#include <jni.h>
#include <errno.h>

#include <EGL/egl.h>
#include <GLES/gl.h>

#include <android/sensor.h>
#include <android/log.h>
#include <android_native_app_glue.h>

#include <pthread.h>

#include "CCDirector.h"
#include "CCApplication.h"
#include "CCEventType.h"
#include "support/CCNotificationCenter.h"
#include "CCFileUtilsAndroid.h"
#include "jni/JniHelper.h"

#define LOGI(...) ((void)__android_log_print(ANDROID_LOG_INFO, "cocos2dx/nativeactivity.cpp", __VA_ARGS__))
#define LOGW(...) ((void)__android_log_print(ANDROID_LOG_WARN, "cocos2dx/nativeactivity.cpp", __VA_ARGS__))

#define LOG_RENDER_DEBUG(...)
// #define LOG_RENDER_DEBUG(...)  ((void)__android_log_print(ANDROID_LOG_WARN, "cocos2dx/nativeactivity.cpp", __VA_ARGS__))

/**
 * Our saved state data.
 */
struct saved_state {
    float angle;
    int32_t x;
    int32_t y;
};

/**
 * Shared state for our app.
 */
struct engine {
    struct android_app* app;

    ASensorManager* sensorManager;
    const ASensor* accelerometerSensor;
    ASensorEventQueue* sensorEventQueue;

    int animating;
    EGLDisplay display;
    EGLSurface surface;
    EGLContext context;
    int32_t width;
    int32_t height;
    struct saved_state state;
};

#include "CCEGLView.h"
#include "draw_nodes/CCDrawingPrimitives.h"
#include "shaders/CCShaderCache.h"
#include "textures/CCTextureCache.h"

extern "C" void cocos_android_app_init(void);

typedef struct cocos_dimensions {
    int w;
    int h;
} cocos_dimensions;

static void jnihelper_init(JavaVM* vm) {
    LOGI("jnihelper_init(...)");
    pthread_t thisthread = pthread_self();
    LOGI("pthread_self() = %X", thisthread);

    cocos2d::JniHelper::setJavaVM(vm);
}

static void cocos_init(cocos_dimensions d, AAssetManager* assetmanager) {
    LOGI("cocos_init(...)");
    pthread_t thisthread = pthread_self();
    LOGI("pthread_self() = %X", thisthread);

    cocos2d::FileUtilsAndroid::setassetmanager(assetmanager);

    if (!cocos2d::Director::sharedDirector()->getOpenGLView())
    {
        cocos2d::EGLView *view = cocos2d::EGLView::sharedOpenGLView();
        view->setFrameSize(d.w, d.h);

        cocos_android_app_init();

        cocos2d::Application::getInstance()->run();
    }
    else
    {
        cocos2d::GL::invalidateStateCache();
        cocos2d::ShaderCache::getInstance()->reloadDefaultShaders();
        cocos2d::DrawPrimitives::init();
        cocos2d::TextureCache::reloadAllTextures();
        cocos2d::NotificationCenter::getInstance()->postNotification(EVNET_COME_TO_FOREGROUND, NULL);
        cocos2d::Director::getInstance()->setGLDefaultValues(); 
    }
}

/**
 * Initialize an EGL context for the current display.
 */
static cocos_dimensions engine_init_display(struct engine* engine) {
    cocos_dimensions r;
    r.w = -1;
    r.h = -1;

    // initialize OpenGL ES and EGL

    /*
     * Here specify the attributes of the desired configuration.
     * Below, we select an EGLConfig with at least 8 bits per color
     * component compatible with on-screen windows
     */
    const EGLint attribs[] = {
            EGL_SURFACE_TYPE, EGL_WINDOW_BIT,
            EGL_BLUE_SIZE, 5,
            EGL_GREEN_SIZE, 6,
            EGL_RED_SIZE, 5,
            EGL_DEPTH_SIZE, 16,
            EGL_STENCIL_SIZE, 8,
            EGL_NONE
    };
    EGLint w, h, dummy, format;
    EGLint numConfigs;
    EGLConfig config;
    EGLSurface surface;
    EGLContext context;

    EGLDisplay display = eglGetDisplay(EGL_DEFAULT_DISPLAY);

    eglInitialize(display, 0, 0);

    /* Here, the application chooses the configuration it desires. In this
     * sample, we have a very simplified selection process, where we pick
     * the first EGLConfig that matches our criteria */
    eglChooseConfig(display, attribs, &config, 1, &numConfigs);

    /* EGL_NATIVE_VISUAL_ID is an attribute of the EGLConfig that is
     * guaranteed to be accepted by ANativeWindow_setBuffersGeometry().
     * As soon as we picked a EGLConfig, we can safely reconfigure the
     * ANativeWindow buffers to match, using EGL_NATIVE_VISUAL_ID. */
    eglGetConfigAttrib(display, config, EGL_NATIVE_VISUAL_ID, &format);

    ANativeWindow_setBuffersGeometry(engine->app->window, 0, 0, format);

    surface = eglCreateWindowSurface(display, config, engine->app->window, NULL);

    const EGLint eglContextAttrs[] =
    {
        EGL_CONTEXT_CLIENT_VERSION, 2,
        EGL_NONE
    };

    context = eglCreateContext(display, config, NULL, eglContextAttrs);

    if (eglMakeCurrent(display, surface, surface, context) == EGL_FALSE) {
        LOGW("Unable to eglMakeCurrent");
        return r;
    }

    eglQuerySurface(display, surface, EGL_WIDTH, &w);
    eglQuerySurface(display, surface, EGL_HEIGHT, &h);

    engine->display = display;
    engine->context = context;
    engine->surface = surface;
    engine->width = w;
    engine->height = h;
    engine->state.angle = 0;

    // Initialize GL state.
    glHint(GL_PERSPECTIVE_CORRECTION_HINT, GL_FASTEST);
    glEnable(GL_CULL_FACE);
    glShadeModel(GL_SMOOTH);
    glDisable(GL_DEPTH_TEST);

    r.w = w;
    r.h = h;

    return r;
}

/**
 * Just the current frame in the display.
 */
static void engine_draw_frame(struct engine* engine) {
    LOGI("engine_draw_frame(...)");
    pthread_t thisthread = pthread_self();
    LOGI("pthread_self() = %X", thisthread);

    if (engine->display == NULL) {
        // No display.
        LOGW("engine_draw_frame : No display.");
        return;
    }

    cocos2d::Director::sharedDirector()->mainLoop();
    LOG_RENDER_DEBUG("engine_draw_frame : just called cocos' mainLoop()");

    /* // Just fill the screen with a color. */
    /* glClearColor(((float)engine->state.x)/engine->width, engine->state.angle, */
    /*         ((float)engine->state.y)/engine->height, 1); */
    /* glClear(GL_COLOR_BUFFER_BIT); */

    eglSwapBuffers(engine->display, engine->surface);
}

/**
 * Tear down the EGL context currently associated with the display.
 */
static void engine_term_display(struct engine* engine) {
    if (engine->display != EGL_NO_DISPLAY) {
        eglMakeCurrent(engine->display, EGL_NO_SURFACE, EGL_NO_SURFACE, EGL_NO_CONTEXT);
        if (engine->context != EGL_NO_CONTEXT) {
            eglDestroyContext(engine->display, engine->context);
        }
        if (engine->surface != EGL_NO_SURFACE) {
            eglDestroySurface(engine->display, engine->surface);
        }
        eglTerminate(engine->display);
    }
    engine->animating = 0;
    engine->display = EGL_NO_DISPLAY;
    engine->context = EGL_NO_CONTEXT;
    engine->surface = EGL_NO_SURFACE;
}

/**
 * Process the next input event.
 */
static int32_t engine_handle_input(struct android_app* app, AInputEvent* event) {
    struct engine* engine = (struct engine*)app->userData;
    if (AInputEvent_getType(event) == AINPUT_EVENT_TYPE_MOTION) {
        engine->animating = 1;
        engine->state.x = AMotionEvent_getX(event, 0);
        engine->state.y = AMotionEvent_getY(event, 0);
        return 1;
    }
    return 0;
}

/**
 * Process the next main command.
 */
static void engine_handle_cmd(struct android_app* app, int32_t cmd) {
    struct engine* engine = (struct engine*)app->userData;
    switch (cmd) {
        case APP_CMD_SAVE_STATE:
            // The system has asked us to save our current state.  Do so.
            engine->app->savedState = malloc(sizeof(struct saved_state));
            *((struct saved_state*)engine->app->savedState) = engine->state;
            engine->app->savedStateSize = sizeof(struct saved_state);
            break;
        case APP_CMD_INIT_WINDOW:
            // The window is being shown, get it ready.
            if (engine->app->window != NULL) {
                cocos_dimensions d = engine_init_display(engine);
                if ((d.w > 0) &&
                    (d.h > 0)) {
                    jnihelper_init(app->activity->vm);
                    cocos_init(d, app->activity->assetManager);
                }

                engine_draw_frame(engine);
            }
            break;
        case APP_CMD_TERM_WINDOW:
            // The window is being hidden or closed, clean it up.
            engine_term_display(engine);
            break;
        case APP_CMD_GAINED_FOCUS:
            // When our app gains focus, we start monitoring the accelerometer.
            if (engine->accelerometerSensor != NULL) {
                ASensorEventQueue_enableSensor(engine->sensorEventQueue,
                        engine->accelerometerSensor);
                // We'd like to get 60 events per second (in us).
                ASensorEventQueue_setEventRate(engine->sensorEventQueue,
                        engine->accelerometerSensor, (1000L/60)*1000);
            }

            if (cocos2d::Director::sharedDirector()->getOpenGLView()) {
                cocos2d::Application::sharedApplication()->applicationWillEnterForeground();
            }

            break;
        case APP_CMD_LOST_FOCUS:
            // When our app loses focus, we stop monitoring the accelerometer.
            // This is to avoid consuming battery while not being used.
            if (engine->accelerometerSensor != NULL) {
                ASensorEventQueue_disableSensor(engine->sensorEventQueue,
                        engine->accelerometerSensor);
            }

            cocos2d::Application::sharedApplication()->applicationDidEnterBackground();
            cocos2d::NotificationCenter::sharedNotificationCenter()->postNotification(EVENT_COME_TO_BACKGROUND, NULL);

            // Also stop animating.
            engine->animating = 0;
            engine_draw_frame(engine);
            break;
    }
}

/**
 * This is the main entry point of a native application that is using
 * android_native_app_glue.  It runs in its own thread, with its own
 * event loop for receiving input events and doing other things.
 */
void android_main(struct android_app* state) {
    struct engine engine;

    // Make sure glue isn't stripped.
    app_dummy();

    memset(&engine, 0, sizeof(engine));
    state->userData = &engine;
    state->onAppCmd = engine_handle_cmd;
    state->onInputEvent = engine_handle_input;
    engine.app = state;

    // Prepare to monitor accelerometer
    engine.sensorManager = ASensorManager_getInstance();
    engine.accelerometerSensor = ASensorManager_getDefaultSensor(engine.sensorManager,
            ASENSOR_TYPE_ACCELEROMETER);
    engine.sensorEventQueue = ASensorManager_createEventQueue(engine.sensorManager,
            state->looper, LOOPER_ID_USER, NULL, NULL);

    if (state->savedState != NULL) {
        // We are starting with a previous saved state; restore from it.
        engine.state = *(struct saved_state*)state->savedState;
    }

    // loop waiting for stuff to do.

    while (1) {
        // Read all pending events.
        int ident;
        int events;
        struct android_poll_source* source;

        // If not animating, we will block forever waiting for events.
        // If animating, we loop until all events are read, then continue
        // to draw the next frame of animation.
        while ((ident=ALooper_pollAll(engine.animating ? 0 : -1, NULL, &events,
                (void**)&source)) >= 0) {

            // Process this event.
            if (source != NULL) {
                source->process(state, source);
            }

            // If a sensor has data, process it now.
            if (ident == LOOPER_ID_USER) {
                if (engine.accelerometerSensor != NULL) {
                    ASensorEvent event;
                    while (ASensorEventQueue_getEvents(engine.sensorEventQueue,
                            &event, 1) > 0) {
                        LOG_RENDER_DEBUG("accelerometer: x=%f y=%f z=%f",
                                event.acceleration.x, event.acceleration.y,
                                event.acceleration.z);
                    }
                }
            }

            // Check if we are exiting.
            if (state->destroyRequested != 0) {
                engine_term_display(&engine);
                return;
            }
        }

        if (engine.animating) {
            // Done with events; draw next animation frame.
            engine.state.angle += .01f;
            if (engine.state.angle > 1) {
                engine.state.angle = 0;
            }

            // Drawing is throttled to the screen update rate, so there
            // is no need to do timing here.
            LOG_RENDER_DEBUG("android_main : engine.animating");
            engine_draw_frame(&engine);
        } else {
            LOG_RENDER_DEBUG("android_main : !engine.animating");
        }
    }
}