/*
 * Copyright (C) 2010 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.
 *
 */

//BEGIN_INCLUDE(all)
#include <initializer_list>
#include <memory>
#include <jni.h>
#include <errno.h>
#include <cassert>
#include <EGL/egl.h>
#include <EGL/eglext.h>

#include "pch.h"
#include "app.h"
#include "asset.h"
#include "keymap.h"

typedef void (*GLDEBUGPROC)(GLenum source,
    GLenum type,
    GLuint id,
    GLenum severity,
    GLsizei length,
    const GLchar* message,
    const void* userParam);

typedef void (*fnDebugMessageCallback)(GLDEBUGPROC callback, const void* userParam);

#define GL_DEBUG_SEVERITY_HIGH                              0x9146
#define GL_DEBUG_SEVERITY_MEDIUM                            0x9147
#define GL_DEBUG_SEVERITY_LOW                               0x9148
#define GL_DEBUG_SEVERITY_NOTIFICATION                      0x826B

#define GL_DEBUG_OUTPUT                                     0x92E0
#define GL_DEBUG_OUTPUT_SYNCHRONOUS                         0x8242

/**
 * 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;
};

/**
 * Initialize an EGL context for the current display.
 */
static int engine_init_display(struct engine* engine) {
    // initialize OpenGL ES and EGL
    App::I.initLog();

    /*
     * 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, 8,
            EGL_GREEN_SIZE, 8,
            EGL_RED_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.
     * find the best match if possible, otherwise use the very first one
     */
    eglChooseConfig(display, attribs, nullptr,0, &numConfigs);
    std::unique_ptr<EGLConfig[]> supportedConfigs(new EGLConfig[numConfigs]);
    assert(supportedConfigs);
    eglChooseConfig(display, attribs, supportedConfigs.get(), numConfigs, &numConfigs);
    assert(numConfigs);
    auto i = 0;
    for (; i < numConfigs; i++) {
        auto& cfg = supportedConfigs[i];
        EGLint r, g, b, d;
        if (eglGetConfigAttrib(display, cfg, EGL_RED_SIZE, &r)   &&
            eglGetConfigAttrib(display, cfg, EGL_GREEN_SIZE, &g) &&
            eglGetConfigAttrib(display, cfg, EGL_BLUE_SIZE, &b)  &&
            eglGetConfigAttrib(display, cfg, EGL_DEPTH_SIZE, &d) &&
            r == 8 && g == 8 && b == 8 && d == 0 ) {

            config = supportedConfigs[i];
            break;
        }
    }
    if (i == numConfigs) {
        config = supportedConfigs[0];
    }

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

    const EGLint attribs_test[] = {
        EGL_CONTEXT_CLIENT_VERSION, 2,
        EGL_CONTEXT_FLAGS_KHR, EGL_CONTEXT_OPENGL_DEBUG_BIT_KHR | EGL_CONTEXT_OPENGL_FORWARD_COMPATIBLE_BIT_KHR,
        //EGL_CONTEXT_OPENGL_PROFILE_MASK_KHR, EGL_CONTEXT_OPENGL_CORE_PROFILE_BIT_KHR,
        EGL_NONE
    };

    context = eglCreateContext(display, config, EGL_NO_CONTEXT, attribs_test);

    if (context == EGL_NO_CONTEXT)
    {
        LOG("EGL: debug and forward context failed");
        const EGLint attribs_test[] = {
            EGL_CONTEXT_CLIENT_VERSION, 2,
            EGL_CONTEXT_FLAGS_KHR, EGL_CONTEXT_OPENGL_FORWARD_COMPATIBLE_BIT_KHR,
            EGL_NONE
        };
        context = eglCreateContext(display, config, EGL_NO_CONTEXT, attribs_test);
        if (context == EGL_NO_CONTEXT)
        {
            LOG("EGL: only forward context failed");
            const EGLint attribs_test[] = {
                EGL_CONTEXT_CLIENT_VERSION, 2,
                EGL_CONTEXT_FLAGS_KHR, EGL_CONTEXT_OPENGL_DEBUG_BIT_KHR,
                //EGL_CONTEXT_OPENGL_PROFILE_MASK_KHR, EGL_CONTEXT_OPENGL_CORE_PROFILE_BIT_KHR,
                EGL_NONE
            };
            context = eglCreateContext(display, config, EGL_NO_CONTEXT, attribs_test);
            if (context == EGL_NO_CONTEXT)
            {
                LOG("EGL: only debug context failed");
                const EGLint attribs_test[] = {
                    EGL_CONTEXT_CLIENT_VERSION, 2,
                    EGL_NONE
                };
                context = eglCreateContext(display, config, EGL_NO_CONTEXT, attribs_test);
                if (context == EGL_NO_CONTEXT)
                {
                    LOG("EGL: all the context creation failed");
                }
                else
                {
                    LOG("EGL: created simple context");
                }
            }
            else
            {
                LOG("EGL: created only debug context");
            }
        }
        else
        {
            LOG("EGL: created only forward context");
        }
    }
    else
    {
        LOG("EGL: created debug and forward context");
    }

    if (eglMakeCurrent(display, surface, surface, context) == EGL_FALSE) {
        LOG("Unable to eglMakeCurrent");
        return -1;
    }

    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;

    // Check openGL on the system
    auto opengl_info = { GL_VENDOR, GL_RENDERER, GL_VERSION/*, GL_EXTENSIONS*/ };
    for (auto name : opengl_info) {
        auto info = glGetString(name);
        LOG("OpenGL Info: %s", info);
    }

    GLint n_exts;
    std::map<std::string, bool> ext_map;
    glGetIntegerv(GL_NUM_EXTENSIONS, &n_exts);
    for (int i = 0; i < n_exts; i++)
    {
        ext_map.emplace((char*)glGetStringi(GL_EXTENSIONS, i), true);
    }

    //const char* ext = (const char*) glGetString(GL_EXTENSIONS);
    //int ext_len = strlen(ext);
    //static char ext_name[256];
    //int ext_name_i = 0;
    //for (int i = 0; i < ext_len; i++)
    //{
    //    char c = ext[i];
    //    if (c == ' ')
    //    {
    //        ext_map.emplace(std::string(ext_name, ext_name_i), true);
    //        ext_name_i = 0;
    //    }
    //    else
    //    {
    //        ext_name[ext_name_i++] = c;
    //    }
    //}

    if (ext_map.count("GL_KHR_debug"))
    {
        LOG("GL_KHR_debug supported");
        auto glDebugMessageCallback = (fnDebugMessageCallback)eglGetProcAddress("glDebugMessageCallbackKHR");
        if (glDebugMessageCallback)
        {
            LOG("glDebugMessageCallback proc found at %p", glDebugMessageCallback);
            glDebugMessageCallback([](GLenum source, GLenum type, GLuint id,
                GLenum severity, GLsizei length, const GLchar* message, const void* userParam)
            {
                //if (severity == GL_DEBUG_SEVERITY_MEDIUM || severity == GL_DEBUG_SEVERITY_HIGH)
                {
                    LOG("OPENGL: %.*s", length, message);
                }
            }, nullptr);
            glEnable(GL_DEBUG_OUTPUT);
            glEnable(GL_DEBUG_OUTPUT_SYNCHRONOUS);
        }
        else
        {
            LOG("glDebugMessageCallback proc NOT FOUND");
        }
    }


    int ret = -1;
    FILE* file = popen("getprop", "r");
    std::map<std::string, std::string> os_props;
    if (file)
    {
        char output[100];
        while (fgets(output, sizeof(output), file) != nullptr)
        {
            int i = 0;
            int l = strlen(output);
            char buf[64];
            int j = 0;
            while (i < l && output[i] != '[') i++;
            i++;
            while (i < l && output[i] != ']') { buf[j++] = output[i]; i++; }
            std::string key(buf, j);
            j = 0;
            while (i < l && output[i] != '[') i++;
            i++;
            while (i < l && output[i] != ']') { buf[j++] = output[i]; i++; }
            os_props[key] = std::string(buf, j);
            //LOG("PROP: %s -> %s", key.c_str(), os_props[key].c_str());
        }
        pclose(file);
    }
    LOG("PROP Android Version: %s", os_props["ro.build.version.release"].c_str());
    LOG("PROP Android SDK: %s", os_props["ro.build.version.sdk"].c_str());
    LOG("PROP Country Code: %s", os_props["ro.csc.country_code"].c_str());
    LOG("PROP ABI: %s", os_props["ro.product.cpu.abilist"].c_str());
    LOG("PROP Brand: %s", os_props["ro.product.brand"].c_str());
    LOG("PROP Maker: %s", os_props["ro.product.manufacturer"].c_str());
    LOG("PROP Mode: %s", os_props["ro.product.model"].c_str());
    //LOG("PROP: %s", os_props[""].c_str());
    //LOG("PROP: %s", os_props[""].c_str());
    //LOG("PROP: %s", os_props[""].c_str());

    // Initialize GL state.
    //glHint(GL_PERSPECTIVE_CORRECTION_HINT, GL_FASTEST);
    //glEnable(GL_CULL_FACE);
    //glShadeModel(GL_SMOOTH);
    glDisable(GL_DEPTH_TEST);
    //glEnableClientState(GL_VERTEX_ARRAY);
    Asset::m_am = engine->app->activity->assetManager;
    App::I.data_path = "/sdcard/PanoPainter";// engine->app->activity->externalDataPath;
    App::I.width = w;
    App::I.height = h;
    App::I.init();

    LOG("All ready");
    engine->animating = 1;
    ANativeActivity_showSoftInput(engine->app->activity, ANATIVEACTIVITY_SHOW_SOFT_INPUT_FORCED);

    return 0;
}

/**
 * Just the current frame in the display.
 */
static void engine_draw_frame(struct engine* engine) {
    if (engine->display == NULL)
        return;

    glClearColor(.1f, .1f, .1f, 1.f);
    glViewport(0, 0, (GLsizei)engine->width, (GLsizei)engine->height);
    glClear(GL_COLOR_BUFFER_BIT);

    App::I.update(0);

    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;
    int32_t eventType = AInputEvent_getType(event);
    //LOG("event type: %d", eventType);
    switch (eventType) {
    case AINPUT_EVENT_TYPE_MOTION:
//         switch (AInputEvent_getSource(event)) {
//         case AINPUT_SOURCE_STYLUS:
//         case AINPUT_SOURCE_TOUCHSCREEN:
    {
        int action = AKeyEvent_getAction(event) & AMOTION_EVENT_ACTION_MASK;
        int32_t index = (action & AMOTION_EVENT_ACTION_POINTER_INDEX_MASK)
                        >> AMOTION_EVENT_ACTION_POINTER_INDEX_SHIFT;
        int pointer_id = AMotionEvent_getPointerId(event, index);
        int32_t count = AMotionEvent_getPointerCount(event);
        auto findPointer = [](int id, AInputEvent* event)
        {
            int32_t count = AMotionEvent_getPointerCount(event);
            int ret = -1;
            for (int i = 0; i < count; i++)
            {
                //LOG("pointer %d id %d == %d", i, id, AMotionEvent_getPointerId(event, i));
                if (AMotionEvent_getPointerId(event, i) == id)
                    ret = i;
            }
            return ret;
            return -1;
        };
        struct Pointer
        {
            int id = -1;
            int idx;
            glm::vec2 pos;
        };
        static Pointer p0, p1;
        static int tracked = 0;
        //LOG("event source: %d", AInputEvent_getSource(event));
        //LOG("pointer id %d count %d", pointer_id, count);
        MouseEvent e;
        switch (action) {
        case AMOTION_EVENT_ACTION_DOWN:
        {
            float y = AMotionEvent_getY(event, 0);
            float x = AMotionEvent_getX(event, 0);
            p0.id = AMotionEvent_getPointerId(event, 0);
            p0.pos = {x, y};
                p0.idx = index;
            App::I.mouse_down(0, x, y);
            tracked = 1;
            //LOG("first down");
            return 1;
        }
        case AMOTION_EVENT_ACTION_POINTER_DOWN:
        {
            //LOG("pointer down index %d", index);
            if (count == 2)
            {
                float y = AMotionEvent_getY(event, 1);
                float x = AMotionEvent_getX(event, 1);
                p1.id = AMotionEvent_getPointerId(event, 1);
                p1.idx = index;
                p1.pos = {x, y};
                tracked = 2;
                //LOG("second down");
                App::I.mouse_cancel(0);
                App::I.gesture_start(p0.pos, p1.pos);
            }
            return 1;
        }
        case AMOTION_EVENT_ACTION_UP:
        {
            float y = AMotionEvent_getY(event, 0);
            float x = AMotionEvent_getX(event, 0);
            p0.id = -1;
            p1.id = -1;
            if (tracked == 1)
                App::I.mouse_up(0, x, y);
            tracked = 0;
            //LOG("first up");
            return 1;
        }
        case AMOTION_EVENT_ACTION_POINTER_UP:
            if (p1.id == AMotionEvent_getPointerId(event, 1))
            {
                p1.id = -1;
                //LOG("second up");
                App::I.gesture_end();
            }
            return 1;
        case AMOTION_EVENT_ACTION_HOVER_MOVE: // pen move before touching
        {
            float y = AMotionEvent_getY(event, 0);
            float x = AMotionEvent_getX(event, 0);
            App::I.mouse_move(x, y);
            //LOG("single move");
            return 1;
        }
        case AMOTION_EVENT_ACTION_MOVE:
            if (count == 1 && tracked == 1)
            {
                float y = AMotionEvent_getY(event, 0);
                float x = AMotionEvent_getX(event, 0);
                App::I.mouse_move(x, y);
                //LOG("single move");
            }
            else if (count == 2)
            {
                int idx = findPointer(pointer_id, event);
                //LOG("pointer move index %d", idx);
                if (p0.idx == idx)
                {
                    //LOG("first move");
                    float y = AMotionEvent_getY(event, 0);
                    float x = AMotionEvent_getX(event, 0);
                    p0.pos = {x, y};
                }
                if (p1.idx == idx)
                {
                    //LOG("second move");
                    float x = AMotionEvent_getX(event, 1);
                    float y = AMotionEvent_getY(event, 1);
                    p1.pos = {x, y};
                }
                App::I.gesture_move(p0.pos, p1.pos);
            }
            return 1;
        default:
            //LOG("motion action: %d", action);
            break;
        }
    }
//             break;
//         } // end switch
        break;
    case AINPUT_EVENT_TYPE_KEY:
    {
        int32_t key_val = AKeyEvent_getKeyCode(event);
        LOG("Received key event: %d\n", key_val);
        App::I.key_down(convert_key(key_val));
        return 1;
    }
    } // end switch
    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) {
                engine_init_display(engine);
                engine_draw_frame(engine);
            }
            break;
        case APP_CMD_TERM_WINDOW:
            // The window is being hidden or closed, clean it up.
            App::I.terminate();
            engine_term_display(engine);
            //exit(0);
            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);
            }
            engine->animating = 1;
            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);
            }
            // 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;
    }

    //App::I.create();

    // 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.
        bool used = false;
        while (!used && (ident=ALooper_pollAll(-1, NULL, &events,
                                      (void**)&source)) >= 0) {

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

            // 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) {
                        // LOGI("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.
            engine_draw_frame(&engine);
        }
    }
}
//END_INCLUDE(all)