# encoding: ascii-8bit

require_relative 'spec_helper.rb'
require 'bitcoin/script'

include Bitcoin
include Bitcoin::Builder

describe 'Bitcoin::Dogecoin' do
  it 'validate dogecoin-address' do

    Bitcoin::network = :dogecoin_testnet

    # Testnet address
    Bitcoin.valid_address?("nUtMFED5VRg5xuj9QCrNFt9mVPFDXo7TTE").should == true
    # Livenet address
    Bitcoin.valid_address?("DSpgzjPyfQB6ZzeSbMWpaZiTTxGf2oBCs4").should == false
    # Broken address
    Bitcoin.valid_address?("DRjyUS2uuieEPkhZNdQz8hE5YycxVEqSXA").should == false

    Bitcoin::network = :dogecoin

    # Testnet address
    Bitcoin.valid_address?("nUtMFED5VRg5xuj9QCrNFt9mVPFDXo7TTE").should == false
    # Livenet address
    Bitcoin.valid_address?("DSpgzjPyfQB6ZzeSbMWpaZiTTxGf2oBCs4").should == true
    # Broken address
    Bitcoin.valid_address?("DRjyUS2uuieEPkhZNdQz8hE5YycxVEqSXA").should == false
  end

  it 'should calculate retarget difficulty' do
    Bitcoin::network = :dogecoin

    prev_height = 239
    prev_block_time = 1386475638 # Block 239
    prev_block_bits = 0x1e0ffff0
    last_retarget_time = 1386474927 # Block 1
    new_difficulty = Bitcoin.block_new_target(prev_height, prev_block_time, prev_block_bits, last_retarget_time)
    new_difficulty.to_s(16).should == 0x1e00ffff.to_s(16)

    prev_height = 479
    prev_block_time = 1386475840
    prev_block_bits = 0x1e0fffff
    last_retarget_time = 1386475638 # Block 239
    new_difficulty = Bitcoin.block_new_target(prev_height, prev_block_time, prev_block_bits, last_retarget_time)
    new_difficulty.to_s(16).should == 0x1e00ffff.to_s(16)

    prev_height = 9_599
    prev_block_time = 1386954113
    prev_block_bits = 0x1c1a1206
    last_retarget_time = 1386942008 # Block 9359
    new_difficulty = Bitcoin.block_new_target(prev_height, prev_block_time, prev_block_bits, last_retarget_time)
    new_difficulty.to_s(16).should == 0x1c15ea59.to_s(16)

    # First hard-fork at 145,000, which applies to block 145,001 onwards
    prev_height = 145_000
    prev_block_time = 1395094679
    prev_block_bits = 0x1b499dfd
    last_retarget_time = 1395094427
    new_difficulty = Bitcoin.block_new_target(prev_height, prev_block_time, prev_block_bits, last_retarget_time)
    new_difficulty.to_s(16).should == 0x1b671062.to_s(16)

    # Test case for correct rounding of modulated time - by default C++ and Ruby do not
    # necessarily round identically
    prev_height = 145_001
    prev_block_time = 1395094727
    prev_block_bits = 0x1b671062
    last_retarget_time = 1395094679
    new_difficulty = Bitcoin.block_new_target(prev_height, prev_block_time, prev_block_bits, last_retarget_time)
    new_difficulty.to_s(16).should == 0x1b6558a4.to_s(16)

    # Test the second hard-fork at 371,337 as well
    prev_height = 371336
    prev_block_time = 1410464569
    prev_block_bits = 0x1b2fdf75
    last_retarget_time = 1410464445
    new_difficulty = Bitcoin.block_new_target(prev_height, prev_block_time, prev_block_bits, last_retarget_time)
    new_difficulty.to_s(16).should == 0x1b364184.to_s(16)

    prev_height = 408_596
    prev_block_time = 1412800112
    prev_block_bits = 0x1b033d8b
    last_retarget_time = 1412799989 # Block 408,595
    new_difficulty = Bitcoin.block_new_target(prev_height, prev_block_time, prev_block_bits, last_retarget_time)
    new_difficulty.to_s(16).should == 0x1b039e52.to_s(16)
  end

  it 'should calculate reward upper bounds' do
    Bitcoin::network = :dogecoin

    Bitcoin.block_creation_reward(99000).should == 1000000 * COIN # Note this is the maximum possible, not actual reward
    Bitcoin.block_creation_reward(144999).should == 500000 * COIN
    Bitcoin.block_creation_reward(145000).should == 250000 * COIN # Hard-forked to remove random rewards
    Bitcoin.block_creation_reward(199999).should == 250000 * COIN
    Bitcoin.block_creation_reward(299999).should == 125000 * COIN
    Bitcoin.block_creation_reward(399999).should == 62500 * COIN
    Bitcoin.block_creation_reward(499999).should == 31250 * COIN
    Bitcoin.block_creation_reward(599999).should == 15625 * COIN
    Bitcoin.block_creation_reward(600000).should == 10000 * COIN
    Bitcoin.block_creation_reward(700000).should == 10000 * COIN
  end

  it 'should calculate merkle root from AuxPoW transaction branch' do
    # Taken directly from Dogecoin block #403,931

    # Branch stored as bytes to reflect how data is stored in AuxPow class
    branch = [
      "\xbe\x07\x90\x78\x86\x93\x99\xfa\xcc\xaa\x76\x4c\x10\xe9\xdf\x6e\x99\x81\x70\x17\x59\xad\x18\xe1\x37\x24\xd9\xca\x58\x83\x13\x48",
      "\x5f\x5b\xfb\x2c\x79\x54\x17\x78\x49\x9c\xab\x95\x6a\x10\x38\x87\x14\x7f\x2a\xb5\xd4\xa7\x17\xf3\x2f\x9e\xee\xbd\x29\xe1\xf8\x94",
      "\xd8\xc6\xfe\x42\xca\x25\x07\x61\x59\xcd\x12\x1a\x5e\x20\xc4\x8c\x1b\xc5\x3a\xb9\x07\x30\x08\x3e\x44\xa3\x34\x56\x6e\xa6\xbb\xcb"
    ]
    mrkl_index = 0
    target = "089b911f5e471c0e1800f3384281ebec5b372fbb6f358790a92747ade271ccdf" # Coinbase TX ID
    Bitcoin.mrkl_branch_root(branch.map(&:hth), target, mrkl_index).should == "f29cd14243ed542d9a0b495efcb9feca1b208bb5b717dc5ac04f068d2fef595a"
  end

  it 'should calculate merkle root from AuxPoW branch' do
    # Taken directly from Dogecoin block #403,931

    # Branch stored as bytes to reflect how data is stored in AuxPow class
    aux_branch = [
      "\x47\xa0\x22\x8b\x06\xc9\x36\x8f\x96\xc5\xf0\x4e\xb1\x09\xf8\x2c\xef\x36\xda\xe7\xc1\xbf\x25\x4c\x1a\x3f\x78\x61\x5e\xb0\xbe\x83",
      "\xee\x67\xde\x31\x75\x76\x58\xdd\xd7\x40\x3e\x1a\x35\xd9\xc0\x6a\x5a\x13\xe6\x68\x98\x44\x3b\x45\x8c\xd6\xa7\x1b\x66\x27\x41\x6c",
      "\xab\x9e\xf9\xbd\xa0\x2c\xad\x27\x90\xef\x9b\xb7\xc9\xa0\x7f\xe1\x79\x1a\x9d\x5a\xe0\x43\x09\xc0\xe9\x06\x48\x19\x19\x4c\x28\x31",
      "\xff\x51\x61\x01\x80\xf6\x4d\x33\xa8\xc1\xba\x1d\xd9\xa9\xd0\x40\x48\x88\xc9\x6e\xaf\xd1\x57\x03\x64\x35\x8b\xbe\x99\x8f\x2d\xfe",
      "\x9e\xe4\x18\x36\x7c\x3b\xce\x06\x5e\x7c\x01\x61\x29\x6e\xaa\x0d\x54\x96\xf9\x0f\x8b\x7b\x24\xeb\xf7\x2c\xc4\xba\xa5\x60\x9a\x1f",
      "\x0b\x35\xf3\x73\x10\xe1\xde\x3f\xa4\xe1\x37\x7c\x02\x12\x62\x20\xe1\x64\xfa\x59\xec\xfe\xdc\xf4\x71\x4e\x61\xad\x74\xcc\x4b\x08"
    ]
    aux_mrkl_index = 56
    target = "0c836b86991631d34a8a68054e2f62db919b39d1ee43c27ab3344d6aa82fa609" # Block hash
    Bitcoin.mrkl_branch_root(aux_branch.map(&:hth), target, aux_mrkl_index).should == "ce3040fdb7e37484f6a1ca4f8f5da81e6b7e404ec91102315a233e03a0c39c95" # Merkle root in coinbase script
  end

  it 'parse AuxPoW' do
    Bitcoin::network = :dogecoin

    block_hash = "60323982f9c5ff1b5a954eac9dc1269352835f47c2c5222691d80f0d50dcf053"
    data = fixtures_file("dogecoin-block-#{block_hash}.bin")
    block = P::Block.new(data)
    aux_pow = block.aux_pow
    aux_pow.nil?.should == false
    aux_pow.mrkl_index.should == 0

    parent_block_merkle_root = Bitcoin.mrkl_branch_root(aux_pow.branch.map(&:reverse_hth), aux_pow.tx.hash, aux_pow.mrkl_index)
    parent_block_merkle_root.should == aux_pow.parent_block.mrkl_root.reverse.unpack("H*")[0]

    # Find the merged mining header in the coinbase input script
    merged_mining_header = "\xfa\xbemm"
    script = aux_pow.tx.in[0].script
    header_idx = script.index(merged_mining_header)

    header_idx.should == 4
    
    chain_merkle_root = Bitcoin.mrkl_branch_root(aux_pow.aux_branch.map(&:reverse_hth), block_hash, aux_pow.aux_index)
    
    # Drop everything up to the merged mining data
    script = script.slice(header_idx + merged_mining_header.length, chain_merkle_root.length / 2 + 8)

    tx_root_hash = script.slice(0, chain_merkle_root.length / 2).unpack("H*")[0]
    chain_merkle_root.should == tx_root_hash

    merkle_branch_size = script.slice(chain_merkle_root.length / 2, 4).unpack("V")[0]
    merkle_branch_size.should == (1 << aux_pow.aux_branch.length)

    # Choose a pseudo-random slot in the chain merkle tree
    # but have it be fixed for a size/nonce/chain combination.
    nonce = script.slice(chain_merkle_root.length / 2 + 4, 4).unpack("V")[0]
    rand = nonce
    rand = rand * 1103515245 + 12345
    rand += Bitcoin.network[:auxpow_chain_id]
    rand = rand * 1103515245 + 12345

    aux_pow.aux_index.should == (rand % merkle_branch_size)
  end

end