//
// Created by xajhuang on 2023/3/23.
//

#include <time.h>
#include "lease.h"
#include "user_errno.h"
#include "zlog_module.h"
#include "database.h"
#include "user_mgr.h"
#include "rfc2131.h"
#include "dhcp_network.h"
#include "db_interface.h"

#define PREALLOC_IP_TIMEOUT (60)

typedef struct {
    U32            ipAddr;
    U8             macAddr[ETH_ALEN];
    U32            bitset;
    PIPPOOL_INFO   pCtx;
    U32            timeStamp;
    UT_hash_handle hh;
} PRE_ALLOC_IP, *PPRE_ALLOC_IP;

//static PMAC_FILTER   g_allowTbl     = NULL;
//static PMAC_FILTER   g_blackListTbl = NULL;
//static PPRE_ALLOC_IP g_pPreAllocIp = NULL;

U32 lease_is_pre_assign(PDHCP_REQ pReq) {
    char macStr[20] = {0};
    U32  ipAddr;

    MAC_TO_STR(pReq->cliMac, macStr);
    if (lease_get_pre_assign(pReq->uid, macStr, pReq->hostName, &ipAddr) == ERR_ITEM_EXISTS) {
        return ipAddr;
    }

    return 0;
}

//int pre_alloc_dhcp_res(U32 uid, const char *pMac, U32 *pOutIp, PIPPOOL_INFO *pOutPool) {
int pre_alloc_dhcp_res(PDHCP_REQ pReq, U32 *pOutIp, PIPPOOL_INFO *pOutPool) {
    PIPPOOL_INFO  pPool, pTemp;
    PPRE_ALLOC_IP pNewIp, pTmp, pCache = NULL;
    PIPPOOL_INFO  pUserPool;

    if (pReq == NULL || pOutIp == NULL || pOutPool == NULL) {
        LOG_MOD(error, ZLOG_MOD_DHCPD, "Input params error: %p, %p\n", pOutIp, pOutPool);
        return -ERR_INPUT_PARAMS;
    }

    pUserPool = user_get_pool(pReq->uid);
    if (pUserPool == NULL) {
        LOG_MOD(error, ZLOG_MOD_DHCPD, "Can't found avaliable address pool\n");
        return -ERR_DHCP_NO_POOL;
    }

    // 遍历当前用户所有IP地址池
    HASH_ITER(hh, pUserPool, pPool, pTemp) {
        U32 addr;

        // 查看是否预分配过该设备
        if ((addr = lease_is_pre_assign(pReq)) != 0) {
            *pOutIp   = addr;
            *pOutPool = pPool;
            return ERR_SUCCESS;
        }

        while ((addr = bitset_minimum(pPool->assignPool)) > 0) {
            U32 ipAddr = (pPool->minAddr & pPool->netMask) + addr;

            // 查找租约配置文件中是否记录了曾经分配的地址, 如果已经分配则获取下一个
            // TODO: add process
            //            if (FALSE) {
            //                bitset_set(pPool->assignPool, addr);
            //                continue;
            //            }

            // 查找IP地址是否已经被预分配, 未分配直接分配IP地址
            if (lease_ip_is_pre_assign(pReq->uid, ipAddr) == FALSE) {
                lease_db_add_pre_assign(pReq, ipAddr, pPool);

                *pOutIp   = ipAddr;
                *pOutPool = pPool;

                bitset_cls_bit(pPool->assignPool, addr);

                LOG_MOD(trace, ZLOG_MOD_DHCPD, "Select ipaddr %08X at %d of %p\n", ipAddr, addr, pPool->assignPool);
                return ERR_SUCCESS;
            }
        }
    }

    // 清理所有超时的预分配IP
    lease_clearup_timeout_pre_assign();
    // 没有可预分配的IP，报错
    LOG_MOD(error,
            ZLOG_MOD_DHCPD,
            "No free ipaddress in poll:  uid = %u, pool = 0x%08X\n",
            pReq->uid,
            pUserPool->poolKey);
    return -ERR_DHCP_NO_ADDR;
}

int dhcp_lease_init() {
    int rc = 0;

    rc = lease_init_database();

    if (rc != ERR_SUCCESS) {
        return rc;
    }

    return ERR_SUCCESS;
}