#include <c_PtrLinkBag.h>



/* ------------------------------------------------------------------------------------------------------------------ */
/*  */

// 原地初始化：绑定分配器并建立哑哨兵头节点
c_err_t c_PtrLinkBag_Init(c_PtrLinkBag_t* self, c_Allocator_t* allocator) {
    if (!self) return C_ERR_PARAM;

    // 内置绑定：如果传入 NULL，无缝降级为系统默认分配器
    self->allocator = (allocator != NULL) ? *allocator : c_DefaultAllocator;
    self->size = 0;
    self->head = 0;
    return C_ERR_OK;
}

// 快速头插法 (真正的 O(1) 尾部或头部无抖动挂载)
c_PtrLinkNode_t* c_PtrLinkBag_Add(c_PtrLinkBag_t* self, void* ptr) {
    if (!self || !ptr) return NULL;

    // 内部闭环调用自身的内置管理器
    c_PtrLinkNode_t* new_node = (c_PtrLinkNode_t*)c_Allocator_Alloc(&self->allocator, sizeof(c_PtrLinkNode_t));
    if (!new_node) return NULL;

    new_node->ptr = ptr;
    new_node->next = self->head;
    self->head = new_node;

    self->size++;
    return new_node;
}

// 基于二级指针的自主安全裁剪 (O(N) 线性过滤)
c_err_t c_PtrLinkBag_Remove(c_PtrLinkBag_t* self, void* ptr) {
    if (!self || !self->head || !ptr) return C_ERR_PARAM;

    // 二级指针指向 Dummy Head 的下一个节点指针坑位物理地址
    c_PtrLinkNode_t** pp = &(self->head->next);

    while (*pp != NULL) {
        c_PtrLinkNode_t* entry = *pp;
        if (entry->ptr == ptr) {
            // 精妙裁剪：前驱节点的 next 直接指去被删节点的下一跳
            *pp = entry->next;

            // 内部自主物理销毁，账实同步
            c_Allocator_Free(&self->allocator, entry);
            self->size--;
            return C_ERR_OK;
        }
        pp = &(entry->next);
    }
    return C_ERR_NOTFOUND;
}


// 彻底解体
void c_PtrLinkBag_Destroy(c_PtrLinkBag_t* self) {
    if (!self) return;

    while (self->head != NULL) {
        c_PtrLinkNode_t* entry = self->head;
        self->head = entry->next;
        c_Allocator_Free(&self->allocator, entry);
    }
}