/*
 * Copyright (c) 2019 MariaDB Corporation Ab
 *
 * Use of this software is governed by the Business Source License included
 * in the LICENSE.TXT file and at www.mariadb.com/bsl11.
 *
 * Change Date: 2023-01-01
 *
 * On the date above, in accordance with the Business Source License, use
 * of this software will be governed by version 2 or later of the General
 * Public License.
 */

#include "testconnections.h"
#include <iostream>
#include <maxbase/format.hh>

using std::string;
using std::cout;

int get_master_server_id(TestConnections& test)
{
    MYSQL* conn = test.maxscales->open_rwsplit_connection(0);
    int id = -1;
    char str[1024];

    if (find_field(conn, "SELECT @@server_id, @@last_insert_id;", "@@server_id", str) == 0)
    {
        id = atoi(str);
    }

    mysql_close(conn);
    return id;
}

int main(int argc, char** argv)
{
    Mariadb_nodes::require_gtid(true);
    TestConnections::skip_maxscale_start(true);

    TestConnections test(argc, argv);

    if (test.repl->N < 4)
    {
        test.expect(false, "This test requires at least 4 backends.");
        return test.global_result;
    }

    test.repl->connect();
    auto server_ids = test.repl->get_all_server_ids();

    // Stop the master and the last slave, then start MaxScale.
    int master_ind = 0;
    int last_slave_ind = 3;

    string master_name = mxb::string_printf("server%i", master_ind + 1);
    string slave_name = mxb::string_printf("server%i", last_slave_ind + 1);

    test.tprintf("Stopping %s and %s.", master_name.c_str(), slave_name.c_str());
    test.repl->stop_node(master_ind);
    test.repl->stop_node(last_slave_ind);

    test.tprintf("Starting MaxScale");
    test.start_maxscale(0);

    sleep(3);
    test.maxscales->wait_for_monitor(3);

    test.log_includes(0, "Performing automatic failover");
    int new_master_id = get_master_server_id(test);
    int expected_id1 = server_ids[1];
    int expected_id2 = server_ids[2];
    test.expect(new_master_id == expected_id1 || new_master_id == expected_id2,
                "Unexpected master server id. Got %i when %i or %i was expected.",
                new_master_id, expected_id1, expected_id2);

    if (test.ok())
    {
        // Restart server4, check that it rejoins.
        test.repl->start_node(last_slave_ind, (char*)"");
        test.maxscales->wait_for_monitor(2);

        auto states = test.maxscales->get_server_status(slave_name.c_str());
        test.expect(states.count("Slave") == 1, "%s is not replicating as it should.", slave_name.c_str());
    }

    if (test.ok())
    {
        // Finally, bring back old master and swap to it.
        test.repl->start_node(master_ind, (char*)"");
        test.maxscales->wait_for_monitor(2);

        test.tprintf("Switching back old master %s.", master_name.c_str());
        string switchover = "call command mariadbmon switchover MariaDB-Monitor " + master_name;
        test.maxscales->execute_maxadmin_command(0, switchover.c_str());
        test.maxscales->wait_for_monitor(2);
        new_master_id = get_master_server_id(test);
        test.expect(new_master_id == server_ids[master_ind], "Switchover to original master failed.");
    }
    return test.global_result;
}