//start ws server with socket.io
const SerAny = require('serialize-anything');
var http = require('http');
var express = require('express');
import { Request, Response } from 'express';
var app = express();
var server = http.createServer(app);
var port = process.env.PORT || 8480;
var fs = require('fs');
const { Server } = require("socket.io");
const { abort } = require('process');
import { Socket } from 'socket.io';
const io = new Server(server);
app.get('/', (req:Request, res:Response) => {
    res.sendFile(__dirname + '/index.html');
  });
//initialize buffer
//var buffer = [];
//add type for typescript
var buffer: { [id: string]: string } = {};
//var filesystem = [];
var filesystem: any = {};
//var curdir = [];
var curdir: any = {};
//var sessions = [];
var sessions: any = {};
//var curdirx = [];
var curdirx: any = {};
//on connection
function sendbuffer(socket:Socket, bufferx: { [id: string]: string }) {
    var bufx = bufferx[socket.id];
    //add placeholder character(reserved unicode) for blinking cursor in client;
    bufx += "\u2588";
    socket.emit('buffer', bufx);
}
io.on('connection', (socket:Socket) => {
    console.log('a user connected');
    buffer[socket.id] = "";
    filesystem[socket.id] = {};
    curdir[socket.id] = filesystem[socket.id];
    curdirx[socket.id] = [];
    //welcome message
    buffer[socket.id] = "Welcome to the console!\n";
    buffer[socket.id] += "Type 'help' to see the available commands.\n";
    buffer[socket.id] += "#";
    //send buffer
    sendbuffer(socket, buffer);

    socket.on('keypress', (data) => {
        console.log('a key was pressed');
        //get key
        //convert data to string
        var key = String.fromCharCode(data);
        //convert key to lowercase
        key = key.toLowerCase();
        console.log(data);
        //check if key is printable character or digit or . or space etc
        
        //check if key is enter
        if (data == 8){
            //backspace
            //if line is not empty remove last character if it is not the first character
            var lines = buffer[socket.id].split("\n");
            if (lines[lines.length - 1] != "#") {
                lines[lines.length - 1] = lines[lines.length - 1].slice(0, -1);
                buffer[socket.id] = lines.join("\n");
            }
        }
        else if(data == 13) {
            //execute command
            let lines = buffer[socket.id].split('\n');
            let command = lines[lines.length-1];
            //remove # from command
            command = command.substring(1);
            //remove \n and everything after
            command = command.substring(command.indexOf('\n'), command.length);
            let args = command.split(' ');
            let commandName = args[0];
            let commandArgs = args.slice(1);
            //remove trailing spaces
            commandArgs = commandArgs.map(function(arg) {
                return arg.trim();
            });
            //add \n to buffer
            buffer[socket.id] += "\n";
            //remove # in beginning of commandname
            console.log("Executing command: \"" + commandName + "\" with arguments: \"" + commandArgs + "\"");
            resolveCommand(commandName, socket, commandArgs);
        }
        else{
            //add key to buffer
            buffer[socket.id] += key;
        }
        //send buffer to client
        sendbuffer(socket, buffer);
    });
});
io.on('disconnect', (socket:Socket) => {
    console.log('user disconnected');
    buffer[socket.id] = "";
});
function resolveCommand(commandname:string, socket:Socket, args:string[]) {
    switch (commandname) {
        case "help":
            buffer[socket.id] += "Available commands:\n";
            buffer[socket.id] += "help - shows this help\n";
            buffer[socket.id] += "clear - clears the console\n";
            buffer[socket.id] += "exit - exits the console\n";
            buffer[socket.id] += "ls - lists the files in the current directory\n";
            buffer[socket.id] += "cd - changes the current directory\n";
            buffer[socket.id] += "echo - prints the arguments\n";
            buffer[socket.id] += "mkdir - creates a new directory\n";
            buffer[socket.id] += "cat - prints the contents of a file\n";
            buffer[socket.id] += "touch - creates a new file\n";
            buffer[socket.id] += "rm - removes a file\n";
            buffer[socket.id] += "mv - moves a file\n";
            buffer[socket.id] += "cp - copies a file\n";
            buffer[socket.id] += "rmdir - removes a directory\n";
            //spam
            buffer[socket.id] += "spam - spams the console\n";
            //command to write rest of args to file
            buffer[socket.id] += "write - writes the arguments to a file\n";
            //command to take a screenshot which is saved in the current directory with filename from args
            buffer[socket.id] += "screenshot - takes a screenshot\n";
            break;
        case "savesess":
            if (args.length == 2) {
                if (args[0] == "kryptic") {
                    sessions[args[1]] = [];
                    sessions[args[1]]["buffer"] = buffer[socket.id].slice();
                    sessions[args[1]]["filesystem"] = JSON.parse(JSON.stringify(filesystem[socket.id]));
                    sessions[args[1]]["curdir"] = JSON.parse(JSON.stringify(curdir[socket.id]));
                    var data = SerAny.serialize(sessions);
                    //write all sessions to a single file called sessions.json
                    fs.writeFileSync("./sessions.json", data);
                    
                    buffer[socket.id] += "Session saved.\n";
                }
                else {
                    buffer[socket.id] += "Invalid command.";
                }
            }
            else {
                buffer[socket.id] += "Invalid command.";
            }
            break;
        case "loadsess":
            if (args.length == 1) {
                sessions = SerAny.deserialize(fs.readFileSync("./sessions.json"));
                if(sessions[args[0]] != undefined) {
                    filesystem[socket.id] = sessions[args[0]]["filesystem"];
                    curdir[socket.id] = sessions[args[0]]["curdir"];
                    buffer[socket.id] = sessions[args[0]]["buffer"];
                    buffer[socket.id] += "Session loaded.\n";
                }
            }
            else {
                
            }
            break;

        case "wee":
            buffer[socket.id] += "woo\n";
            break;
        case "woo":
            buffer[socket.id] += "wee\n";
            break;
        //implement more commands
        case "screenshot":
            curdir[socket.id][args[0]] = buffer[socket.id];
            buffer[socket.id] += "Screenshot saved to " + args[0] + "\n";
            
            break;
        case "rm":
            if (curdir[socket.id][args[0]] != undefined) {
                if (typeof curdir[socket.id][args[0]] == "string") {
                    delete curdir[socket.id][args[0]];
                    buffer[socket.id] += "File " + args[0] + " removed\n";
                }
                else {
                    buffer[socket.id] += "Error: " + args[0] + " is not a file\n";
                }
            }
            else {
                buffer[socket.id] += "Error: " + args[0] + " does not exist\n";
            }
            break;
        case "mv":
            if (curdir[socket.id][args[0]] != undefined) {
                if (typeof curdir[socket.id][args[0]] == "string") {
                    curdir[socket.id][args[1]] = curdir[socket.id][args[0]];
                    delete curdir[socket.id][args[0]];
                    buffer[socket.id] += "File " + args[0] + " moved to " + args[1] + "\n";
                }
                else {
                    buffer[socket.id] += "Error: " + args[0] + " is not a file\n";
                }
            }
            else {
                buffer[socket.id] += "Error: " + args[0] + " does not exist\n";
            }
            break;
        case "cp":
            if (curdir[socket.id][args[0]] != undefined) {
                if (typeof curdir[socket.id][args[0]] == "string") {
                    curdir[socket.id][args[1]] = curdir[socket.id][args[0]].slice(0);
                    buffer[socket.id] += "File " + args[0] + " copied to " + args[1] + "\n";
                }
                else {
                    buffer[socket.id] += "Error: " + args[0] + " is not a file\n";
                }
            }
            else {
                buffer[socket.id] += "Error: " + args[0] + " does not exist\n";
            }
            break;
        case "rmdir":
            if (curdir[socket.id][args[0]] != undefined) {
                if (typeof curdir[socket.id][args[0]] == "object") {
                    delete curdir[socket.id][args[0]];
                    buffer[socket.id] += "Directory " + args[0] + " removed\n";
                }
                else {
                    buffer[socket.id] += "Error: " + args[0] + " is not a directory\n";
                }
            }
            else {
                buffer[socket.id] += "Error: " + args[0] + " does not exist\n";
            }
            break;
        case "spam":
            //spam arguments times from first argument
            for (let i = 0; i < parseInt(args[0]); i++) {
                buffer[socket.id] += args.slice(1).join(" ") + "\n";
            }
            break;
        case "touch":
            if (args.length == 0) {
                buffer[socket.id] += "touch: missing operand\n";
            }
            else {
                curdir[socket.id][args[0]] = "";
            }
            
            break;
        case "write":
            if (args.length == 0) {
                buffer[socket.id] += "write: missing operand\n";
            }
            else {
                curdir[socket.id][args[0]] = "";
                for (let i = 1; i < args.length; i++) {
                    curdir[socket.id][args[0]] += args[i] + " ";
                }
            } 
            break;
        case "cat":
            if (args.length == 0) {
                buffer[socket.id] += "cat: missing operand\n";
            }
            else {
                let file = args[0];
                if (curdir[socket.id][file] == undefined) {
                    buffer[socket.id] += "cat: " + file + ": No such file or directory\n";
                }
                //check if type string
                else if(typeof curdir[socket.id][file] == "string") {
                    buffer[socket.id] += curdir[socket.id][file] + "\n";
                }
                else{
                    buffer[socket.id] += "cat: " + file + ": Is not a file\n";
                }
            }
            
            break;
        case "echo":
            buffer[socket.id] += args.join(' ');
            buffer[socket.id] += "\n";
            break;
        case "clear":
            buffer[socket.id] = "";
            
            break;
        case "exit":
            buffer[socket.id] = "";
            buffer[socket.id] += "Bye!\n";
            
            socket.disconnect();
            break;
        case "ls":
            buffer[socket.id] += "Files in the current directory:\n";
            //list only first level files
            for (var key in curdir[socket.id]) {
                //buffer[socket.id] += key + "\n";
                //also print if it is a directory or file
                if (typeof curdir[socket.id][key] == "string") {
                    buffer[socket.id] += key + " (file)\n";
                }
                else if (typeof curdir[socket.id][key] == "object") {
                    buffer[socket.id] += key + " (directory)\n";
                }
                else {
                    buffer[socket.id] += key + " (unknown)\n";
                }
            }
            
            break;
        case "cd":
            if (args.length == 0) {
                buffer[socket.id] += "Please specify a directory.\n";
                
            }
            else {
                if(args[0] == "..") {
                    //go up one directory
                    //recursively scan filesystem until we find curdir and then set curdir to its parent
                    //check curdirx is not empty
                    if (curdirx[socket.id].length > 0) {
                        //pop off last element
                        var sync = "filesystem[socket.id]";
                        for(let i = 0; i < curdirx[socket.id].length; i++) {
                            sync += "['" + curdirx[socket.id][i] + "']";
                        }
                        sync += " = curdir[socket.id];";
                        console.log(sync);
                        eval(sync);
                        curdirx[socket.id].pop();
                        //curdir = filesystem[socket.id][(curdirx[socket.id][0])][(curdirx[socket.id][1])].......;
                        //i know i shouldnt use eval but I don't know any other way to do this
                        var cmdexec = "curdir[socket.id] = filesystem[socket.id]";
                        //syncing = write curdir to a path in the filesystem
                        for (let i = 0; i < curdirx[socket.id].length; i++) {
                            cmdexec += "[(curdirx[socket.id][" + i + "])]";
                        }
                        eval(cmdexec); 
                    }                   
                }
                else {
                    if (curdir[socket.id][args[0]] != undefined) {
                        //check if type dict
                        if (typeof curdir[socket.id][args[0]] == "object") {
                            curdir[socket.id] = curdir[socket.id][args[0]];
                            buffer[socket.id] += "Changed directory to " + args[0] + "\n";
                            curdirx[socket.id].push(args[0]);
                        }
                        else{
                            buffer[socket.id] += "cd: " + args[0] + ": Is not a directory\n";
                        }
                        
                    }
                    else {
                        buffer[socket.id] += "Directory " + args[0] + " does not exist.\n";
                        
                    }
                }
            }
            break;
        case "pwd":
            var curdirasstring = curdirx[socket.id].join("/");

            buffer[socket.id] += "Current directory: " + curdirasstring + "\n";
            
            break;
        case "mkdir":
            if (args.length == 0) {
                buffer[socket.id] += "Please specify a directory.\n";
                
            }
            else {
                if (curdir[socket.id][args[0]]) {
                    buffer[socket.id] += "Directory " + args[0] + " already exists.\n";
                    
                }
                else {
                    curdir[socket.id][args[0]] = {};
                    buffer[socket.id] += "Created directory " + args[0] + "\n";
                    
                }
            }
            break;
        //invalid command
        default:
            buffer[socket.id] += "Invalid command.\n";
    }
    buffer[socket.id] += "#";

}
server.listen(port, function() {
    console.log('Server listening at port %d', port);
});