@bsv/sdk/src/primitives/Random.ts

BSV Blockchain Software Development Kit

class Rand {
  _rand: (n: number) => number[] // ✅ Explicit function type

  constructor () {
    const noRand = (): never => {
      throw new Error(
        'No secure random number generator is available in this environment.'
      )
    }

    this._rand = noRand // Assign the function

    if (typeof self === 'object') {
      /* eslint-disable-next-line */
      if (self.crypto?.getRandomValues) {
        this._rand = (n) => {
          const arr = new Uint8Array(n)
          /* eslint-disable-next-line */
          self.crypto.getRandomValues(arr);
          return [...arr]
        }
      } /* if (typeof window === 'object') */ else {
        this._rand = noRand
      }
    } else {
      try {
        /* eslint-disable-next-line */
        const crypto = require("crypto");
        if (typeof crypto.randomBytes === 'function') {
          this._rand = (n: number) => [...crypto.randomBytes(n)]
        }
      } catch {
        this._rand = noRand
      }
    }
  }

  generate (len: number): number[] {
    return this._rand(len)
  }
}

let ayn: Rand | null = null

/**
 * Generates a sequence of pseudo-random bytes with the given length.
 *
 * @param len - The number of bytes to generate
 *
 * @returns The generated bytes
 *
 * @example
 * import Random from '@bsv/sdk/primitives/Random'
 * const bytes = Random(32) // Produces 32 random bytes
 */
export default (len: number): number[] => {
  if (ayn == null) {
    ayn = new Rand()
  }
  return ayn.generate(len)
}