/*
	Spacebar: A FOSS re-implementation and extension of the Discord.com backend.
	Copyright (C) 2023 Spacebar and Spacebar Contributors
	
	This program is free software: you can redistribute it and/or modify
	it under the terms of the GNU Affero General Public License as published
	by the Free Software Foundation, either version 3 of the License, or
	(at your option) any later version.
	
	This program is distributed in the hope that it will be useful,
	but WITHOUT ANY WARRANTY; without even the implied warranty of
	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
	GNU Affero General Public License for more details.
	
	You should have received a copy of the GNU Affero General Public License
	along with this program.  If not, see <https://www.gnu.org/licenses/>.
*/

import { Payload, WebSocket } from "@spacebar/gateway";
import fs from "node:fs/promises";
import path from "node:path";

import { JSONReplacer } from "@spacebar/util";
import * as erlpack from "harmony-erlpack";

// don't care
// eslint-disable-next-line @typescript-eslint/no-explicit-any
const recurseJsonReplace = (json: any) => {
    for (const key in json) {
        // eslint-disable-next-line no-prototype-builtins
        if (!json.hasOwnProperty(key)) continue;

        json[key] = JSONReplacer.call(json, key, json[key]);

        if (typeof json[key] == "object" && json[key] !== null) json[key] = recurseJsonReplace(json[key]);
    }
    return json;
};

export async function Send(socket: WebSocket, data: Payload) {
    if (process.env.WS_VERBOSE) console.log(`[Websocket] Outgoing message: ${JSON.stringify(data)}`);

    if (process.env.WS_DUMP) {
        const id = socket.session_id || "unknown";

        await fs.mkdir(path.join("dump", id), {
            recursive: true,
        });
        await fs.writeFile(path.join("dump", id, `${Date.now()}.out.json`), JSON.stringify(data, null, 2));
    }

    let buffer: Buffer | string;
    if (socket.encoding === "etf" && erlpack) {
        // Erlpack doesn't like Date objects, encodes them as {}
        data = recurseJsonReplace(data);
        buffer = Buffer.from(erlpack.pack(data));
    }
    // TODO: encode circular object
    else if (socket.encoding === "json") buffer = JSON.stringify(data, JSONReplacer);
    else return;

    // TODO: compression
    if (socket.compress === "zlib-stream") {
        buffer = socket.deflate!.process(buffer) as Buffer;
    } else if (socket.compress === "zstd-stream") {
        if (typeof buffer === "string") buffer = Buffer.from(buffer as string);

        buffer = (await socket.zstdEncoder!.encode(buffer as Buffer)) as Buffer;
    }

    return new Promise((res, rej) => {
        if (socket.readyState !== 1) {
            // return rej("socket not open");
            socket.close();
            return;
        }

        socket.send(buffer, (err) => {
            if (err) return rej(err);
            return res(null);
        });
    });
}