/*
 * Copyright (C) 2013 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.telegram.android.video;

import android.annotation.TargetApi;
import android.opengl.EGL14;
import android.opengl.EGLExt;
import android.opengl.EGLConfig;
import android.opengl.EGLContext;
import android.opengl.EGLDisplay;
import android.opengl.EGLSurface;
import android.view.Surface;

@TargetApi(17)
public class InputSurface {
    private static final boolean VERBOSE = false;
    private static final int EGL_RECORDABLE_ANDROID = 0x3142;
    private static final int EGL_OPENGL_ES2_BIT = 4;
    private EGLDisplay mEGLDisplay;
    private EGLContext mEGLContext;
    private EGLSurface mEGLSurface;
    private Surface mSurface;

    public InputSurface(Surface surface) {
        if (surface == null) {
            throw new NullPointerException();
        }
        mSurface = surface;
        eglSetup();
    }

    private void eglSetup() {
        mEGLDisplay = EGL14.eglGetDisplay(EGL14.EGL_DEFAULT_DISPLAY);
        if (mEGLDisplay == EGL14.EGL_NO_DISPLAY) {
            throw new RuntimeException("unable to get EGL14 display");
        }
        int[] version = new int[2];
        if (!EGL14.eglInitialize(mEGLDisplay, version, 0, version, 1)) {
            mEGLDisplay = null;
            throw new RuntimeException("unable to initialize EGL14");
        }

        int[] attribList = {
                EGL14.EGL_RED_SIZE, 8,
                EGL14.EGL_GREEN_SIZE, 8,
                EGL14.EGL_BLUE_SIZE, 8,
                EGL14.EGL_RENDERABLE_TYPE, EGL_OPENGL_ES2_BIT,
                EGL_RECORDABLE_ANDROID, 1,
                EGL14.EGL_NONE
        };
        EGLConfig[] configs = new EGLConfig[1];
        int[] numConfigs = new int[1];
        if (!EGL14.eglChooseConfig(mEGLDisplay, attribList, 0, configs, 0, configs.length,
                numConfigs, 0)) {
            throw new RuntimeException("unable to find RGB888+recordable ES2 EGL config");
        }

        int[] attrib_list = {
                EGL14.EGL_CONTEXT_CLIENT_VERSION, 2,
                EGL14.EGL_NONE
        };

        mEGLContext = EGL14.eglCreateContext(mEGLDisplay, configs[0], EGL14.EGL_NO_CONTEXT, attrib_list, 0);
        checkEglError("eglCreateContext");
        if (mEGLContext == null) {
            throw new RuntimeException("null context");
        }

        int[] surfaceAttribs = {
                EGL14.EGL_NONE
        };
        mEGLSurface = EGL14.eglCreateWindowSurface(mEGLDisplay, configs[0], mSurface,
                surfaceAttribs, 0);
        checkEglError("eglCreateWindowSurface");
        if (mEGLSurface == null) {
            throw new RuntimeException("surface was null");
        }
    }

    public void release() {
        if (EGL14.eglGetCurrentContext().equals(mEGLContext)) {
            EGL14.eglMakeCurrent(mEGLDisplay, EGL14.EGL_NO_SURFACE, EGL14.EGL_NO_SURFACE, EGL14.EGL_NO_CONTEXT);
        }
        EGL14.eglDestroySurface(mEGLDisplay, mEGLSurface);
        EGL14.eglDestroyContext(mEGLDisplay, mEGLContext);
        mSurface.release();
        mEGLDisplay = null;
        mEGLContext = null;
        mEGLSurface = null;
        mSurface = null;
    }

    public void makeCurrent() {
        if (!EGL14.eglMakeCurrent(mEGLDisplay, mEGLSurface, mEGLSurface, mEGLContext)) {
            throw new RuntimeException("eglMakeCurrent failed");
        }
    }

    public boolean swapBuffers() {
        return EGL14.eglSwapBuffers(mEGLDisplay, mEGLSurface);
    }

    public Surface getSurface() {
        return mSurface;
    }

    public void setPresentationTime(long nsecs) {
        EGLExt.eglPresentationTimeANDROID(mEGLDisplay, mEGLSurface, nsecs);
    }

    private void checkEglError(String msg) {
        boolean failed = false;
        int error;
        while ((error = EGL14.eglGetError()) != EGL14.EGL_SUCCESS) {
            failed = true;
        }
        if (failed) {
            throw new RuntimeException("EGL error encountered (see log)");
        }
    }
}
