/****************************************************************************

Copyright(c) 2019 by Aerospace C.Power (Chongqing) Microelectronics. ALL RIGHTS RESERVED.

This Information is proprietary to Aerospace C.Power (Chongqing) Microelectronics and MAY NOT
be copied by any method or incorporated into another program without
the express written consent of Aerospace C.Power. This Information or any portion
thereof remains the property of Aerospace C.Power. The Information contained herein
is believed to be accurate and Aerospace C.Power assumes no responsibility or
liability for its use in any way and conveys no license or title under
any patent or copyright and makes no representation or warranty that this
Information is free from patent or copyright infringement.

****************************************************************************/

/* os shim includes */
#include "os_types.h"
#include "os_lock.h"

/* common includes */
#include "iot_errno.h"
#include "iot_module.h"
#include "iot_queue.h"

uint32_t iot_msg_queue_init(iot_msg_queue_t *queue)
{
    uint32_t ret = 0;

    queue->lock = os_create_mutex(IOT_QUEUE_MID);
    if (queue->lock == NULL) {
        ret = ERR_NOMEM;
        goto out;
    }

    queue->cnt = 0;
    queue->head = NULL;
    queue->tail = NULL;

out:
    return ret;
}

void iot_msg_queue_deinit(iot_msg_queue_t *queue)
{
    IOT_ASSERT(queue->head == NULL && queue->tail == NULL);
    IOT_ASSERT(queue->cnt == 0);
    IOT_ASSERT(queue->lock);

    os_delete_mutex(queue->lock);
    queue->lock = NULL;
}

void iot_msg_queue_put(iot_msg_queue_t *queue, iot_msg_entry_t *msg)
{
    IOT_ASSERT(queue->lock);

    os_acquire_mutex(queue->lock);
    IOT_ASSERT(msg->next == NULL);
    if (queue->head == NULL) {
        IOT_ASSERT(queue->tail == NULL);
        queue->head = msg;
    }
    if (queue->tail) {
        IOT_ASSERT(queue->head);
        queue->tail->next = msg;
    }
    queue->tail = msg;
    queue->cnt++;
    os_release_mutex(queue->lock);
}

iot_msg_entry_t *iot_msg_queue_get(iot_msg_queue_t *queue)
{
    iot_msg_entry_t *entry = NULL;

    IOT_ASSERT(queue->lock);

    os_acquire_mutex(queue->lock);
    if (queue->head) {
        IOT_ASSERT(queue->tail);
        queue->cnt--;
        entry = queue->head;
        if (queue->head == queue->tail) {
            queue->head = NULL;
            queue->tail = NULL;
        } else {
            queue->head = queue->head->next;
        }
        entry->next = NULL;
    } else {
        IOT_ASSERT(queue->tail == NULL);
    }
    os_release_mutex(queue->lock);

    return entry;
}

void iot_msg_queue_loop(iot_msg_queue_t *queue, iot_msg_queue_loop_func_t func,
    void *param)
{
    iot_msg_entry_t *prev = NULL, *curr = NULL, *next = NULL;

    IOT_ASSERT(queue->lock);

    os_acquire_mutex(queue->lock);
    curr = queue->head;
    while (curr) {
        next = curr->next;
        if (func(curr, param)) {
            queue->cnt--;
            if (prev) {
                prev->next = next;
            } else {
                queue->head = next;
            }
            if (queue->tail == curr) {
                queue->tail = prev;
            }
        } else {
            prev = curr;
        }
        curr = next;
    }
    os_release_mutex(queue->lock);
}