/**
 * @file include/di/can/net/discover.h
 * @brief DI-Net CAN network discovery
 * @date Oct 17, 2016
 * @author jjacobs
 * @copyright 2016 Dual Inventive Technology Centre B.V.
 *
 * CAN network discovery
 */
#ifndef LIBDI_INCLUDE_DI_CAN_NET_DISCOVER_H_
#define LIBDI_INCLUDE_DI_CAN_NET_DISCOVER_H_

struct di_can_msg;
struct di_can_ctx;
struct di_can_net;

#include <stdbool.h>
#include <di/can/callback.h>

#ifdef __cplusplus
extern "C" {
#endif

/** Callback item for net discover request message */
#define DI_CAN_NET_DISCOVER_CALLBACK_REQUEST_ITEM { \
	DI_CAN_CALLBACK_CANID(                      \
		DI_CAN_MSGTYPE_NET,                 \
		DI_CAN_TRANSFERTYPE_REQUEST,        \
		DI_CAN_NET_DTYPE_DISCOVER           \
	),                                          \
	di_can_net_discover_cb                      \
}

/** Callback item for net discover reply message */
#define DI_CAN_NET_DISCOVER_CALLBACK_REPLY_ITEM { \
	DI_CAN_CALLBACK_CANID(                    \
		DI_CAN_MSGTYPE_NET,               \
		DI_CAN_TRANSFERTYPE_REPLY,        \
		DI_CAN_NET_DTYPE_DISCOVER         \
	),                                        \
	di_can_net_discover_cb                    \
}

/** Network discovery states */
enum di_can_net_discover_state {
	DI_CAN_NET_DISCOVER_STATE_UNKNOWN, /**< Network not discovered yet */
	DI_CAN_NET_DISCOVER_STATE_REQUEST, /**< Network discover request send */
	DI_CAN_NET_DISCOVER_STATE_FINISH   /**< Network discover finished */
};

/**
 * Send broadcast discover request
 * @note Discover state is not updated, as this is handled by di_can_net_discover_fsm
 * @param ctx CAN context
 * @return DNOK when discovery is sent
 */
di_errno_t di_can_net_discover(struct di_can_ctx *ctx);

/**
 * Callback for discover request/reply messages handling
 * * Request message will send a reply and updates it local state based on the request
 * * Reply message will update its local state
 * @param msg Request or reply discover message
 * @param ctx CAN context
 */
void di_can_net_discover_cb(const struct di_can_msg *msg, struct di_can_ctx *ctx);

/**
 * Execute the discover FSM
 * * Network node discover
 *   * When DISCOVER_STATE_UNKNOWN -> ping request is send
 *   * When DISCOVER_STATE_REQUEST -> reply timeout exceed
 *   * When DISCOVER_STATE_FINISH  -> network discovery finished
 * * When DISCOVER_STATE_FINISH
 *   * Update leader nodes of same type (last seen)
 *   * Fire a di_can_net_node_event when leader node is offline
 * @note Subsystem must be locked before calling
 */
void di_can_net_discover_fsm(struct di_can_ctx *ctx);

/**
 * Check if the network is discovered
 */
bool di_can_net_is_discovered(struct di_can_ctx *ctx);

#ifdef __cplusplus
}
#endif

#endif /* LIBDI_INCLUDE_DI_CAN_NET_DISCOVER_H_ */