Socio/core/utils.ts

//I ask not for a lighter burden, but for broader shoulders. -Atlas, when asking Zeus for sympathy.

import type { QueryMarker } from "./types.d.ts";
import type { SocioStringObj } from "./sql-parsing.js";

// these are not types, but compile to js dicts, so cannot be imported as types, but also cannot be declared in types.d.ts, bcs that doesnt produce a js file
export enum ServerMessageKind {
    SUB,
    UNSUB,
    SQL,
    PING,
    AUTH,
    GET_PERM,
    PROP_SUB,
    PROP_UNSUB,
    PROP_GET,
    PROP_SET,
    PROP_REG,
    SERV,
    ADMIN,
    RECON,
    UP_FILES,
    GET_FILES,
    IDENTIFY,
    DISCOVERY,
    RPC,
    OK,
};
export enum ClientMessageKind {
    CON,
    UPD,
    PONG,
    AUTH,
    GET_PERM,
    RES,
    PROP_UPD,
    PROP_DROP,
    CMD,
    RECON,
    RECV_FILES,
    TIMEOUT,
    RPC,
};

//socio string marker utils
export const socio_string_markers_regex = /--(?<markers>(?:-?(?:socio|auth|perm))*)/i;
export function SocioStringParse(str: string): SocioStringObj {
    const markers = str.match(socio_string_markers_regex)?.groups?.markers;
    return { str, markers: markers ? markers.split('-') : [] };
}
export function SocioMarkerHas(marker: QueryMarker, { parsed = null, str = '' }: { parsed?: string[] | null, str?: string }) {
    return marker ? (parsed ? parsed.includes(marker) : (str ? SocioStringParse(str).markers.includes(marker) : false)) : false
}

// TS/JS helpers
// Helper to dynamically generate default hooks dict of undefineds
export function initLifecycleHooks<T extends Record<string, unknown>>(): T {
    return {} as T; // Use an empty object to simulate "undefined" for all properties
}

//misc
export function sleep(seconds: number = 2) {
    return new Promise(res => setTimeout(res, seconds * 1000))
}
export function clamp(x: number, min: number, max: number) {
    return Math.min(Math.max(x, min), max);
}

//Credit: https://stackoverflow.com/a/40577337/8422448 (modified)
export function GetAllMethodNamesOf(obj: any): string[] {
    const methods: Set<string> = new Set();
    while (obj = Reflect.getPrototypeOf(obj)) {
        Reflect.ownKeys(obj)
            .map(k => k.toString()) //bcs some might be symbols
            .filter(k =>
                k != 'constructor'
                && !k.startsWith('__')
            ).forEach((k) => methods.add(k));
    }
    return [...methods];
}

//copy pasted from WS repo: https://github.com/websockets/ws/blob/master/doc/ws.md#new-websocketserveroptions-callback:~:text=subprotocols%20is%20used.-,perMessageDeflate,-can%20be%20used
export const perMessageDeflate = {
    zlibDeflateOptions: {
        // See zlib defaults.
        chunkSize: 1024,
        memLevel: 7,
        level: 3
    },
    zlibInflateOptions: {
        chunkSize: 10 * 1024
    },
    // Other options settable:
    clientNoContextTakeover: true, // Defaults to negotiated value.
    serverNoContextTakeover: true, // Defaults to negotiated value.
    serverMaxWindowBits: 10, // Defaults to negotiated value.
    // Below options specified as default values.
    concurrencyLimit: 10, // Limits zlib concurrency for perf.
    threshold: 1024 // Size (in bytes) below which messages
    // should not be compressed if context takeover is disabled.
}

import { encode, decode } from "@msgpack/msgpack";
export function socio_encode(o: any) { return encode(o); }
export function socio_decode(buffer: Uint8Array) { return decode(buffer) as any; }

// Credit: https://gist.github.com/jlevy/c246006675becc446360a798e2b2d781 (modified) 
// super simple, naive, yet fast way to generate a hash for a subscription query. Used to keep a cache while in the core Update function.
export function FastHash(str: string) {
    let hash = 0;
    for (let i = 0; i < str.length; i++) {
        hash = ((hash << 5) - hash) + str.charCodeAt(i);
        hash = hash & hash;
    }
    return hash;
}