import { ChildProcess, spawn, StdioOptions } from 'child_process';
import { existsSync, mkdirSync } from 'fs';
import { rimraf } from 'rimraf';
import { Stream } from 'stream';
import { fileDescriptorFromStream, pathFromRoot } from './ActionUtilities';

export namespace Logger {
    const logPath = pathFromRoot('./logs');

    export async function initialize() {
        if (existsSync(logPath)) {
            if (!process.env.SPAWNED) {
                await new Promise<any>(resolve => {
                    rimraf(logPath).then(resolve);
                });
            }
        }
        mkdirSync(logPath);
    }

    function generateLogPath(command: string, args?: readonly string[]) {
        return pathFromRoot(`./logs/${command}-${args?.length}-${new Date().toUTCString()}.log`);
    }

    export async function create(command: string, args?: readonly string[]): Promise<number> {
        return fileDescriptorFromStream(generateLogPath(command, args));
    }
}
export namespace ProcessFactory {
    export type Sink = 'pipe' | 'ipc' | 'ignore' | 'inherit' | Stream | number | null | undefined;

    export async function createWorker(command: string, args?: readonly string[], stdio?: StdioOptions | 'logfile', detached = true): Promise<ChildProcess> {
        if (stdio === 'logfile') {
            const logFd = await Logger.create(command, args);
            // eslint-disable-next-line no-param-reassign
            stdio = ['ignore', logFd, logFd];
        }
        const child = spawn(command, args ?? [], { detached, stdio });
        child.unref();
        return child;
    }
}