#!/usr/bin/env python3
# Copyright (c) 2014-2020 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 the invalidateblock RPC."""

from test_framework.test_framework import BitcoinTestFramework
from test_framework.address import ADDRESS_BCRT1_UNSPENDABLE_DESCRIPTOR
from test_framework.util import (
    assert_equal,
    assert_raises_rpc_error,
)


class InvalidateTest(BitcoinTestFramework):
    def set_test_params(self):
        self.setup_clean_chain = True
        self.num_nodes = 3

    def setup_network(self):
        self.setup_nodes()

    def run_test(self):
        self.log.info("Make sure we repopulate setBlockIndexCandidates after InvalidateBlock:")
        self.log.info("Mine 4 blocks on Node 0")
        self.generate(self.nodes[0], 4, sync_fun=self.no_op)
        assert_equal(self.nodes[0].getblockcount(), 4)
        besthash_n0 = self.nodes[0].getbestblockhash()

        self.log.info("Mine competing 6 blocks on Node 1")
        self.generate(self.nodes[1], 6, sync_fun=self.no_op)
        assert_equal(self.nodes[1].getblockcount(), 6)

        self.log.info("Connect nodes to force a reorg")
        self.connect_nodes(0, 1)
        self.sync_blocks(self.nodes[0:2])
        assert_equal(self.nodes[0].getblockcount(), 6)
        badhash = self.nodes[1].getblockhash(2)

        self.log.info("Invalidate block 2 on node 0 and verify we reorg to node 0's original chain")
        self.nodes[0].invalidateblock(badhash)
        assert_equal(self.nodes[0].getblockcount(), 4)
        assert_equal(self.nodes[0].getbestblockhash(), besthash_n0)

        self.log.info("Make sure we won't reorg to a lower work chain:")
        self.connect_nodes( 1, 2)
        self.log.info("Sync node 2 to node 1 so both have 6 blocks")
        self.sync_blocks(self.nodes[1:3])
        assert_equal(self.nodes[2].getblockcount(), 6)
        self.log.info("Invalidate block 5 on node 1 so its tip is now at 4")
        self.nodes[1].invalidateblock(self.nodes[1].getblockhash(5))
        assert_equal(self.nodes[1].getblockcount(), 4)
        self.log.info("Invalidate block 3 on node 2, so its tip is now 2")
        self.nodes[2].invalidateblock(self.nodes[2].getblockhash(3))
        assert_equal(self.nodes[2].getblockcount(), 2)
        self.log.info("..and then mine a block")
        self.generate(self.nodes[2], 1, sync_fun=self.no_op)
        self.log.info("Verify all nodes are at the right height")
        self.wait_until(lambda: self.nodes[2].getblockcount() == 3, timeout=5)
        self.wait_until(lambda: self.nodes[0].getblockcount() == 4, timeout=5)
        self.wait_until(lambda: self.nodes[1].getblockcount() == 4, timeout=5)

        self.log.info("Make sure ResetBlockFailureFlags does the job correctly")
        self.restart_node(0, extra_args=["-checkblocks=5"])
        self.restart_node(1, extra_args=["-checkblocks=5"])
        self.connect_nodes(0, 1)
        self.generate(self.nodes[0], 10, sync_fun=lambda: self.sync_blocks(self.nodes[0:2]))
        newheight = self.nodes[0].getblockcount()
        for j in range(2):
            self.restart_node(0, extra_args=["-checkblocks=5"])
            tip = self.generate(self.nodes[0], 10, sync_fun=self.no_op)[-1]
            self.generate(self.nodes[1], 9, sync_fun=self.no_op)
            self.connect_nodes(0, 1)
            self.sync_blocks(self.nodes[0:2])
            assert_equal(self.nodes[0].getblockcount(), newheight + 10 * (j + 1))
            assert_equal(self.nodes[1].getblockcount(), newheight + 10 * (j + 1))
            assert_equal(self.nodes[1].getbestblockhash(), tip)

        tip = self.nodes[1].getbestblockhash()
        self.nodes[1].invalidateblock(self.nodes[1].getblockhash(newheight + 1))
        self.nodes[1].invalidateblock(self.nodes[1].getblockhash(newheight + 1))

        assert_equal(self.nodes[1].getblockcount(), newheight)
        self.restart_node(1, extra_args=["-checkblocks=5"])
        self.wait_until(lambda: self.nodes[1].getblockcount() == newheight + 20)
        assert_equal(tip, self.nodes[1].getbestblockhash())

        self.log.info("Verify that we reconsider all ancestors as well")
        blocks = self.generatetodescriptor(self.nodes[1], 10, ADDRESS_BCRT1_UNSPENDABLE_DESCRIPTOR, sync_fun=self.no_op)
        assert_equal(self.nodes[1].getbestblockhash(), blocks[-1])
        # Invalidate the two blocks at the tip
        self.nodes[1].invalidateblock(blocks[-1])
        self.nodes[1].invalidateblock(blocks[-2])
        assert_equal(self.nodes[1].getbestblockhash(), blocks[-3])
        # Reconsider only the previous tip
        self.nodes[1].reconsiderblock(blocks[-1])
        # Should be back at the tip by now
        assert_equal(self.nodes[1].getbestblockhash(), blocks[-1])

        self.log.info("Verify that we reconsider all descendants")
        blocks = self.generatetodescriptor(self.nodes[1], 10, ADDRESS_BCRT1_UNSPENDABLE_DESCRIPTOR, sync_fun=self.no_op)
        assert_equal(self.nodes[1].getbestblockhash(), blocks[-1])
        # Invalidate the two blocks at the tip
        self.nodes[1].invalidateblock(blocks[-2])
        self.nodes[1].invalidateblock(blocks[-4])
        assert_equal(self.nodes[1].getbestblockhash(), blocks[-5])
        # Reconsider only the previous tip
        self.nodes[1].reconsiderblock(blocks[-4])
        # Should be back at the tip by now
        assert_equal(self.nodes[1].getbestblockhash(), blocks[-1])

        self.log.info("Verify that invalidating an unknown block throws an error")
        assert_raises_rpc_error(-5, "Block not found", self.nodes[1].invalidateblock, "00" * 32)
        assert_equal(self.nodes[1].getbestblockhash(), blocks[-1])


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