cesr/dist/message.js

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import { Attachments } from "./attachments.js";
import { decodeUtf8, encodeUtf8 } from "./encoding-utf8.js";
import { VersionString } from "./version-string.js";
function encode(init) {
    const { v, ...payload } = init;
    if (typeof v !== "string") {
        throw new Error(`Version field 'v' in payload must be a string, got ${typeof v}`);
    }
    const tmpversion = VersionString.parse(v);
    const tmp = encodeUtf8(JSON.stringify({
        v: tmpversion.text,
        ...payload,
    }));
    const version = new VersionString({
        protocol: tmpversion.protocol,
        major: tmpversion.major,
        minor: tmpversion.minor,
        kind: tmpversion.kind,
        legacy: tmpversion.legacy,
        size: tmp.length,
    });
    const raw = encodeUtf8(JSON.stringify({
        v: version.text,
        ...payload,
    }));
    return raw;
}
function read(input) {
    if (input.length === 0) {
        return null;
    }
    if (input[0] !== 0x7b) {
        const preview = decodeUtf8(input.slice(0, 20));
        throw new Error(`Expected JSON starting with '{' (0x7b), got: "${preview}"`);
    }
    if (input.length < 25) {
        return null;
    }
    const version = VersionString.extract(input.slice(0, 24));
    if (input.length < version.size) {
        return null;
    }
    const frame = input.slice(0, version.size);
    return JSON.parse(decodeUtf8(frame));
}
export class Message {
    #attachments;
    #raw;
    body;
    constructor(body, attachments) {
        this.#raw = encode(body);
        this.body = JSON.parse(decodeUtf8(this.#raw));
        this.#attachments = new Attachments(attachments ?? {});
    }
    text() {
        return decodeUtf8(this.#raw);
    }
    get raw() {
        return this.#raw;
    }
    get version() {
        if (!this.body.v || typeof this.body.v !== "string") {
            throw new Error("Payload does not contain a valid version string 'v'");
        }
        return VersionString.parse(this.body.v);
    }
    get attachments() {
        return this.#attachments;
    }
    set attachments(value) {
        this.#attachments = new Attachments(value);
    }
    static parse(input) {
        const body = read(input);
        if (body === null) {
            return null;
        }
        return new Message(body);
    }
    static encode(init) {
        return encode(init);
    }
    static from(body) {
        return new Message(body);
    }
}