using System;

namespace FastColoredTextBoxNS

{

/// <summary>

/// Limited stack

/// </summary>

public class LimitedStack<T>

{

T[] items;

int count;

int start;

/// <summary>

/// Max stack length

/// </summary>

public int MaxItemCount

{

get { return items.Length; }

}

/// <summary>

/// Current length of stack

/// </summary>

public int Count

{

get { return count; }

}

/// <summary>

/// Constructor

/// </summary>

/// <param name="maxItemCount">Maximum length of stack</param>

public LimitedStack(int maxItemCount)

{

items = new T[maxItemCount];

count = 0;

start = 0;

}

/// <summary>

/// Pop item

/// </summary>

public T Pop()

{

if (count == 0)

throw new Exception("Stack is empty");

int i = LastIndex;

T item = items[i];

items[i] = default(T);

count--;

return item;

}

int LastIndex

{

get { return (start + count - 1) % items.Length; }

}

/// <summary>

/// Peek item

/// </summary>

public T Peek()

{

if (count == 0)

return default(T);

return items[LastIndex];

}

/// <summary>

/// Push item

/// </summary>

public void Push(T item)

{

if (count == items.Length)

start = (start + 1) % items.Length;

else

count++;

items[LastIndex] = item;

}

/// <summary>

/// Clear stack

/// </summary>

public void Clear()

{

items = new T[items.Length];

count = 0;

start = 0;

}

public T[] ToArray()

{

T[] result = new T[count];

for (int i = 0; i < count; i++)

result[i] = items[(start + i) % items.Length];

return result;

}

}

}