oppi.li
source dump of claude code
1/**
2 * A fixed-size circular buffer that automatically evicts the oldest items
3 * when the buffer is full. Useful for maintaining a rolling window of data.
4 */
5export class CircularBuffer<T> {
6 private buffer: T[]
7 private head = 0
8 private size = 0
9
10 constructor(private capacity: number) {
11 this.buffer = new Array(capacity)
12 }
13
14 /**
15 * Add an item to the buffer. If the buffer is full,
16 * the oldest item will be evicted.
17 */
18 add(item: T): void {
19 this.buffer[this.head] = item
20 this.head = (this.head + 1) % this.capacity
21 if (this.size < this.capacity) {
22 this.size++
23 }
24 }
25
26 /**
27 * Add multiple items to the buffer at once.
28 */
29 addAll(items: T[]): void {
30 for (const item of items) {
31 this.add(item)
32 }
33 }
34
35 /**
36 * Get the most recent N items from the buffer.
37 * Returns fewer items if the buffer contains less than N items.
38 */
39 getRecent(count: number): T[] {
40 const result: T[] = []
41 const start = this.size < this.capacity ? 0 : this.head
42 const available = Math.min(count, this.size)
43
44 for (let i = 0; i < available; i++) {
45 const index = (start + this.size - available + i) % this.capacity
46 result.push(this.buffer[index]!)
47 }
48
49 return result
50 }
51
52 /**
53 * Get all items currently in the buffer, in order from oldest to newest.
54 */
55 toArray(): T[] {
56 if (this.size === 0) return []
57
58 const result: T[] = []
59 const start = this.size < this.capacity ? 0 : this.head
60
61 for (let i = 0; i < this.size; i++) {
62 const index = (start + i) % this.capacity
63 result.push(this.buffer[index]!)
64 }
65
66 return result
67 }
68
69 /**
70 * Clear all items from the buffer.
71 */
72 clear(): void {
73 this.buffer.length = 0
74 this.head = 0
75 this.size = 0
76 }
77
78 /**
79 * Get the current number of items in the buffer.
80 */
81 length(): number {
82 return this.size
83 }
84}