/// ------------------------------------------------------------------------------------------------------------------------------------
///
/// MIT License
///
/// Permission is hereby granted, free of charge, to any person obtaining a copy
/// of this software and associated documentation files (the "Software"), to deal
/// in the Software without restriction, including without limitation the rights
/// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
/// copies of the Software, and to permit persons to whom the Software is
/// furnished to do so, subject to the following conditions:
///
/// The above copyright notice and this permission notice shall be included in all
/// copies or substantial portions of the Software.
///
/// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
/// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
/// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
/// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
/// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
/// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
/// SOFTWARE.
///
/// Copyright (c) 2022 ycz. All rights reserved.
///
/// Created by ycz on 2022/1/12.
///
/// @brief
///     y_ringbuf 具体功能实现
///
/// ------------------------------------------------------------------------------------------------------------------------------------



/// ------------------------------------------------------------------------------------------------------------------------------------
/// 头文件
/// ------------------------------------------------------------------------------------------------------------------------------------

#include "y_ringbuf.h"

#include <stdlib.h>
#include <string.h>
#include "y_log.h"



/// ------------------------------------------------------------------------------------------------------------------------------------
/// 模块功能使能判断
/// ------------------------------------------------------------------------------------------------------------------------------------

#if (USE_Y_RINGBUF == 1)



/// ------------------------------------------------------------------------------------------------------------------------------------
/// 结构体
/// ------------------------------------------------------------------------------------------------------------------------------------

/// ringbuf 实例结构类型
struct ringbuf {
    uint8_t *buf;        ///< ringbuf 指针
    uint16_t length;     ///< ringbuf 大小 最大64k
    uint16_t head;       ///< ringbuf 头所在位置
    uint16_t tail;       ///< ringbuf 尾所在位置
    uint16_t used_size;  ///< ringbuf 已使用大小
    uint16_t free_size;  ///< ringbuf 空闲大小
#    if Y_RINGBUF_USE_MUTEX_LOCK == 1
    int32_t mutex_lock;  ///< 互斥锁句柄
#    endif
};



/// ------------------------------------------------------------------------------------------------------------------------------------
/// 私有函数
/// ------------------------------------------------------------------------------------------------------------------------------------

#    if Y_RINGBUF_USE_MUTEX_LOCK == 1
/// @brief ringbuf 上锁
/// @param [in]  ringbuf    ringbuf 句柄指针
/// @retval true  成功
/// @retval false 失败
static bool _y_ringbuf_lock(RINGBUF_st *ringbuf) {
    // todo : 添加代码
    return true;
}

/// @brief ringbuf 解锁
/// @param [in]  ringbuf    ringbuf 句柄指针
/// @retval true  成功
/// @retval false 失败
static bool _y_ringbuf_unlock(RINGBUF_st *ringbuf) {
    // todo : 添加代码
    return true;
}

/// @brief 销毁互斥锁
/// @param [in]  ringbuf    ringbuf 句柄指针
/// @retval true  成功
/// @retval false 失败
static bool _y_ringbuf_destroy_mutex_lock(RINGBUF_st *ringbuf) {
    // todo : 添加代码
    return true;
}

/// @brief 创建互斥锁
/// @param [in]  ringbuf    ringbuf 句柄指针
/// @retval true  成功
/// @retval false 失败
static bool _y_ringbuf_create_mutex_lock(RINGBUF_st *ringbuf) {
    // todo : 添加代码
    return true;
}
#    endif  // Y_RINGBUF_USE_MUTEX_LOCK

/// @brief ringbuf read 子函数
/// @param [in]  ringbuf    ringbuf 句柄指针
/// @param [out] data       读到数据存放的地址
/// @param [in]  size       想要读取的字节数
/// @param [in]  clear_data 读取后是否清除 buf 中的数据 true:清除  false:不清除
/// @return  实际读到的字节数（\<=size)
static uint16_t _y_ringbuf_read_sub(RINGBUF_st *ringbuf, uint8_t *data, uint16_t size, bool clear_data) {

    // 断言
    if (ringbuf == NULL) {
        YLOGE("ringbuf is NULL");
        return 0;
    }
    if (data == NULL && size != 0) {
        YLOGE("data pointer is NULL ,but size != 0 is %d", size);
        return 0;
    }

#    if Y_RINGBUF_USE_MUTEX_LOCK == 1
    // 上锁
    _y_ringbuf_lock(ringbuf);
#    endif

    uint16_t read_size = 0;

    // 判断是否有数据可读
    if (ringbuf->used_size != 0 && size != 0) {

        // 判断需要可读的大小
        if (ringbuf->used_size >= size) {
            read_size = size;
        } else {
            read_size = ringbuf->used_size;
        }

        // 判断头尾位置 确定读取方式
        if (ringbuf->tail <= ringbuf->head) {

            // 尾在头前面 或 在同一位置(全满)
            uint16_t end_size = ringbuf->length - ringbuf->head;  // 尾部可读的空间
            if (end_size > read_size) {
                // 尾部数据足够读 可以顺序读取
                memcpy(data, ringbuf->buf + ringbuf->head, read_size);
                if (clear_data == true) {
                    ringbuf->head += read_size;
                }
            } else if (end_size == read_size) {
                // 尾部数据刚好够读 可以顺序读取 但头位置移到 buf 开头
                memcpy(data, ringbuf->buf + ringbuf->head, read_size);
                if (clear_data == true) {
                    ringbuf->head = 0;
                }
            } else {
                // 尾部数据不够读 需要分段读取
                memcpy(data, ringbuf->buf + ringbuf->head, end_size);
                memcpy(data + end_size, ringbuf->buf, read_size - end_size);
                if (clear_data == true) {
                    ringbuf->head = read_size - end_size;
                }
            }

        } else {

            // 尾在头后面
            memcpy(data, ringbuf->buf + ringbuf->head, read_size);
            if (clear_data == true) {
                ringbuf->head += read_size;
            }
        }
    }

    // 更新句柄相关状态
    if (clear_data == true) {
        ringbuf->used_size -= read_size;
        ringbuf->free_size += read_size;
    }

#    if Y_RINGBUF_USE_MUTEX_LOCK == 1
    // 解锁
    _y_ringbuf_unlock(ringbuf);
#    endif

    YLOGV("ringbuf read %d succeed", read_size);
    return read_size;
}



/// ------------------------------------------------------------------------------------------------------------------------------------
/// 公有函数
/// ------------------------------------------------------------------------------------------------------------------------------------

/// @brief 打印 y_ringbuf 版本号
void y_ringbuf_print_version() {
    YLOGI("y_ringbuf version : V%d.%d.%d", Y_RINGBUF_VERSION_MAJOR, Y_RINGBUF_VERSION_MINOR, Y_RINGBUF_VERSION_PATCH);
}

/// @brief 获取 ringbuf 中已使用的字节数
/// @param [in] ringbuf  ringbuf 句柄指针
/// @return 已使用的字节数
uint16_t y_ringbuf_get_used_size(RINGBUF_st *ringbuf) {

    // 断言
    if (ringbuf == NULL) {
        YLOGE("ringbuf is NULL");
        return 0;
    }

    return ringbuf->used_size;
}

/// @brief 获取 ringbuf 中剩余可用的字节数
/// @param [in] ringbuf  ringbuf 句柄指针
/// @return 剩余可用的字节数
uint16_t y_ringbuf_get_free_size(RINGBUF_st *ringbuf) {

    // 断言
    if (ringbuf == NULL) {
        YLOGE("ringbuf is NULL");
        return 0;
    }

    return ringbuf->used_size;
}

/// @brief 从 ringbuf 中读取数据后并清除
/// @param [in]  ringbuf  ringbuf 句柄指针
/// @param [out] data     读到数据存放的地址
/// @param [in]  size     想要读取的字节数
/// @return 实际读到的字节数（\<=size)
uint16_t y_ringbuf_read_clear(RINGBUF_st *ringbuf, uint8_t *data, uint16_t size) {
    return _y_ringbuf_read_sub(ringbuf, data, size, true);
}

/// @brief 从 ringbuf 中读取数据但不清除数据
/// @param [in]  ringbuf  ringbuf 句柄指针
/// @param [out] data     读到数据存放的地址
/// @param [in]  size     想要读取的字节数
/// @return 实际读到的字节数（\<=size)
uint16_t y_ringbuf_read_only(RINGBUF_st *ringbuf, uint8_t *data, uint16_t size) {
    return _y_ringbuf_read_sub(ringbuf, data, size, false);
}

/// @brief 写入数据到 ringbuf
/// @param [in] ringbuf  ringbuf 句柄指针
/// @param [in] data     待写入数据指针
/// @param [in] size     待写入数据大小
/// @retval true  成功
/// @retval false 失败
bool y_ringbuf_write(RINGBUF_st *ringbuf, uint8_t *data, uint16_t size) {

    // 断言
    if (ringbuf == NULL) {
        YLOGE("ringbuf is NULL");
        return false;
    }
    if (data == NULL && size != 0) {
        YLOGE("data pointer is NULL ,but size != 0 is %d", size);
        return false;
    }

#    if Y_RINGBUF_USE_MUTEX_LOCK == 1
    // 上锁
    _y_ringbuf_lock(ringbuf);
#    endif

    // 判断空闲空间是否满足写入要求
    if (ringbuf->free_size < size) {
        YLOGD("ringbuf free size %d ,but need write size %d", ringbuf->free_size, size);

#    if Y_RINGBUF_USE_MUTEX_LOCK == 1
        // 解锁
        _y_ringbuf_unlock(ringbuf);
#    endif

        return false;
    }

    // 判断头尾位置 确定写入方式
    if (ringbuf->tail < ringbuf->head) {

        // 尾在头前面 可以直接顺序写入
        memcpy(ringbuf->buf + ringbuf->tail, data, size);
        ringbuf->tail += size;

    } else {

        // 尾在头后面 或 在同一位置(全空)
        uint16_t end_size = ringbuf->length - ringbuf->tail;  // 尾部剩余可用的空间
        if (end_size > size) {
            // 尾部可用空间足够 可以直接顺序写入
            memcpy(ringbuf->buf + ringbuf->tail, data, size);
            ringbuf->tail += size;
        } else if (end_size == size) {
            // 尾部可用空间刚好够 可以直接顺序写入 但尾位置移到 buf 开头
            memcpy(ringbuf->buf + ringbuf->tail, data, size);
            ringbuf->tail = 0;
        } else {
            // 尾部可用空间不足 需要分段写入
            memcpy(ringbuf->buf + ringbuf->tail, data, end_size);
            memcpy(ringbuf->buf, data + end_size, size - end_size);
            ringbuf->tail = size - end_size - 1;
        }
    }

    // 更新句柄相关状态
    ringbuf->used_size += size;
    ringbuf->free_size -= size;

#    if Y_RINGBUF_USE_MUTEX_LOCK == 1
    // 解锁
    _y_ringbuf_unlock(ringbuf);
#    endif

    YLOGV("ringbuf write %d succeed", size);
    return true;
}

/// @brief 删除 ringbuf 中指定长度的数据
/// @param [in] ringbuf  ringbuf 句柄指针
/// @param [in] size     要删除的数据长度
/// @retval true  成功
/// @retval false 失败
bool y_ringbuf_delete_data(RINGBUF_st *ringbuf, uint16_t size) {

    // 断言
    if (ringbuf == NULL) {
        YLOGE("ringbuf is NULL");
        return false;
    }

    // 判断是否有足够的数据可删
    if (ringbuf->used_size < size) {
        YLOGV("not enough data, need delete %d data,but only used size %d", size, ringbuf->used_size);
        return false;
    }

#    if Y_RINGBUF_USE_MUTEX_LOCK == 1
    // 上锁
    _y_ringbuf_lock(ringbuf);
#    endif

    // 判断头尾位置 确定删除方式
    if (ringbuf->tail <= ringbuf->head) {

        // 尾在头前面 或 在同一位置(全满)
        uint16_t end_size = ringbuf->length - ringbuf->head;  // 尾部删除的空间
        if (end_size > size) {
            // 尾部数据足够 可以直接删除
            ringbuf->head += size;
        } else if (end_size == size) {
            // 尾部数据刚好 可以直接删除 但头位置移到 buf 开头
            ringbuf->head = 0;
        } else {
            // 尾部数据不够 需要分段删除
            ringbuf->head = size - end_size;
        }

    } else {

        // 尾在头后面 可以直接删除
        ringbuf->head += size;
    }

    // 更新句柄相关状态
    ringbuf->used_size -= size;
    ringbuf->free_size += size;

#    if Y_RINGBUF_USE_MUTEX_LOCK == 1
    // 解锁
    _y_ringbuf_unlock(ringbuf);
#    endif

    YLOGV("ringbuf delete %d data succeed", size);
    return true;
}

/// @brief 判断 ringbuf 是否为满
/// @param [in] ringbuf ringbuf 句柄指针
/// @retval true  成功
/// @retval false 失败
bool y_ringbuf_is_full(RINGBUF_st *ringbuf) {

    // 断言
    if (ringbuf == NULL) {
        YLOGE("ringbuf is NULL");
        return false;
    }

    if (ringbuf->free_size == 0) {
        return true;
    } else {
        return false;
    }
}

/// @brief 判断 ringbuf 是否为空
/// @param [in] ringbuf ringbuf 句柄指针
/// @retval true  成功
/// @retval false 失败
bool y_ringbuf_is_empty(RINGBUF_st *ringbuf) {

    // 断言
    if (ringbuf == NULL) {
        YLOGE("ringbuf is NULL");
        return false;
    }

    if (ringbuf->used_size == 0) {
        return true;
    } else {
        return false;
    }
}

/// @brief 重置 ringbuf
/// @param [in] ringbuf ringbuf 句柄指针
/// @retval true  成功
/// @retval false 失败
bool y_ringbuf_reset(RINGBUF_st *ringbuf) {

    // 断言
    if (ringbuf == NULL) {
        YLOGE("ringbuf is NULL, ringbuf reset fail");
        return false;
    }

#    if Y_RINGBUF_USE_MUTEX_LOCK == 1
    // 上锁
    _y_ringbuf_lock(ringbuf);
#    endif

    // 句柄状态初始化
    ringbuf->head      = 0;                // ringbuf 头所在位置
    ringbuf->tail      = 0;                // ringbuf 尾所在位置
    ringbuf->used_size = 0;                // ringbuf 已使用大小
    ringbuf->free_size = ringbuf->length;  // ringbuf 空闲大小

#    if Y_RINGBUF_USE_MUTEX_LOCK == 1
    // 解锁
    _y_ringbuf_unlock(ringbuf);
#    endif

    YLOGI("ringbuf %p reset succeed", ringbuf);
    return true;
}

/// @brief 销毁一个 ringbuf
/// @param [in] ringbuf  ringbuf 句柄指针
/// @retval true  成功
/// @retval false 失败
bool y_ringbuf_destroy(RINGBUF_st *ringbuf) {

    // 断言
    if (ringbuf == NULL) {
        YLOGD("ringbuf is NULL, no need to delete");
        return false;
    }

#    if Y_RINGBUF_USE_MUTEX_LOCK == 1
    // 销毁互斥锁
    if (_y_ringbuf_destroy_mutex_lock(ringbuf) == false) {
        YLOGE("ringbuf destroy mutex lock error, destroy ringbuf fail");
        return false;
    }
#    endif

    // 释放内存空间
    free(ringbuf->buf);
    free(ringbuf);

    YLOGI("ringbuf %p delete succeed", ringbuf);
    ringbuf = NULL;

    return true;
}

/// @brief 创建一个 ringbuf
/// @param [out] ringbuf ringbuf 句柄指针
/// @param [in]  length  ringbuf 长度 (max 65535)
/// @retval true  成功
/// @retval false 失败
bool y_ringbuf_create(RINGBUF_st **ringbuf, uint16_t length) {

    // 断言
    if (length == 0) {
        YLOGE("ringbuf->buf length cannot set 0, create ringbuf fail");
        return false;
    }
    if (ringbuf == NULL) {
        YLOGE("ringbuf is NULL, create ringbuf fail");
        return false;
    }

    // 初始化 ringbuf 句柄 相关参数
    RINGBUF_st *tmp_ringbuf = (RINGBUF_st *) malloc(sizeof(RINGBUF_st));  // 开辟 结构体句柄 所需要的空间
    if (tmp_ringbuf == NULL) {
        YLOGE("malloc RINGBUF_st error");
        return false;
    } else {
        memset(tmp_ringbuf, 0, sizeof(RINGBUF_st));  // 清零
    }

    tmp_ringbuf->buf = (uint8_t *) malloc(length);  // 开辟 ringbuf 所需要的空间
    if (tmp_ringbuf->buf == NULL) {
        YLOGE("malloc ringbuf->buf error");
        free(tmp_ringbuf);
        return false;
    } else {
        memset(tmp_ringbuf->buf, 0, length);  // 清零
    }

    tmp_ringbuf->length    = length;
    tmp_ringbuf->free_size = length;

#    if Y_RINGBUF_USE_MUTEX_LOCK == 1
    // 创建互斥锁
    if (_y_ringbuf_create_mutex_lock(tmp_ringbuf) == false) {
        free(tmp_ringbuf->buf);
        free(tmp_ringbuf);
        tmp_ringbuf = NULL;
        YLOGE("ringbuf create mutex lock error, create ringbuf fail");
        return false;
    }
#    endif

    // 获取初始化完成之后的指针
    *ringbuf = tmp_ringbuf;

    YLOGI("ringbuf %p create succeed", tmp_ringbuf);
    return true;
}



/// ------------------------------------------------------------------------------------------------------------------------------------
/// 条件编译结尾
/// ------------------------------------------------------------------------------------------------------------------------------------

#endif  // USE_Y_RINGBUF