/*
 * Copyright (C) 2011 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.
 */

#include <ui/FramebufferNativeWindow.h>
#include <ui/PixelFormat.h>

#include <system/window.h>

#include <sys/types.h>
#include <sys/resource.h>
#include <sched.h>

#include <cutils/properties.h>

#include <GLES/gl.h>
#include <GLES/glext.h>
#include <GLES2/gl2.h>
#include <GLES2/gl2ext.h>

#include <string.h>

#include "rsdCore.h"
#include "rsdGL.h"

#include <malloc.h>
#include "rsContext.h"
#include "rsdShaderCache.h"
#include "rsdVertexArray.h"
#include "rsdFrameBufferObj.h"

using namespace android;
using namespace android::renderscript;

static int32_t gGLContextCount = 0;

static void checkEglError(const char* op, EGLBoolean returnVal = EGL_TRUE) {
    struct EGLUtils {
        static const char *strerror(EGLint err) {
            switch (err){
                case EGL_SUCCESS:           return "EGL_SUCCESS";
                case EGL_NOT_INITIALIZED:   return "EGL_NOT_INITIALIZED";
                case EGL_BAD_ACCESS:        return "EGL_BAD_ACCESS";
                case EGL_BAD_ALLOC:         return "EGL_BAD_ALLOC";
                case EGL_BAD_ATTRIBUTE:     return "EGL_BAD_ATTRIBUTE";
                case EGL_BAD_CONFIG:        return "EGL_BAD_CONFIG";
                case EGL_BAD_CONTEXT:       return "EGL_BAD_CONTEXT";
                case EGL_BAD_CURRENT_SURFACE: return "EGL_BAD_CURRENT_SURFACE";
                case EGL_BAD_DISPLAY:       return "EGL_BAD_DISPLAY";
                case EGL_BAD_MATCH:         return "EGL_BAD_MATCH";
                case EGL_BAD_NATIVE_PIXMAP: return "EGL_BAD_NATIVE_PIXMAP";
                case EGL_BAD_NATIVE_WINDOW: return "EGL_BAD_NATIVE_WINDOW";
                case EGL_BAD_PARAMETER:     return "EGL_BAD_PARAMETER";
                case EGL_BAD_SURFACE:       return "EGL_BAD_SURFACE";
                case EGL_CONTEXT_LOST:      return "EGL_CONTEXT_LOST";
                default: return "UNKNOWN";
            }
        }
    };

    if (returnVal != EGL_TRUE) {
        fprintf(stderr, "%s() returned %d\n", op, returnVal);
    }

    for (EGLint error = eglGetError(); error != EGL_SUCCESS; error
            = eglGetError()) {
        fprintf(stderr, "after %s() eglError %s (0x%x)\n", op, EGLUtils::strerror(error),
                error);
    }
}

static void printEGLConfiguration(EGLDisplay dpy, EGLConfig config) {

#define X(VAL) {VAL, #VAL}
    struct {EGLint attribute; const char* name;} names[] = {
    X(EGL_BUFFER_SIZE),
    X(EGL_ALPHA_SIZE),
    X(EGL_BLUE_SIZE),
    X(EGL_GREEN_SIZE),
    X(EGL_RED_SIZE),
    X(EGL_DEPTH_SIZE),
    X(EGL_STENCIL_SIZE),
    X(EGL_CONFIG_CAVEAT),
    X(EGL_CONFIG_ID),
    X(EGL_LEVEL),
    X(EGL_MAX_PBUFFER_HEIGHT),
    X(EGL_MAX_PBUFFER_PIXELS),
    X(EGL_MAX_PBUFFER_WIDTH),
    X(EGL_NATIVE_RENDERABLE),
    X(EGL_NATIVE_VISUAL_ID),
    X(EGL_NATIVE_VISUAL_TYPE),
    X(EGL_SAMPLES),
    X(EGL_SAMPLE_BUFFERS),
    X(EGL_SURFACE_TYPE),
    X(EGL_TRANSPARENT_TYPE),
    X(EGL_TRANSPARENT_RED_VALUE),
    X(EGL_TRANSPARENT_GREEN_VALUE),
    X(EGL_TRANSPARENT_BLUE_VALUE),
    X(EGL_BIND_TO_TEXTURE_RGB),
    X(EGL_BIND_TO_TEXTURE_RGBA),
    X(EGL_MIN_SWAP_INTERVAL),
    X(EGL_MAX_SWAP_INTERVAL),
    X(EGL_LUMINANCE_SIZE),
    X(EGL_ALPHA_MASK_SIZE),
    X(EGL_COLOR_BUFFER_TYPE),
    X(EGL_RENDERABLE_TYPE),
    X(EGL_CONFORMANT),
   };
#undef X

    for (size_t j = 0; j < sizeof(names) / sizeof(names[0]); j++) {
        EGLint value = -1;
        EGLBoolean returnVal = eglGetConfigAttrib(dpy, config, names[j].attribute, &value);
        if (returnVal) {
            ALOGV(" %s: %d (0x%x)", names[j].name, value, value);
        }
    }
}

static void DumpDebug(RsdHal *dc) {
    ALOGE(" EGL ver %i %i", dc->gl.egl.majorVersion, dc->gl.egl.minorVersion);
    ALOGE(" EGL context %p  surface %p,  Display=%p", dc->gl.egl.context, dc->gl.egl.surface,
         dc->gl.egl.display);
    ALOGE(" GL vendor: %s", dc->gl.gl.vendor);
    ALOGE(" GL renderer: %s", dc->gl.gl.renderer);
    ALOGE(" GL Version: %s", dc->gl.gl.version);
    ALOGE(" GL Extensions: %s", dc->gl.gl.extensions);
    ALOGE(" GL int Versions %i %i", dc->gl.gl.majorVersion, dc->gl.gl.minorVersion);

    ALOGV("MAX Textures %i, %i  %i", dc->gl.gl.maxVertexTextureUnits,
         dc->gl.gl.maxFragmentTextureImageUnits, dc->gl.gl.maxTextureImageUnits);
    ALOGV("MAX Attribs %i", dc->gl.gl.maxVertexAttribs);
    ALOGV("MAX Uniforms %i, %i", dc->gl.gl.maxVertexUniformVectors,
         dc->gl.gl.maxFragmentUniformVectors);
    ALOGV("MAX Varyings %i", dc->gl.gl.maxVaryingVectors);
}

void rsdGLShutdown(const Context *rsc) {
    RsdHal *dc = (RsdHal *)rsc->mHal.drv;

    dc->gl.shaderCache->cleanupAll();
    delete dc->gl.shaderCache;
    delete dc->gl.vertexArrayState;

    if (dc->gl.egl.context != EGL_NO_CONTEXT) {
        RSD_CALL_GL(eglMakeCurrent, dc->gl.egl.display,
                    EGL_NO_SURFACE, EGL_NO_SURFACE, EGL_NO_CONTEXT);
        RSD_CALL_GL(eglDestroySurface, dc->gl.egl.display, dc->gl.egl.surfaceDefault);
        if (dc->gl.egl.surface != EGL_NO_SURFACE) {
            RSD_CALL_GL(eglDestroySurface, dc->gl.egl.display, dc->gl.egl.surface);
        }
        RSD_CALL_GL(eglDestroyContext, dc->gl.egl.display, dc->gl.egl.context);
        checkEglError("eglDestroyContext");
    }

    gGLContextCount--;
    if (!gGLContextCount) {
        RSD_CALL_GL(eglTerminate, dc->gl.egl.display);
    }
}

bool rsdGLInit(const Context *rsc) {
    RsdHal *dc = (RsdHal *)rsc->mHal.drv;

    dc->gl.egl.numConfigs = -1;
    EGLint configAttribs[128];
    EGLint *configAttribsPtr = configAttribs;
    EGLint context_attribs2[] = { EGL_CONTEXT_CLIENT_VERSION, 2, EGL_NONE };

    memset(configAttribs, 0, sizeof(configAttribs));

    configAttribsPtr[0] = EGL_SURFACE_TYPE;
    configAttribsPtr[1] = EGL_WINDOW_BIT;
    configAttribsPtr += 2;

    configAttribsPtr[0] = EGL_RENDERABLE_TYPE;
    configAttribsPtr[1] = EGL_OPENGL_ES2_BIT;
    configAttribsPtr += 2;

    configAttribsPtr[0] = EGL_RED_SIZE;
    configAttribsPtr[1] = 8;
    configAttribsPtr += 2;

    configAttribsPtr[0] = EGL_GREEN_SIZE;
    configAttribsPtr[1] = 8;
    configAttribsPtr += 2;

    configAttribsPtr[0] = EGL_BLUE_SIZE;
    configAttribsPtr[1] = 8;
    configAttribsPtr += 2;

    if (rsc->mUserSurfaceConfig.alphaMin > 0) {
        configAttribsPtr[0] = EGL_ALPHA_SIZE;
        configAttribsPtr[1] = rsc->mUserSurfaceConfig.alphaMin;
        configAttribsPtr += 2;
    }

    if (rsc->mUserSurfaceConfig.depthMin > 0) {
        configAttribsPtr[0] = EGL_DEPTH_SIZE;
        configAttribsPtr[1] = rsc->mUserSurfaceConfig.depthMin;
        configAttribsPtr += 2;
    }

    if (rsc->mDev->mForceSW) {
        configAttribsPtr[0] = EGL_CONFIG_CAVEAT;
        configAttribsPtr[1] = EGL_SLOW_CONFIG;
        configAttribsPtr += 2;
    }

    configAttribsPtr[0] = EGL_NONE;
    rsAssert(configAttribsPtr < (configAttribs + (sizeof(configAttribs) / sizeof(EGLint))));

    ALOGV("%p initEGL start", rsc);
    rsc->setWatchdogGL("eglGetDisplay", __LINE__, __FILE__);
    dc->gl.egl.display = eglGetDisplay(EGL_DEFAULT_DISPLAY);
    checkEglError("eglGetDisplay");

    RSD_CALL_GL(eglInitialize, dc->gl.egl.display,
                &dc->gl.egl.majorVersion, &dc->gl.egl.minorVersion);
    checkEglError("eglInitialize");

    EGLBoolean ret;

    EGLint numConfigs = -1, n = 0;
    rsc->setWatchdogGL("eglChooseConfig", __LINE__, __FILE__);
    ret = eglChooseConfig(dc->gl.egl.display, configAttribs, 0, 0, &numConfigs);
    checkEglError("eglGetConfigs", ret);

    eglSwapInterval(dc->gl.egl.display, 0);

    if (numConfigs) {
        EGLConfig* const configs = new EGLConfig[numConfigs];

        rsc->setWatchdogGL("eglChooseConfig", __LINE__, __FILE__);
        ret = eglChooseConfig(dc->gl.egl.display,
                configAttribs, configs, numConfigs, &n);
        if (!ret || !n) {
            checkEglError("eglChooseConfig", ret);
            ALOGE("%p, couldn't find an EGLConfig matching the screen format\n", rsc);
        }

        // The first config is guaranteed to over-satisfy the constraints
        dc->gl.egl.config = configs[0];

        // go through the list and skip configs that over-satisfy our needs
        for (int i=0 ; i<n ; i++) {
            if (rsc->mUserSurfaceConfig.alphaMin <= 0) {
                EGLint alphaSize;
                eglGetConfigAttrib(dc->gl.egl.display,
                        configs[i], EGL_ALPHA_SIZE, &alphaSize);
                if (alphaSize > 0) {
                    continue;
                }
            }

            if (rsc->mUserSurfaceConfig.depthMin <= 0) {
                EGLint depthSize;
                eglGetConfigAttrib(dc->gl.egl.display,
                        configs[i], EGL_DEPTH_SIZE, &depthSize);
                if (depthSize > 0) {
                    continue;
                }
            }

            // Found one!
            dc->gl.egl.config = configs[i];
            break;
        }

        delete [] configs;
    }

    //if (props.mLogVisual) {
    if (0) {
        printEGLConfiguration(dc->gl.egl.display, dc->gl.egl.config);
    }
    //}

    rsc->setWatchdogGL("eglCreateContext", __LINE__, __FILE__);
    dc->gl.egl.context = eglCreateContext(dc->gl.egl.display, dc->gl.egl.config,
                                          EGL_NO_CONTEXT, context_attribs2);
    checkEglError("eglCreateContext");
    if (dc->gl.egl.context == EGL_NO_CONTEXT) {
        ALOGE("%p, eglCreateContext returned EGL_NO_CONTEXT", rsc);
        rsc->setWatchdogGL(NULL, 0, NULL);
        return false;
    }
    gGLContextCount++;


    EGLint pbuffer_attribs[] = { EGL_WIDTH, 1, EGL_HEIGHT, 1, EGL_NONE };
    rsc->setWatchdogGL("eglCreatePbufferSurface", __LINE__, __FILE__);
    dc->gl.egl.surfaceDefault = eglCreatePbufferSurface(dc->gl.egl.display, dc->gl.egl.config,
                                                        pbuffer_attribs);
    checkEglError("eglCreatePbufferSurface");
    if (dc->gl.egl.surfaceDefault == EGL_NO_SURFACE) {
        ALOGE("eglCreatePbufferSurface returned EGL_NO_SURFACE");
        rsdGLShutdown(rsc);
        rsc->setWatchdogGL(NULL, 0, NULL);
        return false;
    }

    rsc->setWatchdogGL("eglMakeCurrent", __LINE__, __FILE__);
    ret = eglMakeCurrent(dc->gl.egl.display, dc->gl.egl.surfaceDefault,
                         dc->gl.egl.surfaceDefault, dc->gl.egl.context);
    if (ret == EGL_FALSE) {
        ALOGE("eglMakeCurrent returned EGL_FALSE");
        checkEglError("eglMakeCurrent", ret);
        rsdGLShutdown(rsc);
        rsc->setWatchdogGL(NULL, 0, NULL);
        return false;
    }

    dc->gl.gl.version = glGetString(GL_VERSION);
    dc->gl.gl.vendor = glGetString(GL_VENDOR);
    dc->gl.gl.renderer = glGetString(GL_RENDERER);
    dc->gl.gl.extensions = glGetString(GL_EXTENSIONS);

    //ALOGV("EGL Version %i %i", mEGL.mMajorVersion, mEGL.mMinorVersion);
    //ALOGV("GL Version %s", mGL.mVersion);
    //ALOGV("GL Vendor %s", mGL.mVendor);
    //ALOGV("GL Renderer %s", mGL.mRenderer);
    //ALOGV("GL Extensions %s", mGL.mExtensions);

    const char *verptr = NULL;
    if (strlen((const char *)dc->gl.gl.version) > 9) {
        if (!memcmp(dc->gl.gl.version, "OpenGL ES-CM", 12)) {
            verptr = (const char *)dc->gl.gl.version + 12;
        }
        if (!memcmp(dc->gl.gl.version, "OpenGL ES ", 10)) {
            verptr = (const char *)dc->gl.gl.version + 9;
        }
    }

    if (!verptr) {
        ALOGE("Error, OpenGL ES Lite not supported");
        rsdGLShutdown(rsc);
        rsc->setWatchdogGL(NULL, 0, NULL);
        return false;
    } else {
        sscanf(verptr, " %i.%i", &dc->gl.gl.majorVersion, &dc->gl.gl.minorVersion);
    }

    glGetIntegerv(GL_MAX_VERTEX_ATTRIBS, &dc->gl.gl.maxVertexAttribs);
    glGetIntegerv(GL_MAX_VERTEX_UNIFORM_VECTORS, &dc->gl.gl.maxVertexUniformVectors);
    glGetIntegerv(GL_MAX_VERTEX_TEXTURE_IMAGE_UNITS, &dc->gl.gl.maxVertexTextureUnits);

    glGetIntegerv(GL_MAX_VARYING_VECTORS, &dc->gl.gl.maxVaryingVectors);
    glGetIntegerv(GL_MAX_COMBINED_TEXTURE_IMAGE_UNITS, &dc->gl.gl.maxTextureImageUnits);

    glGetIntegerv(GL_MAX_TEXTURE_IMAGE_UNITS, &dc->gl.gl.maxFragmentTextureImageUnits);
    glGetIntegerv(GL_MAX_FRAGMENT_UNIFORM_VECTORS, &dc->gl.gl.maxFragmentUniformVectors);

    dc->gl.gl.OES_texture_npot = NULL != strstr((const char *)dc->gl.gl.extensions,
                                                "GL_OES_texture_npot");
    dc->gl.gl.IMG_texture_npot = NULL != strstr((const char *)dc->gl.gl.extensions,
                                                   "GL_IMG_texture_npot");
    dc->gl.gl.NV_texture_npot_2D_mipmap = NULL != strstr((const char *)dc->gl.gl.extensions,
                                                            "GL_NV_texture_npot_2D_mipmap");
    dc->gl.gl.EXT_texture_max_aniso = 1.0f;
    bool hasAniso = NULL != strstr((const char *)dc->gl.gl.extensions,
                                   "GL_EXT_texture_filter_anisotropic");
    if (hasAniso) {
        glGetFloatv(GL_MAX_TEXTURE_MAX_ANISOTROPY_EXT, &dc->gl.gl.EXT_texture_max_aniso);
    }

    if (0) {
        DumpDebug(dc);
    }

    dc->gl.shaderCache = new RsdShaderCache();
    dc->gl.vertexArrayState = new RsdVertexArrayState();
    dc->gl.vertexArrayState->init(dc->gl.gl.maxVertexAttribs);
    dc->gl.currentFrameBuffer = NULL;
    dc->mHasGraphics = true;

    ALOGV("%p initGLThread end", rsc);
    rsc->setWatchdogGL(NULL, 0, NULL);
    return true;
}


bool rsdGLSetSurface(const Context *rsc, uint32_t w, uint32_t h, RsNativeWindow sur) {
    RsdHal *dc = (RsdHal *)rsc->mHal.drv;

    EGLBoolean ret;
    // WAR: Some drivers fail to handle 0 size surfaces correcntly.
    // Use the pbuffer to avoid this pitfall.
    if ((dc->gl.egl.surface != NULL) || (w == 0) || (h == 0)) {
        rsc->setWatchdogGL("eglMakeCurrent", __LINE__, __FILE__);
        ret = eglMakeCurrent(dc->gl.egl.display, dc->gl.egl.surfaceDefault,
                             dc->gl.egl.surfaceDefault, dc->gl.egl.context);
        checkEglError("eglMakeCurrent", ret);

        rsc->setWatchdogGL("eglDestroySurface", __LINE__, __FILE__);
        ret = eglDestroySurface(dc->gl.egl.display, dc->gl.egl.surface);
        checkEglError("eglDestroySurface", ret);

        dc->gl.egl.surface = NULL;
        dc->gl.width = 1;
        dc->gl.height = 1;
    }

    if (dc->gl.wndSurface != NULL) {
        dc->gl.wndSurface->decStrong(NULL);
    }

    dc->gl.wndSurface = (ANativeWindow *)sur;
    if (dc->gl.wndSurface != NULL) {
        dc->gl.wndSurface->incStrong(NULL);
        dc->gl.width = w;
        dc->gl.height = h;

        rsc->setWatchdogGL("eglCreateWindowSurface", __LINE__, __FILE__);
        dc->gl.egl.surface = eglCreateWindowSurface(dc->gl.egl.display, dc->gl.egl.config,
                                                    dc->gl.wndSurface, NULL);
        checkEglError("eglCreateWindowSurface");
        if (dc->gl.egl.surface == EGL_NO_SURFACE) {
            ALOGE("eglCreateWindowSurface returned EGL_NO_SURFACE");
        }

        rsc->setWatchdogGL("eglMakeCurrent", __LINE__, __FILE__);
        ret = eglMakeCurrent(dc->gl.egl.display, dc->gl.egl.surface,
                             dc->gl.egl.surface, dc->gl.egl.context);
        checkEglError("eglMakeCurrent", ret);
    }
    rsc->setWatchdogGL(NULL, 0, NULL);
    return true;
}

void rsdGLSwap(const android::renderscript::Context *rsc) {
    RsdHal *dc = (RsdHal *)rsc->mHal.drv;
    RSD_CALL_GL(eglSwapBuffers, dc->gl.egl.display, dc->gl.egl.surface);
}

void rsdGLSetPriority(const Context *rsc, int32_t priority) {
    if (priority > 0) {
        // Mark context as low priority.
        ALOGV("low pri");
    } else {
        ALOGV("normal pri");
    }
}

void rsdGLCheckError(const android::renderscript::Context *rsc,
                     const char *msg, bool isFatal) {
    GLenum err = glGetError();
    if (err != GL_NO_ERROR) {
        char buf[1024];
        snprintf(buf, sizeof(buf), "GL Error = 0x%08x, from: %s", err, msg);

        if (isFatal) {
            rsc->setError(RS_ERROR_FATAL_DRIVER, buf);
        } else {
            switch (err) {
            case GL_OUT_OF_MEMORY:
                rsc->setError(RS_ERROR_OUT_OF_MEMORY, buf);
                break;
            default:
                rsc->setError(RS_ERROR_DRIVER, buf);
                break;
            }
        }

        ALOGE("%p, %s", rsc, buf);
    }

}