#pragma once
/*
 * Copyright (c) 2016 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: 2022-01-01
 *
 * 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.
 */

/**
 * @file housekeeper.h A mechanism to have task run periodically
 */

#include <maxscale/cdefs.h>
#include <maxscale/dcb.h>

MXS_BEGIN_DECLS

/**
 * The task callback function
 *
 * The parameter is the user data given to the `hktask_add` function.
 *
 * If the function returns true, the same task is added back to the queue and
 * executed again at a later point in time. If the function returns false,
 * the task is removed.
 */
typedef bool (*TASKFN)(void *data);

/**
 * Initialises the housekeeper mechanism.
 *
 * A call to any of the other housekeeper functions can be made only if
 * this function returns successfully. This function must be called after all
 * module level initialization is done but before any monitors or services are
 * started.
 *
 * @return True if the housekeeper mechanism was initialized, false otherwise.
 */
bool hkinit();

/**
 * Start the housekeeper thread
 *
 * @return True if the housekeeper mechanism was started
 */
bool hkstart();

/**
 * Waits for the housekeeper thread to finish.
 */
void hkfinish();

/**
 * @brief Add a new task
 *
 * The task will be first run @c frequency seconds after this call is
 * made and will the be executed repeatedly every frequency seconds
 * until the task is removed.
 *
 * Task names must be unique.
 *
 * @param name      Task name
 * @param task      Function to execute
 * @param data      Data passed to function as the parameter
 * @param frequency Frequency of execution
 */
void hktask_add(const char *name, TASKFN func, void *data, int frequency);

/**
 * @brief Remove all tasks with this name
 *
 * @param name Task name
 */
void hktask_remove(const char *name);

/**
 * @brief Show the tasks that are scheduled for the house keeper
 *
 * @param pDcb The DCB to send to output
 */
void hkshow_tasks(DCB *pdcb);

/**
 * @brief Show tasks as JSON resource
 *
 * @param host Hostname of this server
 *
 * @return Collection of JSON formatted task resources
 */
json_t* hk_tasks_json(const char* host);

MXS_END_DECLS