export function float32ArrayToBuffer(vector: number[]): Buffer {
  const array = Float32Array.from(vector)
  return Buffer.from(array.buffer, array.byteOffset, array.byteLength)
}

export function bufferToFloat32Array(buffer: Buffer): number[] {
  const view = new Float32Array(buffer.buffer, buffer.byteOffset, Math.floor(buffer.byteLength / Float32Array.BYTES_PER_ELEMENT))
  return Array.from(view)
}

export function normalizeVector(vector: number[]): number[] {
  const norm = Math.sqrt(vector.reduce((sum, value) => sum + value * value, 0))
  if (!Number.isFinite(norm) || norm === 0) return vector.map(() => 0)
  return vector.map((value) => value / norm)
}

export function cosineSimilarity(a: number[], b: number[]): number {
  const length = Math.min(a.length, b.length)
  if (length === 0) return 0
  let dot = 0
  let normA = 0
  let normB = 0
  for (let index = 0; index < length; index += 1) {
    const av = a[index] ?? 0
    const bv = b[index] ?? 0
    dot += av * bv
    normA += av * av
    normB += bv * bv
  }
  if (normA === 0 || normB === 0) return 0
  return dot / (Math.sqrt(normA) * Math.sqrt(normB))
}