/*
	Copyright (c)  2013, 2014 IOnU Security Inc. All rights reserved. Copyright (c) 2015, 2016 Sequence Logic, Inc.
	Created August 2013 by Kendrick Webster

	K2Daemon/MongoDB.h - MongoDB database interface common functions
*/
#pragma once

#include "global.h"
#include <mongoc.h>
#include <stdint.h>
#include <string>
#include <list>

/*
   The Mongo database connection is shared (global) for this application.
   Modules that operate on specific databases and collections use this one
   global shared connection.

   This namespace also has common/shared utility functions.
*/
namespace MongoDB
{
    constexpr const char*   DEFAULT_HOST = "127.0.0.1";
    constexpr uint16_t      DEFAULT_PORT = 27017;

    // Call Connect or ConnectReplica before using any other MongoDB functions

	// Connect to a single MongoDB server
	success_t Connect(const char* host = DEFAULT_HOST, int port = DEFAULT_PORT);

    // Connect to a MongoDB replica set
    //success_t ConnectReplica(const std::string& replica_set_name, const host_list_t& hosts);
    success_t ConnectReplica(const std::string& replica_set_name, const std::string& hosts);

	// Disconnect from MongoDB server or replica set
	void Disconnect(void);

    // Reconnect, this needs to be done if connection errors occur, see
    // http://api.mongodb.org/c/current/connections.html
    // http://devhost.ionu.int:8080/jira/browse/IONU-1163
    // Note that this may fail when the primary of a replica set is lost and Mongo hasn't yet
    // elected a new primary.  If it does fail, calling other mongo API functions can lock up
    // the thread (as of ver 0.8.1 of the Mongo C driver).
    success_t Reconnect(void);

	// Returns connection datastruct, NULL if not connected (or if MongoDB is temporarilly down)
	mongoc_client_t* GetConnection(void);

    // Returns true if MongoDB is temporarilly down (i.e. when the primary of a replica set is
    // lost and Mongo hasn't yet elected a new primary)
    bool IsTemporaryOutage(void);

	// returns human-readable text (suitable for logging) for a MongoDB error code
	const char* ErrorString(mongoc_error_code_t e);

    // Call periodically to do background tasks (i.e. reconnect to MongoDB after a transient connection issue causes a disconnect)
    void Timer(void);
}