/*

 * Copyright (C) 2010 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:

 *

 *     * Redistributions of source code must retain the above copyright

 * notice, this list of conditions and the following disclaimer.

 *     * 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.

 *     * Neither the name of Google Inc. nor the names of its

 * contributors may be used to endorse or promote products derived from

 * this software without specific prior written permission.

 *

 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND 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 THE COPYRIGHT

 * OWNER OR 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 WebGraphicsContext3DDefaultImpl_h

#define WebGraphicsContext3DDefaultImpl_h

#if ENABLE(3D_CANVAS)

#include "WebGraphicsContext3D.h"

#include <wtf/ListHashSet.h>

#if OS(WINDOWS)

#include <windows.h>

#endif

#include "GL/glew.h"

#if OS(WINDOWS)

#include "GL/wglew.h"

#endif

#if PLATFORM(CG)

#include <OpenGL/OpenGL.h>

#else

#define FLIP_FRAMEBUFFER_VERTICALLY

#endif

#if OS(LINUX)

#include "GL/glxew.h"

#endif

namespace WebKit {

// The default implementation of WebGL. In Chromium, using this class

// requires the sandbox to be disabled, which is strongly discouraged.

// It is provided for support of test_shell and any Chromium ports

// where an in-renderer WebGL implementation would be helpful.

class WebGraphicsContext3DDefaultImpl : public WebGraphicsContext3D {

public:

    WebGraphicsContext3DDefaultImpl();

    virtual ~WebGraphicsContext3DDefaultImpl();

    //----------------------------------------------------------------------

    // WebGraphicsContext3D methods

    virtual bool initialize(WebGraphicsContext3D::Attributes attributes, WebView*);

    virtual bool makeContextCurrent();

    virtual int width();

    virtual int height();

    virtual int sizeInBytes(int type);

    virtual bool isGLES2Compliant();

    virtual void reshape(int width, int height);

    virtual bool readBackFramebuffer(unsigned char* pixels, size_t bufferSize);

    virtual unsigned int getPlatformTextureId();

    virtual void prepareTexture();

    virtual void synthesizeGLError(unsigned long error);

    virtual void activeTexture(unsigned long texture);

    virtual void attachShader(WebGLId program, WebGLId shader);

    virtual void bindAttribLocation(WebGLId program, unsigned long index, const char* name);

    virtual void bindBuffer(unsigned long target, WebGLId buffer);

    virtual void bindFramebuffer(unsigned long target, WebGLId framebuffer);

    virtual void bindRenderbuffer(unsigned long target, WebGLId renderbuffer);

    virtual void bindTexture(unsigned long target, WebGLId texture);

    virtual void blendColor(double red, double green, double blue, double alpha);

    virtual void blendEquation(unsigned long mode);

    virtual void blendEquationSeparate(unsigned long modeRGB, unsigned long modeAlpha);

    virtual void blendFunc(unsigned long sfactor, unsigned long dfactor);

    virtual void blendFuncSeparate(unsigned long srcRGB, unsigned long dstRGB, unsigned long srcAlpha, unsigned long dstAlpha);

    virtual void bufferData(unsigned long target, int size, const void* data, unsigned long usage);

    virtual void bufferSubData(unsigned long target, long offset, int size, const void* data);

    virtual unsigned long checkFramebufferStatus(unsigned long target);

    virtual void clear(unsigned long mask);

    virtual void clearColor(double red, double green, double blue, double alpha);

    virtual void clearDepth(double depth);

    virtual void clearStencil(long s);

    virtual void colorMask(bool red, bool green, bool blue, bool alpha);

    virtual void compileShader(WebGLId shader);

    virtual void copyTexImage2D(unsigned long target, long level, unsigned long internalformat, long x, long y, unsigned long width, unsigned long height, long border);

    virtual void copyTexSubImage2D(unsigned long target, long level, long xoffset, long yoffset, long x, long y, unsigned long width, unsigned long height);

    virtual void cullFace(unsigned long mode);

    virtual void depthFunc(unsigned long func);

    virtual void depthMask(bool flag);

    virtual void depthRange(double zNear, double zFar);

    virtual void detachShader(WebGLId program, WebGLId shader);

    virtual void disable(unsigned long cap);

    virtual void disableVertexAttribArray(unsigned long index);

    virtual void drawArrays(unsigned long mode, long first, long count);

    virtual void drawElements(unsigned long mode, unsigned long count, unsigned long type, long offset);

    virtual void enable(unsigned long cap);

    virtual void enableVertexAttribArray(unsigned long index);

    virtual void finish();

    virtual void flush();

    virtual void framebufferRenderbuffer(unsigned long target, unsigned long attachment, unsigned long renderbuffertarget, WebGLId renderbuffer);

    virtual void framebufferTexture2D(unsigned long target, unsigned long attachment, unsigned long textarget, WebGLId texture, long level);

    virtual void frontFace(unsigned long mode);

    virtual void generateMipmap(unsigned long target);

    virtual bool getActiveAttrib(WebGLId program, unsigned long index, ActiveInfo&);

    virtual bool getActiveUniform(WebGLId program, unsigned long index, ActiveInfo&);

    virtual void getAttachedShaders(WebGLId program, int maxCount, int* count, unsigned int* shaders);

    virtual int  getAttribLocation(WebGLId program, const char* name);

    virtual void getBooleanv(unsigned long pname, unsigned char* value);

    virtual void getBufferParameteriv(unsigned long target, unsigned long pname, int* value);

    virtual Attributes getContextAttributes();

    virtual unsigned long getError();

    virtual void getFloatv(unsigned long pname, float* value);

    virtual void getFramebufferAttachmentParameteriv(unsigned long target, unsigned long attachment, unsigned long pname, int* value);

    virtual void getIntegerv(unsigned long pname, int* value);

    virtual void getProgramiv(WebGLId program, unsigned long pname, int* value);

    virtual WebString getProgramInfoLog(WebGLId program);

    virtual void getRenderbufferParameteriv(unsigned long target, unsigned long pname, int* value);

    virtual void getShaderiv(WebGLId shader, unsigned long pname, int* value);

    virtual WebString getShaderInfoLog(WebGLId shader);

    // TBD

    // void glGetShaderPrecisionFormat (GLenum shadertype, GLenum precisiontype, GLint* range, GLint* precision);

    virtual WebString getShaderSource(WebGLId shader);

    virtual WebString getString(unsigned long name);

    virtual void getTexParameterfv(unsigned long target, unsigned long pname, float* value);

    virtual void getTexParameteriv(unsigned long target, unsigned long pname, int* value);

    virtual void getUniformfv(WebGLId program, long location, float* value);

    virtual void getUniformiv(WebGLId program, long location, int* value);

    virtual long getUniformLocation(WebGLId program, const char* name);

    virtual void getVertexAttribfv(unsigned long index, unsigned long pname, float* value);

    virtual void getVertexAttribiv(unsigned long index, unsigned long pname, int* value);

    virtual long getVertexAttribOffset(unsigned long index, unsigned long pname);

    virtual void hint(unsigned long target, unsigned long mode);

    virtual bool isBuffer(WebGLId buffer);

    virtual bool isEnabled(unsigned long cap);

    virtual bool isFramebuffer(WebGLId framebuffer);

    virtual bool isProgram(WebGLId program);

    virtual bool isRenderbuffer(WebGLId renderbuffer);

    virtual bool isShader(WebGLId shader);

    virtual bool isTexture(WebGLId texture);

    virtual void lineWidth(double);

    virtual void linkProgram(WebGLId program);

    virtual void pixelStorei(unsigned long pname, long param);

    virtual void polygonOffset(double factor, double units);

    virtual void readPixels(long x, long y, unsigned long width, unsigned long height, unsigned long format, unsigned long type, void* pixels);

    virtual void releaseShaderCompiler();

    virtual void renderbufferStorage(unsigned long target, unsigned long internalformat, unsigned long width, unsigned long height);

    virtual void sampleCoverage(double value, bool invert);

    virtual void scissor(long x, long y, unsigned long width, unsigned long height);

    virtual void shaderSource(WebGLId shader, const char* string);

    virtual void stencilFunc(unsigned long func, long ref, unsigned long mask);

    virtual void stencilFuncSeparate(unsigned long face, unsigned long func, long ref, unsigned long mask);

    virtual void stencilMask(unsigned long mask);

    virtual void stencilMaskSeparate(unsigned long face, unsigned long mask);

    virtual void stencilOp(unsigned long fail, unsigned long zfail, unsigned long zpass);

    virtual void stencilOpSeparate(unsigned long face, unsigned long fail, unsigned long zfail, unsigned long zpass);

    virtual void texImage2D(unsigned target, unsigned level, unsigned internalformat, unsigned width, unsigned height, unsigned border, unsigned format, unsigned type, const void* pixels);

    virtual void texParameterf(unsigned target, unsigned pname, float param);

    virtual void texParameteri(unsigned target, unsigned pname, int param);

    virtual void texSubImage2D(unsigned target, unsigned level, unsigned xoffset, unsigned yoffset, unsigned width, unsigned height, unsigned format, unsigned type, const void* pixels);

    virtual void uniform1f(long location, float x);

    virtual void uniform1fv(long location, int count, float* v);

    virtual void uniform1i(long location, int x);

    virtual void uniform1iv(long location, int count, int* v);

    virtual void uniform2f(long location, float x, float y);

    virtual void uniform2fv(long location, int count, float* v);

    virtual void uniform2i(long location, int x, int y);

    virtual void uniform2iv(long location, int count, int* v);

    virtual void uniform3f(long location, float x, float y, float z);

    virtual void uniform3fv(long location, int count, float* v);

    virtual void uniform3i(long location, int x, int y, int z);

    virtual void uniform3iv(long location, int count, int* v);

    virtual void uniform4f(long location, float x, float y, float z, float w);

    virtual void uniform4fv(long location, int count, float* v);

    virtual void uniform4i(long location, int x, int y, int z, int w);

    virtual void uniform4iv(long location, int count, int* v);

    virtual void uniformMatrix2fv(long location, int count, bool transpose, const float* value);

    virtual void uniformMatrix3fv(long location, int count, bool transpose, const float* value);

    virtual void uniformMatrix4fv(long location, int count, bool transpose, const float* value);

    virtual void useProgram(WebGLId program);

    virtual void validateProgram(WebGLId program);

    virtual void vertexAttrib1f(unsigned long indx, float x);

    virtual void vertexAttrib1fv(unsigned long indx, const float* values);

    virtual void vertexAttrib2f(unsigned long indx, float x, float y);

    virtual void vertexAttrib2fv(unsigned long indx, const float* values);

    virtual void vertexAttrib3f(unsigned long indx, float x, float y, float z);

    virtual void vertexAttrib3fv(unsigned long indx, const float* values);

    virtual void vertexAttrib4f(unsigned long indx, float x, float y, float z, float w);

    virtual void vertexAttrib4fv(unsigned long indx, const float* values);

    virtual void vertexAttribPointer(unsigned long indx, int size, int type, bool normalized,

                                     unsigned long stride, unsigned long offset);

    virtual void viewport(long x, long y, unsigned long width, unsigned long height);

    // Support for buffer creation and deletion

    virtual unsigned createBuffer();

    virtual unsigned createFramebuffer();

    virtual unsigned createProgram();

    virtual unsigned createRenderbuffer();

    virtual unsigned createShader(unsigned long);

    virtual unsigned createTexture();

    virtual void deleteBuffer(unsigned);

    virtual void deleteFramebuffer(unsigned);

    virtual void deleteProgram(unsigned);

    virtual void deleteRenderbuffer(unsigned);

    virtual void deleteShader(unsigned);

    virtual void deleteTexture(unsigned);

private:

    WebGraphicsContext3D::Attributes m_attributes;

    bool m_initialized;

    unsigned int m_texture;

    unsigned int m_fbo;

    unsigned int m_depthStencilBuffer;

    unsigned int m_cachedWidth, m_cachedHeight;

    // For multisampling

    unsigned int m_multisampleFBO;

    unsigned int m_multisampleDepthStencilBuffer;

    unsigned int m_multisampleColorBuffer;

    // For tracking which FBO is bound

    unsigned int m_boundFBO;

#ifdef FLIP_FRAMEBUFFER_VERTICALLY

    unsigned char* m_scanline;

    void flipVertically(unsigned char* framebuffer,

                        unsigned int width,

                        unsigned int height);

#endif

    // Take into account the user's requested context creation attributes, in

    // particular stencil and antialias, and determine which could or could

    // not be honored based on the capabilities of the OpenGL implementation.

    void validateAttributes();

    // Note: we aren't currently using this information, but we will

    // need to in order to verify that all enabled vertex arrays have

    // a valid buffer bound -- to avoid crashes on certain cards.

    unsigned int m_boundArrayBuffer;

    class VertexAttribPointerState {

    public:

        VertexAttribPointerState();

        bool enabled;

        unsigned long buffer;

        unsigned long indx;

        int size;

        int type;

        bool normalized;

        unsigned long stride;

        unsigned long offset;

    };

    enum {

        NumTrackedPointerStates = 2

    };

    VertexAttribPointerState m_vertexAttribPointerState[NumTrackedPointerStates];

    // Errors raised by synthesizeGLError().

    ListHashSet<unsigned long> m_syntheticErrors;

    static bool s_initializedGLEW;

#if OS(WINDOWS)

    HWND  m_canvasWindow;

    HDC   m_canvasDC;

    HGLRC m_contextObj;

#elif PLATFORM(CG)

    CGLPBufferObj m_pbuffer;

    CGLContextObj m_contextObj;

    unsigned char* m_renderOutput;

#elif OS(LINUX)

    GLXContext m_contextObj;

    GLXPbuffer m_pbuffer;

    // In order to avoid problems caused by linking against libGL, we

    // dynamically look up all the symbols we need.

    // http://code.google.com/p/chromium/issues/detail?id=16800

    class GLConnection {

      public:

        ~GLConnection();

        static GLConnection* create();

        GLXFBConfig* chooseFBConfig(int screen, const int *attrib_list, int *nelements)

        {

            return m_glXChooseFBConfig(m_display, screen, attrib_list, nelements);

        }

        GLXContext createNewContext(GLXFBConfig config, int renderType, GLXContext shareList, Bool direct)

        {

            return m_glXCreateNewContext(m_display, config, renderType, shareList, direct);

        }

        GLXPbuffer createPbuffer(GLXFBConfig config, const int *attribList)

        {

            return m_glXCreatePbuffer(m_display, config, attribList);

        }

        void destroyPbuffer(GLXPbuffer pbuf)

        {

            m_glXDestroyPbuffer(m_display, pbuf);

        }

        Bool makeCurrent(GLXDrawable drawable, GLXContext ctx)

        {

            return m_glXMakeCurrent(m_display, drawable, ctx);

        }

        void destroyContext(GLXContext ctx)

        {

            m_glXDestroyContext(m_display, ctx);

        }

        GLXContext getCurrentContext()

        {

            return m_glXGetCurrentContext();

        }

      private:

        Display* m_display;

        void* m_libGL;

        PFNGLXCHOOSEFBCONFIGPROC m_glXChooseFBConfig;

        PFNGLXCREATENEWCONTEXTPROC m_glXCreateNewContext;

        PFNGLXCREATEPBUFFERPROC m_glXCreatePbuffer;

        PFNGLXDESTROYPBUFFERPROC m_glXDestroyPbuffer;

        typedef Bool (* PFNGLXMAKECURRENTPROC)(Display* dpy, GLXDrawable drawable, GLXContext ctx);

        PFNGLXMAKECURRENTPROC m_glXMakeCurrent;

        typedef void (* PFNGLXDESTROYCONTEXTPROC)(Display* dpy, GLXContext ctx);

        PFNGLXDESTROYCONTEXTPROC m_glXDestroyContext;

        typedef GLXContext (* PFNGLXGETCURRENTCONTEXTPROC)(void);

        PFNGLXGETCURRENTCONTEXTPROC m_glXGetCurrentContext;

        GLConnection(Display* display,

                     void* libGL,

                     PFNGLXCHOOSEFBCONFIGPROC chooseFBConfig,

                     PFNGLXCREATENEWCONTEXTPROC createNewContext,

                     PFNGLXCREATEPBUFFERPROC createPbuffer,

                     PFNGLXDESTROYPBUFFERPROC destroyPbuffer,

                     PFNGLXMAKECURRENTPROC makeCurrent,

                     PFNGLXDESTROYCONTEXTPROC destroyContext,

                     PFNGLXGETCURRENTCONTEXTPROC getCurrentContext)

            : m_libGL(libGL)

            , m_display(display)

            , m_glXChooseFBConfig(chooseFBConfig)

            , m_glXCreateNewContext(createNewContext)

            , m_glXCreatePbuffer(createPbuffer)

            , m_glXDestroyPbuffer(destroyPbuffer)

            , m_glXMakeCurrent(makeCurrent)

            , m_glXDestroyContext(destroyContext)

            , m_glXGetCurrentContext(getCurrentContext)

        {

        }

    };

    static GLConnection* s_gl;

#else

    #error Must port WebGraphicsContext3DDefaultImpl to your platform

#endif

};

} // namespace WebKit

#endif // ENABLE(3D_CANVAS)

#endif