import Endian from '/endian';
import {MIN_WIDTH, MIN_HEIGHT, PACKET_ID_HELLO, PACKET_ID_SEND_FRAME, PACKET_ID_KEY_DOWN} from '/constants';

function concatU8Array(array1: Uint8Array, array2: Uint8Array) {
    const final_array = new Uint8Array(array1.length + array2.length);
    final_array.set(array1);
    final_array.set(array2, array1.length);
    return final_array;
}

export function sendHello(websocket: WebSocket, rom_array: Uint8Array, savestate_array: Uint8Array) {
    console.log('Sending hello.');
    const length_rom = BigInt(rom_array.length);
    const length_savestate = BigInt(savestate_array.length);
    const raw_data = 
    concatU8Array(
        concatU8Array(
            concatU8Array(Endian.u64ToByteArrayBigEndian(length_rom), rom_array),
            Endian.u64ToByteArrayBigEndian(length_savestate)
        ),
        savestate_array
    );
    sendPacket(websocket, PACKET_ID_HELLO, raw_data);
}

export function sendKeyDown(websocket: WebSocket, isDown: boolean, key: number) {
    console.log('Sending keyDown.');
    console.log(PACKET_ID_KEY_DOWN);
    const isDownArray = new Uint8Array(1);
    isDownArray[0] = isDown ? 1: 0;
    const rawData = concatU8Array(isDownArray, Endian.u32ToByteArrayBigEndian(key));
    console.log(rawData.length);
    sendPacket(websocket, PACKET_ID_KEY_DOWN, rawData);
}

export function sendPacket(websocket: WebSocket, id: bigint, raw_data: Uint8Array) {
    const packet_u8 = concatU8Array( 
        concatU8Array(Endian.u64ToByteArrayBigEndian(id), Endian.u64ToByteArrayBigEndian(BigInt(raw_data.length))),
        raw_data
    );
    const packet_buffer = packet_u8.buffer;
    console.log('Sending packet');
    websocket.send(packet_buffer);
}

export function handleSendFrame(raw_data: Uint8Array, canvas: HTMLCanvasElement, ctx: CanvasRenderingContext2D, printingFrame: boolean, setPrintingFrame: (c: boolean) => void) {
    if (printingFrame) {
        return;
    }
    setPrintingFrame(true);
    let data: Uint8Array | null = raw_data;
    const stride = Endian.byteArrayToU32BigEndian(data.slice(0, 4));
    data = data.slice(4, data.length);
    const output_buffer_size = Endian.byteArrayToU64BigEndian(data.slice(0, 8));
    data = data.slice(8, data.length);
    const img_data = ctx.createImageData(MIN_WIDTH, MIN_HEIGHT);
    const img_data_u8 = new Uint8Array(img_data.data.buffer);
    for (let i = 0; i<data.length; i++) {
        if (i % 4 == 3) {
            img_data_u8[i] = 255;
            continue;
        }
        img_data_u8[i] = data[i];
    }
    data = null;
    createImageBitmap(img_data).then((bitmap) => drawBitmap(bitmap, canvas, ctx, printingFrame));
}

function drawBitmap(bitmap: ImageBitmap, canvas: HTMLCanvasElement, ctx: CanvasRenderingContext2D, printingFrame: boolean) {
    ctx.drawImage(bitmap, 0, 0, canvas.width, canvas.height);
    printingFrame = false;
}