/** @file
 * @brief The abstract service class. This class represents all services.
 *
 *
 *
 * @copyright Intra2net AG
 * @license GPLv2
*/

#include "service.hpp"
#include <boost/foreach.hpp>

using namespace std;

/// Number of update errors until a service will be blocked
const int MaxErrorCount = 3;
/// Number of seconds a service will be blocked if MaxErrorCount is reached
const int ErrorBlockServiceSeconds = 15 * 60;

/**
 * Default Constructor
 */
Service::Service()
    : Login("NOT SERIALIZED")
    , Password("NOT SERIALIZED")
    , ActualIP("0.0.0.0")
    , ActualIPIsBurnt(false)
    , Activated(false)
    , UpdateInterval(15)
    , MaxUpdatesWithinInterval(3)
    , MaxEqualUpdatesInSuccession(2)
    , DNSCacheTTL(0)
    , ErrorCount(0)
    , ErrorServiceBlockedUntil(0)
    , Log(new Logger())
{
}


/**
 * Default Destructor needed for deserialization.
 */
Service::~Service()
{
}


/**
 * Setter for member Protocol.
 * @param _protocol Value to set Protocol to.
 */
void Service::set_protocol(const string& _protocol)
{
    Protocol = _protocol;
}


/**
 * Getter for memeber Protocol.
 * @return Value of member Protocol.
 */
string Service::get_protocol() const
{
    return Protocol;
}


/**
 * Setter for member Hostname.
 * @param _hostname Value to set Hostname to.
 */
void Service::set_hostname(const string& _hostname)
{
    Hostname = _hostname;
}


/**
 * Getter for member Hostname.
 * @return Value of member Hostname.
 */
string Service::get_hostname() const
{
    return Hostname;
}


/**
 * Setter for member Login.
 * @param _login Value to set Login to.
 */
void Service::set_login(const string& _login)
{
    Login = _login;
}


/**
 * Getter for member Login.
 * @return Value of member Login.
 */
string Service::get_login() const
{
    return Login;
}


/**
 * Setter for member Password.
 * @param _password Value to set Password to.
 */
void Service::set_password(const string& _password)
{
    Password = _password;
}


/**
 * Getter for member Password.
 * @return Value of member Password.
 */
string Service::get_password() const
{
    return Password;
}



void Service::set_logger(const Logger::Ptr& _log)
{
    Log = _log;
}


/**
 * Getter for member Log.
 * @return Shared pointer to Logger object.
 */
Logger::Ptr Service::get_logger() const
{
    return Log;
}


/**
 * Setter for member LastUpdates.
 * @param _last_updates Value to set LastUpdates to.
 */
void Service::set_last_updates(std::map<time_t,std::string> _last_updates)
{
    std::map<time_t,std::string> temp = _last_updates;
    LastUpdates.swap(temp);
}


/**
 * Getter for member LastUpdates.
 * @return Value of member LastUpdates.
 */
const std::map<time_t,std::string> Service::get_last_updates() const
{
    return LastUpdates;
}


/**
 * Setter for member ActualIP.
 * @param _actual_ip Value to set ActualIP to.
 */
void Service::set_actual_ip(const std::string& _actual_ip)
{
    ActualIP = _actual_ip;
}


/**
 * Getter for member ActualIP.
 * @return Value of member ActualIP.
 */
std::string Service::get_actual_ip() const
{
    return ActualIP;
}


/**
 * Overloading of comparison operator.
 * @param other Reference to other Service object.
 * @return True if they equal, false if not.
 */
bool Service::operator== (const Service& other) const
{
    if ( ( this->Protocol == other.Protocol ) && ( this->Hostname == other.Hostname ) )
        return true;
    return false;
}


/**
 * Overloading of disparate operator.
 * @param other Reference to other Service object.
 * @return True if they differ, false if they are equal.
 */
bool Service::operator!= (const Service& other) const
{
    return !(*this == other);
}


/**
 * Checks if update will exceed max update interval or if the IP address is burnt.
 * @param current_time Current time.
 * @param changed_to_online True if we just changed to online, false if we were already online
 * @param ip_host The new ip to set for the hostname.
 * @return True if update is allowed, false if update would exceed max update interval.
 */
bool Service::update_allowed(const time_t current_time, bool changed_to_online, const std::string& ip_host)
{
    Log->print_last_updates(ip_host,current_time,UpdateInterval,MaxUpdatesWithinInterval,MaxEqualUpdatesInSuccession,LastUpdates,get_service_name());

    // Check for update interval overstepping.
    int i = 0;
    for ( std::map<time_t,std::string>::reverse_iterator r_iter = LastUpdates.rbegin(); (r_iter != LastUpdates.rend()) && ( i < MaxUpdatesWithinInterval ); r_iter++)
    {
        if ( (i == (MaxUpdatesWithinInterval-1)) && ( (r_iter->first + ((time_t)UpdateInterval*60)) >= current_time ) )
        {
            Log->print_update_not_allowed(changed_to_online,current_time,r_iter->first,MaxUpdatesWithinInterval,get_service_name());
            return false;
        }
        i++;
    }

    if (ActualIPIsBurnt)
    {
        // Changed IP address removes the "burnt state"
        if (ip_host != ActualIP)
            ActualIPIsBurnt = false;
        else
        {
            // IP is burnt and didn't change -> Update not allowed
            return false;
        }
    }

    // Check for burnt IP.
    // Only check for burnt IP address if there are at least max_equal_updates_in_succession entries in the last_updates map.
    if ( (MaxEqualUpdatesInSuccession != 0) && ((int)LastUpdates.size() >= MaxEqualUpdatesInSuccession) )
    {
        bool ip_burnt = true;
        i = 0;
        // Reverse iterate "last_updates" list so the latest update
        // will be the first entry (map key is the unix timestamp)
        for ( std::map<time_t,std::string>::reverse_iterator r_iter = LastUpdates.rbegin();
            ( r_iter != LastUpdates.rend() ) && ( i < MaxEqualUpdatesInSuccession ); r_iter++ )
        {
            if ( ip_host != r_iter->second )
            {
                ip_burnt = false;
                break;
            }
            i++;
        }

        if ( ip_burnt )
        {
            // IP Address is burnt. Too many updates in succession with the same IP. Log once.
            Log->print_ip_burnt(ip_host,get_service_name());
            ActualIPIsBurnt = true;
            return false;
        }
    }

    return true;
}


/**
 * Service update method, common to each service.
 * @param ip The new ip to set for the hostname.
 * @param current_time Current time
 * @param changed_to_online True if we just changed to online, false if we were already online
 */
void Service::update(const string& ip, const time_t current_time, bool changed_to_online)
{
    const std::string service_name = get_service_name();

    // Check if service is blocked for a short period of time (because of update errors)
    if (ErrorServiceBlockedUntil && current_time < ErrorServiceBlockedUntil)
    {
        Log->print_update_service_is_blocked(service_name, ErrorServiceBlockedUntil - current_time);
        return;
    }

    // test if update is permitted by UpdateInterval Status
    if ( update_allowed(current_time, changed_to_online, ip) )
    {
        Log->print_update_service(service_name);

        UpdateErrorCode update_res = perform_update(ip);

        // If update result is other than Generic or NotAuth, we assume that the hostname is activated.
        if ( (update_res != GenericError) && (update_res != NotAuth) )
            set_activated();

        if (update_res == UpdateOk)
        {
            // if update was successful, we need to set the Lastupdated and ActualIP base member.
            set_last_update(current_time,ip);
            ActualIP = ip;
            Log->print_update_service_successful(service_name,ip);

            ErrorCount = 0;
            ErrorServiceBlockedUntil = 0;
        }
        else
        {
            if (update_res == NoChange || update_res == Blocked)
            {
                // Log update for burnt IP logic and update "ActualIP" of this service
                set_last_update(current_time,ip);
                ActualIP = ip;
            }

            // problem while trying to update service
            Log->print_update_service_failure(service_name);

            ++ErrorCount;
            if (ErrorCount >= MaxErrorCount)
            {
                Log->print_block_service(service_name, ErrorBlockServiceSeconds);

                ErrorServiceBlockedUntil = time(NULL) + ErrorBlockServiceSeconds;
                ErrorCount = 0;
            }
        }
    }
}


/**
* Sets the given time into the LastUpdates member and deletes expired entries.
* @param _timeout Value to set into LastUpdates.
*/
void Service::set_last_update(const time_t current_time, const string& ip)
{
    // Insert value into the list.
    LastUpdates.insert(make_pair(current_time,ip));

    // Get the maximum of MaxUpdatesWithinInterval and MaxEqualUpdatesInSuccession
    int maximum = max(MaxUpdatesWithinInterval,MaxEqualUpdatesInSuccession);

    // Check for expired entries:

    // MaxUpdatesWithinInterval given in service config, then use this to check for expired entries.
    if ( maximum > 0 )
    {
        // Delete the oldest entry if there are more than max(MaxUpdatesWithinInterval,MaxEqualUpdatesInSuccession)+1 entries in the list.
        if ( LastUpdates.size() > (size_t)(maximum+1) )
            LastUpdates.erase(LastUpdates.begin());
        return;
    }
    // UpdateInterval given in service config, then use this to check for expired entries.
    else if ( UpdateInterval > 0 )
    {
        // Delete the oldest entry if it's older than current_time - UpdateInterval(minutes) + 1.
        if ( (current_time - ((time_t)UpdateInterval*60) + 1) > LastUpdates.begin()->first )
            LastUpdates.erase(LastUpdates.begin());
        return;
    }
    // Neither MaxUpdatesWithinInterval nor UpdateInterval are given, so keep fix number of 10 entries.
    else
    {
        if ( LastUpdates.size() > 10 )
            LastUpdates.erase(LastUpdates.begin());
        return;
    }
}


/**
 * Getter the last updated time.
 * @return Value of the last update as time_t.
 */
time_t Service::get_last_update_time( )
{
    time_t last_update = 0;
    if ( !LastUpdates.empty() )
    {
        std::map<time_t,std::string>::reverse_iterator r_iter = LastUpdates.rbegin();
        if ( r_iter != LastUpdates.rend() )
            last_update = r_iter->first;
    }
    return last_update;
}


/**
 * Setter for member Timeout.
 * @param _timeout Value to set Timeout to.
 */
void Service::set_update_interval(const int _update_interval)
{
    UpdateInterval = _update_interval;
}


/**
 * Getter for member Timeout.
 * @return Value of Timeout.
 */
int Service::get_update_interval() const
{
    return UpdateInterval;
}


/**
 * Setter for member Max_updates_per_timeout.
 * @param  _max_updates_per_timeout Value to set Max_updates_per_timeout to.
 */
void Service::set_max_updates_within_interval(const int _max_updates_within_interval)
{
    MaxUpdatesWithinInterval = _max_updates_within_interval;
}


/**
 * Getter for member Max_updates_per_timeout.
 * @return Value of Max_updates_per_timeout.
 */
int Service::get_max_updates_within_interval() const
{
    return MaxUpdatesWithinInterval;
}


/**
 * Setter for member MaxEqualUpdatesInSuccession.
 * @param  _max_equal_updates_in_succession Value to set MaxEqualUpdatesInSuccession to.
 */
void Service::set_max_equal_updates_in_succession(const int _max_equal_updates_in_succession)
{
    MaxEqualUpdatesInSuccession = _max_equal_updates_in_succession;
}


/**
 * Getter for member MaxEqualUpdatesInSuccession.
 * @return Value of MaxEqualUpdatesInSuccession.
 */
int Service::get_max_equal_updates_in_succession() const
{
    return MaxEqualUpdatesInSuccession;
}


/**
 * Get a unique service identify string
 * @return A unique service identify string
 */
string Service::get_service_name() const
{
    string service_name;

    service_name.append(Protocol);
    service_name.append(" ");
    service_name.append(Hostname);

    return service_name;
}


/**
 * Get member DNSCacheTTL
 * @return DNSCacheTTL
 */
int Service::get_dns_cache_ttl() const
{
    return DNSCacheTTL;
}


/**
 * Set member DNSCacheTTL
 * @param _dns_cache_ttl DNSCacheTTL
 */
void Service::set_dns_cache_ttl(const int _dns_cache_ttl)
{
    DNSCacheTTL = _dns_cache_ttl;
}


/**
 * Get member Activated
 * @return Activated
 */
bool Service::get_activated() const
{
    return Activated;
}


/**
 * Set member Activated
 * @param _activated Activated
 */
void Service::set_activated()
{
    Activated = true;
}