const cache = {};

const opcodesInterestedIn = {
  //  200: true, // ammunition change
    164: true, // item usage
    163: true, // gets attacked
    162: true, // authorless hp change
    160: true, // design change
    151: true, // map change state
    148: true, // equipment change
    131: true, // rewards
    133: true, // entity disappears
    134: true // entity appears
};

function packet(packetsToAdd, batched, id, metadataToAdd) {
    if (!(packetsToAdd instanceof Array)) packetsToAdd = [packetsToAdd];
    
    if (!cache[id]) cache[id] = new ArrayBuffer(1024, { maxByteLength: 65536 });

    const playerBehaviourContext = global.actionContext.getElement(id);

    const targetBuffer = cache[id];
    const targetArray = new Uint8Array(targetBuffer);
    let offset = batched.offset;

    packetsToAdd.forEach((packet, i) => {
        const newSize = offset + packet.byteLength;
        if (newSize > targetBuffer.byteLength) {
            const newBufferSize = Math.pow(2, Math.ceil(Math.log(newSize) / Math.log(2)));
            targetBuffer.resize(newBufferSize);
        };

        const newArray = new Uint8Array(packet);
        if (opcodesInterestedIn[newArray[0]]) {
            const metadata = {
                ts: new Date(),
                pid: id,
                metadata: metadataToAdd && metadataToAdd[i] ? metadataToAdd[i] : {}
            };
        
            playerBehaviourContext.add(metadata);
        };

        targetArray.set(newArray, offset);
        offset += packet.byteLength;
    });

    return {
        packet: targetBuffer,
        offset
    };
};

module.exports = packet;