#include <stdlib.h>
#include <string.h>

#include "log.h"
#include "utils.h"
#include "kafka.h"
#include <MESA/MESA_prof_load.h>
#include <MESA/librdkafka/rdkafka.h>

#define MAX_SYMBOL_LEN 128

struct config
{
    int enable_debug;
    char brokerlist[MAX_SYMBOL_LEN];
    char sasl_username[MAX_SYMBOL_LEN];
    char sasl_passwd[MAX_SYMBOL_LEN];
    char topic_name[MAX_TOPIC_NUM][MAX_SYMBOL_LEN];
};

struct per_producer_per_topic
{
    rd_kafka_t *producer;
    rd_kafka_topic_t *topic;
};

struct kafka
{
    struct config cfg;
    struct per_producer_per_topic *pppt[MAX_TOPIC_NUM];
};

/******************************************************************************
 * Private API
 ******************************************************************************/

static void per_producer_per_topic_free(struct per_producer_per_topic *pppt)
{
    if (pppt)
    {
        if (pppt->topic)
        {
            rd_kafka_topic_destroy(pppt->topic);
            pppt->topic = NULL;
        }

        if (pppt->producer)
        {
            rd_kafka_destroy(pppt->producer);
            pppt->producer = NULL;
        }

        free(pppt);
        pppt = NULL;
    }
}

static struct per_producer_per_topic *per_producer_per_topic_new(const char *brokerlist, const char *sasl_username, const char *sasl_passwd, const char *topic_name)
{
    char err_str[1024] = {0};
    struct per_producer_per_topic *pppt = (struct per_producer_per_topic *)calloc(1, sizeof(struct per_producer_per_topic));
    if (!pppt)
    {
        return NULL;
    }

    rd_kafka_conf_t *conf = rd_kafka_conf_new();
    if (!conf)
    {
        LOG_ERROR("%s: failed to create kafka conf", LOG_TAG_KAFKA);
        goto error_out;
    }
    if (rd_kafka_conf_set(conf, "queue.buffering.max.messages", "1000000", err_str, sizeof(err_str)) != RD_KAFKA_CONF_OK)
    {
        LOG_ERROR("%s: failed to set kafka queue.buffering.max.messages, %s", LOG_TAG_KAFKA, err_str);
        goto error_out;
    }
    if (rd_kafka_conf_set(conf, "topic.metadata.refresh.interval.ms", "600000", err_str, sizeof(err_str)) != RD_KAFKA_CONF_OK)
    {
        LOG_ERROR("%s: failed to set kafka topic.metadata.refresh.interval.ms, %s", LOG_TAG_KAFKA, err_str);
        goto error_out;
    }
    if (rd_kafka_conf_set(conf, "client.id", topic_name, err_str, sizeof(err_str)) != RD_KAFKA_CONF_OK)
    {
        LOG_ERROR("%s: failed to set kafka client.id, %s", LOG_TAG_KAFKA, err_str);
        goto error_out;
    }

    // bootstrap.servers
    if (rd_kafka_conf_set(conf, "bootstrap.servers", brokerlist, err_str, sizeof(err_str)) != RD_KAFKA_CONF_OK)
    {
        LOG_ERROR("%s: failed to set kafka bootstrap.servers, %s", LOG_TAG_KAFKA, err_str);
        goto error_out;
    }

    if (strlen(sasl_username) > 0 && strlen(sasl_passwd) > 0)
    {
        if (rd_kafka_conf_set(conf, "security.protocol", "sasl_plaintext", err_str, sizeof(err_str)) != RD_KAFKA_CONF_OK)
        {
            LOG_ERROR("%s: failed to set kafka security.protocol, %s", LOG_TAG_KAFKA, err_str);
            goto error_out;
        }
        if (rd_kafka_conf_set(conf, "sasl.mechanisms", "PLAIN", err_str, sizeof(err_str)) != RD_KAFKA_CONF_OK)
        {
            LOG_ERROR("%s: failed to set kafka sasl.mechanisms, %s", LOG_TAG_KAFKA, err_str);
            goto error_out;
        }
        if (rd_kafka_conf_set(conf, "sasl.username", sasl_username, err_str, sizeof(err_str)) != RD_KAFKA_CONF_OK)
        {
            LOG_ERROR("%s: failed to set kafka sasl.username, %s", LOG_TAG_KAFKA, err_str);
            goto error_out;
        }
        if (rd_kafka_conf_set(conf, "sasl.password", sasl_passwd, err_str, sizeof(err_str)) != RD_KAFKA_CONF_OK)
        {
            LOG_ERROR("%s: failed to set kafka sasl.password, %s", LOG_TAG_KAFKA, err_str);
            goto error_out;
        }
    }
    else
    {
        if (rd_kafka_conf_set(conf, "security.protocol", "plaintext", err_str, sizeof(err_str)) != RD_KAFKA_CONF_OK)
        {
            LOG_ERROR("%s: failed to set kafka security.protocol, %s", LOG_TAG_KAFKA, err_str);
            goto error_out;
        }
    }

    // The conf object is freed by this function and must not be used or destroyed by the application sub-sequently.
    pppt->producer = rd_kafka_new(RD_KAFKA_PRODUCER, conf, err_str, sizeof(err_str));
    conf = NULL;
    if (pppt->producer == NULL)
    {
        LOG_ERROR("%s: failed to create kafka producer, %s", LOG_TAG_KAFKA, err_str);
        goto error_out;
    }

    pppt->topic = rd_kafka_topic_new(pppt->producer, topic_name, NULL);
    if (pppt->topic == NULL)
    {
        LOG_ERROR("%s: failed to create kafka topic: %s", LOG_TAG_KAFKA, topic_name);
        goto error_out;
    }

    return pppt;

error_out:
    if (conf)
    {
        rd_kafka_conf_destroy(conf);
    }

    per_producer_per_topic_free(pppt);
    return NULL;
}

/******************************************************************************
 * Public API -- Kafka
 ******************************************************************************/

// due to limit by client.id, need per producer per topic
struct kafka *kafka_create(const char *profile)
{
    struct kafka *handle = (struct kafka *)calloc(1, sizeof(struct kafka));
    if (!handle)
    {
        return NULL;
    }

    MESA_load_profile_int_def(profile, "kafka", "enable_debug", &handle->cfg.enable_debug, 0);
    MESA_load_profile_string_def(profile, "kafka", "brokerlist", handle->cfg.brokerlist, sizeof(handle->cfg.brokerlist), "");
    MESA_load_profile_string_def(profile, "kafka", "sasl_username", handle->cfg.sasl_username, sizeof(handle->cfg.sasl_username), "");
    MESA_load_profile_string_def(profile, "kafka", "sasl_passwd", handle->cfg.sasl_passwd, sizeof(handle->cfg.sasl_passwd), "");
    MESA_load_profile_string_def(profile, "kafka", "topic_name", handle->cfg.topic_name[TOPIC_RULE_HITS], sizeof(handle->cfg.topic_name[TOPIC_RULE_HITS]), "");

    if (strlen(handle->cfg.brokerlist) == 0)
    {
        LOG_ERROR("%s: brokerlist is empty", LOG_TAG_KAFKA);
        goto error_out;
    }

    for (int i = 0; i < MAX_TOPIC_NUM; i++)
    {
        if (strlen(handle->cfg.topic_name[i]) == 0)
        {
            LOG_ERROR("%s: topic_name[%d] is empty", LOG_TAG_KAFKA, i);
            goto error_out;
        }
    }

    for (int i = 0; i < MAX_TOPIC_NUM; i++)
    {
        handle->pppt[i] = per_producer_per_topic_new(handle->cfg.brokerlist, handle->cfg.sasl_username, handle->cfg.sasl_passwd, handle->cfg.topic_name[i]);
        if (!handle->pppt[i])
        {
            goto error_out;
        }
    }

    return handle;

error_out:
    kafka_destroy(handle);
    return NULL;
}

void kafka_destroy(struct kafka *handle)
{
    if (handle)
    {
        for (int i = 0; i < MAX_TOPIC_NUM; i++)
        {
            per_producer_per_topic_free(handle->pppt[i]);
            handle->pppt[i] = NULL;
        }

        free(handle);
        handle = NULL;
    }
}

int kafka_send(struct kafka *handle, enum topic_idx idx, const char *data, int len)
{
    if (!handle)
    {
        LOG_ERROR("%s: handle is NULL", LOG_TAG_KAFKA);
        return -1;
    }

    if (idx < 0 || idx >= MAX_TOPIC_NUM)
    {
        LOG_ERROR("%s: invalid topic index: %d", LOG_TAG_KAFKA, idx);
        return -1;
    }

    if (handle->pppt[idx])
    {
        if (rd_kafka_produce(handle->pppt[idx]->topic, RD_KAFKA_PARTITION_UA, RD_KAFKA_MSG_F_COPY, (void *)data, len, NULL, 0, NULL) == -1)
        {
            LOG_ERROR("%s: failed to produce message with topic [%d], %s", LOG_TAG_KAFKA, idx, rd_kafka_err2str(rd_kafka_last_error()));
            return -1;
        }
        else
        {
            if (handle->cfg.enable_debug)
            {
                LOG_DEBUG("%s: success to produce message with topic [%d], %s", LOG_TAG_KAFKA, idx, data);
            }
            return 0;
        }
    }
    else
    {
        LOG_ERROR("%s: topic %d not initialized", LOG_TAG_KAFKA, idx);
        return -1;
    }
}