/*

 * GStreamer

 * Copyright (C) 2008 Julien Isorce <julien.isorce@gmail.com>

 * 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 <gst/gst.h>

#include <gst/gl/gl.h>

#include <gst/gl/gstglfuncs.h>

#include "gstglcontext_wgl.h"

#include <GL/wglext.h>

#include "../utils/opengl_versions.h"

#include "../gstglcontext_private.h"

struct _GstGLContextWGLPrivate

{

  PFNWGLCREATECONTEXTATTRIBSARBPROC wglCreateContextAttribsARB;

  GstGLAPI context_api;

};

#define GST_CAT_DEFAULT gst_gl_context_debug

#define gst_gl_context_wgl_parent_class parent_class

G_DEFINE_TYPE (GstGLContextWGL, gst_gl_context_wgl, GST_TYPE_GL_CONTEXT);

#define GST_GL_CONTEXT_WGL_GET_PRIVATE(o) \

  (G_TYPE_INSTANCE_GET_PRIVATE((o), GST_TYPE_GL_CONTEXT_WGL, GstGLContextWGLPrivate))

static guintptr gst_gl_context_wgl_get_gl_context (GstGLContext * context);

static void gst_gl_context_wgl_swap_buffers (GstGLContext * context);

static gboolean gst_gl_context_wgl_choose_format (GstGLContext * context,

    GError ** error);

static gboolean gst_gl_context_wgl_activate (GstGLContext * context,

    gboolean activate);

static gboolean gst_gl_context_wgl_create_context (GstGLContext * context,

    GstGLAPI gl_api, GstGLContext * other_context, GError ** error);

static void gst_gl_context_wgl_destroy_context (GstGLContext * context);

GstGLAPI gst_gl_context_wgl_get_gl_api (GstGLContext * context);

static GstGLPlatform gst_gl_context_wgl_get_gl_platform (GstGLContext *

    context);

static void

gst_gl_context_wgl_class_init (GstGLContextWGLClass * klass)

{

  GstGLContextClass *context_class = (GstGLContextClass *) klass;

  g_type_class_add_private (klass, sizeof (GstGLContextWGLPrivate));

  context_class->get_gl_context =

      GST_DEBUG_FUNCPTR (gst_gl_context_wgl_get_gl_context);

  context_class->choose_format =

      GST_DEBUG_FUNCPTR (gst_gl_context_wgl_choose_format);

  context_class->activate = GST_DEBUG_FUNCPTR (gst_gl_context_wgl_activate);

  context_class->create_context =

      GST_DEBUG_FUNCPTR (gst_gl_context_wgl_create_context);

  context_class->destroy_context =

      GST_DEBUG_FUNCPTR (gst_gl_context_wgl_destroy_context);

  context_class->swap_buffers =

      GST_DEBUG_FUNCPTR (gst_gl_context_wgl_swap_buffers);

  context_class->get_proc_address =

      GST_DEBUG_FUNCPTR (gst_gl_context_wgl_get_proc_address);

  context_class->get_gl_api = GST_DEBUG_FUNCPTR (gst_gl_context_wgl_get_gl_api);

  context_class->get_gl_platform =

      GST_DEBUG_FUNCPTR (gst_gl_context_wgl_get_gl_platform);

}

static void

gst_gl_context_wgl_init (GstGLContextWGL * context_wgl)

{

  context_wgl->priv = GST_GL_CONTEXT_WGL_GET_PRIVATE (context_wgl);

  context_wgl->priv->context_api = GST_GL_API_OPENGL | GST_GL_API_OPENGL3;

}

/* Must be called in the gl thread */

GstGLContextWGL *

gst_gl_context_wgl_new (GstGLDisplay * display)

{

  GstGLContextWGL *context;

  if ((gst_gl_display_get_handle_type (display) & GST_GL_DISPLAY_TYPE_WIN32) ==

      0)

    /* we require an win32 display handle to create WGL contexts */

    return NULL;

  context = g_object_new (GST_TYPE_GL_CONTEXT_WGL, NULL);

  gst_object_ref_sink (context);

  return context;

}

static HGLRC

_create_context_with_flags (GstGLContextWGL * context_wgl, HDC dpy,

    HGLRC share_context, gint major, gint minor, gint contextFlags,

    gint profileMask)

{

  HGLRC ret;

#define N_ATTRIBS 20

  gint attribs[N_ATTRIBS];

  gint n = 0;

  if (major) {

    attribs[n++] = WGL_CONTEXT_MAJOR_VERSION_ARB;

    attribs[n++] = major;

  }

  if (minor) {

    attribs[n++] = WGL_CONTEXT_MINOR_VERSION_ARB;

    attribs[n++] = minor;

  }

  if (contextFlags) {

    attribs[n++] = WGL_CONTEXT_FLAGS_ARB;

    attribs[n++] = contextFlags;

  }

  if (profileMask) {

    attribs[n++] = WGL_CONTEXT_PROFILE_MASK_ARB;

    attribs[n++] = profileMask;

  }

  attribs[n++] = 0;

  g_assert (n < N_ATTRIBS);

#undef N_ATTRIBS

  ret =

      context_wgl->priv->wglCreateContextAttribsARB (dpy, share_context,

      attribs);

  return ret;

}

static gboolean

gst_gl_context_wgl_create_context (GstGLContext * context,

    GstGLAPI gl_api, GstGLContext * other_context, GError ** error)

{

  GstGLWindow *window;

  GstGLContextWGL *context_wgl;

  HGLRC external_gl_context = NULL;

  HGLRC trampoline;

  HDC device;

  context_wgl = GST_GL_CONTEXT_WGL (context);

  window = gst_gl_context_get_window (context);

  device = (HDC) gst_gl_window_get_display (window);

  if (other_context) {

    if (gst_gl_context_get_gl_platform (other_context) != GST_GL_PLATFORM_WGL) {

      g_set_error (error, GST_GL_CONTEXT_ERROR,

          GST_GL_CONTEXT_ERROR_WRONG_CONFIG,

          "Cannot share context with a non-WGL context");

      goto failure;

    }

    external_gl_context = (HGLRC) gst_gl_context_get_gl_context (other_context);

  }

  trampoline = wglCreateContext (device);

  if (trampoline)

    GST_DEBUG ("gl context created: %" G_GUINTPTR_FORMAT,

        (guintptr) trampoline);

  else {

    g_set_error (error, GST_GL_CONTEXT_ERROR,

        GST_GL_CONTEXT_ERROR_CREATE_CONTEXT, "failed to create glcontext:0x%x",

        (unsigned int) GetLastError ());

    goto failure;

  }

  g_assert (trampoline);

  /* get extension functions */

  wglMakeCurrent (device, trampoline);

  context_wgl->priv->wglCreateContextAttribsARB =

      (PFNWGLCREATECONTEXTATTRIBSARBPROC)

      wglGetProcAddress ("wglCreateContextAttribsARB");

  wglMakeCurrent (device, 0);

  wglDeleteContext (trampoline);

  trampoline = NULL;

  if (context_wgl->priv->wglCreateContextAttribsARB != NULL

      && gl_api & GST_GL_API_OPENGL3) {

    gint i;

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

      gint profileMask = 0;

      gint contextFlags = 0;

      if ((opengl_versions[i].major > 3

              || (opengl_versions[i].major == 3

                  && opengl_versions[i].minor >= 2))) {

        profileMask |= WGL_CONTEXT_CORE_PROFILE_BIT_ARB;

        contextFlags |= WGL_CONTEXT_DEBUG_BIT_ARB;

      } else {

        break;

      }

      GST_DEBUG_OBJECT (context, "trying to create a GL %d.%d context",

          opengl_versions[i].major, opengl_versions[i].minor);

      context_wgl->wgl_context = _create_context_with_flags (context_wgl,

          device, external_gl_context, opengl_versions[i].major,

          opengl_versions[i].minor, contextFlags, profileMask);

      if (context_wgl->wgl_context) {

        context_wgl->priv->context_api = GST_GL_API_OPENGL3;

        break;

      }

    }

  }

  if (!context_wgl->wgl_context) {

    if (context_wgl->priv->wglCreateContextAttribsARB && external_gl_context) {

      context_wgl->wgl_context =

          context_wgl->priv->wglCreateContextAttribsARB (device,

          external_gl_context, 0);

    }

    if (!context_wgl->wgl_context) {

      context_wgl->wgl_context = wglCreateContext (device);

      if (!context_wgl->wgl_context) {

        g_set_error (error, GST_GL_CONTEXT_ERROR,

            GST_GL_CONTEXT_ERROR_CREATE_CONTEXT,

            "Failed to create WGL context 0x%x",

            (unsigned int) GetLastError ());

        goto failure;

      }

      if (external_gl_context) {

        if (!wglShareLists (external_gl_context, context_wgl->wgl_context)) {

          g_set_error (error, GST_GL_CONTEXT_ERROR,

              GST_GL_CONTEXT_ERROR_CREATE_CONTEXT,

              "failed to share contexts through wglShareLists 0x%x",

              (unsigned int) GetLastError ());

          goto failure;

        }

      }

    }

    context_wgl->priv->context_api = GST_GL_API_OPENGL;

  }

  GST_LOG ("gl context id: %" G_GUINTPTR_FORMAT,

      (guintptr) context_wgl->wgl_context);

  gst_object_unref (window);

  return TRUE;

failure:

  gst_object_unref (window);

  return FALSE;

}

static void

gst_gl_context_wgl_destroy_context (GstGLContext * context)

{

  GstGLContextWGL *context_wgl;

  context_wgl = GST_GL_CONTEXT_WGL (context);

  if (context_wgl->wgl_context)

    wglDeleteContext (context_wgl->wgl_context);

  context_wgl->wgl_context = NULL;

}

static gboolean

gst_gl_context_wgl_choose_format (GstGLContext * context, GError ** error)

{

  GstGLWindow *window;

  PIXELFORMATDESCRIPTOR pfd;

  gint pixelformat = 0;

  gboolean res = FALSE;

  HDC device;

  window = gst_gl_context_get_window (context);

  gst_gl_window_win32_create_window (GST_GL_WINDOW_WIN32 (window), error);

  device = (HDC) gst_gl_window_get_display (window);

  gst_object_unref (window);

  pfd.nSize = sizeof (PIXELFORMATDESCRIPTOR);

  pfd.nVersion = 1;

  pfd.dwFlags = PFD_DRAW_TO_WINDOW | PFD_SUPPORT_OPENGL | PFD_DOUBLEBUFFER;

  pfd.iPixelType = PFD_TYPE_RGBA;

  pfd.cColorBits = 24;

  pfd.cRedBits = 8;

  pfd.cRedShift = 0;

  pfd.cGreenBits = 8;

  pfd.cGreenShift = 0;

  pfd.cBlueBits = 8;

  pfd.cBlueShift = 0;

  pfd.cAlphaBits = 0;

  pfd.cAlphaShift = 0;

  pfd.cAccumBits = 0;

  pfd.cAccumRedBits = 0;

  pfd.cAccumGreenBits = 0;

  pfd.cAccumBlueBits = 0;

  pfd.cAccumAlphaBits = 0;

  pfd.cDepthBits = 24;

  pfd.cStencilBits = 8;

  pfd.cAuxBuffers = 0;

  pfd.iLayerType = PFD_MAIN_PLANE;

  pfd.bReserved = 0;

  pfd.dwLayerMask = 0;

  pfd.dwVisibleMask = 0;

  pfd.dwDamageMask = 0;

  pfd.cColorBits = (BYTE) GetDeviceCaps (device, BITSPIXEL);

  pixelformat = ChoosePixelFormat (device, &pfd;;

  if (!pixelformat) {

    g_set_error (error, GST_GL_CONTEXT_ERROR, GST_GL_CONTEXT_ERROR_FAILED,

        "Failed to choose a pixel format");

    return FALSE;

  }

  res = SetPixelFormat (device, pixelformat, &pfd;;

  return res;

}

static void

gst_gl_context_wgl_swap_buffers (GstGLContext * context)

{

  GstGLWindow *window = gst_gl_context_get_window (context);

  HDC device = (HDC) gst_gl_window_get_display (window);

  SwapBuffers (device);

  gst_object_unref (window);

}

static guintptr

gst_gl_context_wgl_get_gl_context (GstGLContext * context)

{

  return (guintptr) GST_GL_CONTEXT_WGL (context)->wgl_context;

}

static gboolean

gst_gl_context_wgl_activate (GstGLContext * context, gboolean activate)

{

  GstGLWindow *window;

  GstGLContextWGL *context_wgl;

  HDC device;

  gboolean result;

  window = gst_gl_context_get_window (context);

  context_wgl = GST_GL_CONTEXT_WGL (context);

  device = (HDC) gst_gl_window_get_display (window);

  if (activate) {

    result = wglMakeCurrent (device, context_wgl->wgl_context);

  } else {

    result = wglMakeCurrent (NULL, NULL);

  }

  gst_object_unref (window);

  return result;

}

GstGLAPI

gst_gl_context_wgl_get_gl_api (GstGLContext * context)

{

  GstGLContextWGL *context_wgl = GST_GL_CONTEXT_WGL (context);

  return context_wgl->priv->context_api;

}

static GstGLPlatform

gst_gl_context_wgl_get_gl_platform (GstGLContext * context)

{

  return GST_GL_PLATFORM_WGL;

}

gpointer

gst_gl_context_wgl_get_proc_address (GstGLAPI gl_api, const gchar * name)

{

  gpointer result;

  if (!(result = gst_gl_context_default_get_proc_address (gl_api, name))) {

    result = wglGetProcAddress ((LPCSTR) name);

  }

  return result;

}

guintptr

gst_gl_context_wgl_get_current_context (void)

{

  return (guintptr) wglGetCurrentContext ();

}