# This file is part of bish-bosh. It is subject to the licence terms in the COPYRIGHT file found in the top-level directory of this distribution and at https://raw.githubusercontent.com/raphaelcohn/bish-bosh/master/COPYRIGHT. No part of bish-bosh, including this file, may be copied, modified, propagated, or distributed except according to the terms contained in the COPYRIGHT file.
# Copyright © 2014-2015 The developers of bish-bosh. See the COPYRIGHT file in the top-level directory of this distribution and at https://raw.githubusercontent.com/raphaelcohn/bish-bosh/master/COPYRIGHT.


core_dependency_oneOf '*' date
bishbosh_connection_ping_initialise()
{
	bishbosh_connection_ping_responsePending=0
	
	if core_variable_isUnset bishbosh_connect_keepAlive; then
		bishbosh_connect_keepAlive=0
	fi
	
	if [ $bishbosh_connect_keepAlive -ne 0 ]; then
	
		if [ $bishbosh_readLatency -ge 1000 ]; then
			if [ $bishbosh_connect_keepAlive -lt 2 ]; then
				core_message WARN "When the option '--read-latency' (or configuration setting 'bishbosh_readLatency') is 1000 ms, 'bishbosh_connect_keepAlive' must be at least 2 seconds (not '$bishbosh_connect_keepAlive'). bishbosh_connect_keepAlive is being forcing to 2 seconds."
				bishbosh_connect_keepAlive=2
			fi
		fi
		
		bishbosh_connection_ping_sendPingIfRequired()
		{
			if [ $bishbosh_connection_ping_responsePending -eq 1 ]; then
				return 0
			fi
			
			if bishbosh_connection_ping_checkTimer -lt $bishbosh_connect_keepAlive; then
				return 0
			fi
			
			core_message INFO 'Writing PINGREQ'
			bishbosh_connection_write_PINGREQ
			bishbosh_connection_ping_responsePending=1
		}
		
		bishbosh_connection_ping_recordLastSentControlPacketAt()
		{
			# Avoid unnecessary resets - speeds up dash, etc shells lacking $SECONDS builtin
			if [ $bishbosh_connection_ping_responsePending -eq 1 ]; then
				return 0
			fi
	
			bishbosh_connection_ping_resetTimer
		}

		bishbosh_connection_ping_checkForResponseTimeout()
		{
			if [ $bishbosh_connection_ping_responsePending -eq 0 ]; then
				return 0
			fi

			if bishbosh_connection_ping_checkTimer -gt $bishbosh_pingTimeout; then
				bishbosh_connection_error_pingTimeout
			fi
		}

		bishbosh_connection_ping_responseReceived()
		{
			core_message INFO 'Received valid PINGRESP'
			bishbosh_connection_ping_responsePending=0
		}
		
		if core_variable_isSet SECONDS; then
			
			bishbosh_connection_ping_resetTimer()
			{
				SECONDS=0
			}

			bishbosh_connection_ping_checkTimer()
			{
				[ $SECONDS $1 $2 ]
			}
			
			return 0
		fi
		
		if core_compatibility_whichNoOutput date; then
		
			_bishbosh_connection_ping_timer=0
			
			bishbosh_connection_ping_resetTimer()
			{
				_bishbosh_connection_ping_timer=$(date '+%s')
			}

			bishbosh_connection_ping_checkTimer()
			{
				local now=$(date '+%s')
				local elapsedTime=$((now-_bishbosh_connection_ping_timer))
				[ $elapsedTime $1 $2 ]
			}
			
			return 0
		fi
		
		core_message WARN "Your shell does not support 'SECONDS' and the 'date' program isn't unavailble. Overriding your setting of 'bishbosh_connect_keepAlive as '$bishbosh_connect_keepAlive' to '0' (ie disabling)."
		bishbosh_connect_keepAlive=0
	fi
	
	bishbosh_connection_ping_sendPingIfRequired()
	{
		:
	}

	bishbosh_connection_ping_recordLastSentControlPacketAt()
	{
		:
	}
	
	bishbosh_connection_ping_checkForResponseTimeout()
	{
		:
	}
	
	bishbosh_connection_ping_responseReceived()
	{
		bishbosh_connection_error_protocolReadControlPacket PINGRESP 'Pings should not be received when Keep Alive is 0'
	}
	
	bishbosh_connection_write_PINGREQ()
	{
		bishbosh_connection_error_protocol "PINGREQ should not be called when Keep Alive is 0"
	}
}