| 1 | import { |
| 2 | defaultQueueSize, |
| 3 | type FixedQueueNode, |
| 4 | type IFixedQueue, |
| 5 | } from './queue-types.js' |
| 6 | |
| 7 | /** |
| 8 | * Base fixed queue class. |
| 9 | * @typeParam T - Type of fixed queue data. |
| 10 | * @internal |
| 11 | */ |
| 12 | export abstract class AbstractFixedQueue<T> implements IFixedQueue<T> { |
| 13 | protected start!: number |
| 14 | /** @inheritdoc */ |
| 15 | public readonly capacity: number |
| 16 | /** @inheritdoc */ |
| 17 | public nodeArray: FixedQueueNode<T>[] |
| 18 | /** @inheritdoc */ |
| 19 | public size!: number |
| 20 | |
| 21 | /** |
| 22 | * Constructs a fixed queue. |
| 23 | * @param size - Fixed queue size. @defaultValue defaultQueueSize |
| 24 | * @returns IFixedQueue. |
| 25 | */ |
| 26 | constructor (size: number = defaultQueueSize) { |
| 27 | this.checkSize(size) |
| 28 | this.capacity = size |
| 29 | this.nodeArray = new Array<FixedQueueNode<T>>(this.capacity) |
| 30 | this.clear() |
| 31 | } |
| 32 | |
| 33 | /** |
| 34 | * Checks the fixed queue size. |
| 35 | * @param size - Queue size. |
| 36 | */ |
| 37 | private checkSize (size: number): void { |
| 38 | if (!Number.isSafeInteger(size)) { |
| 39 | throw new TypeError( |
| 40 | `Invalid fixed queue size: '${size.toString()}' is not an integer` |
| 41 | ) |
| 42 | } |
| 43 | if (size < 0) { |
| 44 | throw new RangeError(`Invalid fixed queue size: ${size.toString()} < 0`) |
| 45 | } |
| 46 | } |
| 47 | |
| 48 | /** @inheritdoc */ |
| 49 | public clear (): void { |
| 50 | this.start = 0 |
| 51 | this.size = 0 |
| 52 | } |
| 53 | |
| 54 | /** @inheritdoc */ |
| 55 | public dequeue (): T | undefined { |
| 56 | if (this.empty()) { |
| 57 | return undefined |
| 58 | } |
| 59 | const index = this.start |
| 60 | --this.size |
| 61 | ++this.start |
| 62 | if (this.start === this.capacity) { |
| 63 | this.start = 0 |
| 64 | } |
| 65 | return this.nodeArray[index].data |
| 66 | } |
| 67 | |
| 68 | /** @inheritdoc */ |
| 69 | public empty (): boolean { |
| 70 | return this.size === 0 |
| 71 | } |
| 72 | |
| 73 | /** @inheritdoc */ |
| 74 | public abstract enqueue (data: T, priority?: number): number |
| 75 | |
| 76 | /** @inheritdoc */ |
| 77 | public full (): boolean { |
| 78 | return this.size === this.capacity |
| 79 | } |
| 80 | |
| 81 | /** @inheritdoc */ |
| 82 | public get (index: number): T | undefined { |
| 83 | if (this.empty() || index >= this.size) { |
| 84 | return undefined |
| 85 | } |
| 86 | index += this.start |
| 87 | if (index >= this.capacity) { |
| 88 | index -= this.capacity |
| 89 | } |
| 90 | return this.nodeArray[index].data |
| 91 | } |
| 92 | |
| 93 | /** @inheritdoc */ |
| 94 | public [Symbol.iterator] (): Iterator<T> { |
| 95 | let index = this.start |
| 96 | let i = 0 |
| 97 | return { |
| 98 | next: () => { |
| 99 | if (i >= this.size) { |
| 100 | return { |
| 101 | done: true, |
| 102 | value: undefined, |
| 103 | } |
| 104 | } |
| 105 | const value = this.nodeArray[index].data |
| 106 | ++index |
| 107 | ++i |
| 108 | if (index === this.capacity) { |
| 109 | index = 0 |
| 110 | } |
| 111 | return { |
| 112 | done: false, |
| 113 | value, |
| 114 | } |
| 115 | }, |
| 116 | } |
| 117 | } |
| 118 | } |