#include "drv_eth.h"
#include "lwip/opt.h"
#include "lwip/mem.h"
#include "lwip/memp.h"
#include "lwip/timeouts.h"
#include "netif/etharp.h"
#include "lwip/ethip6.h"
#include "osal.h"
#include "hal.h"
#include <string.h>

/* 硬件抽象层操作结构体 */
static const hal_ops_t *hal_ops = NULL;

static err_t low_level_output(struct netif *netif, struct pbuf *p)
{
    (void)netif;
    err_t errval;
    uint8_t *buffer = NULL;
    uint32_t len = p->tot_len;
    
    /* 分配缓冲区 */
    buffer = (uint8_t *)mem_malloc(len);
    if (buffer == NULL) {
        return ERR_MEM;
    }
    
    /* 复制数据到缓冲区 */
    pbuf_copy_partial(p, buffer, len, 0);
    
    /* 使用硬件抽象层发送数据 */
    if (hal_ops && hal_ops->eth && hal_ops->eth->send(buffer, len) == HAL_STATUS_OK) {
        errval = ERR_OK;
    } else {
        errval = ERR_IF;
    }
    
    /* 释放缓冲区 */
    mem_free(buffer);
    
    return errval;
}

static struct pbuf * low_level_input(struct netif *netif)
{
    (void)netif;
    struct pbuf *p = NULL;
    uint8_t *buffer = NULL;
    uint32_t rxLength = 0;
    
    /* 分配缓冲区 */
    buffer = (uint8_t *)mem_malloc(ETH_RX_BUF_SIZE);
    if (buffer == NULL) {
        return NULL;
    }
    
    /* 使用硬件抽象层接收数据 */
    if (hal_ops && hal_ops->eth && hal_ops->eth->recv(buffer, &rxLength, 100) == HAL_STATUS_OK)
    {
         if (rxLength > 0 && buffer != NULL) {
             /* 尝试使用 PBUF_REF 模式创建 pbuf，实现零拷贝 */
             p = pbuf_alloc(PBUF_RAW, rxLength, PBUF_POOL);
             if (p != NULL) {
                 pbuf_take(p, buffer, rxLength);
             } else {
                 osal_log_e("pbuf_alloc failed");
             }
         }
    } else {
        /* ReadData failed, maybe no data available */
    }
    
    /* 释放缓冲区 */
    mem_free(buffer);
    
    return p;
}

void ethernetif_input(struct netif *netif)
{
    struct pbuf *p;

    do {
        p = low_level_input(netif);
        if (p != NULL)
        {
            // osal_log_i("Rx: len=%d", p->tot_len); // Debug print
            if (netif->input(p, netif) != ERR_OK)
            {
                pbuf_free(p);
            }
        }
    } while(p != NULL);
}

err_t ethernetif_init(struct netif *netif)
{
    LWIP_ASSERT("netif != NULL", (netif != NULL));

#if LWIP_NETIF_HOSTNAME
    netif->hostname = "lwip";
#endif 

    netif->name[0] = 'e';
    netif->name[1] = 't';
    
    netif->output = etharp_output;
    netif->linkoutput = low_level_output;

    /* 获取硬件抽象层操作结构体 */
    hal_ops = hal_get_ops();
    if (hal_ops == NULL) {
        osal_log_e("Failed to get HAL ops");
        return ERR_IF;
    }

    /* 配置网络接口 */
    netif->hwaddr_len = 6;
    /* MAC地址由硬件抽象层初始化 */
    netif->mtu = 1500;
    netif->flags |= NETIF_FLAG_BROADCAST | NETIF_FLAG_ETHARP;
#if LWIP_IPV6
    netif->flags |= NETIF_FLAG_IGMP;
#endif

    return ERR_OK;
}

void ethernet_link_check_state(struct netif *netif)
{
    if (hal_ops && hal_ops->eth) {
        if (hal_ops->eth->get_link_status() == HAL_STATUS_OK) {
            if (!netif_is_link_up(netif)) {
                netif_set_link_up(netif);
                osal_log_i("Ethernet Link Up");
            }
        } else {
            if (netif_is_link_up(netif)) {
                netif_set_link_down(netif);
                osal_log_i("Ethernet Link Down");
            }
        }
    }
}