node-gamedig/protocols/samp.js

import Core from './core.js';

export default class samp extends Core {
    constructor() {
        super();
        this.encoding = 'win1252';
        this.magicHeader = 'SAMP';
        this.responseMagicHeader = null;
        this.isVcmp = false;
    }

    async run(state) {
        // read info
        {
            const reader = await this.sendPacket('i');
            if (this.isVcmp) {
                const consumed = reader.part(12);
                state.raw.version = this.reader(consumed).string();
            }
            state.password = !!reader.uint(1);
            state.raw.numplayers = reader.uint(2);
            state.maxplayers = reader.uint(2);
            state.name = reader.pascalString(4);
            state.raw.gamemode = reader.pascalString(4);
            state.raw.map = reader.pascalString(4);
        }

        // read rules
        if (!this.isVcmp) {
            const reader = await this.sendPacket('r');
            const ruleCount = reader.uint(2);
            state.raw.rules = {};
            for(let i = 0; i < ruleCount; i++) {
                const key = reader.pascalString(1);
                const value = reader.pascalString(1);
                state.raw.rules[key] = value;
            }
        }

        // read players
        // don't even bother if > 100 players, because the server won't respond
        let gotPlayerData = false;
        if (state.raw.numplayers < 100) {
            if (this.isVcmp) {
                const reader = await this.sendPacket('c', true);
                if (reader !== null) {
                    gotPlayerData = true;
                    const playerCount = reader.uint(2);
                    for(let i = 0; i < playerCount; i++) {
                        const player = {};
                        player.name = reader.pascalString(1);
                        state.players.push(player);
                    }
                }
            } else {
                const reader = await this.sendPacket('d', true);
                if (reader !== null) {
                    gotPlayerData = true;
                    const playerCount = reader.uint(2);
                    for(let i = 0; i < playerCount; i++) {
                        const player = {};
                        player.id = reader.uint(1);
                        player.name = reader.pascalString(1);
                        player.score = reader.int(4);
                        player.ping = reader.uint(4);
                        state.players.push(player);
                    }
                }
            }
        }
        if (!gotPlayerData) {
            state.players.setNum(state.raw.numplayers);
        }
    }
    async sendPacket(type,allowTimeout) {
        const outBuffer = Buffer.alloc(11);
        outBuffer.write(this.magicHeader,0, 4);
        const ipSplit = this.options.address.split('.');
        outBuffer.writeUInt8(parseInt(ipSplit[0]),4);
        outBuffer.writeUInt8(parseInt(ipSplit[1]),5);
        outBuffer.writeUInt8(parseInt(ipSplit[2]),6);
        outBuffer.writeUInt8(parseInt(ipSplit[3]),7);
        outBuffer.writeUInt16LE(this.options.port,8);
        outBuffer.writeUInt8(type.charCodeAt(0),10);

        const checkBuffer = Buffer.from(outBuffer);
        if (this.responseMagicHeader) {
            checkBuffer.write(this.responseMagicHeader, 0, 4);
        }

        return await this.udpSend(
            outBuffer,
            (buffer) => {
                const reader = this.reader(buffer);
                for(let i = 0; i < checkBuffer.length; i++) {
                    if(checkBuffer.readUInt8(i) !== reader.uint(1)) return;
                }
                return reader;
            },
            () => {
                if(allowTimeout) {
                    return null;
                }
            }
        );
    }
}