mirror of
https://github.com/jellyfin/jellyfin.git
synced 2024-09-06 19:37:55 +02:00
Merge pull request #950 from cvium/replace_priority_queue
Replace OptimizedPriorityQueue source with NuGet reference
This commit is contained in:
commit
44ed037e73
6 changed files with 2 additions and 752 deletions
|
@ -1,402 +0,0 @@
|
|||
using System;
|
||||
using System.Collections;
|
||||
using System.Collections.Generic;
|
||||
using System.Runtime.CompilerServices;
|
||||
|
||||
//TODO Fix namespace or replace
|
||||
namespace Priority_Queue
|
||||
{
|
||||
/// <summary>
|
||||
/// Credit: https://github.com/BlueRaja/High-Speed-Priority-Queue-for-C-Sharp
|
||||
/// A copy of StablePriorityQueue which also has generic priority-type
|
||||
/// </summary>
|
||||
/// <typeparam name="TItem">The values in the queue. Must extend the GenericPriorityQueue class</typeparam>
|
||||
/// <typeparam name="TPriority">The priority-type. Must extend IComparable<TPriority></typeparam>
|
||||
public sealed class GenericPriorityQueue<TItem, TPriority> : IFixedSizePriorityQueue<TItem, TPriority>
|
||||
where TItem : GenericPriorityQueueNode<TPriority>
|
||||
where TPriority : IComparable<TPriority>
|
||||
{
|
||||
private int _numNodes;
|
||||
private TItem[] _nodes;
|
||||
private long _numNodesEverEnqueued;
|
||||
|
||||
/// <summary>
|
||||
/// Instantiate a new Priority Queue
|
||||
/// </summary>
|
||||
/// <param name="maxNodes">The max nodes ever allowed to be enqueued (going over this will cause undefined behavior)</param>
|
||||
public GenericPriorityQueue(int maxNodes)
|
||||
{
|
||||
#if DEBUG
|
||||
if (maxNodes <= 0)
|
||||
{
|
||||
throw new InvalidOperationException("New queue size cannot be smaller than 1");
|
||||
}
|
||||
#endif
|
||||
|
||||
_numNodes = 0;
|
||||
_nodes = new TItem[maxNodes + 1];
|
||||
_numNodesEverEnqueued = 0;
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Returns the number of nodes in the queue.
|
||||
/// O(1)
|
||||
/// </summary>
|
||||
public int Count => _numNodes;
|
||||
|
||||
/// <summary>
|
||||
/// Returns the maximum number of items that can be enqueued at once in this queue. Once you hit this number (ie. once Count == MaxSize),
|
||||
/// attempting to enqueue another item will cause undefined behavior. O(1)
|
||||
/// </summary>
|
||||
public int MaxSize => _nodes.Length - 1;
|
||||
|
||||
/// <summary>
|
||||
/// Removes every node from the queue.
|
||||
/// O(n) (So, don't do this often!)
|
||||
/// </summary>
|
||||
[MethodImpl(MethodImplOptions.AggressiveInlining)]
|
||||
public void Clear()
|
||||
{
|
||||
Array.Clear(_nodes, 1, _numNodes);
|
||||
_numNodes = 0;
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Returns (in O(1)!) whether the given node is in the queue. O(1)
|
||||
/// </summary>
|
||||
[MethodImpl(MethodImplOptions.AggressiveInlining)]
|
||||
public bool Contains(TItem node)
|
||||
{
|
||||
#if DEBUG
|
||||
if (node == null)
|
||||
{
|
||||
throw new ArgumentNullException(nameof(node));
|
||||
}
|
||||
if (node.QueueIndex < 0 || node.QueueIndex >= _nodes.Length)
|
||||
{
|
||||
throw new InvalidOperationException("node.QueueIndex has been corrupted. Did you change it manually? Or add this node to another queue?");
|
||||
}
|
||||
#endif
|
||||
|
||||
return (_nodes[node.QueueIndex] == node);
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Enqueue a node to the priority queue. Lower values are placed in front. Ties are broken by first-in-first-out.
|
||||
/// If the queue is full, the result is undefined.
|
||||
/// If the node is already enqueued, the result is undefined.
|
||||
/// O(log n)
|
||||
/// </summary>
|
||||
[MethodImpl(MethodImplOptions.AggressiveInlining)]
|
||||
public void Enqueue(TItem node, TPriority priority)
|
||||
{
|
||||
#if DEBUG
|
||||
if (node == null)
|
||||
{
|
||||
throw new ArgumentNullException(nameof(node));
|
||||
}
|
||||
if (_numNodes >= _nodes.Length - 1)
|
||||
{
|
||||
throw new InvalidOperationException("Queue is full - node cannot be added: " + node);
|
||||
}
|
||||
if (Contains(node))
|
||||
{
|
||||
throw new InvalidOperationException("Node is already enqueued: " + node);
|
||||
}
|
||||
#endif
|
||||
|
||||
node.Priority = priority;
|
||||
_numNodes++;
|
||||
_nodes[_numNodes] = node;
|
||||
node.QueueIndex = _numNodes;
|
||||
node.InsertionIndex = _numNodesEverEnqueued++;
|
||||
CascadeUp(_nodes[_numNodes]);
|
||||
}
|
||||
|
||||
[MethodImpl(MethodImplOptions.AggressiveInlining)]
|
||||
private void Swap(TItem node1, TItem node2)
|
||||
{
|
||||
//Swap the nodes
|
||||
_nodes[node1.QueueIndex] = node2;
|
||||
_nodes[node2.QueueIndex] = node1;
|
||||
|
||||
//Swap their indicies
|
||||
int temp = node1.QueueIndex;
|
||||
node1.QueueIndex = node2.QueueIndex;
|
||||
node2.QueueIndex = temp;
|
||||
}
|
||||
|
||||
//Performance appears to be slightly better when this is NOT inlined o_O
|
||||
private void CascadeUp(TItem node)
|
||||
{
|
||||
//aka Heapify-up
|
||||
int parent = node.QueueIndex / 2;
|
||||
while (parent >= 1)
|
||||
{
|
||||
var parentNode = _nodes[parent];
|
||||
if (HasHigherPriority(parentNode, node))
|
||||
break;
|
||||
|
||||
//Node has lower priority value, so move it up the heap
|
||||
Swap(node, parentNode); //For some reason, this is faster with Swap() rather than (less..?) individual operations, like in CascadeDown()
|
||||
|
||||
parent = node.QueueIndex / 2;
|
||||
}
|
||||
}
|
||||
|
||||
[MethodImpl(MethodImplOptions.AggressiveInlining)]
|
||||
private void CascadeDown(TItem node)
|
||||
{
|
||||
//aka Heapify-down
|
||||
TItem newParent;
|
||||
int finalQueueIndex = node.QueueIndex;
|
||||
while (true)
|
||||
{
|
||||
newParent = node;
|
||||
int childLeftIndex = 2 * finalQueueIndex;
|
||||
|
||||
//Check if the left-child is higher-priority than the current node
|
||||
if (childLeftIndex > _numNodes)
|
||||
{
|
||||
//This could be placed outside the loop, but then we'd have to check newParent != node twice
|
||||
node.QueueIndex = finalQueueIndex;
|
||||
_nodes[finalQueueIndex] = node;
|
||||
break;
|
||||
}
|
||||
|
||||
var childLeft = _nodes[childLeftIndex];
|
||||
if (HasHigherPriority(childLeft, newParent))
|
||||
{
|
||||
newParent = childLeft;
|
||||
}
|
||||
|
||||
//Check if the right-child is higher-priority than either the current node or the left child
|
||||
int childRightIndex = childLeftIndex + 1;
|
||||
if (childRightIndex <= _numNodes)
|
||||
{
|
||||
var childRight = _nodes[childRightIndex];
|
||||
if (HasHigherPriority(childRight, newParent))
|
||||
{
|
||||
newParent = childRight;
|
||||
}
|
||||
}
|
||||
|
||||
//If either of the children has higher (smaller) priority, swap and continue cascading
|
||||
if (newParent != node)
|
||||
{
|
||||
//Move new parent to its new index. node will be moved once, at the end
|
||||
//Doing it this way is one less assignment operation than calling Swap()
|
||||
_nodes[finalQueueIndex] = newParent;
|
||||
|
||||
int temp = newParent.QueueIndex;
|
||||
newParent.QueueIndex = finalQueueIndex;
|
||||
finalQueueIndex = temp;
|
||||
}
|
||||
else
|
||||
{
|
||||
//See note above
|
||||
node.QueueIndex = finalQueueIndex;
|
||||
_nodes[finalQueueIndex] = node;
|
||||
break;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Returns true if 'higher' has higher priority than 'lower', false otherwise.
|
||||
/// Note that calling HasHigherPriority(node, node) (ie. both arguments the same node) will return false
|
||||
/// </summary>
|
||||
[MethodImpl(MethodImplOptions.AggressiveInlining)]
|
||||
private bool HasHigherPriority(TItem higher, TItem lower)
|
||||
{
|
||||
var cmp = higher.Priority.CompareTo(lower.Priority);
|
||||
return (cmp < 0 || (cmp == 0 && higher.InsertionIndex < lower.InsertionIndex));
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Removes the head of the queue (node with minimum priority; ties are broken by order of insertion), and returns it.
|
||||
/// If queue is empty, result is undefined
|
||||
/// O(log n)
|
||||
/// </summary>
|
||||
public bool TryDequeue(out TItem item)
|
||||
{
|
||||
if (_numNodes <= 0)
|
||||
{
|
||||
item = default(TItem);
|
||||
return false;
|
||||
}
|
||||
|
||||
#if DEBUG
|
||||
|
||||
if (!IsValidQueue())
|
||||
{
|
||||
throw new InvalidOperationException("Queue has been corrupted (Did you update a node priority manually instead of calling UpdatePriority()?" +
|
||||
"Or add the same node to two different queues?)");
|
||||
}
|
||||
#endif
|
||||
|
||||
var returnMe = _nodes[1];
|
||||
Remove(returnMe);
|
||||
item = returnMe;
|
||||
return true;
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Resize the queue so it can accept more nodes. All currently enqueued nodes are remain.
|
||||
/// Attempting to decrease the queue size to a size too small to hold the existing nodes results in undefined behavior
|
||||
/// O(n)
|
||||
/// </summary>
|
||||
public void Resize(int maxNodes)
|
||||
{
|
||||
#if DEBUG
|
||||
if (maxNodes <= 0)
|
||||
{
|
||||
throw new InvalidOperationException("Queue size cannot be smaller than 1");
|
||||
}
|
||||
|
||||
if (maxNodes < _numNodes)
|
||||
{
|
||||
throw new InvalidOperationException("Called Resize(" + maxNodes + "), but current queue contains " + _numNodes + " nodes");
|
||||
}
|
||||
#endif
|
||||
|
||||
TItem[] newArray = new TItem[maxNodes + 1];
|
||||
int highestIndexToCopy = Math.Min(maxNodes, _numNodes);
|
||||
for (int i = 1; i <= highestIndexToCopy; i++)
|
||||
{
|
||||
newArray[i] = _nodes[i];
|
||||
}
|
||||
_nodes = newArray;
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Returns the head of the queue, without removing it (use Dequeue() for that).
|
||||
/// If the queue is empty, behavior is undefined.
|
||||
/// O(1)
|
||||
/// </summary>
|
||||
public TItem First
|
||||
{
|
||||
get
|
||||
{
|
||||
#if DEBUG
|
||||
if (_numNodes <= 0)
|
||||
{
|
||||
throw new InvalidOperationException("Cannot call .First on an empty queue");
|
||||
}
|
||||
#endif
|
||||
|
||||
return _nodes[1];
|
||||
}
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// This method must be called on a node every time its priority changes while it is in the queue.
|
||||
/// <b>Forgetting to call this method will result in a corrupted queue!</b>
|
||||
/// Calling this method on a node not in the queue results in undefined behavior
|
||||
/// O(log n)
|
||||
/// </summary>
|
||||
[MethodImpl(MethodImplOptions.AggressiveInlining)]
|
||||
public void UpdatePriority(TItem node, TPriority priority)
|
||||
{
|
||||
#if DEBUG
|
||||
if (node == null)
|
||||
{
|
||||
throw new ArgumentNullException(nameof(node));
|
||||
}
|
||||
if (!Contains(node))
|
||||
{
|
||||
throw new InvalidOperationException("Cannot call UpdatePriority() on a node which is not enqueued: " + node);
|
||||
}
|
||||
#endif
|
||||
|
||||
node.Priority = priority;
|
||||
OnNodeUpdated(node);
|
||||
}
|
||||
|
||||
private void OnNodeUpdated(TItem node)
|
||||
{
|
||||
//Bubble the updated node up or down as appropriate
|
||||
int parentIndex = node.QueueIndex / 2;
|
||||
var parentNode = _nodes[parentIndex];
|
||||
|
||||
if (parentIndex > 0 && HasHigherPriority(node, parentNode))
|
||||
{
|
||||
CascadeUp(node);
|
||||
}
|
||||
else
|
||||
{
|
||||
//Note that CascadeDown will be called if parentNode == node (that is, node is the root)
|
||||
CascadeDown(node);
|
||||
}
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Removes a node from the queue. The node does not need to be the head of the queue.
|
||||
/// If the node is not in the queue, the result is undefined. If unsure, check Contains() first
|
||||
/// O(log n)
|
||||
/// </summary>
|
||||
public void Remove(TItem node)
|
||||
{
|
||||
#if DEBUG
|
||||
if (node == null)
|
||||
{
|
||||
throw new ArgumentNullException(nameof(node));
|
||||
}
|
||||
if (!Contains(node))
|
||||
{
|
||||
throw new InvalidOperationException("Cannot call Remove() on a node which is not enqueued: " + node);
|
||||
}
|
||||
#endif
|
||||
|
||||
//If the node is already the last node, we can remove it immediately
|
||||
if (node.QueueIndex == _numNodes)
|
||||
{
|
||||
_nodes[_numNodes] = null;
|
||||
_numNodes--;
|
||||
return;
|
||||
}
|
||||
|
||||
//Swap the node with the last node
|
||||
var formerLastNode = _nodes[_numNodes];
|
||||
Swap(node, formerLastNode);
|
||||
_nodes[_numNodes] = null;
|
||||
_numNodes--;
|
||||
|
||||
//Now bubble formerLastNode (which is no longer the last node) up or down as appropriate
|
||||
OnNodeUpdated(formerLastNode);
|
||||
}
|
||||
|
||||
public IEnumerator<TItem> GetEnumerator()
|
||||
{
|
||||
for (int i = 1; i <= _numNodes; i++)
|
||||
yield return _nodes[i];
|
||||
}
|
||||
|
||||
IEnumerator IEnumerable.GetEnumerator()
|
||||
{
|
||||
return GetEnumerator();
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// <b>Should not be called in production code.</b>
|
||||
/// Checks to make sure the queue is still in a valid state. Used for testing/debugging the queue.
|
||||
/// </summary>
|
||||
public bool IsValidQueue()
|
||||
{
|
||||
for (int i = 1; i < _nodes.Length; i++)
|
||||
{
|
||||
if (_nodes[i] != null)
|
||||
{
|
||||
int childLeftIndex = 2 * i;
|
||||
if (childLeftIndex < _nodes.Length && _nodes[childLeftIndex] != null && HasHigherPriority(_nodes[childLeftIndex], _nodes[i]))
|
||||
return false;
|
||||
|
||||
int childRightIndex = childLeftIndex + 1;
|
||||
if (childRightIndex < _nodes.Length && _nodes[childRightIndex] != null && HasHigherPriority(_nodes[childRightIndex], _nodes[i]))
|
||||
return false;
|
||||
}
|
||||
}
|
||||
return true;
|
||||
}
|
||||
}
|
||||
}
|
|
@ -1,22 +0,0 @@
|
|||
namespace Priority_Queue
|
||||
{
|
||||
/// Credit: https://github.com/BlueRaja/High-Speed-Priority-Queue-for-C-Sharp
|
||||
public class GenericPriorityQueueNode<TPriority>
|
||||
{
|
||||
/// <summary>
|
||||
/// The Priority to insert this node at. Must be set BEFORE adding a node to the queue (ideally just once, in the node's constructor).
|
||||
/// Should not be manually edited once the node has been enqueued - use queue.UpdatePriority() instead
|
||||
/// </summary>
|
||||
public TPriority Priority { get; protected internal set; }
|
||||
|
||||
/// <summary>
|
||||
/// Represents the current position in the queue
|
||||
/// </summary>
|
||||
public int QueueIndex { get; internal set; }
|
||||
|
||||
/// <summary>
|
||||
/// Represents the order the node was inserted in
|
||||
/// </summary>
|
||||
public long InsertionIndex { get; internal set; }
|
||||
}
|
||||
}
|
|
@ -1,24 +0,0 @@
|
|||
using System;
|
||||
|
||||
namespace Priority_Queue
|
||||
{
|
||||
/// <summary>
|
||||
/// Credit: https://github.com/BlueRaja/High-Speed-Priority-Queue-for-C-Sharp
|
||||
/// A helper-interface only needed to make writing unit tests a bit easier (hence the 'internal' access modifier)
|
||||
/// </summary>
|
||||
internal interface IFixedSizePriorityQueue<TItem, in TPriority> : IPriorityQueue<TItem, TPriority>
|
||||
where TPriority : IComparable<TPriority>
|
||||
{
|
||||
/// <summary>
|
||||
/// Resize the queue so it can accept more nodes. All currently enqueued nodes are remain.
|
||||
/// Attempting to decrease the queue size to a size too small to hold the existing nodes results in undefined behavior
|
||||
/// </summary>
|
||||
void Resize(int maxNodes);
|
||||
|
||||
/// <summary>
|
||||
/// Returns the maximum number of items that can be enqueued at once in this queue. Once you hit this number (ie. once Count == MaxSize),
|
||||
/// attempting to enqueue another item will cause undefined behavior.
|
||||
/// </summary>
|
||||
int MaxSize { get; }
|
||||
}
|
||||
}
|
|
@ -1,56 +0,0 @@
|
|||
using System;
|
||||
using System.Collections.Generic;
|
||||
|
||||
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>
|
||||
bool TryDequeue(out TItem item);
|
||||
|
||||
/// <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; }
|
||||
}
|
||||
}
|
|
@ -1,247 +0,0 @@
|
|||
using System;
|
||||
using System.Collections;
|
||||
using System.Collections.Generic;
|
||||
|
||||
namespace Priority_Queue
|
||||
{
|
||||
/// <summary>
|
||||
/// Credit: https://github.com/BlueRaja/High-Speed-Priority-Queue-for-C-Sharp
|
||||
/// A simplified priority queue implementation. Is stable, auto-resizes, and thread-safe, at the cost of being slightly slower than
|
||||
/// FastPriorityQueue
|
||||
/// </summary>
|
||||
/// <typeparam name="TItem">The type to enqueue</typeparam>
|
||||
/// <typeparam name="TPriority">The priority-type to use for nodes. Must extend IComparable<TPriority></typeparam>
|
||||
public class SimplePriorityQueue<TItem, TPriority> : IPriorityQueue<TItem, TPriority>
|
||||
where TPriority : IComparable<TPriority>
|
||||
{
|
||||
private class SimpleNode : GenericPriorityQueueNode<TPriority>
|
||||
{
|
||||
public TItem Data { get; private set; }
|
||||
|
||||
public SimpleNode(TItem data)
|
||||
{
|
||||
Data = data;
|
||||
}
|
||||
}
|
||||
|
||||
private const int INITIAL_QUEUE_SIZE = 10;
|
||||
private readonly GenericPriorityQueue<SimpleNode, TPriority> _queue;
|
||||
|
||||
public SimplePriorityQueue()
|
||||
{
|
||||
_queue = new GenericPriorityQueue<SimpleNode, TPriority>(INITIAL_QUEUE_SIZE);
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Given an item of type T, returns the exist SimpleNode in the queue
|
||||
/// </summary>
|
||||
private SimpleNode GetExistingNode(TItem item)
|
||||
{
|
||||
var comparer = EqualityComparer<TItem>.Default;
|
||||
foreach (var node in _queue)
|
||||
{
|
||||
if (comparer.Equals(node.Data, item))
|
||||
{
|
||||
return node;
|
||||
}
|
||||
}
|
||||
throw new InvalidOperationException("Item cannot be found in queue: " + item);
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Returns the number of nodes in the queue.
|
||||
/// O(1)
|
||||
/// </summary>
|
||||
public int Count
|
||||
{
|
||||
get
|
||||
{
|
||||
lock (_queue)
|
||||
{
|
||||
return _queue.Count;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
/// <summary>
|
||||
/// Returns the head of the queue, without removing it (use Dequeue() for that).
|
||||
/// Throws an exception when the queue is empty.
|
||||
/// O(1)
|
||||
/// </summary>
|
||||
public TItem First
|
||||
{
|
||||
get
|
||||
{
|
||||
lock (_queue)
|
||||
{
|
||||
if (_queue.Count <= 0)
|
||||
{
|
||||
throw new InvalidOperationException("Cannot call .First on an empty queue");
|
||||
}
|
||||
|
||||
SimpleNode first = _queue.First;
|
||||
return (first != null ? first.Data : default(TItem));
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Removes every node from the queue.
|
||||
/// O(n)
|
||||
/// </summary>
|
||||
public void Clear()
|
||||
{
|
||||
lock (_queue)
|
||||
{
|
||||
_queue.Clear();
|
||||
}
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Returns whether the given item is in the queue.
|
||||
/// O(n)
|
||||
/// </summary>
|
||||
public bool Contains(TItem item)
|
||||
{
|
||||
lock (_queue)
|
||||
{
|
||||
var comparer = EqualityComparer<TItem>.Default;
|
||||
foreach (var node in _queue)
|
||||
{
|
||||
if (comparer.Equals(node.Data, item))
|
||||
{
|
||||
return true;
|
||||
}
|
||||
}
|
||||
return false;
|
||||
}
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Removes the head of the queue (node with minimum priority; ties are broken by order of insertion), and returns it.
|
||||
/// If queue is empty, throws an exception
|
||||
/// O(log n)
|
||||
/// </summary>
|
||||
public bool TryDequeue(out TItem item)
|
||||
{
|
||||
lock (_queue)
|
||||
{
|
||||
if (_queue.Count <= 0)
|
||||
{
|
||||
item = default(TItem);
|
||||
return false;
|
||||
}
|
||||
|
||||
if (_queue.TryDequeue(out SimpleNode node))
|
||||
{
|
||||
item = node.Data;
|
||||
return true;
|
||||
}
|
||||
|
||||
item = default(TItem);
|
||||
return false;
|
||||
}
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Enqueue a node to the priority queue. Lower values are placed in front. Ties are broken by first-in-first-out.
|
||||
/// This queue automatically resizes itself, so there's no concern of the queue becoming 'full'.
|
||||
/// Duplicates are allowed.
|
||||
/// O(log n)
|
||||
/// </summary>
|
||||
public void Enqueue(TItem item, TPriority priority)
|
||||
{
|
||||
lock (_queue)
|
||||
{
|
||||
var node = new SimpleNode(item);
|
||||
if (_queue.Count == _queue.MaxSize)
|
||||
{
|
||||
_queue.Resize(_queue.MaxSize * 2 + 1);
|
||||
}
|
||||
_queue.Enqueue(node, priority);
|
||||
}
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Removes an item from the queue. The item does not need to be the head of the queue.
|
||||
/// If the item is not in the queue, an exception is thrown. If unsure, check Contains() first.
|
||||
/// If multiple copies of the item are enqueued, only the first one is removed.
|
||||
/// O(n)
|
||||
/// </summary>
|
||||
public void Remove(TItem item)
|
||||
{
|
||||
lock (_queue)
|
||||
{
|
||||
try
|
||||
{
|
||||
_queue.Remove(GetExistingNode(item));
|
||||
}
|
||||
catch (InvalidOperationException ex)
|
||||
{
|
||||
throw new InvalidOperationException("Cannot call Remove() on a node which is not enqueued: " + item, ex);
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// Call this method to change the priority of an item.
|
||||
/// Calling this method on a item not in the queue will throw an exception.
|
||||
/// If the item is enqueued multiple times, only the first one will be updated.
|
||||
/// (If your requirements are complex enough that you need to enqueue the same item multiple times <i>and</i> be able
|
||||
/// to update all of them, please wrap your items in a wrapper class so they can be distinguished).
|
||||
/// O(n)
|
||||
/// </summary>
|
||||
public void UpdatePriority(TItem item, TPriority priority)
|
||||
{
|
||||
lock (_queue)
|
||||
{
|
||||
try
|
||||
{
|
||||
SimpleNode updateMe = GetExistingNode(item);
|
||||
_queue.UpdatePriority(updateMe, priority);
|
||||
}
|
||||
catch (InvalidOperationException ex)
|
||||
{
|
||||
throw new InvalidOperationException("Cannot call UpdatePriority() on a node which is not enqueued: " + item, ex);
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
public IEnumerator<TItem> GetEnumerator()
|
||||
{
|
||||
var queueData = new List<TItem>();
|
||||
lock (_queue)
|
||||
{
|
||||
//Copy to a separate list because we don't want to 'yield return' inside a lock
|
||||
foreach (var node in _queue)
|
||||
{
|
||||
queueData.Add(node.Data);
|
||||
}
|
||||
}
|
||||
|
||||
return queueData.GetEnumerator();
|
||||
}
|
||||
|
||||
IEnumerator IEnumerable.GetEnumerator()
|
||||
{
|
||||
return GetEnumerator();
|
||||
}
|
||||
|
||||
public bool IsValidQueue()
|
||||
{
|
||||
lock (_queue)
|
||||
{
|
||||
return _queue.IsValidQueue();
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
/// <summary>
|
||||
/// A simplified priority queue implementation. Is stable, auto-resizes, and thread-safe, at the cost of being slightly slower than
|
||||
/// FastPriorityQueue
|
||||
/// This class is kept here for backwards compatibility. It's recommended you use Simple
|
||||
/// </summary>
|
||||
/// <typeparam name="TItem">The type to enqueue</typeparam>
|
||||
public class SimplePriorityQueue<TItem> : SimplePriorityQueue<TItem, float> { }
|
||||
}
|
|
@ -1,4 +1,4 @@
|
|||
<Project Sdk="Microsoft.NET.Sdk">
|
||||
<Project Sdk="Microsoft.NET.Sdk">
|
||||
|
||||
<ItemGroup>
|
||||
<ProjectReference Include="..\MediaBrowser.Controller\MediaBrowser.Controller.csproj" />
|
||||
|
@ -11,6 +11,7 @@
|
|||
</ItemGroup>
|
||||
|
||||
<ItemGroup>
|
||||
<PackageReference Include="OptimizedPriorityQueue" Version="4.2.0" />
|
||||
<PackageReference Include="PlaylistsNET" Version="1.0.2" />
|
||||
</ItemGroup>
|
||||
|
||||
|
|
Loading…
Reference in a new issue