import { spawn } from "child_process";
import dotenv from 'dotenv';
dotenv.config()

/**
 * Object to store references to spawned processes.
 * @type {Object.<string, import('child_process').ChildProcess>}
 */
const runningProcesses = {};

/**
 * Launches a new process if it's not already running.
 * @param {string} processName - The name of the process to launch.
 * @param {string[]} args - The arguments to pass to the process.
 * @param {boolean} waitForClose - Set this to wait to return until the process exits
 * @param {boolean} returnOutput - Set this in addition to 'waitForClose' to return the script output when the process closes
 * @param {boolean} waitForClose - Set the current working directory of the process being launched
 */
export const launchProcess = (processName, args, waitForClose = false, returnOutput = false, pcwd = undefined) => {
    if (!runningProcesses[processName]) {
        let childProcess;
        if (pcwd) {
            childProcess = spawn(processName, args, { cwd: pcwd });
        }
        else {
            childProcess = spawn(processName, args);
        }

        // Store reference to the spawned process
        runningProcesses[processName] = childProcess;

        // Output the process output in development
        var scriptOutput = "";

        // Get the stdout from the child process
        childProcess.stdout.setEncoding('utf8');
        childProcess.stdout.on('data', (data) => {
            if (process.env.NODE_ENV === "development") console.log(`Data from ${processName}:`, data);
            scriptOutput += data.toString();
        });

        // Get the stderr from the child process
        childProcess.stderr.setEncoding('utf8');
        childProcess.stderr.on('data', (data) => {
            if (process.env.NODE_ENV === "development") console.log(`Data from ${processName}:`, data);
            scriptOutput += data.toString();
        })

        let output = new Promise(res => {
            childProcess.on('exit', (code, signal) => {
                // Remove reference to the process when it exits
                delete runningProcesses[processName];
                console.log(`${processName} process exited with code ${code} and signal ${signal}`);
                console.log("Child process console output: ", scriptOutput);
                // Return the full script output if requested
                if (returnOutput === true) {
                    return res(scriptOutput)
                }
                return res(code);
            })
        });

        if (waitForClose === true) {
            return output
        }

        console.log(`${processName} process started.`);
    } else {
        console.log(`${processName} process is already running.`);
    }
}

/**
 * Checks the status of a process.
 * @param {string} processName - The name of the process to check.
 * @returns {string} A message indicating whether the process is running or not.
 */
export const checkProcessStatus = (processName) => {
    const childProcess = runningProcesses[processName];
    if (childProcess) {
        // Check if the process is running
        if (!childProcess.killed) {
            return `${processName} process is running.`;
        } else {
            return `${processName} process is not running.`;
        }
    } else {
        return `${processName} process is not running.`;
    }
}

/**
 * Kills a running process.
 * @param {string} processName - The name of the process to kill.
 */
export const killProcess = (processName) => {
    const childProcess = runningProcesses[processName];
    if (childProcess) {
        childProcess.kill();
        console.log(`${processName} process killed.`);
    } else {
        console.log(`${processName} process is not running.`);
    }
}

export const getRunningProcesses = () => runningProcesses;