/*
 * Copyright (C) 2011 Google Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1.  Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 * 2.  Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in the
 *     documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#ifndef Extensions3D_h
#define Extensions3D_h

#include "GraphicsTypes3D.h"

#include <wtf/text/WTFString.h>

namespace WebCore {

// This is a base class containing only pure virtual functions.
// Implementations must provide a subclass.
//
// The supported extensions are defined below and in subclasses,
// possibly platform-specific ones.
//
// Calling any extension function not supported by the current context
// must be a no-op; in particular, it may not have side effects. In
// this situation, if the function has a return value, 0 is returned.
class Extensions3D {
public:
    virtual ~Extensions3D() {}

    // Supported extensions:
    //   GL_EXT_texture_format_BGRA8888
    //   GL_EXT_read_format_bgra
    //   GL_ARB_robustness
    //   GL_ARB_texture_non_power_of_two / GL_OES_texture_npot
    //   GL_EXT_packed_depth_stencil / GL_OES_packed_depth_stencil
    //   GL_ANGLE_framebuffer_blit / GL_ANGLE_framebuffer_multisample
    //   GL_OES_texture_float
    //   GL_OES_standard_derivatives
    //   GL_OES_rgb8_rgba8
    //   GL_OES_vertex_array_object
    //   GL_ANGLE_translated_shader_source
    //   GL_ARB_texture_rectangle (only the subset required to
    //     implement IOSurface binding; it's recommended to support
    //     this only on Mac OS X to limit the amount of code dependent
    //     on this extension)
    //   GL_EXT_texture_compression_dxt1
    //   GL_EXT_texture_compression_s3tc
    //   GL_OES_compressed_ETC1_RGB8_texture
    //   GL_IMG_texture_compression_pvrtc

    // Takes full name of extension; for example,
    // "GL_EXT_texture_format_BGRA8888".
    virtual bool supports(const String&) = 0;

    // Certain OpenGL and WebGL implementations may support enabling
    // extensions lazily. This method may only be called with
    // extension names for which supports returns true.
    virtual void ensureEnabled(const String&) = 0;

    // Takes full name of extension: for example, "GL_EXT_texture_format_BGRA8888".
    // Checks to see whether the given extension is actually enabled (see ensureEnabled).
    // Has no other side-effects.
    virtual bool isEnabled(const String&) = 0;

    enum ExtensionsEnumType {
        // GL_EXT_texture_format_BGRA8888 enums
        BGRA_EXT = 0x80E1,

        // GL_ARB_robustness enums
        GUILTY_CONTEXT_RESET_ARB = 0x8253,
        INNOCENT_CONTEXT_RESET_ARB = 0x8254,
        UNKNOWN_CONTEXT_RESET_ARB = 0x8255,

        // GL_EXT/OES_packed_depth_stencil enums
        DEPTH24_STENCIL8 = 0x88F0,
        
        // GL_ANGLE_framebuffer_blit names
        READ_FRAMEBUFFER = 0x8CA8,
        DRAW_FRAMEBUFFER = 0x8CA9,
        DRAW_FRAMEBUFFER_BINDING = 0x8CA6, 
        READ_FRAMEBUFFER_BINDING = 0x8CAA,
        
        // GL_ANGLE_framebuffer_multisample names
        RENDERBUFFER_SAMPLES = 0x8CAB,
        FRAMEBUFFER_INCOMPLETE_MULTISAMPLE = 0x8D56,
        MAX_SAMPLES = 0x8D57,

        // GL_OES_standard_derivatives names
        FRAGMENT_SHADER_DERIVATIVE_HINT_OES = 0x8B8B,

        // GL_OES_rgb8_rgba8 names
        RGB8_OES = 0x8051,
        RGBA8_OES = 0x8058,
        
        // GL_OES_vertex_array_object names
        VERTEX_ARRAY_BINDING_OES = 0x85B5,

        // GL_ANGLE_translated_shader_source
        TRANSLATED_SHADER_SOURCE_LENGTH_ANGLE = 0x93A0,

        // GL_ARB_texture_rectangle
        TEXTURE_RECTANGLE_ARB =  0x84F5,
        TEXTURE_BINDING_RECTANGLE_ARB = 0x84F6,

        // GL_EXT_texture_compression_dxt1
        // GL_EXT_texture_compression_s3tc
        COMPRESSED_RGB_S3TC_DXT1_EXT = 0x83F0,
        COMPRESSED_RGBA_S3TC_DXT1_EXT = 0x83F1,
        COMPRESSED_RGBA_S3TC_DXT3_EXT = 0x83F2,
        COMPRESSED_RGBA_S3TC_DXT5_EXT = 0x83F3,

        // GL_OES_compressed_ETC1_RGB8_texture
        ETC1_RGB8_OES = 0x8D64,

        // GL_IMG_texture_compression_pvrtc
        COMPRESSED_RGB_PVRTC_4BPPV1_IMG = 0x8C00,
        COMPRESSED_RGB_PVRTC_2BPPV1_IMG = 0x8C01,
        COMPRESSED_RGBA_PVRTC_4BPPV1_IMG = 0x8C02,
        COMPRESSED_RGBA_PVRTC_2BPPV1_IMG = 0x8C03,
    };

    // GL_ARB_robustness
    // Note: This method's behavior differs from the GL_ARB_robustness
    // specification in the following way:
    // The implementation must not reset the error state during this call.
    // If getGraphicsResetStatusARB returns an error, it should continue
    // returning the same error. Restoring the GraphicsContext3D is handled
    // externally.
    virtual int getGraphicsResetStatusARB() = 0;
    
    // GL_ANGLE_framebuffer_blit
    virtual void blitFramebuffer(long srcX0, long srcY0, long srcX1, long srcY1, long dstX0, long dstY0, long dstX1, long dstY1, unsigned long mask, unsigned long filter) = 0;
    
    // GL_ANGLE_framebuffer_multisample
    virtual void renderbufferStorageMultisample(unsigned long target, unsigned long samples, unsigned long internalformat, unsigned long width, unsigned long height) = 0;
    
    // GL_OES_vertex_array_object
    virtual Platform3DObject createVertexArrayOES() = 0;
    virtual void deleteVertexArrayOES(Platform3DObject) = 0;
    virtual GC3Dboolean isVertexArrayOES(Platform3DObject) = 0;
    virtual void bindVertexArrayOES(Platform3DObject) = 0;

    // GL_ANGLE_translated_shader_source
    virtual String getTranslatedShaderSourceANGLE(Platform3DObject) = 0;
};

} // namespace WebCore

#endif // Extensions3D_h
