import Base
import ./sol.bend as S

# SPL Token account words (165-byte layout, little-endian u32 view):
#   0..7   mint
#   8..15  owner
#   16..17 amount (full SPL u64)
# Mint decimals live at byte 44 (low byte of word 11).
#
# TokenkegQfeZyiNwAJbNbGKPFXCWuBvf9Ss623VQ5DA

def token_id() -> S.Pubkey:
  S.Pk{3791052038, 2476828119, 1189202905, 2893671374, 3984962588, 2436324191, 2247461946, 2835414910}

def TOKEN_WORDS() -> Nat:
  42n

def token_mint(data: List<&2, U32>) -> S.Pubkey:
  S.read_pk(data, 0n)

def token_owner(data: List<&2, U32>) -> S.Pubkey:
  S.read_pk(data, 8n)

def token_amount(data: List<&2, U32>) -> S.U64:
  S.load_u64(data, 16n)

def token_set_amount(data: List<&2, U32>, amt: S.U64) -> List<&2, U32>:
  S.store_u64(data, 16n, amt)

def mint_decimals(data: List<&2, U32>) -> U32:
  U32.and(S.word_at(data, 11n), 255)

def acc_is_token(+a: S.Account) -> Bool:
  S.Pubkey.eq(S.acc_owner(a), token_id())

def token_same_mint(+a: List<&2, U32>, +b: List<&2, U32>) -> Bool:
  S.Pubkey.eq(token_mint(a), token_mint(b))

def token_owned(+data: List<&2, U32>, +owner: S.Pubkey) -> Bool:
  S.Pubkey.eq(token_owner(data), owner)