSurfaceEGL::InitializeOneOff failed.";
        return false;
      }
      break;
    default:
      LOG(ERROR)
          << "Unknown GL implementation returned from GetGLImplementation: "
          << implementation;
      return false;
  }
  return true;
}

// static
scoped_refptr<GLSurface> GLSurface::CreateViewGLSurface(
    gfx::AcceleratedWidget window,
    const gfx::SurfaceConfiguration& requested_configuration) {
  CHECK_NE(kGLImplementationNone, GetGLImplementation());
  if (GetGLImplementation() == kGLImplementationOSMesaGL) {
    scoped_refptr<GLSurface> surface(
        new GLSurfaceOSMesaHeadless(requested_configuration));
    if (!surface->Initialize())
      return NULL;
    return surface;
  }
  DCHECK(GetGLImplementation() == kGLImplementationEGLGLES2);
  if (window != kNullAcceleratedWidget) {
    scoped_refptr<GLSurface> surface =
        new NativeViewGLSurfaceEGL(window, requested_configuration);
    if (surface->Initialize())
      return surface;
  } else {
    scoped_refptr<GLSurface> surface =
        new GLSurfaceStub(requested_configuration);
    if (surface->Initialize())
      return surface;
  }
  return NULL;
}

// static
scoped_refptr<GLSurface> GLSurface::CreateOffscreenGLSurface(
    const gfx::Size& size,
    const gfx::SurfaceConfiguration& requested_configuration) {
  CHECK_NE(kGLImplementationNone, GetGLImplementation());
  switch (GetGLImplementation()) {
    case kGLImplementationOSMesaGL: {
      scoped_refptr<GLSurface> surface(new GLSurfaceOSMesa(
          OSMesaSurfaceFormatBGRA, size, requested_configuration));
      if (!surface->Initialize())
        return NULL;

      return surface;
    }
    case kGLImplementationEGLGLES2: {
      scoped_refptr<GLSurface> surface;
      if (GLSurfaceEGL::IsEGLSurfacelessContextSupported() &&
          (size.width() == 0 && size.height() == 0)) {
        surface = new SurfacelessEGL(size, requested_configuration);
      } else {
        surface = new PbufferGLSurfaceEGL(size, requested_configuration);
      }

      if (!surface->Initialize())
        return NULL;
      return surface;
    }
    default:
      NOTREACHED();
      return NULL;
  }
}

EGLNativeDisplayType GetPlatformDefaultEGLNativeDisplay() {
  return EGL_DEFAULT_DISPLAY;
}

}  // namespace gfx