Commit | Line | Data |
---|---|---|
f8d5d8fd JB |
1 | /** |
2 | * Default buffer size. | |
3 | */ | |
4 | export const defaultQueueSize = 2048 | |
5 | ||
6 | /** | |
65c178f1 | 7 | * Fixed priority queue node. |
f8d5d8fd JB |
8 | * |
9 | * @typeParam T - Type of priority queue node data. | |
10 | * @internal | |
11 | */ | |
65c178f1 | 12 | export interface FixedPriorityQueueNode<T> { |
f8d5d8fd JB |
13 | data: T |
14 | priority: number | |
15 | } | |
16 | ||
eadb37e2 JB |
17 | /** |
18 | * Fixed priority queue. | |
19 | * | |
20 | * @typeParam T - Type of fixed priority queue data. | |
21 | * @internal | |
22 | */ | |
f8d5d8fd JB |
23 | export class FixedPriorityQueue<T> { |
24 | private start!: number | |
65c178f1 | 25 | private readonly nodeArray: Array<FixedPriorityQueueNode<T>> |
10b1b252 | 26 | /** The fixed priority queue capacity. */ |
9df282a0 | 27 | public readonly capacity: number |
fcfc3353 | 28 | /** The fixed priority queue size. */ |
f8d5d8fd | 29 | public size!: number |
fcfc3353 JB |
30 | /** Whether to enable priority. */ |
31 | public enablePriority: boolean | |
f8d5d8fd | 32 | |
9df282a0 JB |
33 | /** |
34 | * Constructs a fixed priority queue. | |
35 | * | |
36 | * @param size - Fixed priority queue size. @defaultValue defaultQueueSize | |
fcfc3353 | 37 | * @param enablePriority - Whether to enable priority. @defaultValue false |
9df282a0 JB |
38 | * @returns FixedPriorityQueue. |
39 | */ | |
fcfc3353 | 40 | constructor (size: number = defaultQueueSize, enablePriority = false) { |
f8d5d8fd | 41 | this.checkSize(size) |
9df282a0 | 42 | this.capacity = size |
fcfc3353 | 43 | this.enablePriority = enablePriority |
65c178f1 | 44 | this.nodeArray = new Array<FixedPriorityQueueNode<T>>(this.capacity) |
f8d5d8fd JB |
45 | this.clear() |
46 | } | |
47 | ||
e75373e6 JB |
48 | /** |
49 | * Checks if the fixed priority queue is empty. | |
50 | * | |
51 | * @returns `true` if the fixed priority queue is empty, `false` otherwise. | |
52 | */ | |
f8d5d8fd JB |
53 | public empty (): boolean { |
54 | return this.size === 0 | |
55 | } | |
56 | ||
e75373e6 JB |
57 | /** |
58 | * Checks if the fixed priority queue is full. | |
59 | * | |
60 | * @returns `true` if the fixed priority queue is full, `false` otherwise. | |
61 | */ | |
f8d5d8fd | 62 | public full (): boolean { |
9df282a0 | 63 | return this.size === this.capacity |
f8d5d8fd JB |
64 | } |
65 | ||
e75373e6 JB |
66 | /** |
67 | * Enqueue data into the fixed priority queue. | |
68 | * | |
69 | * @param data - Data to enqueue. | |
70 | * @param priority - Priority of the data. Lower values have higher priority. | |
71 | * @returns The new size of the priority queue. | |
13ed544a | 72 | * @throws If the fixed priority queue is full. |
e75373e6 | 73 | */ |
f8d5d8fd JB |
74 | public enqueue (data: T, priority?: number): number { |
75 | if (this.full()) { | |
76 | throw new Error('Priority queue is full') | |
77 | } | |
78 | priority = priority ?? 0 | |
79 | let inserted = false | |
fcfc3353 JB |
80 | if (this.enablePriority) { |
81 | let index = this.start | |
82 | for (let i = 0; i < this.size; i++) { | |
83 | if (this.nodeArray[index].priority > priority) { | |
84 | this.nodeArray.splice(index, 0, { data, priority }) | |
85 | this.nodeArray.length !== this.capacity && | |
86 | (this.nodeArray.length = this.capacity) | |
87 | inserted = true | |
88 | break | |
89 | } | |
90 | ++index | |
91 | if (index === this.capacity) { | |
92 | index = 0 | |
93 | } | |
3451940f | 94 | } |
f8d5d8fd JB |
95 | } |
96 | if (!inserted) { | |
97 | let index = this.start + this.size | |
9df282a0 JB |
98 | if (index >= this.capacity) { |
99 | index -= this.capacity | |
f8d5d8fd JB |
100 | } |
101 | this.nodeArray[index] = { data, priority } | |
102 | } | |
10b1b252 | 103 | return ++this.size |
f8d5d8fd JB |
104 | } |
105 | ||
1d98bad2 JB |
106 | /** |
107 | * Gets data from the fixed priority queue. | |
108 | * | |
109 | * @param index - The index of the data to get. | |
110 | * @returns The data at the index or `undefined` if the fixed priority queue is empty or the index is out of bounds. | |
111 | */ | |
112 | public get (index: number): T | undefined { | |
113 | if (this.empty() || index >= this.size) { | |
114 | return undefined | |
115 | } | |
116 | index += this.start | |
117 | if (index >= this.capacity) { | |
118 | index -= this.capacity | |
119 | } | |
120 | return this.nodeArray[index].data | |
121 | } | |
122 | ||
e75373e6 JB |
123 | /** |
124 | * Dequeue data from the fixed priority queue. | |
125 | * | |
126 | * @returns The dequeued data or `undefined` if the priority queue is empty. | |
127 | */ | |
f8d5d8fd JB |
128 | public dequeue (): T | undefined { |
129 | if (this.empty()) { | |
130 | return undefined | |
131 | } | |
132 | const index = this.start | |
133 | --this.size | |
134 | ++this.start | |
9df282a0 | 135 | if (this.start === this.capacity) { |
f8d5d8fd JB |
136 | this.start = 0 |
137 | } | |
138 | return this.nodeArray[index].data | |
139 | } | |
140 | ||
141 | /** | |
142 | * Clears the fixed priority queue. | |
143 | */ | |
144 | public clear (): void { | |
145 | this.start = 0 | |
146 | this.size = 0 | |
f8d5d8fd JB |
147 | } |
148 | ||
149 | /** | |
150 | * Returns an iterator for the fixed priority queue. | |
151 | * | |
152 | * @returns An iterator for the fixed priority queue. | |
153 | * @see https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Iteration_protocols | |
154 | */ | |
9df282a0 | 155 | public [Symbol.iterator] (): Iterator<T> { |
3451940f JB |
156 | let index = this.start |
157 | let i = 0 | |
f8d5d8fd JB |
158 | return { |
159 | next: () => { | |
160 | if (i >= this.size) { | |
161 | return { | |
162 | value: undefined, | |
163 | done: true | |
164 | } | |
165 | } | |
3451940f | 166 | const value = this.nodeArray[index].data |
02c769d0 JB |
167 | ++index |
168 | ++i | |
9df282a0 | 169 | if (index === this.capacity) { |
3451940f JB |
170 | index = 0 |
171 | } | |
f8d5d8fd JB |
172 | return { |
173 | value, | |
174 | done: false | |
175 | } | |
176 | } | |
177 | } | |
178 | } | |
179 | ||
e75373e6 | 180 | /** |
fcfc3353 | 181 | * Checks the queue size. |
e75373e6 | 182 | * |
fcfc3353 | 183 | * @param size - Queue size. |
e75373e6 | 184 | */ |
f8d5d8fd JB |
185 | private checkSize (size: number): void { |
186 | if (!Number.isSafeInteger(size)) { | |
187 | throw new TypeError( | |
f45a8925 | 188 | `Invalid fixed priority queue size: '${size}' is not an integer` |
f8d5d8fd JB |
189 | ) |
190 | } | |
191 | if (size < 0) { | |
192 | throw new RangeError(`Invalid fixed priority queue size: ${size} < 0`) | |
193 | } | |
194 | } | |
195 | } |