#!/usr/bin/env python3
# Copyright (c) 2014-2021 The Bitcoin Core developers
# Distributed under the MIT software license, see the accompanying
# file COPYING or http://www.opensource.org/licenses/mit-license.php.
"""Test mining RPCs

- getmininginfo
- getblocktemplate proposal mode
- submitblock"""

import copy

from test_framework.blocktools import (
    create_coinbase,
    get_witness_script,
    NORMAL_GBT_REQUEST_PARAMS,
    TIME_GENESIS_BLOCK,
)
from test_framework.messages import (
    CBlock,
    CBlockHeader,
    BLOCK_HEADER_SIZE,
    ser_uint256,
)
from test_framework.p2p import P2PDataStore
from test_framework.test_framework import BitcoinTestFramework
from test_framework.util import (
    assert_equal,
    assert_raises_rpc_error,
)
from test_framework.wallet import MiniWallet


VERSIONBITS_TOP_BITS = 0x20000000
VERSIONBITS_DEPLOYMENT_TESTDUMMY_BIT = 28


def assert_template(node, block, expect, rehash=True):
    if rehash:
        block.hashMerkleRoot = block.calc_merkle_root()
    rsp = node.getblocktemplate(template_request={
        'data': block.serialize().hex(),
        'mode': 'proposal',
        'rules': ['segwit'],
    })
    assert_equal(rsp, expect)


class MiningTest(BitcoinTestFramework):
    def set_test_params(self):
        self.num_nodes = 2
        self.setup_clean_chain = True
        self.supports_cli = False

    def mine_chain(self):
        self.log.info('Create some old blocks')
        for t in range(TIME_GENESIS_BLOCK, TIME_GENESIS_BLOCK + 200 * 600, 600):
            self.nodes[0].setmocktime(t)
            self.generate(self.wallet, 1, sync_fun=self.no_op)
        mining_info = self.nodes[0].getmininginfo()
        assert_equal(mining_info['blocks'], 200)
        assert_equal(mining_info['currentblocktx'], 0)
        assert_equal(mining_info['currentblockweight'], 4300)

        self.log.info('test blockversion')
        self.restart_node(0, extra_args=[f'-mocktime={t}', '-blockversion=1337'])
        self.connect_nodes(0, 1)
        assert_equal(1337, self.nodes[0].getblocktemplate(NORMAL_GBT_REQUEST_PARAMS)['version'])
        self.restart_node(0, extra_args=[f'-mocktime={t}'])
        self.connect_nodes(0, 1)
        assert_equal(VERSIONBITS_TOP_BITS + (1 << VERSIONBITS_DEPLOYMENT_TESTDUMMY_BIT), self.nodes[0].getblocktemplate(NORMAL_GBT_REQUEST_PARAMS)['version'])
        self.restart_node(0)
        self.connect_nodes(0, 1)

    def run_test(self):
        node = self.nodes[0]
        self.wallet = MiniWallet(node)
        self.mine_chain()

        def assert_submitblock(block, result_str_1, result_str_2=None):
            block.solve()
            result_str_2 = result_str_2 or 'duplicate-invalid'
            assert_equal(result_str_1, node.submitblock(hexdata=block.serialize().hex()))
            assert_equal(result_str_2, node.submitblock(hexdata=block.serialize().hex()))

        self.log.info('getmininginfo')
        mining_info = node.getmininginfo()
        assert_equal(mining_info['blocks'], 200)
        assert_equal(mining_info['chain'], self.chain)
        assert 'currentblocktx' not in mining_info
        assert 'currentblockweight' not in mining_info
        assert_equal(mining_info['pooledtx'], 0)

        self.log.info("getblocktemplate: Test default witness commitment")
        txid = int(self.wallet.send_self_transfer(from_node=node)['wtxid'], 16)
        tmpl = node.getblocktemplate(NORMAL_GBT_REQUEST_PARAMS)

        # Check that default_witness_commitment is present.
        assert 'default_witness_commitment' in tmpl
        # witness_commitment = tmpl['default_witness_commitment']

        # Check that default_witness_commitment is correct.
        witness_root = CBlock.get_merkle_root([ser_uint256(0),
                                               ser_uint256(txid)])
        script = get_witness_script(witness_root, 0)
        assert_equal(script.hex(), "6a24aa21a9ed3160175963f85aa4d48b96b0b1c16eb02693d2ee908f73391e78a73747722e72") # ELEMENTS: use `script` to placate linter

        # ELEMENTS: The following assertion fails because
        # (1) Elements appears to use a different merkle tree computation than Bitcoin here
        #     (ComputeFastMerkleRoot vs ComputeMerkleRoot)
        # (2) Elements does some slightly different thing than Bitcoin with what goes into the merkle tree
        #     (see the "ELEMENTS:" comment in validation.cpp:3399.)
        # assert_equal(witness_commitment, script.hex())

        # Mine a block to leave initial block download and clear the mempool
        self.generatetoaddress(node, 1, node.get_deterministic_priv_key().address)
        tmpl = node.getblocktemplate(NORMAL_GBT_REQUEST_PARAMS)
        self.log.info("getblocktemplate: Test capability advertised")
        assert 'proposal' in tmpl['capabilities']
        assert 'coinbasetxn' not in tmpl

        next_height = int(tmpl["height"])
        coinbase_tx = create_coinbase(height=next_height)
        # sequence numbers must not be max for nLockTime to have effect
        coinbase_tx.vin[0].nSequence = 2**32 - 2
        coinbase_tx.rehash()

        block = CBlock()
        block.nVersion = tmpl["version"]
        block.hashPrevBlock = int(tmpl["previousblockhash"], 16)
        block.nTime = tmpl["curtime"]
        block.block_height = node.getblockcount()+1
        block.nBits = 0
        block.nNonce = 0
        block.vtx = [coinbase_tx]

        self.log.info("getblocktemplate: segwit rule must be set")
        assert_raises_rpc_error(-8, "getblocktemplate must be called with the segwit rule set", node.getblocktemplate)

        self.log.info("getblocktemplate: Test valid block")
        assert_template(node, block, None)

        self.log.info("submitblock: Test block decode failure")
        assert_raises_rpc_error(-22, "Block decode failed", node.submitblock, block.serialize()[:-15].hex())

        self.log.info("getblocktemplate: Test bad input hash for coinbase transaction")
        bad_block = copy.deepcopy(block)
        bad_block.vtx[0].vin[0].prevout.hash += 1
        bad_block.vtx[0].rehash()
        assert_template(node, bad_block, 'bad-cb-missing')

        self.log.info("submitblock: Test invalid coinbase transaction")
        assert_raises_rpc_error(-22, "Block does not start with a coinbase", node.submitblock, bad_block.serialize().hex())

        self.log.info("getblocktemplate: Test truncated final transaction")
        assert_raises_rpc_error(-22, "Block decode failed", node.getblocktemplate, {
            'data': block.serialize()[:-1].hex(),
            'mode': 'proposal',
            'rules': ['segwit'],
        })

        self.log.info("getblocktemplate: Test duplicate transaction")
        bad_block = copy.deepcopy(block)
        bad_block.vtx.append(bad_block.vtx[0])
        assert_template(node, bad_block, 'bad-txns-duplicate')
        assert_submitblock(bad_block, 'bad-txns-duplicate', 'bad-txns-duplicate')

        self.log.info("getblocktemplate: Test invalid transaction")
        bad_block = copy.deepcopy(block)
        bad_tx = copy.deepcopy(bad_block.vtx[0])
        bad_tx.vin[0].prevout.hash = 255
        bad_tx.rehash()
        bad_block.vtx.append(bad_tx)
        assert_template(node, bad_block, 'bad-txns-inputs-missingorspent')
        assert_submitblock(bad_block, 'bad-txns-inputs-missingorspent')

        self.log.info("getblocktemplate: Test nonfinal transaction")
        bad_block = copy.deepcopy(block)
        bad_block.vtx[0].nLockTime = 2**32 - 1
        bad_block.vtx[0].rehash()
        assert_template(node, bad_block, 'bad-txns-nonfinal')
        assert_submitblock(bad_block, 'bad-txns-nonfinal')

        self.log.info("getblocktemplate: Test bad tx count")
        # The tx count is immediately after the block header
        TX_COUNT_OFFSET = len(super(CBlock, block).serialize())
        bad_block_sn = bytearray(block.serialize())
        assert_equal(bad_block_sn[BLOCK_HEADER_SIZE], 1)
        bad_block_sn[BLOCK_HEADER_SIZE] += 1
        assert_raises_rpc_error(-22, "Block decode failed", node.getblocktemplate, {
            'data': bad_block_sn.hex(),
            'mode': 'proposal',
            'rules': ['segwit'],
        })

        # No PoW test
#        self.log.info("getblocktemplate: Test bad bits")
#        bad_block = copy.deepcopy(block)
#        bad_block.nBits = 469762303  # impossible in the real world
#        assert_template(node, bad_block, 'bad-diffbits')

        self.log.info("getblocktemplate: Test bad merkle root")
        bad_block = copy.deepcopy(block)
        bad_block.hashMerkleRoot += 1
        assert_template(node, bad_block, 'bad-txnmrklroot', False)
        assert_submitblock(bad_block, 'bad-txnmrklroot', 'bad-txnmrklroot')

        self.log.info("getblocktemplate: Test bad timestamps")
        bad_block = copy.deepcopy(block)
        bad_block.nTime = 2**31 - 1
        assert_template(node, bad_block, 'time-too-new')
        assert_submitblock(bad_block, 'time-too-new', 'time-too-new')
        bad_block.nTime = 0
        assert_template(node, bad_block, 'time-too-old')
        assert_submitblock(bad_block, 'time-too-old', 'time-too-old')

        self.log.info("getblocktemplate: Test not best block")
        bad_block = copy.deepcopy(block)
        bad_block.hashPrevBlock = 123
        assert_template(node, bad_block, 'inconclusive-not-best-prevblk')
        assert_submitblock(bad_block, 'prev-blk-not-found', 'prev-blk-not-found')

        self.log.info('submitheader tests')
        assert_raises_rpc_error(-22, 'Block header decode failed', lambda: node.submitheader(hexdata='xx' * TX_COUNT_OFFSET))
        assert_raises_rpc_error(-22, 'Block header decode failed', lambda: node.submitheader(hexdata='ff' * (TX_COUNT_OFFSET-2)))
        assert_raises_rpc_error(-25, 'Must submit previous header', lambda: node.submitheader(hexdata=super(CBlock, bad_block).serialize().hex()))

        block.nTime += 1
        block.solve()

        def chain_tip(b_hash, *, status='headers-only', branchlen=1):
            return {'hash': b_hash, 'height': 202, 'branchlen': branchlen, 'status': status}

        assert chain_tip(block.hash) not in node.getchaintips()
        node.submitheader(hexdata=block.serialize().hex())
        assert chain_tip(block.hash) in node.getchaintips()
        node.submitheader(hexdata=CBlockHeader(block).serialize().hex())  # Noop
        assert chain_tip(block.hash) in node.getchaintips()

        bad_block_root = copy.deepcopy(block)
        bad_block_root.hashMerkleRoot += 2
        bad_block_root.solve()
        assert chain_tip(bad_block_root.hash) not in node.getchaintips()
        node.submitheader(hexdata=CBlockHeader(bad_block_root).serialize().hex())
        assert chain_tip(bad_block_root.hash) in node.getchaintips()
        # Should still reject invalid blocks, even if we have the header:
        assert_equal(node.submitblock(hexdata=bad_block_root.serialize().hex()), 'bad-txnmrklroot')
        assert_equal(node.submitblock(hexdata=bad_block_root.serialize().hex()), 'bad-txnmrklroot')
        assert chain_tip(bad_block_root.hash) in node.getchaintips()
        # We know the header for this invalid block, so should just return early without error:
        node.submitheader(hexdata=CBlockHeader(bad_block_root).serialize().hex())
        assert chain_tip(bad_block_root.hash) in node.getchaintips()

        bad_block_lock = copy.deepcopy(block)
        bad_block_lock.vtx[0].nLockTime = 2**32 - 1
        bad_block_lock.vtx[0].rehash()
        bad_block_lock.hashMerkleRoot = bad_block_lock.calc_merkle_root()
        bad_block_lock.solve()
        assert_equal(node.submitblock(hexdata=bad_block_lock.serialize().hex()), 'bad-txns-nonfinal')
        assert_equal(node.submitblock(hexdata=bad_block_lock.serialize().hex()), 'duplicate-invalid')
        # Build a "good" block on top of the submitted bad block
        bad_block2 = copy.deepcopy(block)
        bad_block2.hashPrevBlock = bad_block_lock.sha256
        bad_block2.solve()
        assert_raises_rpc_error(-25, 'bad-prevblk', lambda: node.submitheader(hexdata=CBlockHeader(bad_block2).serialize().hex()))

        # Should reject invalid header right away
        bad_block_time = copy.deepcopy(block)
        bad_block_time.nTime = 1
        bad_block_time.solve()
        assert_raises_rpc_error(-25, 'time-too-old', lambda: node.submitheader(hexdata=CBlockHeader(bad_block_time).serialize().hex()))

        # Should ask for the block from a p2p node, if they announce the header as well:
        peer = node.add_p2p_connection(P2PDataStore())
        peer.wait_for_getheaders(timeout=5)  # Drop the first getheaders
        peer.send_blocks_and_test(blocks=[block], node=node)
        # Must be active now:
        assert chain_tip(block.hash, status='active', branchlen=0) in node.getchaintips()

        # Building a few blocks should give the same results
        self.generatetoaddress(node, 10, node.get_deterministic_priv_key().address)
        assert_raises_rpc_error(-25, 'time-too-old', lambda: node.submitheader(hexdata=CBlockHeader(bad_block_time).serialize().hex()))
        assert_raises_rpc_error(-25, 'bad-prevblk', lambda: node.submitheader(hexdata=CBlockHeader(bad_block2).serialize().hex()))
        node.submitheader(hexdata=CBlockHeader(block).serialize().hex())
        node.submitheader(hexdata=CBlockHeader(bad_block_root).serialize().hex())
        assert_equal(node.submitblock(hexdata=block.serialize().hex()), 'duplicate')  # valid


if __name__ == '__main__':
    MiningTest().main()
