/*

  Simple DirectMedia Layer

  Copyright (C) 1997-2013 Sam Lantinga <slouken@libsdl.org>

  This software is provided 'as-is', without any express or implied

  warranty.  In no event will the authors be held liable for any damages

  arising from the use of this software.

  Permission is granted to anyone to use this software for any purpose,

  including commercial applications, and to alter it and redistribute it

  freely, subject to the following restrictions:

  1. The origin of this software must not be misrepresented; you must not

     claim that you wrote the original software. If you use this software

     in a product, an acknowledgment in the product documentation would be

     appreciated but is not required.

  2. Altered source versions must be plainly marked as such, and must not be

     misrepresented as being the original software.

  3. This notice may not be removed or altered from any source distribution.

*/

#include "SDL_config.h"

/* NSOpenGL implementation of SDL OpenGL support */

#if SDL_VIDEO_OPENGL_CGL

#include "SDL_cocoavideo.h"

#include "SDL_cocoaopengl.h"

#include <OpenGL/CGLTypes.h>

#include <OpenGL/OpenGL.h>

#include <OpenGL/CGLRenderers.h>

#include "SDL_loadso.h"

#include "SDL_opengl.h"

#define DEFAULT_OPENGL  "/System/Library/Frameworks/OpenGL.framework/Libraries/libGL.dylib"

#ifndef kCGLPFAOpenGLProfile

#define kCGLPFAOpenGLProfile 99

#endif

#ifndef kCGLOGLPVersion_Legacy

#define kCGLOGLPVersion_Legacy 0x1000

#endif

#ifndef kCGLOGLPVersion_3_2_Core

#define kCGLOGLPVersion_3_2_Core 0x3200

#endif

@implementation SDLOpenGLContext : NSOpenGLContext

- (id)initWithFormat:(NSOpenGLPixelFormat *)format

        shareContext:(NSOpenGLContext *)share

{

    SDL_AtomicSet(&self->dirty, 0);

    return [super initWithFormat:format shareContext:share];

}

- (void)scheduleUpdate

{

    SDL_AtomicAdd(&self->dirty, 1);

}

/* This should only be called on the thread on which a user is using the context. */

- (void)updateIfNeeded

{

    int value = SDL_AtomicSet(&self->dirty, 0);

    if (value > 0) {

        /* We call the real underlying update here, since -[SDLOpenGLContext update] just calls us. */

        [super update];

    }

}

/* This should only be called on the thread on which a user is using the context. */

- (void)update

{

    /* This ensures that regular 'update' calls clear the atomic dirty flag. */

    [self scheduleUpdate];

    [self updateIfNeeded];

}

@end

int

Cocoa_GL_LoadLibrary(_THIS, const char *path)

{

    /* Load the OpenGL library */

    if (path == NULL) {

        path = SDL_getenv("SDL_OPENGL_LIBRARY");

    }

    if (path == NULL) {

        path = DEFAULT_OPENGL;

    }

    _this->gl_config.dll_handle = SDL_LoadObject(path);

    if (!_this->gl_config.dll_handle) {

        return -1;

    }

    SDL_strlcpy(_this->gl_config.driver_path, path,

                SDL_arraysize(_this->gl_config.driver_path));

    return 0;

}

void *

Cocoa_GL_GetProcAddress(_THIS, const char *proc)

{

    return SDL_LoadFunction(_this->gl_config.dll_handle, proc);

}

void

Cocoa_GL_UnloadLibrary(_THIS)

{

    SDL_UnloadObject(_this->gl_config.dll_handle);

    _this->gl_config.dll_handle = NULL;

}

SDL_GLContext

Cocoa_GL_CreateContext(_THIS, SDL_Window * window)

{

    const int wantver = (_this->gl_config.major_version << 8) |

                        (_this->gl_config.minor_version);

    SDL_VideoData *data = (SDL_VideoData *) _this->driverdata;

    NSAutoreleasePool *pool;

    SDL_VideoDisplay *display = SDL_GetDisplayForWindow(window);

    SDL_DisplayData *displaydata = (SDL_DisplayData *)display->driverdata;

    NSOpenGLPixelFormatAttribute attr[32];

    NSOpenGLPixelFormat *fmt;

    SDLOpenGLContext *context;

    NSOpenGLContext *share_context = nil;

    int i = 0;

    if (_this->gl_config.profile_mask == SDL_GL_CONTEXT_PROFILE_ES) {

        SDL_SetError ("OpenGL ES not supported on this platform");

        return NULL;

    }

    /* Sadly, we'll have to update this as life progresses, since we need to

       set an enum for context profiles, not a context version number */

    if (wantver > 0x0302) {

        SDL_SetError ("OpenGL > 3.2 is not supported on this platform");

        return NULL;

    }

    pool = [[NSAutoreleasePool alloc] init];

    /* specify a profile if we're on Lion (10.7) or later. */

    if (data->osversion >= 0x1070) {

        NSOpenGLPixelFormatAttribute profile = kCGLOGLPVersion_Legacy;

        if (_this->gl_config.profile_mask == SDL_GL_CONTEXT_PROFILE_CORE) {

            if (wantver == 0x0302) {

                profile = kCGLOGLPVersion_3_2_Core;

            }

        }

        attr[i++] = kCGLPFAOpenGLProfile;

        attr[i++] = profile;

    }

    attr[i++] = NSOpenGLPFAColorSize;

    attr[i++] = SDL_BYTESPERPIXEL(display->current_mode.format)*8;

    attr[i++] = NSOpenGLPFADepthSize;

    attr[i++] = _this->gl_config.depth_size;

    if (_this->gl_config.double_buffer) {

        attr[i++] = NSOpenGLPFADoubleBuffer;

    }

    if (_this->gl_config.stereo) {

        attr[i++] = NSOpenGLPFAStereo;

    }

    if (_this->gl_config.stencil_size) {

        attr[i++] = NSOpenGLPFAStencilSize;

        attr[i++] = _this->gl_config.stencil_size;

    }

    if ((_this->gl_config.accum_red_size +

         _this->gl_config.accum_green_size +

         _this->gl_config.accum_blue_size +

         _this->gl_config.accum_alpha_size) > 0) {

        attr[i++] = NSOpenGLPFAAccumSize;

        attr[i++] = _this->gl_config.accum_red_size + _this->gl_config.accum_green_size + _this->gl_config.accum_blue_size + _this->gl_config.accum_alpha_size;

    }

    if (_this->gl_config.multisamplebuffers) {

        attr[i++] = NSOpenGLPFASampleBuffers;

        attr[i++] = _this->gl_config.multisamplebuffers;

    }

    if (_this->gl_config.multisamplesamples) {

        attr[i++] = NSOpenGLPFASamples;

        attr[i++] = _this->gl_config.multisamplesamples;

        attr[i++] = NSOpenGLPFANoRecovery;

    }

    if (_this->gl_config.accelerated >= 0) {

        if (_this->gl_config.accelerated) {

            attr[i++] = NSOpenGLPFAAccelerated;

        } else {

            attr[i++] = NSOpenGLPFARendererID;

            attr[i++] = kCGLRendererGenericFloatID;

        }

    }

    attr[i++] = NSOpenGLPFAScreenMask;

    attr[i++] = CGDisplayIDToOpenGLDisplayMask(displaydata->display);

    attr[i] = 0;

    fmt = [[NSOpenGLPixelFormat alloc] initWithAttributes:attr];

    if (fmt == nil) {

        SDL_SetError ("Failed creating OpenGL pixel format");

        [pool release];

        return NULL;

    }

    if (_this->gl_config.share_with_current_context) {

        share_context = (NSOpenGLContext*)SDL_GL_GetCurrentContext();

    }

    context = [[SDLOpenGLContext alloc] initWithFormat:fmt shareContext:share_context];

    [fmt release];

    if (context == nil) {

        SDL_SetError ("Failed creating OpenGL context");

        [pool release];

        return NULL;

    }

    [pool release];

    if ( Cocoa_GL_MakeCurrent(_this, window, context) < 0 ) {

        Cocoa_GL_DeleteContext(_this, context);

        return NULL;

    }

    return context;

}

int

Cocoa_GL_MakeCurrent(_THIS, SDL_Window * window, SDL_GLContext context)

{

    NSAutoreleasePool *pool;

    pool = [[NSAutoreleasePool alloc] init];

    if (context) {

        SDL_WindowData *windowdata = (SDL_WindowData *)window->driverdata;

        SDLOpenGLContext *nscontext = (SDLOpenGLContext *)context;

        windowdata->nscontext = nscontext;

        if ([nscontext view] != [windowdata->nswindow contentView]) {

            [nscontext setView:[windowdata->nswindow contentView]];

            [nscontext scheduleUpdate];

        }

        [nscontext updateIfNeeded];

        [nscontext makeCurrentContext];

    } else {

        [NSOpenGLContext clearCurrentContext];

    }

    [pool release];

    return 0;

}

int

Cocoa_GL_SetSwapInterval(_THIS, int interval)

{

    NSAutoreleasePool *pool;

    NSOpenGLContext *nscontext;

    GLint value;

    int status;

    pool = [[NSAutoreleasePool alloc] init];

    nscontext = (NSOpenGLContext*)SDL_GL_GetCurrentContext();

    if (nscontext != nil) {

        value = interval;

        [nscontext setValues:&value forParameter:NSOpenGLCPSwapInterval];

        status = 0;

    } else {

        status = SDL_SetError("No current OpenGL context");

    }

    [pool release];

    return status;

}

int

Cocoa_GL_GetSwapInterval(_THIS)

{

    NSAutoreleasePool *pool;

    NSOpenGLContext *nscontext;

    GLint value;

    int status = 0;

    pool = [[NSAutoreleasePool alloc] init];

    nscontext = (NSOpenGLContext*)SDL_GL_GetCurrentContext();

    if (nscontext != nil) {

        [nscontext getValues:&value forParameter:NSOpenGLCPSwapInterval];

        status = (int)value;

    }

    [pool release];

    return status;

}

void

Cocoa_GL_SwapWindow(_THIS, SDL_Window * window)

{

    NSAutoreleasePool *pool;

    SDL_WindowData *windowdata = (SDL_WindowData *)window->driverdata;

    SDLOpenGLContext *nscontext = windowdata->nscontext;

    pool = [[NSAutoreleasePool alloc] init];

    [nscontext flushBuffer];

    [nscontext updateIfNeeded];

    [pool release];

}

void

Cocoa_GL_DeleteContext(_THIS, SDL_GLContext context)

{

    NSAutoreleasePool *pool;

    NSOpenGLContext *nscontext = (NSOpenGLContext *)context;

    pool = [[NSAutoreleasePool alloc] init];

    [nscontext clearDrawable];

    [nscontext release];

    [pool release];

}

#endif /* SDL_VIDEO_OPENGL_CGL */

/* vi: set ts=4 sw=4 expandtab: */