#ifndef REPLICATOR_QUEUE_H
#define REPLICATOR_QUEUE_H

#include "priorityq.h"
#include "replication-common.h"

struct replicator_user {
	struct priorityq_item item;

	char *username;
	/* dsync state for incremental syncing */
	char *state;
	/* last time this user's state was updated */
	time_t last_update;
	/* last_fast_sync is always >= last_full_sync. */
	time_t last_fast_sync, last_full_sync, last_successful_sync;

	int refcount;
	enum replication_priority priority;
	/* User isn't currently in replication queue */
	bool popped:1;
	/* Last replication sync failed */
	bool last_sync_failed:1;
	/* Force a full sync on the next replication */
	bool force_full_sync:1;
};

typedef void replicator_sync_callback_t(bool success, void *context);

struct replicator_queue *
replicator_queue_init(unsigned int full_sync_interval,
		      unsigned int failure_resync_interval);
void replicator_queue_deinit(struct replicator_queue **queue);

/* Call the specified callback when data is added/removed/moved in queue
   via _add(), _add_sync() or _remove() functions (not push/pop). */
void replicator_queue_set_change_callback(struct replicator_queue *queue,
					  void (*callback)(void *context),
					  void *context);

/* Reference the user */
void replicator_user_ref(struct replicator_user *user);
/* Unreference the user. Returns TRUE if refcount is still >0. */
bool replicator_user_unref(struct replicator_user **user);

/* Lookup an existing user */
struct replicator_user *
replicator_queue_lookup(struct replicator_queue *queue, const char *username);
/* Lookup or create a user and return it. Afterwards replicator_queue_add()
   must be called to add/move the user to the proper place in the queue. */
struct replicator_user *
replicator_queue_get(struct replicator_queue *queue, const char *username);
/* Update user's priority if it's currently lower. */
void replicator_queue_update(struct replicator_queue *queue,
			     struct replicator_user *user,
			     enum replication_priority priority);
void replicator_queue_add(struct replicator_queue *queue,
			  struct replicator_user *user);
/* Call the callback when user with SYNC priority has finished syncing. */
void replicator_queue_add_sync_callback(struct replicator_queue *queue,
					struct replicator_user *user,
					replicator_sync_callback_t *callback,
					void *context);
/* Remove user from replication queue and free it. */
void replicator_queue_remove(struct replicator_queue *queue,
			     struct replicator_user **user);
/* Return the number of users in the queue. */
unsigned int replicator_queue_count(struct replicator_queue *queue);

/* Return the next user from replication queue and how many seconds from now
   the returned user should be synced (0 = immediately). Returns NULL only if
   there are no users in the queue. */
struct replicator_user *
replicator_queue_peek(struct replicator_queue *queue,
		      unsigned int *next_secs_r);
/* Return the next user from replication queue, and remove it from the queue.
   If there's nothing to be replicated currently, returns NULL and sets
   next_secs_r to when there should be more work to do. */
struct replicator_user *
replicator_queue_pop(struct replicator_queue *queue,
		     unsigned int *next_secs_r);
/* Add user back to queue. */
void replicator_queue_push(struct replicator_queue *queue,
			   struct replicator_user *user);

int replicator_queue_import(struct replicator_queue *queue, const char *path);
int replicator_queue_export(struct replicator_queue *queue, const char *path);

/* Returns TRUE if user replication can be started now, FALSE if not. When
   returning FALSE, next_secs_r is set to user's next replication time. */
bool replicator_queue_want_sync_now(struct replicator_user *user,
				    unsigned int *next_secs_r);
/* Iterate through all users in the queue. */
struct replicator_queue_iter *
replicator_queue_iter_init(struct replicator_queue *queue);
struct replicator_user *
replicator_queue_iter_next(struct replicator_queue_iter *iter);
void replicator_queue_iter_deinit(struct replicator_queue_iter **iter);

void replicator_queue_add_auth_users(struct replicator_queue *queue,
				     const char *auth_socket_path,
				     const char *usermask, time_t last_update);

#endif