let currentState = {
    "username": "guest",
    "directory": "/"
}

const fileSystem = require("../filesystem.json")

function getCurrentDir(){
    return currentState.directory;
}

function customTextResponse(res, txt){
    respondToCommand(res, txt, currentState.directory, "");
}


function ls(res) {
    const command = "ls";
    const contents = fileSystem[currentState.directory];

    if (contents && typeof contents === 'object') {
        let keys = Object.keys(contents)
        respondToCommand(res, keys.join("  "), currentState.directory, command);
    } else {
        respondToCommand(res, "No Files Found In Current Directory", currentState.directory, command);
    }
}

function whoami(res){
    const command = "whoami"
    respondToCommand(res, currentState.username, currentState.directory, command);
}

function cd (res, raw_command) {
    const command = "cd";
    let arguement = raw_command.split(" ")[1]

    //check if folder to cd to is in current dir
    const contents = fileSystem[currentState.directory];

    if (contents && typeof contents==="object"){
        let keys = Object.keys(contents);
        for (let i = 0; i < keys.length; i++){
            let key = keys[i]

            if (key == arguement && fileSystem[currentState.directory][key] == "dir"){
                currentState.directory = currentState.directory + arguement;

                if (!currentState.directory.endsWith("/")) currentState.directory += "/";
                respondToCommand(res, "", currentState.directory, command);
                return;
            }
            else if (key == arguement){
                respondToCommand(res, "You cannot open a file as a directory", currentState.directory, command);
                return;
            }
        }

        // check a few things:
        if (arguement == "/" || arguement == "~" || arguement == "~/"){
            currentState.directory = "/";
            respondToCommand(res, "", currentState.directory, command);
            return;
        }

        if (arguement == ".." || arguement == "../"){
            //move 1 folder back
            const lastSlashIndex = currentState.directory.lastIndexOf('/');
            const pathWithoutTrailingSlash = lastSlashIndex === currentState.directory.length - 1 ? currentState.directory.substring(0, currentState.directory.length - 1) : currentState.directory;
            const secondLastSlashIndex = pathWithoutTrailingSlash.lastIndexOf('/');
            currentState.directory = pathWithoutTrailingSlash.substring(0, secondLastSlashIndex + 1);

            respondToCommand(res, "", currentState.directory, command);
            return;
        }

        respondToCommand(res, "Unable to open directory", currentState.directory, command);
    }
    else 
    {
        respondToCommand(res, "Internal Server Error, try again later.", currentState.directory, command)
    }
}

function pwd (res){
    const command = "pwd";
    respondToCommand(res, currentState.directory, currentState.directory, command);
}

function cat (res, raw_command){
    const command = "cat";
    let arguement = raw_command.split(" ")[1]

    //check if folder to cd to is in current dir
    const contents = fileSystem[currentState.directory];

    if (contents && typeof contents==="object"){
        let keys = Object.keys(contents);
        for (let i = 0; i < keys.length; i++){
            let key = keys[i]

            if (key == arguement && fileSystem[currentState.directory][key] != "dir"){
                respondToCommand(res, fileSystem[currentState.directory][key], currentState.directory, command);
                return;
            }
            else if (key == arguement){
                respondToCommand(res, "You cannot open a directory as a file", currentState.directory, command);
                return;
            }
        }
        respondToCommand(res, "Unable to open file", currentState.directory, command)
    }
    else 
    {
        respondToCommand(res, "Internal Server Error, try again later.", currentState.directory, command)
    }

}



function help(res){
    const command = "help"
    const text = `
    Welcome to the fancy help menu!!<br>
    Here is a list of the available commands:<br><br>

    "help" - shows you this menu<br>
    "ls" - shows you the files and directories in your current directory<br>
    "cd" - move into a folder you specify, you can use the name of the folder, or you can also use things like ../ to move back one folder<br>
    "whoami" - shows you as what user you are logged in as<br>
    "pwd" - shows you the current directory you are currently working in<br>
    "cat" - shows you the content of files, fox example cat file.txt shows you the content of file.txt if it is in the current directory<br>
    `
    respondToCommand(res, text, currentState.directory, command);
}

module.exports = {
    getCurrentDir,
    customTextResponse,

    ls,
    whoami,
    cd,
    pwd,
    cat,
    help,
}



function respondToCommand(res, text, directory, command){
    res.json({
        "username": "guest",
        "directory": directory,
        "response": text,
        "command": command
    })
}