/*

 * GStreamer

 * Copyright (C) 2012 Matthew Waters <ystreet00@gmail.com>

 *

 * This library is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Library General Public

 * License as published by the Free Software Foundation; either

 * version 2 of the License, or (at your option) any later version.

 *

 * This library is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

 * Library General Public License for more details.

 *

 * You should have received a copy of the GNU Library General Public

 * License along with this library; if not, write to the

 * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,

 * Boston, MA 02110-1301, USA.

 */

#ifdef HAVE_CONFIG_H

#include "config.h"

#endif

#include <Cocoa/Cocoa.h>

#include "gstglcontext_cocoa.h"

#include "gstgl_cocoa_private.h"

static gboolean gst_gl_context_cocoa_create_context (GstGLContext *context, GstGLAPI gl_api,

    GstGLContext * other_context, GError **error);

static void gst_gl_context_cocoa_destroy_context (GstGLContext *context);

static guintptr gst_gl_context_cocoa_get_gl_context (GstGLContext * window);

static gboolean gst_gl_context_cocoa_activate (GstGLContext * context, gboolean activate);

static GstGLAPI gst_gl_context_cocoa_get_gl_api (GstGLContext * context);

static GstGLPlatform gst_gl_context_cocoa_get_gl_platform (GstGLContext * context);

static void gst_gl_context_cocoa_swap_buffers (GstGLContext * context);

#define GST_GL_CONTEXT_COCOA_GET_PRIVATE(o)  \

  (G_TYPE_INSTANCE_GET_PRIVATE((o), GST_TYPE_GL_CONTEXT_COCOA, GstGLContextCocoaPrivate))

GST_DEBUG_CATEGORY_STATIC (gst_gl_context_cocoa_debug);

#define GST_CAT_DEFAULT gst_gl_context_cocoa_debug

G_DEFINE_TYPE_WITH_CODE (GstGLContextCocoa, gst_gl_context_cocoa,

    GST_TYPE_GL_CONTEXT, GST_DEBUG_CATEGORY_INIT (gst_gl_context_cocoa_debug, "glcontext_cocoa", 0, "Cocoa GL Context"); );

static void

gst_gl_context_cocoa_class_init (GstGLContextCocoaClass * klass)

{

  GstGLContextClass *context_class = (GstGLContextClass *) klass;

  g_type_class_add_private (klass, sizeof (GstGLContextCocoaPrivate));

  context_class->swap_buffers =

    GST_DEBUG_FUNCPTR (gst_gl_context_cocoa_swap_buffers);

  context_class->destroy_context =

      GST_DEBUG_FUNCPTR (gst_gl_context_cocoa_destroy_context);

  context_class->create_context =

      GST_DEBUG_FUNCPTR (gst_gl_context_cocoa_create_context);

  context_class->get_gl_context =

      GST_DEBUG_FUNCPTR (gst_gl_context_cocoa_get_gl_context);

  context_class->activate = GST_DEBUG_FUNCPTR (gst_gl_context_cocoa_activate);

  context_class->get_gl_api =

      GST_DEBUG_FUNCPTR (gst_gl_context_cocoa_get_gl_api);

  context_class->get_gl_platform =

      GST_DEBUG_FUNCPTR (gst_gl_context_cocoa_get_gl_platform);

}

static void

gst_gl_context_cocoa_init (GstGLContextCocoa * context)

{

  context->priv = GST_GL_CONTEXT_COCOA_GET_PRIVATE (context);

}

/* Must be called in the gl thread */

GstGLContextCocoa *

gst_gl_context_cocoa_new (GstGLDisplay * display)

{

  GstGLContextCocoa *context;

  if ((gst_gl_display_get_handle_type (display) & GST_GL_DISPLAY_TYPE_COCOA) == 0)

    /* we require an cocoa display to create CGL contexts */

    return NULL;

  context = g_object_new (GST_TYPE_GL_CONTEXT_COCOA, NULL);

  gst_object_ref_sink (context);

  return context;

}

struct pixel_attr

{

  CGLPixelFormatAttribute attr;

  const gchar *attr_name;

};

static struct pixel_attr pixel_attrs[] = {

  {kCGLPFAAllRenderers, "All Renderers"},

  {kCGLPFADoubleBuffer, "Double Buffered"},

  {kCGLPFAAuxBuffers, "Aux Buffers"},

  {kCGLPFAColorSize, "Color Size"},

  {kCGLPFAAlphaSize, "Alpha Size"},

  {kCGLPFADepthSize, "Depth Size"},

  {kCGLPFAStencilSize, "Stencil Size"},

  {kCGLPFAAccumSize, "Accum Size"},

  {kCGLPFAMinimumPolicy, "Minimum Policy"},

  {kCGLPFAMaximumPolicy, "Maximum Policy"},

  {kCGLPFASampleBuffers, "Sample Buffers"},

  {kCGLPFASamples, "Samples"},

  {kCGLPFAAuxDepthStencil, "Aux Depth Stencil"},

  {kCGLPFAColorFloat, "Color Float"},

  {kCGLPFAMultisample, "Multisample"},

  {kCGLPFASupersample, "Supersample"},

  {kCGLPFARendererID, "Renderer ID"},

  {kCGLPFANoRecovery, "No Recovery"},

  {kCGLPFAAccelerated, "Accelerated"},

  {kCGLPFAClosestPolicy, "Closest Policy"},

  {kCGLPFABackingStore, "Backing Store"},

  {kCGLPFADisplayMask, "Display Mask"},

  {kCGLPFAAllowOfflineRenderers, "Allow Offline Renderers"},

  {kCGLPFAAcceleratedCompute, "Accelerated Compute"},

  {kCGLPFAOpenGLProfile, "OpenGL Profile"},

  {kCGLPFAVirtualScreenCount, "Virtual Screen Count"},

#if MAC_OS_X_VERSION_MAX_ALLOWED < MAC_OS_X_VERSION_10_11

  {kCGLPFAStereo, "Stereo"},

#endif

#if MAC_OS_X_VERSION_MAX_ALLOWED < MAC_OS_X_VERSION_10_9

  {kCGLPFACompliant, "Compliant"},

  {kCGLPFARemotePBuffer, "Remote PBuffer"},

  {kCGLPFASingleRenderer, "Single Renderer"},

  {kCGLPFAWindow, "Window"},

#endif

#if MAC_OS_X_VERSION_MAX_ALLOWED < MAC_OS_X_VERSION_10_7

//  {kCGLPFAOffScreen, "Off Screen"},

//  {kCGLPFAPBuffer, "PBuffer"},

#endif

#if MAC_OS_X_VERSION_MAX_ALLOWED < MAC_OS_X_VERSION_10_6

//  {kCGLPFAFullScreen, "Full Screen"},

#endif

#if MAC_OS_X_VERSION_MAX_ALLOWED < MAC_OS_X_VERSION_10_5

//  {kCGLPFAMPSafe, "MP Safe"},

//  {kCGLPFAMultiScreen, "Multi Screen"},

//  {kCGLPFARobust, "Robust"},

#endif

};

void

gst_gl_context_cocoa_dump_pixel_format (CGLPixelFormatObj fmt)

{

  int i;

  for (i = 0; i < G_N_ELEMENTS (pixel_attrs); i++) {

    gint val;

    CGLError ret = CGLDescribePixelFormat (fmt, 0, pixel_attrs[i].attr, &val;;

    if (ret != kCGLNoError) {

      GST_WARNING ("failed to get pixel format %p attribute %s", fmt, pixel_attrs[i].attr_name);

    } else {

      GST_DEBUG ("Pixel format %p attr %s = %i", fmt, pixel_attrs[i].attr_name,

          val);

    }

  }

}

CGLPixelFormatObj

gst_gl_context_cocoa_get_pixel_format (GstGLContextCocoa *context)

{

  return context->priv->pixel_format;

}

static gboolean

gst_gl_context_cocoa_create_context (GstGLContext *context, GstGLAPI gl_api,

    GstGLContext *other_context, GError **error)

{

  GstGLContextCocoa *context_cocoa = GST_GL_CONTEXT_COCOA (context);

  GstGLContextCocoaPrivate *priv = context_cocoa->priv;

  GstGLWindow *window = gst_gl_context_get_window (context);

  GstGLWindowCocoa *window_cocoa = GST_GL_WINDOW_COCOA (window);

  GstGLAPI context_api = GST_GL_API_NONE;

  const GLint swapInterval = 1;

  CGLPixelFormatObj fmt = NULL;

  CGLContextObj glContext;

  CGLPixelFormatAttribute attribs[] = {

    kCGLPFADoubleBuffer,

    kCGLPFAAccumSize, 32,

    0

  };

  CGLError ret;

  gint pix_fmt_i = 0;

  gint npix;

  if ((gl_api & (GST_GL_API_OPENGL | GST_GL_API_OPENGL3)) == GST_GL_API_NONE) {

    g_set_error (error, GST_GL_CONTEXT_ERROR,

        GST_GL_CONTEXT_ERROR_CREATE_CONTEXT,

        "The CGL backend only supports GL and GL3");

    goto error;

  }

  priv->gl_context = nil;

  if (other_context)

    priv->external_gl_context = (CGLContextObj) gst_gl_context_get_gl_context (other_context);

  else

    priv->external_gl_context = NULL;

  if (priv->external_gl_context) {

    gint profile;

    fmt = CGLGetPixelFormat (priv->external_gl_context);

#if MAC_OS_X_VERSION_MIN_REQUIRED >= 1070

    /* core profile is only available in >= 10.7 */

    if (kCGLNoError == CGLDescribePixelFormat (fmt, 0, kCGLPFAOpenGLProfile,

          &profile)) {

      if (profile == kCGLOGLPVersion_3_2_Core) {

        context_api = GST_GL_API_OPENGL3;

      } else {

        context_api =GST_GL_API_OPENGL;

      }

    }

#else

    context_api = GST_GL_API_OPENGL;

#endif

  }

  if (!fmt) {

#if MAC_OS_X_VERSION_MIN_REQUIRED >= 1070

    if (gl_api & GST_GL_API_OPENGL3) {

      attribs[pix_fmt_i++] = kCGLPFAOpenGLProfile;

      attribs[pix_fmt_i++] = (int) kCGLOGLPVersion_3_2_Core;

      context_api = GST_GL_API_OPENGL3;

    } else {

      context_api = GST_GL_API_OPENGL;

    }

#else

    context_api = GST_GL_API_OPENGL;

#endif

    attribs[pix_fmt_i++] = 0;

    ret = CGLChoosePixelFormat (attribs, &fmt, &npix);

    if (ret != kCGLNoError) {

      g_set_error (error, GST_GL_CONTEXT_ERROR,

          GST_GL_CONTEXT_ERROR_WRONG_CONFIG, "cannot choose a pixel format: %s", CGLErrorString (ret));

      goto error;

    }

  }

  gst_gl_context_cocoa_dump_pixel_format (fmt);

  ret = CGLCreateContext (fmt, priv->external_gl_context, &glContext);

  if (ret != kCGLNoError) {

    g_set_error (error, GST_GL_CONTEXT_ERROR, GST_GL_CONTEXT_ERROR_CREATE_CONTEXT,

        "failed to create context: %s", CGLErrorString (ret));

    goto error;

  }

  context_cocoa->priv->pixel_format = fmt;

  context_cocoa->priv->gl_context = glContext;

  _invoke_on_main ((GstGLWindowCB) gst_gl_window_cocoa_create_window,

      gst_object_ref (window_cocoa), (GDestroyNotify) gst_object_unref);

  if (!context_cocoa->priv->gl_context) {

    goto error;

  }

  GST_INFO_OBJECT (context, "GL context created: %p", context_cocoa->priv->gl_context);

  CGLSetCurrentContext (context_cocoa->priv->gl_context);

  /* Back and front buffers are swapped only during the vertical retrace of the monitor.

   * Discarded if you configured your driver to Never-use-V-Sync.

   */

  CGLSetParameter (context_cocoa->priv->gl_context, kCGLCPSwapInterval, &swapInterval);

  context_cocoa->priv->context_api = context_api;

  if (window)

    gst_object_unref (window);

  return TRUE;

error:

  {

    if (window)

      gst_object_unref (window);

    return FALSE;

  }

}

static void

gst_gl_context_cocoa_swap_buffers (GstGLContext * context)

{

}

static void

gst_gl_context_cocoa_destroy_context (GstGLContext *context)

{

  /* FIXME: Need to release context and other things? */

}

static guintptr

gst_gl_context_cocoa_get_gl_context (GstGLContext * context)

{

  return (guintptr) GST_GL_CONTEXT_COCOA (context)->priv->gl_context;

}

static gboolean

gst_gl_context_cocoa_activate (GstGLContext * context, gboolean activate)

{

  GstGLContextCocoa *context_cocoa = GST_GL_CONTEXT_COCOA (context);

  gpointer context_handle = activate ? context_cocoa->priv->gl_context : NULL;

  return kCGLNoError == CGLSetCurrentContext (context_handle);

}

static GstGLAPI

gst_gl_context_cocoa_get_gl_api (GstGLContext * context)

{

  GstGLContextCocoa *context_cocoa = GST_GL_CONTEXT_COCOA (context);

  if (context_cocoa->priv->gl_context)

    return context_cocoa->priv->context_api;

  return GST_GL_API_OPENGL | GST_GL_API_OPENGL3;

}

static GstGLPlatform

gst_gl_context_cocoa_get_gl_platform (GstGLContext * context)

{

  return GST_GL_PLATFORM_CGL;

}

guintptr

gst_gl_context_cocoa_get_current_context (void)

{

  return (guintptr) CGLGetCurrentContext ();

}