C# custom Console.ReadLine with hidden characters

HiddenConsoleReadLine.cs

using System;
using Towel;

namespace ConsoleApp1
{
    class Program
    {
        static void Main()
        {
            Console.WriteLine(
                "This is an example of a custom \"Console.ReadLine\" with masked characters " +
                "for use cases such as passwords. Type \"exit\" to close the program. It supports" +
                "Backspace, Delete, Left/Right Arrows, Escape, Home, and End keypresses and the CTRL modifier.");
            while (true)
            {
                Console.Write("Input: ");
                string input = ConsoleHelper.HiddenReadLine();
                Console.WriteLine(input);
                if (input.ToLower() == "exit")
                {
                    break;
                }
            }
        }
    }
}

namespace Towel
{
    using System.Collections.Generic;

    public static class ConsoleHelper
    {
        public static string HiddenReadLine(char shownCharacter = '*')
        {
            List<char> list = new List<char>();
            HiddenReadLineBase(
                shownCharacter: shownCharacter,
                GetLength: () => list.Count,
                Append: list.Add,
                InsertAt: list.Insert,
                RemoveAt: list.RemoveAt,
                RemoveRange: list.RemoveRange,
                Clear: list.Clear);
            return string.Concat(list);
        }

        internal static void HiddenReadLineBase(
            char shownCharacter,
            Func<int> GetLength,
            Action<char> Append,
            Action<int, char> InsertAt,
            Action<int> RemoveAt,
            Action<int, int> RemoveRange = null,
            Action Clear = null)
        {
            int position = 0;

            RemoveRange ??= (index, length) =>
            {
                for (int i = 0; i < length; i++)
                {
                    RemoveAt(index);
                }
            };

            Clear ??= () => RemoveRange(0, GetLength());

            static void MoveNegative(int count)
            {
                int bufferWidth = Console.BufferWidth;
                int left = Console.CursorLeft;
                int top = Console.CursorTop;
                for (int i = 0; i < count; i++)
                {
                    if (left > 0)
                    {
                        left--;
                    }
                    else
                    {
                        top--;
                        left = bufferWidth - 1;
                    }
                }
                Console.CursorLeft = left;
                Console.CursorTop = top;
            }

            static void MovePositive(int count)
            {
                int bufferWidth = Console.BufferWidth;
                int left = Console.CursorLeft;
                int top = Console.CursorTop;
                for (int i = 0; i < count; i++)
                {
                    if (left == bufferWidth - 1)
                    {
                        top++;
                        left = 0;
                    }
                    else
                    {
                        left++;
                    }
                }
                Console.CursorLeft = left;
                Console.CursorTop = top;
            }

            void MoveToOrigin() => MoveNegative(position);

            void MoveToTail() => MovePositive(GetLength() - position);

            static void ConsoleWriteChar(char @char)
            {
                int temp = Console.CursorLeft;
                Console.Write(@char);
                if (Console.CursorLeft == temp)
                {
                    MovePositive(1);
                }
            }

            static void ConsoleWriteString(string @string)
            {
                foreach (char c in @string)
                {
                    ConsoleWriteChar(c);
                }
            }

            while (true)
            {
                ConsoleKeyInfo keyInfo = Console.ReadKey(true);
                if (keyInfo.Key is ConsoleKey.Enter)
                {
                    if (!keyInfo.Modifiers.HasFlag(ConsoleModifiers.Control) &&
                        !keyInfo.Modifiers.HasFlag(ConsoleModifiers.Shift) &&
                        !keyInfo.Modifiers.HasFlag(ConsoleModifiers.Alt))
                    {
                        MovePositive(GetLength() - position);
                        Console.WriteLine();
                        break;
                    }
                }
                else if (keyInfo.Key is ConsoleKey.Backspace)
                {
                    if (keyInfo.Modifiers.HasFlag(ConsoleModifiers.Control))
                    {
                        MoveToOrigin();
                        ConsoleWriteString(new string(shownCharacter, GetLength() - position) + new string(' ', position));
                        MoveNegative(GetLength());
                        RemoveRange(0, position);
                        position = 0;
                    }
                    else if (position > 0)
                    {
                        if (position == GetLength())
                        {
                            MoveNegative(1);
                            ConsoleWriteChar(' ');
                            MoveNegative(1);
                        }
                        else
                        {
                            MoveToTail();
                            MoveNegative(1);
                            ConsoleWriteChar(' ');
                            MoveNegative(GetLength() - position + 1);
                        }
                        RemoveAt(position - 1);
                        position--;
                    }
                }
                else if (keyInfo.Key is ConsoleKey.Delete)
                {
                    if (!keyInfo.Modifiers.HasFlag(ConsoleModifiers.Control) &&
                        !keyInfo.Modifiers.HasFlag(ConsoleModifiers.Shift) &&
                        !keyInfo.Modifiers.HasFlag(ConsoleModifiers.Alt))
                    {
                        if (position < GetLength())
                        {
                            int left = Console.CursorLeft;
                            int top = Console.CursorTop;
                            MoveToTail();
                            MoveNegative(1);
                            ConsoleWriteChar(' ');
                            Console.CursorLeft = left;
                            Console.CursorTop = top;
                            RemoveAt(position);
                            continue;
                        }
                    }
                }
                else if (keyInfo.Key is ConsoleKey.Escape)
                {
                    if (!keyInfo.Modifiers.HasFlag(ConsoleModifiers.Control) &&
                        !keyInfo.Modifiers.HasFlag(ConsoleModifiers.Shift) &&
                        !keyInfo.Modifiers.HasFlag(ConsoleModifiers.Alt))
                    {
                        MoveToOrigin();
                        int left = Console.CursorLeft;
                        int top = Console.CursorTop;
                        ConsoleWriteString(new string(' ', GetLength()));
                        Console.CursorLeft = left;
                        Console.CursorTop = top;
                        Clear();
                        position = 0;
                    }
                }
                else if (keyInfo.Key is ConsoleKey.Home)
                {
                    if (!keyInfo.Modifiers.HasFlag(ConsoleModifiers.Shift) &&
                        !keyInfo.Modifiers.HasFlag(ConsoleModifiers.Alt))
                    {
                        if (keyInfo.Modifiers.HasFlag(ConsoleModifiers.Control))
                        {
                            MoveToOrigin();
                            ConsoleWriteString(new string(shownCharacter, GetLength() - position) + new string(' ', position));
                            MoveNegative(GetLength());
                            RemoveRange(0, position);
                            position = 0;
                        }
                        else
                        {
                            MoveToOrigin();
                            position = 0;
                        }
                    }
                }
                else if (keyInfo.Key is ConsoleKey.End)
                {
                    if (!keyInfo.Modifiers.HasFlag(ConsoleModifiers.Shift) &&
                        !keyInfo.Modifiers.HasFlag(ConsoleModifiers.Alt))
                    {
                        if (keyInfo.Modifiers.HasFlag(ConsoleModifiers.Control))
                        {
                            MoveToOrigin();
                            ConsoleWriteString(new string(shownCharacter, position) + new string(' ', GetLength() - position));
                            MoveNegative(GetLength() - position);
                            RemoveRange(position, GetLength() - position);
                        }
                        else
                        {
                            MoveToTail();
                            position = GetLength();
                        }
                    }
                }
                else if (keyInfo.Key is ConsoleKey.LeftArrow)
                {
                    if (!keyInfo.Modifiers.HasFlag(ConsoleModifiers.Shift) &&
                        !keyInfo.Modifiers.HasFlag(ConsoleModifiers.Alt))
                    {
                        if (keyInfo.Modifiers.HasFlag(ConsoleModifiers.Control))
                        {
                            MoveToOrigin();
                            position = 0;
                        }
                        else
                        {
                            if (position > 0)
                            {
                                MoveNegative(1);
                                position--;
                            }
                        }
                    }
                }
                else if (keyInfo.Key is ConsoleKey.RightArrow)
                {
                    if (!keyInfo.Modifiers.HasFlag(ConsoleModifiers.Shift) &&
                        !keyInfo.Modifiers.HasFlag(ConsoleModifiers.Alt))
                    {
                        if (keyInfo.Modifiers.HasFlag(ConsoleModifiers.Control))
                        {
                            MoveToTail();
                            position = GetLength();
                        }
                        else
                        {
                            if (position < GetLength())
                            {
                                MovePositive(1);
                                position++;
                            }
                        }
                    }
                }
                else
                {
                    if (!(keyInfo.KeyChar is '\0'))
                    {
                        if (position == GetLength())
                        {
                            ConsoleWriteChar(shownCharacter);
                            Append(keyInfo.KeyChar);
                            position++;
                        }
                        else
                        {
                            int left = Console.CursorLeft;
                            int top = Console.CursorTop;
                            MoveToTail();
                            ConsoleWriteChar(shownCharacter);
                            Console.CursorLeft = left;
                            Console.CursorTop = top;
                            MovePositive(1);
                            InsertAt(position, keyInfo.KeyChar);
                            position++;
                        }
                    }
                }
            }
        }
    }
}