text: import collections
  import logging
  from typing import Dict, List, Optional, Set, Tuple, Union, Callable
  
  from blspy import AugSchemeMPL, G1Element
  from chiabip158 import PyBIP158
  from clvm.casts import int_from_bytes
  
  from wheat.consensus.block_record import BlockRecord
  from wheat.consensus.block_rewards import calculate_base_farmer_reward, calculate_pool_reward
  from wheat.consensus.block_root_validation import validate_block_merkle_roots
  from wheat.full_node.mempool_check_conditions import mempool_check_conditions_dict
  from wheat.consensus.blockchain_interface import BlockchainInterface
  from wheat.consensus.coinbase import create_farmer_coin, create_pool_coin
  from wheat.consensus.constants import ConsensusConstants
  from wheat.consensus.cost_calculator import NPCResult, calculate_cost_of_program
  from wheat.consensus.find_fork_point import find_fork_point_in_chain
  from wheat.full_node.block_store import BlockStore
  from wheat.full_node.coin_store import CoinStore
  from wheat.full_node.mempool_check_conditions import get_name_puzzle_conditions
  from wheat.types.blockchain_format.coin import Coin
  from wheat.types.blockchain_format.sized_bytes import bytes32
  from wheat.types.coin_record import CoinRecord
  from wheat.types.condition_opcodes import ConditionOpcode
  from wheat.types.condition_with_args import ConditionWithArgs
  from wheat.types.full_block import FullBlock
  from wheat.types.generator_types import BlockGenerator
  from wheat.types.name_puzzle_condition import NPC
  from wheat.types.unfinished_block import UnfinishedBlock
  from wheat.util.condition_tools import (
      pkm_pairs_for_conditions_dict,
      coin_announcements_names_for_npc,
      puzzle_announcements_names_for_npc,
  )
  from wheat.util.errors import Err
  from wheat.util.generator_tools import (
      additions_for_npc,
      tx_removals_and_additions,
  )
  from wheat.util.hash import std_hash
  from wheat.util.ints import uint32, uint64, uint128
  
  log = logging.getLogger(__name__)
  
  
  async def validate_block_body(
      constants: ConsensusConstants,
      blocks: BlockchainInterface,
      block_store: BlockStore,
      coin_store: CoinStore,
      peak: Optional[BlockRecord],
      block: Union[FullBlock, UnfinishedBlock],
      height: uint32,
      npc_result: Optional[NPCResult],
      fork_point_with_peak: Optional[uint32],
      get_block_generator: Callable,
  ) -> Tuple[Optional[Err], Optional[NPCResult]]:
      """
      This assumes the header block has been completely validated.
      Validates the transactions and body of the block. Returns None for the first value if everything
      validates correctly, or an Err if something does not validate. For the second value, returns a CostResult
      only if validation succeeded, and there are transactions. In other cases it returns None. The NPC result is
      the result of running the generator with the previous generators refs. It is only present for transaction
      blocks which have spent coins.
      """
      if isinstance(block, FullBlock):
          assert height == block.height
      prev_transaction_block_height: uint32 = uint32(0)
  
      # 1. For non transaction-blocs: foliage block, transaction filter, transactions info, and generator must
      # be empty. If it is a block but not a transaction block, there is no body to validate. Check that all fields are
      # None
      if block.foliage.foliage_transaction_block_hash is None:
          if (
              block.foliage_transaction_block is not None
              or block.transactions_info is not None
              or block.transactions_generator is not None
          ):
              return Err.NOT_BLOCK_BUT_HAS_DATA, None
  
          prev_tb: BlockRecord = blocks.block_record(block.prev_header_hash)
          while not prev_tb.is_transaction_block:
              prev_tb = blocks.block_record(prev_tb.prev_hash)
          assert prev_tb.timestamp is not None
          if (
              prev_tb.timestamp > constants.INITIAL_FREEZE_END_TIMESTAMP
              and len(block.transactions_generator_ref_list) > 0
          ):
              return Err.NOT_BLOCK_BUT_HAS_DATA, None
  
          return None, None  # This means the block is valid
  
      # All checks below this point correspond to transaction blocks
      # 2. For blocks, foliage block, transactions info must not be empty
      if block.foliage_transaction_block is None or block.transactions_info is None:
          return Err.IS_TRANSACTION_BLOCK_BUT_NO_DATA, None
      assert block.foliage_transaction_block is not None
  
      # keeps track of the reward coins that need to be incorporated
      expected_reward_coins: Set[Coin] = set()
  
      # 3. The transaction info hash in the Foliage block must match the transaction info
      if block.foliage_transaction_block.transactions_info_hash != std_hash(block.transactions_info):
          return Err.INVALID_TRANSACTIONS_INFO_HASH, None
  
      # 4. The foliage block hash in the foliage block must match the foliage block
      if block.foliage.foliage_transaction_block_hash != std_hash(block.foliage_transaction_block):
          return Err.INVALID_FOLIAGE_BLOCK_HASH, None
  
      # 5. The reward claims must be valid for the previous blocks, and current block fees
      # If height == 0, expected_reward_coins will be left empty
      if height > 0:
          # Add reward claims for all blocks from the prev prev block, until the prev block (including the latter)
          prev_transaction_block = blocks.block_record(block.foliage_transaction_block.prev_transaction_block_hash)
          prev_transaction_block_height = prev_transaction_block.height
          assert prev_transaction_block.fees is not None
          pool_coin = create_pool_coin(
              prev_transaction_block_height,
              prev_transaction_block.pool_puzzle_hash,
              calculate_pool_reward(prev_transaction_block.height),
              constants.GENESIS_CHALLENGE,
          )
          farmer_coin = create_farmer_coin(
              prev_transaction_block_height,
              prev_transaction_block.farmer_puzzle_hash,
              uint64(calculate_base_farmer_reward(prev_transaction_block.height) + prev_transaction_block.fees),
              constants.GENESIS_CHALLENGE,
          )
          # Adds the previous block
          expected_reward_coins.add(pool_coin)
          expected_reward_coins.add(farmer_coin)
  
          # For the second block in the chain, don't go back further
          if prev_transaction_block.height > 0:
              curr_b = blocks.block_record(prev_transaction_block.prev_hash)
              while not curr_b.is_transaction_block:
                  expected_reward_coins.add(
                      create_pool_coin(
                          curr_b.height,
                          curr_b.pool_puzzle_hash,
                          calculate_pool_reward(curr_b.height),
                          constants.GENESIS_CHALLENGE,
                      )
                  )
                  expected_reward_coins.add(
                      create_farmer_coin(
                          curr_b.height,
                          curr_b.farmer_puzzle_hash,
                          calculate_base_farmer_reward(curr_b.height),
                          constants.GENESIS_CHALLENGE,
                      )
                  )
                  curr_b = blocks.block_record(curr_b.prev_hash)
  
      if set(block.transactions_info.reward_claims_incorporated) != expected_reward_coins:
          return Err.INVALID_REWARD_COINS, None
  
      if block.foliage_transaction_block.timestamp > constants.INITIAL_FREEZE_END_TIMESTAMP:
          if len(block.transactions_info.reward_claims_incorporated) != len(expected_reward_coins):
              # No duplicates, after transaction freeze period. Duplicates cause no issues because we filter them out
              # anyway.
              return Err.INVALID_REWARD_COINS, None
  
      removals: List[bytes32] = []
      coinbase_additions: List[Coin] = list(expected_reward_coins)
      additions: List[Coin] = []
      coin_announcement_names: Set[bytes32] = set()
      puzzle_announcement_names: Set[bytes32] = set()
      npc_list: List[NPC] = []
      removals_puzzle_dic: Dict[bytes32, bytes32] = {}
      cost: uint64 = uint64(0)
  
      # We check in header validation that timestamp is not more that 10 minutes into the future
      if (
          block.foliage_transaction_block.timestamp <= constants.INITIAL_FREEZE_END_TIMESTAMP
          and block.transactions_generator is not None
      ):
          # 6. No transactions before INITIAL_TRANSACTION_FREEZE timestamp
          return Err.INITIAL_TRANSACTION_FREEZE, None
      else:
          # 7a. The generator root must be the hash of the serialized bytes of
          #     the generator for this block (or zeroes if no generator)
          if block.transactions_generator is not None:
              if std_hash(bytes(block.transactions_generator)) != block.transactions_info.generator_root:
                  return Err.INVALID_TRANSACTIONS_GENERATOR_HASH, None
          else:
              if block.transactions_info.generator_root != bytes([0] * 32):
                  return Err.INVALID_TRANSACTIONS_GENERATOR_HASH, None
  
          # 8a. The generator_ref_list must be the hash of the serialized bytes of
          #     the generator ref list for this block (or 'one' bytes [0x01] if no generator)
          # 8b. The generator ref list length must be less than or equal to MAX_GENERATOR_REF_LIST_SIZE entries
          # 8c. The generator ref list must not point to a height >= this block's height
          if block.transactions_generator_ref_list in (None, []):
              if block.transactions_info.generator_refs_root != bytes([1] * 32):
                  return Err.INVALID_TRANSACTIONS_GENERATOR_REFS_ROOT, None
          else:
              # If we have a generator reference list, we must have a generator
              if block.transactions_generator is None:
                  return Err.INVALID_TRANSACTIONS_GENERATOR_REFS_ROOT, None
  
              # The generator_refs_root must be the hash of the concatenation of the List[uint32]
              generator_refs_hash = std_hash(b"".join([bytes(i) for i in block.transactions_generator_ref_list]))
              if block.transactions_info.generator_refs_root != generator_refs_hash:
                  return Err.INVALID_TRANSACTIONS_GENERATOR_REFS_ROOT, None
              if len(block.transactions_generator_ref_list) > constants.MAX_GENERATOR_REF_LIST_SIZE:
                  return Err.TOO_MANY_GENERATOR_REFS, None
              if any([index >= height for index in block.transactions_generator_ref_list]):
                  return Err.FUTURE_GENERATOR_REFS, None
  
          if block.transactions_generator is not None:
              # Get List of names removed, puzzles hashes for removed coins and conditions created
  
              assert npc_result is not None
              cost = calculate_cost_of_program(block.transactions_generator, npc_result, constants.COST_PER_BYTE)
              npc_list = npc_result.npc_list
  
              # 7. Check that cost <= MAX_BLOCK_COST_CLVM
              log.debug(
                  f"Cost: {cost} max: {constants.MAX_BLOCK_COST_CLVM} "
                  f"percent full: {round(100 * (cost / constants.MAX_BLOCK_COST_CLVM), 2)}%"
              )
              if cost > constants.MAX_BLOCK_COST_CLVM:
                  return Err.BLOCK_COST_EXCEEDS_MAX, None
  
              # 8. The CLVM program must not return any errors
              if npc_result.error is not None:
                  return Err(npc_result.error), None
  
              for npc in npc_list:
                  removals.append(npc.coin_name)
                  removals_puzzle_dic[npc.coin_name] = npc.puzzle_hash
  
              additions = additions_for_npc(npc_list)
              coin_announcement_names = coin_announcements_names_for_npc(npc_list)
              puzzle_announcement_names = puzzle_announcements_names_for_npc(npc_list)
          else:
              assert npc_result is None
  
          # 9. Check that the correct cost is in the transactions info
          if block.transactions_info.cost != cost:
              return Err.INVALID_BLOCK_COST, None
  
          additions_dic: Dict[bytes32, Coin] = {}
          # 10. Check additions for max coin amount
          # Be careful to check for 64 bit overflows in other languages. This is the max 64 bit unsigned integer
          # We will not even reach here because Coins do type checking (uint64)
          for coin in additions + coinbase_additions:
              additions_dic[coin.name()] = coin
              if coin.amount < 0:
                  return Err.COIN_AMOUNT_NEGATIVE, None
  
              if coin.amount > constants.MAX_COIN_AMOUNT:
                  return Err.COIN_AMOUNT_EXCEEDS_MAXIMUM, None
  
          # 11. Validate addition and removal roots
          root_error = validate_block_merkle_roots(
              block.foliage_transaction_block.additions_root,
              block.foliage_transaction_block.removals_root,
              additions + coinbase_additions,
              removals,
          )
          if root_error:
              return root_error, None
  
          # 12. The additions and removals must result in the correct filter
          byte_array_tx: List[bytes32] = []
  
          for coin in additions + coinbase_additions:
              byte_array_tx.append(bytearray(coin.puzzle_hash))
          for coin_name in removals:
              byte_array_tx.append(bytearray(coin_name))
  
          bip158: PyBIP158 = PyBIP158(byte_array_tx)
          encoded_filter = bytes(bip158.GetEncoded())
          filter_hash = std_hash(encoded_filter)
  
          if filter_hash != block.foliage_transaction_block.filter_hash:
              return Err.INVALID_TRANSACTIONS_FILTER_HASH, None
  
          # 13. Check for duplicate outputs in additions
          addition_counter = collections.Counter(_.name() for _ in additions + coinbase_additions)
          for k, v in addition_counter.items():
              if v > 1:
                  return Err.DUPLICATE_OUTPUT, None
  
          # 14. Check for duplicate spends inside block
          removal_counter = collections.Counter(removals)
          for k, v in removal_counter.items():
              if v > 1:
                  return Err.DOUBLE_SPEND, None
  
          # 15. Check if removals exist and were not previously spent. (unspent_db + diff_store + this_block)
          # The fork point is the last block in common between the peak chain and the chain of `block`
          if peak is None or height == 0:
              fork_h: int = -1
          elif fork_point_with_peak is not None:
              fork_h = fork_point_with_peak
          else:
              fork_h = find_fork_point_in_chain(blocks, peak, blocks.block_record(block.prev_header_hash))
  
          # Get additions and removals since (after) fork_h but not including this block
          # The values include: the coin that was added, the height of the block in which it was confirmed, and the
          # timestamp of the block in which it was confirmed
          additions_since_fork: Dict[bytes32, Tuple[Coin, uint32, uint64]] = {}  # This includes coinbase additions
          removals_since_fork: Set[bytes32] = set()
  
          # For height 0, there are no additions and removals before this block, so we can skip
          if height > 0:
              # First, get all the blocks in the fork > fork_h, < block.height
              prev_block: Optional[FullBlock] = await block_store.get_full_block(block.prev_header_hash)
              reorg_blocks: Dict[uint32, FullBlock] = {}
              curr: Optional[FullBlock] = prev_block
              assert curr is not None
              while curr.height > fork_h:
                  if curr.height == 0:
                      break
                  curr = await block_store.get_full_block(curr.prev_header_hash)
                  assert curr is not None
                  reorg_blocks[curr.height] = curr
              if fork_h != -1:
                  assert len(reorg_blocks) == height - fork_h - 1
  
              curr = prev_block
              assert curr is not None
              while curr.height > fork_h:
                  # Coin store doesn't contain coins from fork, we have to run generator for each block in fork
                  if curr.transactions_generator is not None:
                      # These blocks are in the past and therefore assumed to be valid, so get_block_generator won't raise
                      curr_block_generator: Optional[BlockGenerator] = await get_block_generator(curr)
                      assert curr_block_generator is not None and curr.transactions_info is not None
                      curr_npc_result = get_name_puzzle_conditions(
                          curr_block_generator,
                          min(constants.MAX_BLOCK_COST_CLVM, curr.transactions_info.cost),
                          cost_per_byte=constants.COST_PER_BYTE,
                          safe_mode=False,
                      )
                      removals_in_curr, additions_in_curr = tx_removals_and_additions(curr_npc_result.npc_list)
                  else:
                      removals_in_curr = []
                      additions_in_curr = []
  
                  for c_name in removals_in_curr:
                      assert c_name not in removals_since_fork
                      removals_since_fork.add(c_name)
                  for c in additions_in_curr:
                      assert c.name() not in additions_since_fork
                      assert curr.foliage_transaction_block is not None
                      additions_since_fork[c.name()] = (c, curr.height, curr.foliage_transaction_block.timestamp)
  
                  for coinbase_coin in curr.get_included_reward_coins():
                      assert coinbase_coin.name() not in additions_since_fork
                      assert curr.foliage_transaction_block is not None
                      additions_since_fork[coinbase_coin.name()] = (
                          coinbase_coin,
                          curr.height,
                          curr.foliage_transaction_block.timestamp,
                      )
                  if curr.height == 0:
                      break
                  curr = reorg_blocks[curr.height - 1]
                  assert curr is not None
  
          removal_coin_records: Dict[bytes32, CoinRecord] = {}
          for rem in removals:
              if rem in additions_dic:
                  # Ephemeral coin
                  rem_coin: Coin = additions_dic[rem]
                  new_unspent: CoinRecord = CoinRecord(
                      rem_coin,
                      height,
                      height,
                      True,
                      False,
                      block.foliage_transaction_block.timestamp,
                  )
                  removal_coin_records[new_unspent.name] = new_unspent
              else:
                  unspent = await coin_store.get_coin_record(rem)
                  if unspent is not None and unspent.confirmed_block_index <= fork_h:
                      # Spending something in the current chain, confirmed before fork
                      # (We ignore all coins confirmed after fork)
                      if unspent.spent == 1 and unspent.spent_block_index <= fork_h:
                          # Check for coins spent in an ancestor block
                          return Err.DOUBLE_SPEND, None
                      removal_coin_records[unspent.name] = unspent
                  else:
                      # This coin is not in the current heaviest chain, so it must be in the fork
                      if rem not in additions_since_fork:
                          # Check for spending a coin that does not exist in this fork
                          log.error(f"Err.UNKNOWN_UNSPENT: COIN ID: {rem} NPC RESULT: {npc_result}")
                          return Err.UNKNOWN_UNSPENT, None
                      new_coin, confirmed_height, confirmed_timestamp = additions_since_fork[rem]
                      new_coin_record: CoinRecord = CoinRecord(
                          new_coin,
                          confirmed_height,
                          uint32(0),
                          False,
                          False,
                          confirmed_timestamp,
                      )
                      removal_coin_records[new_coin_record.name] = new_coin_record
  
                  # This check applies to both coins created before fork (pulled from coin_store),
                  # and coins created after fork (additions_since_fork)
                  if rem in removals_since_fork:
                      # This coin was spent in the fork
                      return Err.DOUBLE_SPEND_IN_FORK, None
  
          removed = 0
          for unspent in removal_coin_records.values():
              removed += unspent.coin.amount
  
          added = 0
          for coin in additions:
              added += coin.amount
  
          # 16. Check that the total coin amount for added is <= removed
          if removed < added:
              return Err.MINTING_COIN, None
  
          fees = removed - added
          assert fees >= 0
          assert_fee_sum: uint128 = uint128(0)
  
          for npc in npc_list:
              if ConditionOpcode.RESERVE_FEE in npc.condition_dict:
                  fee_list: List[ConditionWithArgs] = npc.condition_dict[ConditionOpcode.RESERVE_FEE]
                  for cvp in fee_list:
                      fee = int_from_bytes(cvp.vars[0])
                      if fee < 0:
                          return Err.RESERVE_FEE_CONDITION_FAILED, None
                      assert_fee_sum = uint128(assert_fee_sum + fee)
  
          # 17. Check that the assert fee sum <= fees, and that each reserved fee is non-negative
          if fees < assert_fee_sum:
              return Err.RESERVE_FEE_CONDITION_FAILED, None
  
          # 18. Check that the fee amount + farmer reward < maximum coin amount
          if fees + calculate_base_farmer_reward(height) > constants.MAX_COIN_AMOUNT:
              return Err.COIN_AMOUNT_EXCEEDS_MAXIMUM, None
  
          # 19. Check that the computed fees are equal to the fees in the block header
          if block.transactions_info.fees != fees:
              return Err.INVALID_BLOCK_FEE_AMOUNT, None
  
          # 20. Verify that removed coin puzzle_hashes match with calculated puzzle_hashes
          for unspent in removal_coin_records.values():
              if unspent.coin.puzzle_hash != removals_puzzle_dic[unspent.name]:
                  return Err.WRONG_PUZZLE_HASH, None
  
          # 21. Verify conditions
          # create hash_key list for aggsig check
          pairs_pks: List[G1Element] = []
          pairs_msgs: List[bytes] = []
          for npc in npc_list:
              assert height is not None
              unspent = removal_coin_records[npc.coin_name]
              error = mempool_check_conditions_dict(
                  unspent,
                  coin_announcement_names,
                  puzzle_announcement_names,
                  npc.condition_dict,
                  prev_transaction_block_height,
                  block.foliage_transaction_block.timestamp,
              )
              if error:
                  return error, None
              for pk, m in pkm_pairs_for_conditions_dict(
                  npc.condition_dict, npc.coin_name, constants.AGG_SIG_ME_ADDITIONAL_DATA
              ):
                  pairs_pks.append(pk)
                  pairs_msgs.append(m)
  
          # 22. Verify aggregated signature
          # TODO: move this to pre_validate_blocks_multiprocessing so we can sync faster
          if not block.transactions_info.aggregated_signature:
              return Err.BAD_AGGREGATE_SIGNATURE, None
  
          # noinspection PyTypeChecker
          if not AugSchemeMPL.aggregate_verify(pairs_pks, pairs_msgs, block.transactions_info.aggregated_signature):
              return Err.BAD_AGGREGATE_SIGNATURE, None
  
          return None, npc_result
  