import { BaseKVStorage, type ScanOptions } from '../src/kv-storage/base-kv-storage.js'
import { KVStorageInMemory } from '../src/kv-storage/kv-storage-in-memory.js'

export async function collect<T>(iterable: AsyncIterable<T>): Promise<T[]> {
  const out: T[] = []
  for await (const item of iterable) out.push(item)
  return out
}

/**
 * Wraps another KV storage and counts primitive calls. Also shows the wrapper pattern
 * (e.g. an encryption layer): extend BaseKVStorage and delegate the five primitives.
 * Counts are reported under the public method names (writeMany, removeMany, writeIfAbsent).
 */
export class KVStorageCounting extends BaseKVStorage {
  calls: Record<string, number> = {}

  constructor(readonly inner: BaseKVStorage = new KVStorageInMemory()) {
    super()
  }

  reset(): void {
    this.calls = {}
  }

  readMany(keys: string[]) {
    return this.count('readMany', () => this.inner.readMany(keys))
  }
  protected applyWrite(entries: [string, unknown][]) {
    return this.count('writeMany', () => this.inner.writeMany(entries))
  }
  protected applyRemove(keys: string[]) {
    return this.count('removeMany', () => this.inner.removeMany(keys))
  }
  protected applyWriteIfAbsent(entries: [string, unknown][]) {
    return this.count('writeIfAbsent', () => this.inner.writeIfAbsent(entries))
  }
  scan(options?: ScanOptions) {
    return this.count('scan', () => this.inner.scan(options))
  }

  private count<T>(name: string, fn: () => T): T {
    this.calls[name] = (this.calls[name] ?? 0) + 1
    return fn()
  }
}