/**
 * Copyright (c) Huawei Technologies Co., Ltd. 2023. All rights reserved.
 * 内部基础模块，所有参数合法性由调用者保证
 */
#ifndef BINARY_SEARCH_C_
#define BINARY_SEARCH_C_
#include "c_base.h"

#ifdef __cplusplus
extern "C" {
#endif

typedef void *(*FnBinaryGet)(void *appInfo, size_t id);
typedef int (*FnBinaryCompare)(void *a, void *b, void *appInfo);

static inline int BinarySearchClosest(
    void *appInfo, size_t size, void *key, FnBinaryGet fnBinaryGet, FnBinaryCompare fnComp, size_t *closestIndex)
{
    if (size == 0) {
        *closestIndex = 0;
        return -1;
    }

    size_t left = 0;
    size_t right = size - 1;
    size_t mid;
    int compRet = 0;
    while (left <= right) {
        mid = (left + right) >> 1;
        void *midData = fnBinaryGet(appInfo, mid);
        compRet = fnComp(key, midData, appInfo);
        if (compRet > 0) {
            left = mid + 1;
        } else if (compRet < 0) {
            if (mid == 0) {
                break;
            }
            right = mid - 1;
        } else {
            *closestIndex = mid;
            return 0;
        }
    }
    *closestIndex = mid;
    return compRet;
};

#ifdef __cplusplus
}
#endif
#endif