Commit | Line | Data |
---|---|---|
f12182ad | 1 | /** |
db89e3bc | 2 | * Default buffer size. |
f12182ad JB |
3 | */ |
4 | export const defaultBufferSize = 2048 | |
5 | ||
6 | /** | |
c9c71898 | 7 | * Circular buffer. |
db89e3bc JB |
8 | * |
9 | * @typeParam T - Type of buffer data. | |
10 | * @internal | |
f12182ad JB |
11 | */ |
12 | export class CircularBuffer<T> { | |
cf42a4cf | 13 | private readIdx: number |
f12182ad JB |
14 | private writeIdx: number |
15 | private items: Array<T | undefined> | |
16 | private readonly maxArrayIdx: number | |
cf42a4cf | 17 | public size: number |
f12182ad JB |
18 | |
19 | /** | |
db89e3bc JB |
20 | * @param size - Buffer size. @defaultValue defaultBufferSize |
21 | * @returns CircularBuffer. | |
f12182ad JB |
22 | */ |
23 | constructor (size: number = defaultBufferSize) { | |
24 | this.checkSize(size) | |
25 | this.readIdx = 0 | |
26 | this.writeIdx = 0 | |
27 | this.maxArrayIdx = size - 1 | |
cf42a4cf | 28 | this.size = 0 |
f12182ad JB |
29 | this.items = new Array<T | undefined>(size) |
30 | } | |
31 | ||
cf42a4cf JB |
32 | /** |
33 | * Checks whether the buffer is empty. | |
34 | * | |
35 | * @returns Whether the buffer is empty. | |
36 | */ | |
37 | public empty (): boolean { | |
38 | return this.size === 0 | |
39 | } | |
40 | ||
41 | /** | |
42 | * Checks whether the buffer is full. | |
43 | * | |
44 | * @returns Whether the buffer is full. | |
45 | */ | |
46 | public full (): boolean { | |
47 | return this.size === this.items.length | |
48 | } | |
49 | ||
f12182ad | 50 | /** |
db89e3bc | 51 | * Puts data into buffer. |
f12182ad | 52 | * |
db89e3bc | 53 | * @param data - Data to put into buffer. |
f12182ad JB |
54 | */ |
55 | public put (data: T): void { | |
56 | this.items[this.writeIdx] = data | |
57 | this.writeIdx = this.writeIdx === this.maxArrayIdx ? 0 : this.writeIdx + 1 | |
cf42a4cf JB |
58 | if (this.size < this.items.length) { |
59 | ++this.size | |
60 | } | |
61 | } | |
62 | ||
63 | /** | |
64 | * Gets data from buffer. | |
65 | * | |
66 | * @returns Data from buffer. | |
67 | */ | |
68 | public get (): T | undefined { | |
69 | const data = this.items[this.readIdx] | |
70 | if (data == null) { | |
71 | return | |
72 | } | |
73 | this.items[this.readIdx] = undefined | |
74 | this.readIdx = this.readIdx === this.maxArrayIdx ? 0 : this.readIdx + 1 | |
75 | --this.size | |
76 | return data | |
f12182ad JB |
77 | } |
78 | ||
79 | /** | |
db89e3bc | 80 | * Returns buffer as array. |
f12182ad | 81 | * |
db89e3bc | 82 | * @returns Array of buffer data. |
f12182ad JB |
83 | */ |
84 | public toArray (): T[] { | |
85 | return this.items.filter(item => item != null) as T[] | |
86 | } | |
87 | ||
88 | private checkSize (size: number): void { | |
89 | if (!Number.isSafeInteger(size)) { | |
90 | throw new TypeError( | |
91 | `Invalid circular buffer size: ${size} is not an integer` | |
92 | ) | |
93 | } | |
94 | if (size < 0) { | |
95 | throw new RangeError(`Invalid circular buffer size: ${size} < 0`) | |
96 | } | |
97 | } | |
98 | } |