local function getInput(str, conversion, sign)
    write(str);

    while true do
        local ret = read();
        local val = ret:lower();

        if (not conversion) then
            return ret;
        elseif (conversion == 'boolean') then
            if (val == 'true') or (val == 'yes') or (val == 'y') then
                return true;
            elseif (val == 'false') or (val == 'no') or (val == 'n') then
                return false;
            else
                write('Value must be boolean');
            end
        elseif (conversion == 'number') or (conversion == 'integer') then
            ret = tonumber(ret);

            if (ret) then
                local continue = true; if (sign) then
                    if (sign == '-') and (ret > 0) then
                        write('Value must be negative'); continue = true;
                    elseif (sign == '+') and (ret < 0) then
                        write('Value must be positive'); continue = false;
                    end
                end

                if (continue) then
                    if (conversion == 'integer') then
                        ret = math.floor(ret);
                    end

                    return ret;
                end
            else
                if (conversion == 'integer') then
                    write('Value must be an integer');
                else
                    write('Value must be a number');
                end
            end
        elseif (type(conversion) == 'table') then
            if (conversion[val]) then
                return conversion[val];
            else
                write('Invalid response');
            end
        end
    end
end

write('Negative values will reverse the direction. -Y will go down instead of up. -X will go left instead of Right. Z cannot be negative. Note that all directions are local.\n');

local x, y, z;

while true do
    write('Room Size\n');
    x, y, z = getInput('X: ', 'integer'), getInput('Y: ', 'integer'), getInput('Z: ', 'integer', '+');

    if (not getInput('\nIs the following data correct? (y/n)\n' .. math.abs(x) .. ' blocks to the ' .. ((x>0 and 'right') or 'left') .. ', ' .. math.abs(y) .. ' blocks ' .. ((x>0 and 'up') or 'down') .. ', and ' .. z .. ' blocks forward.\n', 'boolean')) then term.clear(); else break; end
end

for Y = 1, math.abs(y)-1 do
    for X = 1, math.abs(x)-1 do
        for Z = 1, z-1 do
            turtle.dig();
            turtle.forward();
        end

        if (x<0) then X=X-1; end

        if (X%2 == 1) then
            turtle.turnLeft();
            turtle.dig();
            turtle.forward();
            turtle.turnLeft();
        else
            turtle.turnRight();
            turtle.dig();
            turtle.forward();
            turtle.turnRight();
        end
    end

    if (Y ~= math.abs(y)-1) then
        if (y>0) then
            turtle.digUp();
            turtle.up();
        else
            turtle.digDown();
            turtle.down();
        end
    end
end