/*
 * HS X.25 Protocol Stack. Developed by Hillstone Software (http://www.hillstone-software.com)
 */
#ifndef _HS_X25_API_H
#define _HS_X25_API_H

#define HS_MAX_NUA		15		// max NUA length
#define HS_MAX_FAC		255		// max facility length
#define HS_MAX_CUD		128		// max call user data length

typedef enum
{
	T20TMR,
	T21TMR,
	T22TMR,
	T23TMR,
	T10TMR,
	T11TMR,
	T12TMR,
	T13TMR,
} hs_x25_tid_t;

typedef enum
{
	HS_X25_RC_OK,					// success
	HS_X25_RC_NOLINK,				// could not allocate new l2 link
	HS_X25_RC_NO_VC,				// no free vc available
	HS_X25_RC_DL_INIT_FAIL,			// data link layer init failed
	HS_X25_RC_INV_PAR,				// invalid parameters
	HS_X25_RC_TOO_LONG,				// packet too long
	HS_X25_RC_DL_LIS_FAIL,			// DL Listen failed
	HS_X25_RC_TXQ_FULL,				// Transmit queue is full
	HS_X25_RC_INV_PKTSIZE,			// Invalid packet size
	HS_X25_RC_INV_WSIZE,			// invalid window size
	
	HS_X25_RC_TX_PENDING,
	HS_X25_RC_FAIL,
	HS_X25_RC_BUF_TOO_BIG,
} hs_x25_rc_t;

typedef enum
{
	HS_X25_EV_CONN_FAIL_PKTLR,					// Connect failed, packet layer not ready
	HS_X25_EV_PKTLR_DOWN,						// Packet layer down as result of physical layer down
	HS_X25_EV_PKTLR_RESTARTED,					// Packet layer restarted (result of restart from the line)
	HS_X25_EV_CALL_CONNECTED,					// X.25 SVC connected
	HS_X25_EV_CALL_CLEAR_COMPLETE,				// X.25 SVC clearing completed
	HS_X25_EV_CALL_CLEARED,						// X.25 SVC cleared by network
	HS_X25_EV_DATA,								// X.25 data received
	HS_X25_EV_DATA_EXP,							// X.25 Expedited data received
	HS_X25_EV_EXP_DATA_TX_FAIL,					// cannot send expedited data, previous exp data not acknowledged
	HS_X25_EV_EXP_DATA_DELIVERED,				// expedited data delivered to remote end
	HS_X25_EV_CALL_CLEARED_T13,					// X.25 SVC cleared - no answer to call indication
	HS_X25_EV_BUF_TX_FAIL,						// buffer not transmitted and must be released
	HS_X25_EV_INCOMING_CALL_CONNECTED,			// incoming call connected (HsX25Listen completed)
} hs_x25_ev_t;

typedef void hs_x25_timer_callback_t(long handle);

/*
 * Start timer
 * handle - HsX25 handle
 * secs - timeout in seconds
 * callback - timer expired callback address (function in HsX25 code)
 * tid - timer id
 * return - timer handle
 */
typedef long hs_x25_start_timer_t(long handle, unsigned long secs, hs_x25_timer_callback_t *callback, int tid);

/* 
 * Stop Timer
 * handle - timer handle
 * tid - timer id
 */
typedef void hs_x25_stop_timer_t(long handle, int tid);

typedef void hs_x25_event_callback_t(long handle, int ev, long arg1, long arg2);

typedef struct
{
	hs_x25_start_timer_t	*start_timer;
	hs_x25_stop_timer_t		*stop_timer;
	hs_x25_event_callback_t	*event_cb;
} hs_x25_api_t;

typedef enum
{
	HS_X25_OPT_NORMAL 		=0,
	HS_X25_OPT_L2_LOOP		=1,
} hs_x25_opt_t;

typedef void hs_trace_cb_t(int is_rx, unsigned char *buf, int len, long arg);

typedef struct
{
	hs_x25_api_t			api;
	int						opt;
	int						is_rfc1613;	// 1=CISCO mode XOT, 0=Proprietory bridge mode XOT
	unsigned char			*rfc1613_peer_ip;
	int						is_dce;
	int						pktsize;
	int						wsize;
	hs_trace_cb_t			*trc_fn;
	int						hi_incoming_lcn;	// high LCN for incoming calls
	int						lo_incoming_lcn;	// low LCN for incoming calls
	int						support_dbit;		// set D bit ON in call accept
} hs_x25_init_t;

/* configuration structure */
typedef struct
{
	int						t10_val;
	int						t11_val;
	int						t12_val;
	int						t13_val;
	int						t20_val;
	int						t20_retry;
	int						t21_val;
	int						t22_val;
	int						t23_val;

	int						pktsize;			// configured packet size in bytes (size of DATA payload)
	int						wsize;				// configured window size

	int						hi_incoming_lcn;	// high LCN for incoming calls
	int						lo_incoming_lcn;	// low LCN for incoming calls
	int						support_dbit;		// set D bit ON in call accept
} hs_x25_cfg_t;

typedef struct
{
	long					l2_addr;
	long					arg;
	
	unsigned char			called[HS_MAX_NUA+1];
	unsigned char			calling[HS_MAX_NUA+1];
	
	unsigned char			facility_buf[HS_MAX_FAC];
	unsigned char			facility_len;

	unsigned char			call_user_data[HS_MAX_CUD];
	int						cud_len;
	
	int						dbit;
} hs_x25_conn_t;

/* listen structure */
typedef struct
{
	long					l2_addr;				// link identifier
	long					arg;					// in case of XOT, listening TCP port number

	int						take_any_call;			// if this flag is set, addresses below are ignored and any call is accepted
	
	unsigned char			called[HS_MAX_NUA];		// one byte per digit, e.g 0x31 0x32 0x33 etc
	int						called_len;				// called address length
	unsigned char			calling[HS_MAX_NUA];	// one byte per digit, e.g 0x31 0x32 0x33 etc
	int						calling_len;			//calling address length
} hs_x25_listen_t;

/* data structure */
typedef struct
{
	unsigned char *bufp;
	int			len;	
} hs_x25data_t;

typedef struct 
{
	int			lci;
	int			pti;
	unsigned char *pkt;
	int			len;
	int			Pr;
	int			Ps;
	unsigned char *pktname;
} hs_x25_pkt_info_t;

typedef enum
{
	HS_X25_RC_DECODE_UNSPEC,						// unspecified error
	HS_X25_RC_DECODE_OK,							// packet decode correct
	HS_X25_RC_DECODE_SHORT,							// packet too short
	HS_X25_RC_DECODE_INV_GFI,						// invalid GFI or PTI
	HS_X25_RC_DECODE_LCI_UNASSIGN,					// packet on unassigned logical channel
	HS_X25_RC_DECODE_LONG,							// packet too long
} hs_x25_packet_decode_err_t;

typedef enum
{
	/* events coming from above (user app) */
	HS_X25_CONNECT,									// user request to establish outgoing call
	HS_X25_LISTEN,									// user request to listen for incoming call
	HS_X25_DATA,									// send data packet
	HS_X25_DATA_EXP,								// send expedited data (bypass flow control)
	HS_X25_DISCONNECT,								// disconnect call from user

	/* data link related events */
	HS_X25_DL_RELEASE,								// data link disconnected
	HS_X25_DL_CONNECT,								// data link is up
	HS_X25_DL_DATA,									// data received from data link

	/* events generated based on reception from the line */
	HS_X25_CALL_ACCEPTED,							// call connected or call acepted
	HS_X25_CALL_REQ,								// call request or call indication
	HS_X25_RESTART_REQ,								// restart request or restart indication
	HS_X25_RESTART_CNF,								// restart confirmation
	HS_X25_RR,										// receiver ready
	HS_X25_RNR,										// receiver not ready
	HS_X25_DAT,										// data from line
	HS_X25_CLEAR_CNF,								// clear confirmation from line
	HS_X25_CLEAR_REQ,								// clear request or indication from line
	HS_X25_INT_CNF,									// interrupt confirmation from line
	HS_X25_INT_REQ,									// interrupt request or indication from line
	HS_X25_RESET_REQ,								// reset request or indications from line
	HS_X25_RESET_CNF,								// reset confirm from line

	/* internal */
	HS_X25_TICK,

	HS_X25_RNR_CONDITON,							// set or clear RNR condition
	
} hs_x25_fsm_events_t;

typedef struct
{
	long		data;
	long		rr;
	long		rnr;
	long		reset;
	long		intr;
} tx_rx_t;

typedef struct 
{
	int			lci;
	tx_rx_t		tx;
	tx_rx_t		rx;
	unsigned	char *st;
	int			w;
} hs_x25_stats_t;

/*
 * Initialise HS X.25 Protocol
 */
extern int HsX25Init(hs_x25_init_t *init);

/*
 * Initiate outgoing X.25 call
 */
extern int HsX25Connect(hs_x25_conn_t *conn, long *handle, int *lci);

/*
 * Submit a listen request for incoming X.25 call
 */
extern int HsX25Listen(hs_x25_listen_t *listen);

/*
 * Clear X.25 Call
 */
extern int HsX25Clear(long handle);

/*
 * Send X.25 Data sequence
 */
extern int HsX25Data(long handle, unsigned char *buf, int len, int qbit);

/*
 * Send expedited data (Interrupt)
 */
extern int HsX25DataExp(long handle, unsigned char *buf, int len);

/*
 * Send RNR (signal receiver not ready)
 */
extern int HsX25Rnr(long handle, int on);

extern int HsX25Tick(void);

/*
 * Flush listen queue
 */
extern int HsX25FlushListenQueue(long l2_addr);

/*
 * Close all interfaces
 */
extern void HsX25ShutDown(void);

/*
 * Configure X.25 Stack
 */
extern int HsX25Config(hs_x25_cfg_t *cfg);

extern int HsX25DecodePkt(unsigned char *pkt, int len, int *ev, hs_x25_pkt_info_t *info, int need_name);

extern void HsX25GetStats(long handle, hs_x25_stats_t *stats);

#endif /* _HS_X25_API_H */