jellyfin/MediaBrowser.Providers/Manager/IPriorityQueue.cs
2017-04-29 22:37:51 -04:00

60 lines
2.1 KiB
C#

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace Priority_Queue
{
/// <summary>
/// Credit: https://github.com/BlueRaja/High-Speed-Priority-Queue-for-C-Sharp
/// The IPriorityQueue interface. This is mainly here for purists, and in case I decide to add more implementations later.
/// For speed purposes, it is actually recommended that you *don't* access the priority queue through this interface, since the JIT can
/// (theoretically?) optimize method calls from concrete-types slightly better.
/// </summary>
public interface IPriorityQueue<TItem, in TPriority> : IEnumerable<TItem>
where TPriority : IComparable<TPriority>
{
/// <summary>
/// Enqueue a node to the priority queue. Lower values are placed in front. Ties are broken by first-in-first-out.
/// See implementation for how duplicates are handled.
/// </summary>
void Enqueue(TItem node, TPriority priority);
/// <summary>
/// Removes the head of the queue (node with minimum priority; ties are broken by order of insertion), and returns it.
/// </summary>
TItem Dequeue();
/// <summary>
/// Removes every node from the queue.
/// </summary>
void Clear();
/// <summary>
/// Returns whether the given node is in the queue.
/// </summary>
bool Contains(TItem node);
/// <summary>
/// Removes a node from the queue. The node does not need to be the head of the queue.
/// </summary>
void Remove(TItem node);
/// <summary>
/// Call this method to change the priority of a node.
/// </summary>
void UpdatePriority(TItem node, TPriority priority);
/// <summary>
/// Returns the head of the queue, without removing it (use Dequeue() for that).
/// </summary>
TItem First { get; }
/// <summary>
/// Returns the number of nodes in the queue.
/// </summary>
int Count { get; }
}
}