import { createHash, randomBytes } from 'crypto'
import { prisma } from '@/lib/prisma'

const DEFAULT_TTL_MS = 7 * 24 * 60 * 60 * 1000

function hashMaterialShareToken(token: string): string {
  return createHash('sha256').update(token).digest('hex')
}

export function getMaterialShareTokenHash(token: string): string {
  return hashMaterialShareToken(token)
}

export async function createMaterialShareToken(
  materialId: string,
  createdByUserId: string,
  ttlMs = DEFAULT_TTL_MS
): Promise<{ token: string; expiresAt: Date }> {
  const token = randomBytes(32).toString('base64url')
  const expiresAt = new Date(Date.now() + ttlMs)

  await prisma.materialShareToken.create({
    data: {
      tokenHash: hashMaterialShareToken(token),
      materialId,
      createdByUserId,
      expiresAt,
    },
  })

  return { token, expiresAt }
}

export async function findValidMaterialShareToken(token: string, materialId?: string) {
  const normalizedToken = token?.trim()
  if (!normalizedToken) return null

  const now = new Date()
  return prisma.materialShareToken.findFirst({
    where: {
      tokenHash: hashMaterialShareToken(normalizedToken),
      ...(materialId ? { materialId } : {}),
      revokedAt: null,
      expiresAt: { gt: now },
      material: {
        deletedAt: null,
      },
    },
    include: {
      material: true,
    },
  })
}