/*
 * FreeRTOS+TCP V2.2.2
 * Copyright (C) 2017 Amazon.com, Inc. or its affiliates.  All Rights Reserved.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy of
 * this software and associated documentation files (the "Software"), to deal in
 * the Software without restriction, including without limitation the rights to
 * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
 * the Software, and to permit persons to whom the Software is furnished to do so,
 * subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
 * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
 * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
 * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 *
 * http://aws.amazon.com/freertos
 * http://www.FreeRTOS.org
 */

#ifndef FREERTOS_DHCP_H
#define FREERTOS_DHCP_H

#ifdef __cplusplus
extern "C" {
#endif

/* Application level configuration options. */
#include "FreeRTOSIPConfig.h"
#include "IPTraceMacroDefaults.h"

#if( ipconfigUSE_DHCP_HOOK != 0 )
	/* Used in the DHCP callback if ipconfigUSE_DHCP_HOOK is set to 1. */
	typedef enum eDHCP_PHASE
	{
		eDHCPPhasePreDiscover,	/* Driver is about to send a DHCP discovery. */
		eDHCPPhasePreRequest	/* Driver is about to request DHCP an IP address. */
	} eDHCPCallbackPhase_t;

	/* Used in the DHCP callback if ipconfigUSE_DHCP_HOOK is set to 1. */
	typedef enum eDHCP_ANSWERS
	{
		eDHCPContinue,			/* Continue the DHCP process */
		eDHCPUseDefaults,		/* Stop DHCP and use the static defaults. */
		eDHCPStopNoChanges,		/* Stop DHCP and continue with current settings. */
	} eDHCPCallbackAnswer_t;
#endif	/* #if( ipconfigUSE_DHCP_HOOK != 0 ) */

/* DHCP state machine states. */
typedef enum
{
	eWaitingSendFirstDiscover = 0,	/* Initial state.  Send a discover the first time it is called, and reset all timers. */
	eWaitingOffer,					/* Either resend the discover, or, if the offer is forthcoming, send a request. */
	eWaitingAcknowledge,			/* Either resend the request. */
	#if( ipconfigDHCP_FALL_BACK_AUTO_IP != 0 )
		eGetLinkLayerAddress,		/* When DHCP didn't respond, try to obtain a LinkLayer address 168.254.x.x. */
	#endif
	eLeasedAddress,					/* Resend the request at the appropriate time to renew the lease. */
	eNotUsingLeasedAddress			/* DHCP failed, and a default IP address is being used. */
} eDHCPState_t;

/* Hold information in between steps in the DHCP state machine. */
struct xDHCP_DATA
{
	uint32_t ulTransactionId;
	uint32_t ulOfferedIPAddress;
	uint32_t ulDHCPServerAddress;
	uint32_t ulLeaseTime;
	/* Hold information on the current timer state. */
	TickType_t xDHCPTxTime;
	TickType_t xDHCPTxPeriod;
	/* Try both without and with the broadcast flag */
	BaseType_t xUseBroadcast;
	/* Maintains the DHCP state machine state. */
	eDHCPState_t eDHCPState;
};

typedef struct xDHCP_DATA DHCPData_t;

/*
 * NOT A PUBLIC API FUNCTION.
 */
void vDHCPProcess( BaseType_t xReset );

/* Internal call: returns true if socket is the current DHCP socket */
BaseType_t xIsDHCPSocket( Socket_t xSocket );

#if( ipconfigUSE_DHCP_HOOK != 0 )
	/* Prototype of the hook (or callback) function that must be provided by the
	application if ipconfigUSE_DHCP_HOOK is set to 1.  See the following URL for
	usage information:
	http://www.FreeRTOS.org/FreeRTOS-Plus/FreeRTOS_Plus_TCP/TCP_IP_Configuration.html#ipconfigUSE_DHCP_HOOK
	*/
	eDHCPCallbackAnswer_t xApplicationDHCPHook( eDHCPCallbackPhase_t eDHCPPhase, uint32_t ulIPAddress );
#endif	/* ( ipconfigUSE_DHCP_HOOK != 0 ) */

#ifdef __cplusplus
}	/* extern "C" */
#endif

#endif /* FREERTOS_DHCP_H */