#ifndef __LL_H
#define __LL_H

#include <libubox/avl.h>
#include <netinet/in.h>

struct device;
struct device_user;
struct device_hotplug_ops;

typedef int (*device_state_cb)(struct device *, bool up);

enum {
	DEV_ATTR_TYPE,
	DEV_ATTR_IFNAME,
	DEV_ATTR_MTU,
	DEV_ATTR_MACADDR,
	DEV_ATTR_TXQUEUELEN,
	__DEV_ATTR_MAX,
};

enum dev_change_type {
	DEV_CONFIG_NO_CHANGE,
	DEV_CONFIG_APPLIED,
	DEV_CONFIG_RECREATE,
};

struct device_type {
	struct list_head list;
	const char *name;

	const struct config_param_list *config_params;

	struct device *(*create)(const char *name, struct blob_attr *attr);
	void (*config_init)(struct device *);
	enum dev_change_type (*reload)(struct device *, struct blob_attr *);
	void (*dump_info)(struct device *, struct blob_buf *buf);
	void (*dump_stats)(struct device *, struct blob_buf *buf);
	int (*check_state)(struct device *);
	void (*free)(struct device *);
};

enum {
	DEV_OPT_MTU		= (1 << 0),
	DEV_OPT_MACADDR		= (1 << 1),
	DEV_OPT_TXQUEUELEN	= (1 << 2)
};

/* events broadcasted to all users of a device */
enum device_event {
	DEV_EVENT_ADD,
	DEV_EVENT_REMOVE,

	DEV_EVENT_SETUP,
	DEV_EVENT_TEARDOWN,
	DEV_EVENT_UP,
	DEV_EVENT_DOWN,

	DEV_EVENT_LINK_UP,
	DEV_EVENT_LINK_DOWN,
};

/*
 * device dependency with callbacks
 */
struct device_user {
	struct list_head list;

	bool claimed;
	bool hotplug;

	struct device *dev;
	void (*cb)(struct device_user *, enum device_event);
};

/* 
 * link layer device. typically represents a linux network device.
 * can be used to support VLANs as well
 */
struct device {
	const struct device_type *type;

	struct avl_node avl;
	struct list_head users;

	char ifname[IFNAMSIZ + 1];
	int ifindex;

	struct blob_attr *config;
	bool config_pending;
	bool present;
	int active;
	bool external;

	bool current_config;
	bool default_config;

	/* set interface up or down */
	device_state_cb set_state;

	const struct device_hotplug_ops *hotplug_ops;

	struct device_user parent;

	/* settings */
	unsigned int flags;

	unsigned int mtu;
	unsigned int txqueuelen;
	uint8_t macaddr[6];
};

struct device_hotplug_ops {
	int (*add)(struct device *main, struct device *member);
	int (*del)(struct device *main, struct device *member);
};

extern const struct config_param_list device_attr_list;
extern const struct device_type simple_device_type;
extern const struct device_type bridge_device_type;

void device_lock(void);
void device_unlock(void);

struct device *device_create(const char *name, const struct device_type *type,
			     struct blob_attr *config);
void device_init_settings(struct device *dev, struct blob_attr **tb);
void device_init_pending(void);

enum dev_change_type
device_set_config(struct device *dev, const struct device_type *type,
		  struct blob_attr *attr);

void device_reset_config(void);
void device_reset_old(void);

void device_init_virtual(struct device *dev, const struct device_type *type, const char *name);
int device_init(struct device *iface, const struct device_type *type, const char *ifname);
void device_cleanup(struct device *iface);
struct device *device_get(const char *name, int create);
void device_add_user(struct device_user *dep, struct device *iface);
void device_remove_user(struct device_user *dep);

void device_set_present(struct device *dev, bool state);
int device_claim(struct device_user *dep);
void device_release(struct device_user *dep);
int device_check_state(struct device *dev);
void device_dump_status(struct blob_buf *b, struct device *dev);

static inline void
device_free(struct device *dev)
{
	dev->type->free(dev);
}

void device_free_unused(struct device *dev);

struct device *get_vlan_device_chain(const char *ifname, bool create);
void alias_notify_device(const char *name, struct device *dev);

#endif