# beacon_chain
# Copyright (c) 2018-2024 Status Research & Development GmbH
# Licensed and distributed under either of
#   * MIT license (license terms in the root directory or at https://opensource.org/licenses/MIT).
#   * Apache v2 license (license terms in the root directory or at https://www.apache.org/licenses/LICENSE-2.0).
# at your option. This file may not be copied, modified, or distributed except according to those terms.

{.push raises: [].}
{.used.}

import
  # Status libraries
  stew/bitops2,
  eth/common/eth_types as commonEthTypes, eth/common/eth_types_rlp,
  web3/primitives,
  # Beacon chain internals
  ../beacon_chain/spec/[forks, helpers, state_transition],
  ../beacon_chain/spec/datatypes/[bellatrix, capella],
  # Test utilities
  unittest2, mocking/mock_genesis

suite "Spec helpers":
  test "integer_squareroot":
    check:
      integer_squareroot(1'u64) == 1'u64
      integer_squareroot(2'u64) == 1'u64
      integer_squareroot(3'u64) == 1'u64
      integer_squareroot(4'u64) == 2'u64
      integer_squareroot(5'u64) == 2'u64

      # https://github.com/ethereum/consensus-specs/pull/3600
      integer_squareroot(0'u64) == 0'u64
      integer_squareroot(100'u64) == 10'u64
      integer_squareroot(18446744073709551614'u64) == 4294967295'u64
      integer_squareroot(18446744073709551615'u64) == 4294967295'u64

  test "build_proof - BeaconState":
    var
      forked = newClone(initGenesisState())
      cache = StateCache()
      info = ForkedEpochInfo()
    process_slots(
      defaultRuntimeConfig, forked[], Slot(100), cache, info,
      flags = {}).expect("no failure")

    let
      state = forked[].phase0Data.data
      root = state.hash_tree_root()

    func numLeaves(obj: object): GeneralizedIndex =
      nextPow2(typeof(obj).totalSerializedFields.uint64).GeneralizedIndex

    proc process(anchor: object, index: GeneralizedIndex) =
      var i = index
      anchor.enumInstanceSerializedFields(_, fieldVar):
        let depth = log2trunc(i)
        var proof = newSeq[Eth2Digest](depth)
        state.build_proof(i, proof).get
        check:
          hash_tree_root(fieldVar) == hash_tree_root(state, i).get
          is_valid_merkle_branch(hash_tree_root(fieldVar), proof,
                                 depth, get_subtree_index(i), root)
        when fieldVar is object and not (fieldVar is Eth2Digest):
          let
            numChildLeaves = fieldVar.numLeaves
            childDepth = log2trunc(numChildLeaves)
          process(fieldVar, i shl childDepth)
        i += 1
    process(state, state.numLeaves)

  test "hypergeom_cdf":
    # Generated with SciPy's hypergeom.cdf() function
    const tests = [
      (  0,   2,   1,   1, 0.5),
      (  8, 200, 162,   9, 0.85631007588636132),
      (  2,  20,  11,   5, 0.39551083591331271),
      (  2,   5,   4,   3, 0.59999999999999987),
      ( 16, 100,  71,  28, 0.050496322336354399),
      (  1,   5,   2,   2, 0.90000000000000002),
      (  0,   5,   4,   1, 0.20000000000000004),
      ( 27, 200, 110,  54, 0.24032479119039216),
      (  0,  10,   2,   5, 0.22222222222222224),
      (  3,  50,  27,   5, 0.77138514980460271),
      (  2,  50,  24,   8, 0.15067269856977925),
      (  4,  20,  16,   7, 0.10113519091847264),
      ( 13, 500, 408,  15, 0.79686197891279686),
      (  0,   5,   3,   1, 0.40000000000000008),
      (  0,  20,  14,   2, 0.078947368421052627),
      ( 49, 100,  62,  79, 0.6077614986362827),
      (  2,  10,   3,   6, 0.83333333333333337),
      (  0,  50,  31,   2, 0.13959183673469389),
      (  2,   5,   4,   3, 0.59999999999999987),
      (  4,  50,  21,   8, 0.81380887468704521),
      (  0,  10,   7,   2, 0.066666666666666652),
      (  0,  10,   1,   4, 0.59999999999999987),
      (  0,  20,   4,   2, 0.63157894736842102),
      (  0,   3,   2,   1, 0.33333333333333331),
      ( 39, 500, 427,  51, 0.05047757656076568),
      (  2, 100,   6,  21, 0.89490672557682871),
      (  5,  20,  11,   9, 0.68904501071683733),
      (  0,   2,   1,   1, 0.5),
      (  0,   3,   1,   1, 0.66666666666666674),
      ( 14,  50,  27,  30, 0.16250719969887772),
      (  0,   5,   4,   1, 0.20000000000000004),
      (  0,   5,   4,   1, 0.20000000000000004),
      (  2,  10,   8,   4, 0.13333333333333333),
      (  1,   5,   3,   2, 0.69999999999999996),
      ( 25, 100,  77,  31, 0.79699287800204943),
      (  0,   3,   2,   1, 0.33333333333333331),
      (  7,  20,  15,   8, 0.94891640866873062),
      (  3,  50,  26,   7, 0.45339412360688952),
      (  1,  10,   8,   2, 0.37777777777777771),
      ( 40, 200,  61, 134, 0.4491054454532335),
      (  1,   5,   2,   4, 0.40000000000000008),
      (  0,  10,   6,   1, 0.39999999999999991),
      (  1,  50,  10,  13, 0.19134773839560071),
      (  0,   2,   1,   1, 0.5),
      (  1,  20,   5,   2, 0.94736842105263153),
      (  7,  50,  12,  30, 0.57532691212157849),
      (  0,   3,   1,   1, 0.66666666666666674),
      (  6,  10,   7,   9, 0.69999999999999996),
      (  0,  20,   2,   1, 0.90000000000000002),
      (  2,  10,   5,   3, 0.91666666666666663),
      (  0,  10,   8,   1, 0.19999999999999998),
      (258, 500, 372, 347, 0.53219975096883698),
      (  1,   3,   2,   2, 0.66666666666666674),
      ( 45, 200, 129,  68, 0.69415691010446789),
      (  1,  10,   8,   2, 0.37777777777777771),
      (  0,  10,   2,   1, 0.80000000000000004),
      (  1,  10,   4,   5, 0.26190476190476192),
      (  3,  50,  36,   4, 0.74422492401215801),
      (  0,  20,   6,   1, 0.69999999999999996),
      (  0,   5,   2,   3, 0.10000000000000002),
      (  1, 200,  47,   9, 0.33197417194852796),
      ( 20,  50,  32,  30, 0.78323921453982637),
      ( 16,  50,  21,  34, 0.9149336897131396),
      ( 17,  50,  38,  22, 0.69599001425795692),
      (  0,   5,   2,   3, 0.10000000000000002),
      (  1,   5,   3,   2, 0.69999999999999996),
      (  0,  10,   9,   1, 0.10000000000000001),
      (  0,   5,   2,   3, 0.10000000000000002),
      (  2,  10,   5,   6, 0.26190476190476192),
      (  0,   5,   2,   1, 0.59999999999999987),
      (  7,  20,  16,   9, 0.62538699690402466),
      (  1, 100,  27,   2, 0.92909090909090908),
      ( 27, 100,  58,  50, 0.271780848715515),
      ( 47, 100,  96,  51, 0.063730084348641039),
      (  1,  20,   6,   2, 0.92105263157894735),
      (  1,  10,   6,   2, 0.66666666666666674),
      (  0,   2,   1,   1, 0.5),
      (  0,  20,  11,   1, 0.45000000000000001),
      (  0,   3,   1,   1, 0.66666666666666674),
      (  0,   2,   1,   1, 0.5),
      (  0,  10,   1,   7, 0.29999999999999999),
      (  0,   2,   1,   1, 0.5),
      (  0, 100,  36,   1, 0.64000000000000001),
      (  1, 100,  68,   2, 0.53979797979797983),
      ( 13, 200,  79,  29, 0.80029860188814683),
      (  0,  10,   5,   1, 0.49999999999999994),
      (  0,   3,   2,   1, 0.33333333333333331),
      ( 13, 100,  64,  21, 0.5065368728909565),
      (  1,  10,   6,   4, 0.11904761904761905),
      (  0,   2,   1,   1, 0.5),
      (  0,   5,   1,   2, 0.59999999999999987),
      (  0,   2,   1,   1, 0.5),
      (  1,   5,   4,   2, 0.40000000000000008),
      ( 14,  50,  41,  17, 0.65850372332742224),
      (  0,   2,   1,   1, 0.5),
      (  0,   3,   1,   1, 0.66666666666666674),
      (  1, 100,   2,  62, 0.61797979797979785),
      (  0,   2,   1,   1, 0.5),
      (  0,   2,   1,   1, 0.5),
      ( 12, 500, 312,  16, 0.91020698917397613),
      (  0,  20,   2,   6, 0.47894736842105257),
      (  0,   3,   2,   1, 0.33333333333333331),
      (  1,  10,   3,   4, 0.66666666666666674),
      (  0,   3,   1,   1, 0.66666666666666674),
      (  0,   3,   2,   1, 0.33333333333333331),
      (  6,  50,  20,  14, 0.72026241648862666),
      (  3,  20,  14,   6, 0.22523219814241485),
      (  0,   2,   1,   1, 0.5),
      (  4, 100,  72,   7, 0.30429108474790234),
      (  0,   5,   1,   2, 0.59999999999999987),
      (  0,  10,   4,   1, 0.59999999999999998),
      (  1,   3,   2,   2, 0.66666666666666674),
      (  0,   3,   1,   1, 0.66666666666666674),
      ( 22,  50,  46,  24, 0.66413373860182379),
      (  1,   5,   2,   4, 0.40000000000000008),
      ( 62, 100,  80,  79, 0.3457586020522983),
      (  0,   3,   2,   1, 0.33333333333333331),
      (  0,  10,   2,   7, 0.066666666666666666),
      (  0,   2,   1,   1, 0.5),
      (  0,   5,   2,   1, 0.59999999999999987),
      ( 42, 200, 145,  57, 0.65622325663713577),
      (  1,  20,  12,   3, 0.34385964912280703),
      (  0,   2,   1,   1, 0.5),
      (  2,  10,   4,   7, 0.33333333333333331),
      (  1,   5,   3,   2, 0.69999999999999996),
      (  0,  10,   6,   2, 0.1333333333333333),
      (  2,  10,   6,   5, 0.26190476190476192),
      (  0,   5,   2,   1, 0.59999999999999987),
      (  1,   3,   2,   2, 0.66666666666666674),
      (  0,  50,  25,   2, 0.24489795918367349),
      (  0,  50,  39,   1, 0.22),
      (  2,   5,   3,   3, 0.90000000000000002),
      (  9,  50,  46,  10, 0.60316977854971765),
      (  0,   5,   2,   1, 0.59999999999999987),
      ( 72, 500, 324, 112, 0.49074275180525029),
      (  0,  50,   9,   7, 0.22507959200836167),
      (  0,   5,   2,   2, 0.30000000000000004),
      ( 17, 100,  35,  60, 0.067474411926413541),
      ( 15, 100,  83,  17, 0.83718038506483827),
      (  0,  10,   7,   1, 0.29999999999999999),
      ( 28, 200,  87,  77, 0.071226044946921765),
      (154, 500, 361, 212, 0.61327756805578304),
      (  1,  10,   2,   3, 0.93333333333333335),
      (  0,  10,   4,   4, 0.071428571428571425),
      (  0,   5,   1,   1, 0.79999999999999993),
      (  2,   5,   3,   4, 0.59999999999999987),
      (  0,  10,   4,   1, 0.59999999999999998),
      (  0,   3,   2,   1, 0.33333333333333331),
      (  0,  10,   3,   1, 0.69999999999999996),
      (  0,  50,  10,   1, 0.80000000000000004),
      (  0,   2,   1,   1, 0.5),
      (  0,  10,   1,   3, 0.69999999999999996),
      (  2,  20,  12,   4, 0.53457172342621262),
      (  0,   5,   4,   1, 0.20000000000000004),
      (  4,  20,   9,   7, 0.89821981424148611),
      (  2, 200, 188,   3, 0.17021775544388609),
      (132, 500, 298, 215, 0.78880271135040059),
      (  2,   5,   4,   3, 0.59999999999999987),
      (  0,   2,   1,   1, 0.5),
      (  2,  10,   6,   5, 0.26190476190476192),
      (  0,   3,   1,   1, 0.66666666666666674),
      (156, 200, 128, 174, 1),
      (  1,  20,   6,   4, 0.65737874097007221),
      (  0,   5,   0,   0, 1),
      (488, 500, 198, 500, 1),
      (143, 500,   8, 371, 1),
      (  2,  10,   6,   5, 0.26190476190476192),
      (  1,   5,   2,   4, 0.40000000000000008),
      (  0,   3,   2,   0, 1),
      ( 12,  50,   7,  17, 1),
      (129, 200,  43, 133, 1),
      (  0,   5,   3,   0, 1),
      (  0,   2,   1,   1, 0.5),
      (  5,  20,  20,  17, 0),
      (  4,  10,   4,   8, 1),
      ( 46, 500, 478,  58, 5.1715118817799218e-07),
      (  0,   3,   2,   3, 0),
      (  0,   3,   1,   1, 0.66666666666666674),
      ( 76, 500,   0, 120, 1),
      (  1, 100,  41,  12, 0.011989696504564528),
    ]
    for (k, population, successes, draws, val) in tests:
      check: abs(hypergeom_cdf(k, population, successes, draws) - val) < 1e-11