/**
 * @file Ems_object.c
 * @author your name (you@domain.com)
 * @brief
 * @version 0.1
 * @date 2023-04-05
 *
 * @copyright Copyright (c) 2023
 *
 */

/* includes ----------------------------------------------------------------- */
#include <string.h>
#include "ems_object.h"
#include "ems_assert.h"

/* private variables -------------------------------------------------------- */
static ems_object_t *ems_list = NULL;

/* public functions --------------------------------------------------------- */
/**
 * @brief
 *
 * @param me
 * @param name
 * @param ops
 * @param attr
 */
void ems_register(ems_object_t *const me, const char *name,
                  const ems_ops_t *ops,
                  ems_obj_attr_t *attr)
{
    ems_assert(me != NULL);
    ems_assert(name != NULL);
    ems_assert(ops != NULL);
    ems_assert(attr != NULL);

    me->name = name;
    me->ops = ops;

    me->next = ems_list;
    ems_list = me;

    memcpy(&me->attr, attr, sizeof(ems_obj_attr_t));
}

/**
 * @brief
 *
 * @param name
 * @return ems_object_t*
 */
ems_object_t *ems_find(const char *name)
{
    ems_assert(name != NULL);
    ems_object_t *obj = ems_list;
    while (obj != NULL)
    {
        if (strcmp(obj->name, name) == 0)
        {
            break;
        }
        obj = obj->next;
    }

    return obj;
}

/**
 * @brief 
 * 
 * @param me 
 * @return ems_err_t 
 */
ems_err_t ems_open(ems_object_t *const me)
{
    ems_assert(me->ops->open != NULL);

    ems_err_t ret = EMS_OK;

    if (me->attr.standlone)
    {
        if (me->count_open != 0)
        {
            ret = EMS_ERROR;
            goto exit;
        }
    }

    ret = me->ops->open(me);
    if (ret == EMS_OK)
    {
        me->count_open++;
    }

exit:
    return ret;
}

/**
 * @brief 
 * 
 * @param me 
 * @return ems_err_t 
 */
ems_err_t ems_close(ems_object_t *const me)
{
    ems_assert(me->ops->close != NULL);

    ems_err_t ret = EMS_OK;

    if (me->count_open > 0)
    {
        ret = me->ops->close(me);
        if (ret == EMS_OK)
        {
            me->count_open--;
            goto exit;
        }
    }
    else
    {
        ret = EMS_ERROR;
    }

exit:
    return ret;
}

/**
 * @brief 
 * 
 * @param me 
 * @param buffer 
 * @param size 
 * @return int32_t 
 */
int32_t ems_read(ems_object_t *const me, void *buffer, uint32_t size)
{
    ems_assert(me != NULL);
    ems_assert(buffer != NULL);
    ems_assert(size != 0);
    ems_assert(me->ops->read != NULL);

    int32_t ret = 0;

    if (me->count_open != 0)
    {
        ret = me->ops->read(me, buffer, size);
    }
    else
    {
        ret = (int32_t)EMS_ERROR;
    }

    return ret;
}

/**
 * @brief 
 * 
 * @param me 
 * @param buffer 
 * @param size 
 * @return int32_t 
 */
int32_t ems_write(ems_object_t *const me, const void *buffer, uint32_t size)
{
    ems_assert(me != NULL);
    ems_assert(buffer != NULL);
    ems_assert(size != 0);
    ems_assert(me->ops->write != NULL);

    int32_t ret = 0;

    if (me->count_open != 0)
    {
        ret = me->ops->write(me, buffer, size);
    }
    else
    {
        ret = (int32_t)EMS_ERROR;
    }

    return ret;
}