#!/usr/bin/env python3
import pytest
from helpers.cluster import ClickHouseCluster
import random
import string
import os
import time

cluster = ClickHouseCluster(__file__)
node1 = cluster.add_instance('node1', main_configs=['configs/enable_test_keeper1.xml', 'configs/log_conf.xml'], stay_alive=True)
node2 = cluster.add_instance('node2', main_configs=['configs/enable_test_keeper2.xml', 'configs/log_conf.xml'], stay_alive=True)
node3 = cluster.add_instance('node3', main_configs=['configs/enable_test_keeper3.xml', 'configs/log_conf.xml'], stay_alive=True)

from kazoo.client import KazooClient, KazooState

@pytest.fixture(scope="module")
def started_cluster():
    try:
        cluster.start()

        yield cluster

    finally:
        cluster.shutdown()

def get_fake_zk(nodename, timeout=30.0):
    _fake_zk_instance = KazooClient(hosts=cluster.get_instance_ip(nodename) + ":9181", timeout=timeout)
    def reset_listener(state):
        nonlocal _fake_zk_instance
        print("Fake zk callback called for state", state)
        if state != KazooState.CONNECTED:
            _fake_zk_instance._reset()

    _fake_zk_instance.add_listener(reset_listener)
    _fake_zk_instance.start()
    return _fake_zk_instance

def stop_zk(zk):
    try:
        if zk:
            zk.stop()
            zk.close()
    except:
        pass


def test_recover_from_snapshot(started_cluster):
    try:
        node1_zk = node2_zk = node3_zk = None
        node1_zk = get_fake_zk("node1")
        node2_zk = get_fake_zk("node2")
        node3_zk = get_fake_zk("node3")

        node1_zk.create("/test_snapshot_multinode_recover", "somedata".encode())

        node2_zk.sync("/test_snapshot_multinode_recover")
        node3_zk.sync("/test_snapshot_multinode_recover")

        assert node1_zk.get("/test_snapshot_multinode_recover")[0] == b"somedata"
        assert node2_zk.get("/test_snapshot_multinode_recover")[0] == b"somedata"
        assert node3_zk.get("/test_snapshot_multinode_recover")[0] == b"somedata"

        node3.stop_clickhouse(kill=True)

        # at least we will have 2 snapshots
        for i in range(435):
            node1_zk.create("/test_snapshot_multinode_recover" + str(i), ("somedata" + str(i)).encode())

        for i in range(435):
            if i % 10 == 0:
                node1_zk.delete("/test_snapshot_multinode_recover" + str(i))

    finally:
        for zk in [node1_zk, node2_zk, node3_zk]:
            stop_zk(zk)

    # stale node should recover from leader's snapshot
    # with some sanitizers can start longer than 5 seconds
    node3.start_clickhouse(20)

    try:
        node1_zk = node2_zk = node3_zk = None
        node1_zk = get_fake_zk("node1")
        node2_zk = get_fake_zk("node2")
        node3_zk = get_fake_zk("node3")

        node1_zk.sync("/test_snapshot_multinode_recover")
        node2_zk.sync("/test_snapshot_multinode_recover")
        node3_zk.sync("/test_snapshot_multinode_recover")

        assert node1_zk.get("/test_snapshot_multinode_recover")[0] == b"somedata"
        assert node2_zk.get("/test_snapshot_multinode_recover")[0] == b"somedata"
        assert node3_zk.get("/test_snapshot_multinode_recover")[0] == b"somedata"

        for i in range(435):
            if i % 10 != 0:
                assert node1_zk.get("/test_snapshot_multinode_recover" + str(i))[0] == ("somedata" + str(i)).encode()
                assert node2_zk.get("/test_snapshot_multinode_recover" + str(i))[0] == ("somedata" + str(i)).encode()
                assert node3_zk.get("/test_snapshot_multinode_recover" + str(i))[0] == ("somedata" + str(i)).encode()
            else:
                assert node1_zk.exists("/test_snapshot_multinode_recover" + str(i)) is None
                assert node2_zk.exists("/test_snapshot_multinode_recover" + str(i)) is None
                assert node3_zk.exists("/test_snapshot_multinode_recover" + str(i)) is None
    finally:
        for zk in [node1_zk, node2_zk, node3_zk]:
            stop_zk(zk)