/*
 * Copyright (c) 2008 Sun Microsystems, Inc. All Rights Reserved.
 * Copyright (c) 2011 JogAmp Community. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 * - Redistribution of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 *
 * - Redistribution 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 Sun Microsystems, Inc. or the names of
 * contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.
 *
 * This software is provided "AS IS," without a warranty of any kind. ALL
 * EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND WARRANTIES,
 * INCLUDING ANY IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS FOR A
 * PARTICULAR PURPOSE OR NON-INFRINGEMENT, ARE HEREBY EXCLUDED. SUN
 * MICROSYSTEMS, INC. ("SUN") AND ITS LICENSORS SHALL NOT BE LIABLE FOR
 * ANY DAMAGES SUFFERED BY LICENSEE AS A RESULT OF USING, MODIFYING OR
 * DISTRIBUTING THIS SOFTWARE OR ITS DERIVATIVES. IN NO EVENT WILL SUN OR
 * ITS LICENSORS BE LIABLE FOR ANY LOST REVENUE, PROFIT OR DATA, OR FOR
 * DIRECT, INDIRECT, SPECIAL, CONSEQUENTIAL, INCIDENTAL OR PUNITIVE
 * DAMAGES, HOWEVER CAUSED AND REGARDLESS OF THE THEORY OF LIABILITY,
 * ARISING OUT OF THE USE OF OR INABILITY TO USE THIS SOFTWARE, EVEN IF
 * SUN HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
 *
 * Sun gratefully acknowledges that this software was originally authored
 * and developed by Kenneth Bradley Russell and Christopher John Kline.
 */

package jogamp.opengl.egl;

import java.nio.ByteBuffer;
import java.nio.IntBuffer;
import java.util.Map;

import javax.media.nativewindow.AbstractGraphicsConfiguration;
import javax.media.nativewindow.AbstractGraphicsDevice;
import javax.media.opengl.GLCapabilitiesImmutable;
import javax.media.opengl.GLContext;
import javax.media.opengl.GLDrawableFactory;
import javax.media.opengl.GLException;
import javax.media.opengl.GLProfile;

import jogamp.opengl.GLContextImpl;
import jogamp.opengl.GLDrawableImpl;

import com.jogamp.common.nio.Buffers;
import com.jogamp.gluegen.runtime.ProcAddressTable;
import com.jogamp.gluegen.runtime.opengl.GLProcAddressResolver;
import com.jogamp.nativewindow.egl.EGLGraphicsDevice;
import com.jogamp.opengl.GLRendererQuirks;

public class EGLContext extends GLContextImpl {
    private boolean eglQueryStringInitialized;
    private boolean eglQueryStringAvailable;
    private EGLExt _eglExt;
    // Table that holds the addresses of the native C-language entry points for
    // EGL extension functions.
    private EGLExtProcAddressTable eglExtProcAddressTable;

    EGLContext(final GLDrawableImpl drawable,
               final GLContext shareWith) {
        super(drawable, shareWith);
    }

    @Override
    protected void resetStates(final boolean isInit) {
        eglQueryStringInitialized = false;
        eglQueryStringAvailable = false;
        eglExtProcAddressTable = null;
        // no inner state _eglExt = null;
        super.resetStates(isInit);
    }

    @Override
    public Object getPlatformGLExtensions() {
      return getEGLExt();
    }

    public EGLExt getEGLExt() {
      if (_eglExt == null) {
        _eglExt = new EGLExtImpl(this);
      }
      return _eglExt;
    }

    @Override
    public final ProcAddressTable getPlatformExtProcAddressTable() {
        return eglExtProcAddressTable;
    }

    public final EGLExtProcAddressTable getEGLExtProcAddressTable() {
        return eglExtProcAddressTable;
    }

    @Override
    protected Map<String, String> getFunctionNameMap() { return null; }

    @Override
    protected Map<String, String> getExtensionNameMap() { return null; }

    @Override
    public final boolean isGLReadDrawableAvailable() {
        return true;
    }

    @Override
    protected void makeCurrentImpl() throws GLException {
        if (EGL.eglGetCurrentContext() != contextHandle) {
            final long dpy = drawable.getNativeSurface().getDisplayHandle();
            if (!EGL.eglMakeCurrent(dpy, drawable.getHandle(), drawableRead.getHandle(), contextHandle)) {
                throw new GLException("Error making context " + toHexString(contextHandle) +
                                      " current on Thread " + getThreadName() +
                                      " with display " + toHexString(dpy) +
                                      ", drawableWrite " + toHexString(drawable.getHandle()) +
                                      ", drawableRead "+ toHexString(drawableRead.getHandle()) +
                                      " - Error code " + toHexString(EGL.eglGetError()) + ", " + this);
            }
        }
    }

    @Override
    protected void releaseImpl() throws GLException {
      if (!EGL.eglMakeCurrent(drawable.getNativeSurface().getDisplayHandle(), EGL.EGL_NO_SURFACE, EGL.EGL_NO_SURFACE, EGL.EGL_NO_CONTEXT)) {
            throw new GLException("Error freeing OpenGL context " + toHexString(contextHandle) +
                                  ": error code " + toHexString(EGL.eglGetError()));
      }
    }

    @Override
    protected void destroyImpl() throws GLException {
        destroyContextARBImpl(contextHandle);
    }

    @Override
    protected long createContextARBImpl(final long share, final boolean direct, final int ctp, final int major, final int minor) {
        return 0; // FIXME
    }

    @Override
    protected void destroyContextARBImpl(final long _context) {
        if (!EGL.eglDestroyContext(drawable.getNativeSurface().getDisplayHandle(), _context)) {
            final int eglError = EGL.eglGetError();
            if(EGL.EGL_SUCCESS != eglError) { /* oops, Mesa EGL impl. may return false, but has no EGL error */
                throw new GLException("Error destroying OpenGL context " + toHexString(_context) +
                        ": error code " + toHexString(eglError));
            }
        }
    }

    @Override
    protected boolean createImpl(final long shareWithHandle) throws GLException {
        final EGLGraphicsConfiguration config = (EGLGraphicsConfiguration) drawable.getNativeSurface().getGraphicsConfiguration();
        final long eglDisplay = config.getScreen().getDevice().getHandle();
        final GLProfile glProfile = drawable.getGLProfile();
        final long eglConfig = config.getNativeConfig();
        // 0 == EGL.EGL_NO_CONTEXT;

        if ( 0 == eglDisplay ) {
            throw new GLException("Error: attempted to create an OpenGL context without a display connection");
        }
        if ( 0 == eglConfig ) {
            throw new GLException("Error: attempted to create an OpenGL context without a graphics configuration");
        }

        try {
            // might be unavailable on EGL < 1.2
            if( !EGL.eglBindAPI(EGL.EGL_OPENGL_ES_API) ) {
                throw new GLException("Caught: eglBindAPI to ES failed , error "+toHexString(EGL.eglGetError()));
            }
        } catch (final GLException glex) {
            if (DEBUG) {
                glex.printStackTrace();
            }
        }

        // Cannot check extension 'EGL_KHR_create_context' before having one current!

        final IntBuffer contextAttrsNIO;
        final int contextVersionReq, contextVersionAttr;
        {
            if ( glProfile.usesNativeGLES3() ) {
                contextVersionReq = 3;
                if( GLRendererQuirks.existStickyDeviceQuirk( GLDrawableFactory.getEGLFactory().getDefaultDevice(), GLRendererQuirks.GLES3ViaEGLES2Config) ) {
                    contextVersionAttr = 2;
                } else {
                    contextVersionAttr = 3;
                }
            } else if ( glProfile.usesNativeGLES2() ) {
                contextVersionReq = 2;
                contextVersionAttr = 2;
            } else if ( glProfile.usesNativeGLES1() ) {
                contextVersionReq = 1;
                contextVersionAttr = 1;
            } else {
                throw new GLException("Error creating OpenGL context - invalid GLProfile: "+glProfile);
            }
            // EGLExt.EGL_CONTEXT_MAJOR_VERSION_KHR == EGL.EGL_CONTEXT_CLIENT_VERSION
            final int[] contextAttrs = new int[] { EGL.EGL_CONTEXT_CLIENT_VERSION, contextVersionAttr, EGL.EGL_NONE };
            contextAttrsNIO = Buffers.newDirectIntBuffer(contextAttrs);
        }
        contextHandle = EGL.eglCreateContext(eglDisplay, eglConfig, shareWithHandle, contextAttrsNIO);
        if (contextHandle == 0) {
            throw new GLException("Error creating OpenGL context: eglDisplay "+toHexString(eglDisplay)+
                                  ", eglConfig "+config+", "+glProfile+", shareWith "+toHexString(shareWithHandle)+", error "+toHexString(EGL.eglGetError()));
        }
        if (DEBUG) {
            System.err.println(getThreadName() + ": Created OpenGL context 0x" +
                               Long.toHexString(contextHandle) +
                               ",\n\twrite surface 0x" + Long.toHexString(drawable.getHandle()) +
                               ",\n\tread  surface 0x" + Long.toHexString(drawableRead.getHandle())+
                               ",\n\t"+this+
                               ",\n\tsharing with 0x" + Long.toHexString(shareWithHandle));
        }
        if (!EGL.eglMakeCurrent(eglDisplay, drawable.getHandle(), drawableRead.getHandle(), contextHandle)) {
            throw new GLException("Error making context " +
                                  toHexString(contextHandle) + " current: error code " + toHexString(EGL.eglGetError()));
        }
        if( !setGLFunctionAvailability(true, contextVersionReq, 0, CTX_PROFILE_ES,
                                       true /* strictMatch */, // always req. strict match
                                       false /* withinGLVersionsMapping */) ) {
            if(DEBUG) {
                System.err.println(getThreadName() + ": createImpl: setGLFunctionAvailability FAILED delete "+toHexString(contextHandle));
            }
            EGL.eglMakeCurrent(drawable.getNativeSurface().getDisplayHandle(), EGL.EGL_NO_SURFACE, EGL.EGL_NO_SURFACE, EGL.EGL_NO_CONTEXT);
            EGL.eglDestroyContext(drawable.getNativeSurface().getDisplayHandle(), contextHandle);
            contextHandle = 0;
            return false;
        } else {
            return true;
        }
    }

    @Override
    protected final void updateGLXProcAddressTable() {
        final AbstractGraphicsConfiguration aconfig = drawable.getNativeSurface().getGraphicsConfiguration();
        final AbstractGraphicsDevice adevice = aconfig.getScreen().getDevice();
        final String key = "EGL-"+adevice.getUniqueID();
        if (DEBUG) {
          System.err.println(getThreadName() + ": Initializing EGLextension address table: "+key);
        }
        eglQueryStringInitialized = false;
        eglQueryStringAvailable = false;

        ProcAddressTable table = null;
        synchronized(mappedContextTypeObjectLock) {
            table = mappedGLXProcAddress.get( key );
        }
        if(null != table) {
            eglExtProcAddressTable = (EGLExtProcAddressTable) table;
            if(DEBUG) {
                System.err.println(getThreadName() + ": GLContext EGL ProcAddressTable reusing key("+key+") -> "+toHexString(table.hashCode()));
            }
        } else {
            eglExtProcAddressTable = new EGLExtProcAddressTable(new GLProcAddressResolver());
            resetProcAddressTable(getEGLExtProcAddressTable());
            synchronized(mappedContextTypeObjectLock) {
                mappedGLXProcAddress.put(key, getEGLExtProcAddressTable());
                if(DEBUG) {
                    System.err.println(getThreadName() + ": GLContext EGL ProcAddressTable mapping key("+key+") -> "+toHexString(getEGLExtProcAddressTable().hashCode()));
                }
            }
        }
    }

    @Override
    protected final StringBuilder getPlatformExtensionsStringImpl() {
        final StringBuilder sb = new StringBuilder();
        if (!eglQueryStringInitialized) {
          eglQueryStringAvailable = getDrawableImpl().getGLDynamicLookupHelper().isFunctionAvailable("eglQueryString");
          eglQueryStringInitialized = true;
        }
        if (eglQueryStringAvailable) {
            final String ret = EGL.eglQueryString(drawable.getNativeSurface().getDisplayHandle(), EGL.EGL_EXTENSIONS);
            if (DEBUG) {
              System.err.println("EGL extensions: " + ret);
            }
            sb.append(ret);
        }
        return sb;
    }

    @Override
    protected boolean setSwapIntervalImpl(final int interval) {
        if( hasRendererQuirk(GLRendererQuirks.NoSetSwapInterval) ) {
            return false;
        }
        return EGL.eglSwapInterval(drawable.getNativeSurface().getDisplayHandle(), interval);
    }

    //
    // Accessible ..
    //

    /* pp */ void mapCurrentAvailableGLVersion(final AbstractGraphicsDevice device) {
        mapStaticGLVersion(device, ctxVersion.getMajor(), ctxVersion.getMinor(), ctxOptions);
    }
    /* pp */ int getContextOptions() { return ctxOptions; }
    /* pp */ static void mapStaticGLESVersion(final AbstractGraphicsDevice device, final GLCapabilitiesImmutable caps) {
        final GLProfile glp = caps.getGLProfile();
        final int[] reqMajorCTP = new int[2];
        GLContext.getRequestMajorAndCompat(glp, reqMajorCTP);
        if( glp.isGLES() ) {
            if( reqMajorCTP[0] >= 3 ) {
                reqMajorCTP[1] |= GLContext.CTX_IMPL_ES3_COMPAT | GLContext.CTX_IMPL_ES2_COMPAT | GLContext.CTX_IMPL_FBO ;
            } else if( reqMajorCTP[0] >= 2 ) {
                reqMajorCTP[1] |= GLContext.CTX_IMPL_ES2_COMPAT | GLContext.CTX_IMPL_FBO ;
            }
        }
        if( !caps.getHardwareAccelerated() ) {
            reqMajorCTP[1] |= GLContext.CTX_IMPL_ACCEL_SOFT;
        }
        mapStaticGLVersion(device, reqMajorCTP[0], 0, reqMajorCTP[1]);
    }
    /* pp */ static void mapStaticGLVersion(final AbstractGraphicsDevice device, final int major, final int minor, final int ctp) {
        if( 0 != ( ctp & GLContext.CTX_PROFILE_ES) ) {
            // ES1, ES2, ES3, ..
            mapStaticGLVersion(device, major /* reqMajor */, major, minor, ctp);
            if( 3 == major ) {
                // map ES2 -> ES3
                mapStaticGLVersion(device, 2 /* reqMajor */, major, minor, ctp);
            }
        }
    }
    private static void mapStaticGLVersion(final AbstractGraphicsDevice device, final int reqMajor, final int major, final int minor, final int ctp) {
        GLContext.mapAvailableGLVersion(device, reqMajor, GLContext.CTX_PROFILE_ES, major, minor, ctp);
        if(! ( device instanceof EGLGraphicsDevice ) ) {
            final EGLGraphicsDevice eglDevice = new EGLGraphicsDevice(device.getHandle(), EGL.EGL_NO_DISPLAY, device.getConnection(), device.getUnitID(), null);
            GLContext.mapAvailableGLVersion(eglDevice, reqMajor, GLContext.CTX_PROFILE_ES, major, minor, ctp);
        }
    }
    protected static String getGLVersion(final int major, final int minor, final int ctp, final String gl_version) {
        return GLContext.getGLVersion(major, minor, ctp, gl_version);
    }

    protected static boolean getAvailableGLVersionsSet(final AbstractGraphicsDevice device) {
        return GLContext.getAvailableGLVersionsSet(device);
    }
    protected static void setAvailableGLVersionsSet(final AbstractGraphicsDevice device) {
        GLContext.setAvailableGLVersionsSet(device);
    }

    protected static String toHexString(final int hex) {
        return GLContext.toHexString(hex);
    }
    protected static String toHexString(final long hex) {
        return GLContext.toHexString(hex);
    }

    //----------------------------------------------------------------------
    // Currently unimplemented stuff
    //

    @Override
    protected void copyImpl(final GLContext source, final int mask) throws GLException {
        throw new GLException("Not yet implemented");
    }

    @Override
    public final ByteBuffer glAllocateMemoryNV(final int size, final float readFrequency, final float writeFrequency, final float priority) {
        throw new GLException("Should not call this");
    }

    @Override
    public final void glFreeMemoryNV(final ByteBuffer pointer) {
        throw new GLException("Should not call this");
    }
}