#include <jni.h>
#include <android/native_window_jni.h>
#include <android/native_window.h>
#include <android/log.h>

#define LOG_TAG "NativeRenderer"
#define LOGI(...) __android_log_print(ANDROID_LOG_INFO, LOG_TAG, __VA_ARGS__)
#define LOGE(...) __android_log_print(ANDROID_LOG_ERROR, LOG_TAG, __VA_ARGS__)

static ANativeWindow* window = nullptr;

extern "C" JNIEXPORT void JNICALL
Java_bums_lunatic_launcher_wall_NativeRenderer_nativeInit(JNIEnv* env, jobject, jobject surface) {
    if (window != nullptr) {
        ANativeWindow_release(window);
        window = nullptr;
    }
    window = ANativeWindow_fromSurface(env, surface);
    LOGI("Native window initialized");
}

extern "C" JNIEXPORT void JNICALL
Java_bums_lunatic_launcher_wall_NativeRenderer_nativeRender(
        JNIEnv* env, jobject, jintArray pixels, jint width, jint height,
        jfloat offsetX, jfloat offsetY, jfloat fadeAlpha) {

    if (!window) return;

    ANativeWindow_Buffer buffer;
    if (ANativeWindow_lock(window, &buffer, nullptr) < 0) {
        LOGE("Failed to lock native window");
        return;
    }

    jint* srcPixels = env->GetIntArrayElements(pixels, nullptr);
    if (!srcPixels) {
        ANativeWindow_unlockAndPost(window);
        return;
    }

    uint32_t* dstPixels = (uint32_t*)buffer.bits;
    int stride = buffer.stride;

    int offsetXInt = static_cast<int>(offsetX);
    int offsetYInt = static_cast<int>(offsetY);

    for (int y = 0; y < buffer.height; y++) {
        int srcY = y - offsetYInt;
        if (srcY < 0 || srcY >= height) continue;

        for (int x = 0; x < buffer.width; x++) {
            int srcX = x - offsetXInt;
            if (srcX < 0 || srcX >= width) continue;

            uint32_t pixel = srcPixels[srcY * width + srcX];

            uint8_t alpha = static_cast<uint8_t>(fadeAlpha * 255);
            uint8_t r = (pixel >> 16) & 0xFF;
            uint8_t g = (pixel >> 8) & 0xFF;
            uint8_t b = pixel & 0xFF;

            r = (r * alpha) / 255;
            g = (g * alpha) / 255;
            b = (b * alpha) / 255;

            dstPixels[y * stride + x] = (0xFF << 24) | (r << 16) | (g << 8) | b;
        }
    }

    env->ReleaseIntArrayElements(pixels, srcPixels, JNI_ABORT);

    ANativeWindow_unlockAndPost(window);
}

extern "C" JNIEXPORT void JNICALL
Java_bums_lunatic_launcher_wall_NativeRenderer_nativeDestroy(JNIEnv*, jobject) {
    if (window) {
        ANativeWindow_release(window);
        window = nullptr;
        LOGI("Native window released");
    }
}