#include "mqtt_config.h"

#include "wifi/wifi_connect.h"
#include "mbedtls/md.h"

#include <string.h>
#include <stdio.h>


static mqtt_config_t mqtt_config;


/*
 * 生成紧凑MAC == 用户名
 *
 * AA:BB:CC:DD:EE:FF -> AABBCCDDEEFF(大写)
 */
static int make_compact_mac(char *buf, uint32_t len)
{
    uint8_t mac[6];
    int i;

    if (!buf || len < 13)
    {
        return -1;
    }

    if (wifi_get_mac(mac))
    {
        return -1;
    }

    for (i = 0; i < 6; i++)
    {
        sprintf(buf + i * 2, "%02X", mac[i]);
    }

    return 0;
}


/*
 * 生成密码
 *
 * password = MD5(PRODUCT_SECRET + client_id) 小写hex
 */
static int make_password(const char *client_id, char *buf, uint32_t len)
{
    char raw[128];
    unsigned char digest[16];
    const mbedtls_md_info_t *md_info;
    int i;

    if (!client_id || !buf || len < 33)
    {
        return -1;
    }

    snprintf(raw, sizeof(raw), "%s%s", MQTT_PRODUCT_SECRET, client_id);

    md_info = mbedtls_md_info_from_type(MBEDTLS_MD_MD5);
    if (!md_info ||
        mbedtls_md(md_info, (const unsigned char *)raw, strlen(raw), digest))
    {
        return -1;
    }

    for (i = 0; i < 16; i++)
    {
        sprintf(buf + i * 2, "%02x", digest[i]);
    }
    buf[32] = '\0';

    return 0;
}


void mqtt_config_init(void)
{
    char device_name[13];

    memset(
        &mqtt_config,
        0,
        sizeof(mqtt_config)
    );


    /*
     * MQTT服务器
     */
    strcpy(
        mqtt_config.host,
        MQTT_SERVER_HOST
    );

    mqtt_config.port = MQTT_SERVER_PORT;


    mqtt_config.keepalive = 60;//秒


    /*
     * 设备身份
     * username = 紧凑MAC
     * client_id = PRODUCT_KEY_MAC_MODEL
     * password  = MD5(PRODUCT_SECRET + client_id)
     * 
     */
    if (make_compact_mac(device_name, sizeof(device_name))) {
        strcpy(device_name, "unknown");
    }

    strcpy(
        mqtt_config.username,
        device_name
    );

    snprintf(
        mqtt_config.client_id,
        sizeof(mqtt_config.client_id),
        "%s_%s_%s",
        MQTT_PRODUCT_ID,
        device_name,
        MQTT_DEVICE_MODEL
    );

    make_password(
        mqtt_config.client_id,
        mqtt_config.password,
        sizeof(mqtt_config.password)
    );


    /*
     * topic
     */
    snprintf(
        mqtt_config.subscribe_topic,
        sizeof(mqtt_config.subscribe_topic),
        "/sys/%s/%s/c/#",
        MQTT_PRODUCT_ID,
        device_name
    );

    snprintf(
        mqtt_config.publish_topic,
        sizeof(mqtt_config.publish_topic),
        "/sys/%s/%s/s/event/property/post",
        MQTT_PRODUCT_ID,
        device_name
    );


}

mqtt_config_t *mqtt_config_get(void)
{

    return &mqtt_config;

}