#include <winpr/synch.h>
#include "precompile.h"

#include "sp_uid.h"

#include "spinlock.h"
#include "memutil.h"
#include "y2k_time.h"
#include "dbgutil.h"

struct sp_uid_generator_t
{
	unsigned short app_id;
	lock_t lock;
	struct _sp_uid_t last_id;
	int mt;
};

sp_uid_generator_t *sp_uid_generator_create(unsigned short app_id, int mt)
{
	sp_uid_generator_t *uid_gen = MALLOC_T(sp_uid_generator_t);
	if (uid_gen) {
		uid_gen->app_id = app_id;
		uid_gen->mt = mt;
		if (mt) {
			fastlock_init(uid_gen->lock);
		}
		uid_gen->last_id.app_id = app_id;
		uid_gen->last_id.dsn = 0;
		uid_gen->last_id.tick = y2k_time_now();
	}
	return uid_gen;
}

void sp_uid_generator_destroy(sp_uid_generator_t *uid)
{
	if (uid->mt) {
		fastlock_term(uid->lock);
	}
	free(uid);
}

sp_uid_t sp_uid_generator_new_id(sp_uid_generator_t *uid)
{
	struct _sp_uid_t r;
	TOOLKIT_ASSERT(uid);
	r.app_id = uid->app_id;
repeat:
	r.tick = y2k_time_now();
	if (uid->mt) {
		fastlock_enter(uid->lock);
	}
	if (r.tick == uid->last_id.tick) {
		r.dsn = uid->last_id.dsn + 1;
		if (r.dsn == 0) {
			if (uid->mt) {
				fastlock_leave(uid->lock);
			}
			Sleep(1);
			goto repeat;
		}
	} else {
		r.dsn = 0;
	}
	uid->last_id.dsn = r.dsn;
	uid->last_id.tick = r.tick;
	if (uid->mt) {
		fastlock_leave(uid->lock);
	}
	return r.id;
}

sp_uid_t sp_uid_make(unsigned short app_id)
{
	struct _sp_uid_t r;
	r.app_id = app_id;
	r.dsn = 0;
	r.tick = y2k_time_now();
	return r.id;
}

sp_uid_t sp_uid_update(sp_uid_t t)
{
	y2k_time_t now;
	struct _sp_uid_t r;
	r.id = t;
repeat:
	now = y2k_time_now();
	if (now == r.tick) {
		r.dsn++;
		if (r.dsn == 0) {
			Sleep(1);
			goto repeat;
		}
	} else {
		r.dsn = 0;
		r.tick = now;
	}
	return r.id;
}