Fully awesome calculator in vanilla Minecraft using MoonCraft

_calculator.lua

import("chat")
import("math")
import("debug")
import("./calculator.js")

command("gamerule sendCommandFeedback false")
command("scoreboard objectives add calc dummy")
command("scoreboard objectives add calcVal dummy")

curr = score("@e[type=ArmorStand,x=0,y=5,z=-1,r=0]", "calc")
currVal = score("@e[type=ArmorStand,x=0,y=5,z=-1,r=0]", "calcVal")

containsBrackets = false
containsSpecial = false
containsPow = false
containsMultiplication = false
containsAddition = false

function readInput()
    local input = -1
    repeat

        applyNames() -- do this at first for output

        input = -1
        showCalc(input)

        repeat
            --wait
        until input > 0

        if input == codeOf("(") or input == codeOf(")") then
            containsBrackets = true
        elseif input == codeOf("sqrt") or input == codeOf("sin") or input == codeOf("cos") then
            containsSpecial = true
        elseif input == codeOf("^") then
            containsPow = true
        elseif input == codeOf("*") or input == codeOf("/") then
            containsMultiplication = true
        elseif input == codeOf("+") or input == codeOf("-") then
            containsAddition = true
        end

        if input == codeOf("=") then
            --nothing
        elseif input == codeOf("DEL") then
            killCurrent()
            moveRight()
        elseif input == codeOf("AC") then
            command("kill @e[type=ArmorStand,score_calc_min=1]")
        else
            moveLeft()
            command("summon ArmorStand 0 5 -1 {CustomName:\"calc_input\",NoGravity:true,CustomNameVisible:true}")
            curr = input
        end

    until input == codeOf("=")
end

function resetInput()
    while "/testfor @e[type=ArmorStand,x=1,y=5,z=-1,r=0]" do
        moveRight()
    end
end

function parseNums()
    while "/testfor @e[type=ArmorStand,x=0,y=5,z=-1,r=0]" do

        if curr > 0 and curr < 11 then

            local val = 0.0
            repeat
                val = val * 10 + curr % 10
                killCurrent()
                catchFromRight()
            until not (curr > 0 and curr < 11)

            if curr == codeOf(".") then
                killCurrent()
                catchFromRight()

                local pos = 10
                repeat
                    val = val + float(curr % 10) / pos
                    pos = pos * 10

                    killCurrent()
                    catchFromRight()
                until not (curr > 0 and curr < 11)
            end

            extendToRight()
            command("summon ArmorStand 0 5 -1 {CustomName:\"Number\",NoGravity:true,CustomNameVisible:true}")
            curr = codeOf("__num")
            currVal = floatBase(val)

        elseif curr == codeOf("pi") then
            curr = codeOf("__num")
            currVal = floatBase(PI)
        elseif curr == codeOf("e") then
            curr = codeOf("__num")
            currVal = floatBase(EULER)
        elseif curr == codeOf("rnd") then
            curr = codeOf("__num")
            currVal = random() * 100
        end

        moveLeft()
    end
end

function parseBrackets()
    while "/testfor @e[type=ArmorStand,x=0,y=5,z=-1,r=0]" do
        if curr == codeOf("(") then
            killCurrent()
            local indent = 1
            repeat
                moveLeft()
                if curr == codeOf("(") then
                    indent = indent + 1
                elseif curr == codeOf(")") then
                    indent = indent - 1
                end
            until indent == 0 or not "/testfor @e[type=ArmorStand,x=0,y=5,z=-1,r=0]"

            killCurrent()
            resetInput()
            parseCurrent()

            moveLeft()
            catchFromRight()
            moveRight()
            moveRight()
            catchFromLeft()
        end
        moveLeft()
    end
end

function parseSpecial() -- sin cos sqrt
    while "/testfor @e[type=ArmorStand,x=0,y=5,z=-1,r=0]" do
        local result = 0.0

        if curr == codeOf("sqrt") then
            killCurrent()
            catchFromRight()

            result = sqrt(floatFromBase(currVal))
            currVal = floatBase(result)
        elseif curr == codeOf("sin") then
            killCurrent()
            catchFromRight()

            result = sin(floatFromBase(currVal))
            currVal = floatBase(result)
        elseif curr == codeOf("cos") then
            killCurrent()
            catchFromRight()

            result = cos(floatFromBase(currVal))
            currVal = floatBase(result)
        end

        moveLeft()
    end
end

function parsePow()
    while "/testfor @e[type=ArmorStand,x=0,y=5,z=-1,r=0]" do
        if curr == codeOf("^") then
            moveRight()

            local left = floatFromBase(currVal)
            killCurrent()
            catchFromRight()

            killCurrent()
            catchFromRight()

            local right = int(floatFromBase(currVal))

            currVal = pow(left, right) * 100
        end

        moveLeft()
    end
end

function parseMultiplication() -- * /
    while "/testfor @e[type=ArmorStand,x=0,y=5,z=-1,r=0]" do
        if curr == codeOf("*") or curr == codeOf("/") then
            moveRight()

            local left = floatFromBase(currVal)
            killCurrent()
            catchFromRight()

            local op = int(curr)
            killCurrent()
            catchFromRight()

            local right = floatFromBase(currVal)

            if op == codeOf("*") then
                currVal = floatBase(left * right)
            elseif op == codeOf("/") then
                currVal = floatBase(left / right)
            end
        end

        moveLeft()
    end
end

function parseAddition() -- + -
    while "/testfor @e[type=ArmorStand,x=0,y=5,z=-1,r=0]" do
        if curr == codeOf("+") or curr == codeOf("-") then
            moveRight()

            local left = floatFromBase(currVal)
            killCurrent()
            catchFromRight()

            local op = int(curr)
            killCurrent()
            catchFromRight()

            local right = floatFromBase(currVal)

            if op == codeOf("+") then
                currVal = floatBase(left + right)
            elseif op == codeOf("-") then
                currVal = floatBase(left - right)
            end
        end

        moveLeft()
    end
end



function parseCurrent()
    if containsBrackets then
        parseBrackets()
        resetInput()
    end

    if containsSpecial then
        parseSpecial()
        resetInput()
    end

    if containsPow then
        parsePow()
        resetInput()
    end

    if containsMultiplication then
        parseMultiplication()
        resetInput()
    end

    if containsAddition then
        parseAddition()
        resetInput()
    end
end


while true do
    containsBrackets = false
    containsSpecial = false
    containsPow = false
    containsMultiplication = false
    containsAddition = false

    readInput()
    resetInput()

    parseNums()
    resetInput()

    parseCurrent()

    local result = floatFromBase(currVal)
    local negative = false

    if result < 0 then
        negative = true
        result = result * -1
    end

    local left = int(result)
    local right = floatBase(result) - left * 100
    command("kill @e[type=ArmorStand,score_calc_min=1]")

    if right ~= 0 then

        local digit = right % 10
        right = right / 10

        if digit ~= 0 then
            moveRight()
            command("summon ArmorStand 0 5 -1 {CustomName:\"calc_output\",NoGravity:true,CustomNameVisible:true}")
            curr = digit
        end

        digit = right % 10
        if digit == 0 then
            digit = codeOf("0")
        end
        moveRight()
        command("summon ArmorStand 0 5 -1 {CustomName:\"calc_output\",NoGravity:true,CustomNameVisible:true}")
        curr = digit

        if false then --wait one tick so current snapshot doesnt fck off armorstand positions for the client
        end

        moveRight()
        command("summon ArmorStand 0 5 -1 {CustomName:\"calc_output\",NoGravity:true,CustomNameVisible:true}")
        curr = codeOf(".")
    end

    if left > 0 then
        repeat
            local digit = left % 10
            left = left / 10

            if digit == 0 then
                digit = codeOf("0")
            end

            moveRight()
            command("summon ArmorStand 0 5 -1 {CustomName:\"calc_output\",NoGravity:true,CustomNameVisible:true}")
            curr = digit
        until left == 0
    else
        moveRight()
        command("summon ArmorStand 0 5 -1 {CustomName:\"calc_output\",NoGravity:true,CustomNameVisible:true}")
        curr = codeOf("0")
    end

    if negative then
        moveRight()
        command("summon ArmorStand 0 5 -1 {CustomName:\"calc_output\",NoGravity:true,CustomNameVisible:true}")
        curr = codeOf("-")

        if false then --wait one tick so current snapshot doesnt fck off armorstand positions for the client
        end

        moveRight()
        command("summon ArmorStand 0 5 -1 {CustomName:\"calc_output\",NoGravity:true,CustomNameVisible:true}")
        curr = codeOf("0")
    end

    while "/testfor @e[type=ArmorStand,x=-1,y=5,z=-1,r=0]" do
        moveLeft()
    end
end

calculator.js

var tellraw = scope.get("tellraw");
var chat_message = scope.get("chat_message");
var chat_event = scope.get("chat_event");
var scoreName = scope.get("OBJECTIVE_NAME");
var float = scope.get("float");

var layout = [
    "%input%",
    "",
    "sqrt sin cos ( )",
    "7 8 9 DEL AC",
    "4 5 6  * / pi",
    "1 2 3  + - e",
    "0   .   ^ = rnd"
];

var nextCode = 11;
var codes = {};
for(var i = 0; i < layout.length; i++)
{
    var line = layout[i].split(" ");
    var chatObjs = [];

    for(var ii = 0; ii < line.length; ii++)
    {
        var button = line[ii];
        if(/[0-9]/g.test(button))
        {
            codes[button] = parseInt(button) || 10;
            continue;
        }

        codes[button] = nextCode;
        nextCode++;
    }
}
codes["__num"] = nextCode;
nextCode++;

exports.showCalc = function(val)
{
    tellraw((new Array(20 - layout.length + 1)).join("\n"));

    for(var i = 0; i < layout.length; i++)
    {
        var line = layout[i].split(" ");
        var chatObjs = [""];

        if(line.length == 1 && line[0] == "%input%")
        {
            for(var ii = 20; ii > -1; ii--)
            {
                var sel = "@e[type=ArmorStand,x={0},y=5,z=-1,r=0]".format(ii);
                chatObjs.push({selector: sel});
            }

            tellraw.apply(undefined, chatObjs);
            continue;
        }

        for(var ii = 0; ii < line.length; ii++)
        {
            var button = line[ii];

            if(button.trim() == "")
            {
                chatObjs.push(" ");
                continue;
            }

            var color = "white";
            if(["DEL", "AC", "="].indexOf(button) != -1)
                color = "red";
            else if(/[0-9]/.test(button))
                color = "yellow";
            else if(["pi", "e", "rnd"].indexOf(button) != -1)
                color = "green";

            var ev = chat_event("run_command", "/scoreboard players set {0} {1} {2}".format(val.name, scoreName, codes[button]));
            var msg = chat_message(button, color, false, ev);
            chatObjs.push(msg);
            chatObjs.push(" ");
        }

        tellraw.apply(undefined, chatObjs);
    }
};

exports.applyNames = function()
{
    for(var key in codes)
    {
        var _key = /[0-9a-zA-Z\.\(\)]/g.test(key) ? key : " " + key + " ";
        command("entitydata @e[score_calc_min={0},score_calc={0}] {CustomName:\"{1}\"}".format(codes[key], _key))
    }
}

exports.codeOf = function(button)
{
    if(!codes.hasOwnProperty(button))
        throw "There is no button with the label " + button;
    return codes[button];
}

exports.floatBase = function(val)
{
    return val.base;
}

exports.floatFromBase = function(base)
{
    var val = float();
    val.base.set(base);
    return val;
}

exports.killCurrent = function()
{
    command("kill @e[type=ArmorStand,x=0,y=5,z=-1,r=0]");
}

exports.moveLeft = function(amount)
{
    command("tp @e[type=ArmorStand,score_calc_min=1] ~1 ~ ~");
}

exports.moveRight = function()
{
    command("tp @e[type=ArmorStand,score_calc_min=1] ~-1 ~ ~");
}

exports.catchFromRight = function()
{
    command("tp @e[type=ArmorStand,x=0,y=5,z=-1,dx=-100] ~1 ~ ~");
}
exports.extendToRight = function()
{
    command("tp @e[type=ArmorStand,x=0,y=5,z=-1,dx=-100] ~-1 ~ ~");
}

exports.catchFromLeft = function()
{
    command("tp @e[type=ArmorStand,x=0,y=5,z=-1,dx=100] ~-1 ~ ~");
}
exports.extendToLeft = function()
{
    command("tp @e[type=ArmorStand,x=0,y=5,z=-1,dx=100] ~1 ~ ~");
}