# Nimbus
# Copyright (c) 2021-2024 Status Research & Development GmbH
# Licensed under either of
#  * Apache License, version 2.0, ([LICENSE-APACHE](LICENSE-APACHE) or
#    http://www.apache.org/licenses/LICENSE-2.0)
#  * MIT license ([LICENSE-MIT](LICENSE-MIT) or
#    http://opensource.org/licenses/MIT)
# at your option. This file may not be copied, modified, or distributed except
# according to those terms.

import
  std/sequtils,
  eth/common

# ------------------------------------------------------------------------------
# Public helpers
# ------------------------------------------------------------------------------

proc startAt*(
    h: openArray[BlockHeader];
    b: openArray[BlockBody];
    start: uint64;
      ): (seq[BlockHeader],seq[BlockBody]) =
  ## Filter out blocks with smaller `blockNumber`
  if start.toBlockNumber <= h[0].blockNumber:
    return (h.toSeq,b.toSeq)
  if start.toBlockNumber <= h[^1].blockNumber:
    # There are at least two headers, find the least acceptable one
    var n = 1
    while h[n].blockNumber < start.toBlockNumber:
      n.inc
    return (h[n ..< h.len], b[n ..< b.len])

proc stopAfter*(
    h: openArray[BlockHeader];
    b: openArray[BlockBody];
    last: uint64;
      ): (seq[BlockHeader],seq[BlockBody]) =
  ## Filter out blocks with larger `blockNumber`
  if h[^1].blockNumber <= last.toBlockNumber:
    return (h.toSeq,b.toSeq)
  if h[0].blockNumber <= last.toBlockNumber:
    # There are at least two headers, find the last acceptable one
    var n = 1
    while h[n].blockNumber <= last.toBlockNumber:
      n.inc
    return (h[0 ..< n], b[0 ..< n])

# ------------------------------------------------------------------------------
# End
# ------------------------------------------------------------------------------