import { Api } from "../api";
import type { BinaryReader } from "../../extensions";
import { GZIPPacked } from "./";
import bigInt from "big-integer";

export class RPCResult {
    static CONSTRUCTOR_ID = 0xf35c6d01;
    static classType = "constructor";
    private CONSTRUCTOR_ID: number;
    private reqMsgId: bigInt.BigInteger;
    private body?: Buffer;
    private error?: Api.RpcError;
    private classType: string;

    constructor(
        reqMsgId: bigInt.BigInteger,
        body?: Buffer,
        error?: Api.RpcError
    ) {
        this.CONSTRUCTOR_ID = 0xf35c6d01;
        this.reqMsgId = reqMsgId;
        this.body = body;
        this.error = error;
        this.classType = "constructor";
    }

    static async fromReader(reader: BinaryReader) {
        const msgId = reader.readLong();
        const innerCode = reader.readInt(false);
        if (innerCode === Api.RpcError.CONSTRUCTOR_ID) {
            return new RPCResult(
                msgId,
                undefined,
                Api.RpcError.fromReader(reader)
            );
        }
        if (innerCode === GZIPPacked.CONSTRUCTOR_ID) {
            return new RPCResult(
                msgId,
                (await GZIPPacked.fromReader(reader)).data
            );
        }
        reader.seek(-4);
        // This reader.read() will read more than necessary, but it's okay.
        // We could make use of MessageContainer's length here, but since
        // it's not necessary we don't need to care about it.
        return new RPCResult(msgId, reader.read(), undefined);
    }
}