/*
You are attempting to solve a Coding Contract. You have 10 tries remaining, after which the contract will self-destruct.

Given the following string containing only digits, return an array with all possible valid IP address combinations that can be created from the string:

Note that an octet cannot begin with a '0' unless the number itself is exactly '0'. For example, '192.168.010.1' is not a valid IP.

Examples:

25525511135 -> ["255.255.11.135", "255.255.111.35"]
1938718066 -> ["193.87.180.66"]
*/

/** @param {NS} ns */
function isValidIP(ip) {
    var octets = ip.split(".");
    if(octets.length != 4) return false;

    for(var i = 0; i < octets.length; i++) {
        var length = octets[i].length;
        var value = parseInt(octets[i]);
        if(length == 0 || length > 3 || octets[i].charAt(0) == '0' || value > 255 || value < 0) {
            return false;
        }
    }

    return true;
}

/** @param {NS} ns */
function isValidOctet(octet) {
    if(octet.length <= 0 || octet.length > 3) return false;
    
    var octetValue = parseInt(octet);
    if(octetValue > 255 || octetValue < 0) return false;

    return true;
}

function generateOctet(ips, octets, input, sliceRange) {
    var octets1 = [...octets, input.slice(0, sliceRange)];
    if(isValidOctet(octets1[octets1.length - 1])) {
        generateIPAddress(ips, octets1, input.slice(sliceRange, input.length));
    }
}

function generateIPAddress(ips, octets, input) {
    if(input.length == 0) {
        var ip = octets.join(".");
        if(isValidIP(ip)) {
            if(ips.indexOf(ip) == -1) {
                ips.push(ip);
                return ips;
            }
        }
    } else {
        generateOctet(ips, octets, input, 3);
        generateOctet(ips, octets, input, 2);
        generateOctet(ips, octets, input, 1);
    }

    return ips;
}

/** @param {NS} ns */
function test(ns, ips, expected) {
    if(ips.length != expected.length) {
        ns.tprint("test: generated and expected lengths differ!");
        return false;
    }

    for(var i = 0; i < ips.length; i++) {
        if(ips[i] != expected[i]) {
            ns.tprint(ips[i] + " != " + expected[i]);
            ns.tprint("test: values differ!");
            return false;
        }
    }

    return true;
}

/** @param {NS} ns */
function testClient(ns) {
    var testInput1 = "25525511135";
    var testExpected1 = ["255.255.11.135", "255.255.111.35"];
    var testInput2 = "1938718066";
    var testExpected2 = ["193.87.180.66"];
    var testResult1 = generateIPAddress(ns, [], [], testInput1);
    var testResult2 = generateIPAddress(ns, [], [], testInput2);

    ns.tprint("Result 1: " + testResult1);
    ns.tprint("Result 2: " + testResult2);

    ns.tprint(test(ns, testResult1.reverse(), testExpected1));
    ns.tprint(test(ns, testResult2.reverse(), testExpected2));
}

export function generateIPAddresses(input) {
    return generateIPAddress([], [], input.toString())
}

/** @param {NS} ns */
export async function main(ns) {
    if(ns.args.length > 0) {
        var arg = ns.args[0];
        if(arg == "--test" || arg == "-t") {
            testClient(ns);
        } else if(ns.args.length == 2 && (arg == "--print" || arg == "-p")) {
            var input = ns.args[1].toString();
            ns.tprint(generateIPAddress([], [], input));
        } else {
            var input = arg.toString();
            return generateIPAddress([], [], input)
        }
    } else {
        ns.tprint("Usage error: Require an input to generate IP addresses or the --test|-t flag.");
    }
}