import { address, getAddressEncoder, type Address, type ProgramDerivedAddress } from '@solana/kit'
import { findListingAccountPda, findOrderAccountPda } from './generated/solisting/src/generated/index'

const PROGRAM_ADDRESS = address('9uF64swnFqo34oFJtv8Qx9JDyXXJz73eDFF4cKRBfQBZ')

export async function findListingPda(
  seller: Address,
  listingId: bigint,
): Promise<ProgramDerivedAddress> {
  return findListingAccountPda({ seller, listingId }, { programAddress: PROGRAM_ADDRESS })
}

export async function findOrderPda(
  listingAccount: Address,
  buyer: Address,
  orderId: bigint,
): Promise<ProgramDerivedAddress> {
  return findOrderAccountPda({ listingAccount, buyer, orderId }, { programAddress: PROGRAM_ADDRESS })
}

/**
 * Replicates the program's escrow_id derivation:
 *   u64::from_le_bytes(order_pda.to_bytes()[0..8])
 * Must match exactly — used when building create_order instructions.
 */
export function deriveEscrowId(orderPda: Address): bigint {
  const bytes = getAddressEncoder().encode(orderPda) // 32-byte Uint8Array
  const view = new DataView(bytes.buffer, bytes.byteOffset, bytes.byteLength)
  return view.getBigUint64(0, true) // little-endian, first 8 bytes
}