/*
 * Copyright (C) 2018-2019 "IoT.bzh"
 * Author "Romain Forlot" <romain.forlot@iot.bzh>
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *	 http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#define _GNU_SOURCE
#include <fcntl.h>
#include <stdio.h>
#include <unistd.h>

#include "../utils/list.h"
#include "influxdb.h"
#include "tsdb.h"
#include "wrap-json.h"

CTLP_CAPI_REGISTER("influxdb");

CTLP_ONLOAD(plugin, ret)
{
    int err = 0;
    char* result;
    size_t result_size;
    CURL* request = curl_wrap_prepare_get(DEFAULT_DBHOST ":" DEFAULT_DBPORT "/ping", NULL, NULL);

    struct reader_args r_args = { NULL, NULL, 1000000 };
    plugin->context = (void*)&r_args;

    curl_wrap_perform(request, &result, &result_size);

    if (curl_wrap_response_code_get(request) != 204) {
        AFB_API_ERROR(plugin->api, "InfluxDB not reachable, please start it");
        err = ERROR;
    }

    curl_easy_cleanup(request);
    return err;
}

CTLP_CAPI(influxdb_ping, source, argsJ, eventJ)
{
    int ret = 0;
    char* result;
    size_t result_size;

    CURL* curl_req = curl_wrap_prepare_get(DEFAULT_DBHOST ":" DEFAULT_DBPORT "/ping", NULL, NULL);

    curl_wrap_perform(curl_req, &result, &result_size);

    if (curl_wrap_response_code_get(curl_req) != 204) {
        AFB_API_ERROR(source->api, "InfluxDB is offline.");
        ret = ERROR;
    } else {
        AFB_API_NOTICE(source->api, "InfluxDB is up and running.");
    }

    curl_easy_cleanup(curl_req);

    return ret;
}

size_t make_url(char* url, size_t l_url, const char* host, const char* port, const char* endpoint)
{
    bzero(url, l_url);

    /* Handle default host and port */
    host = host ? host : DEFAULT_DBHOST;
    port = port ? port : DEFAULT_DBPORT;

    strncat(url, host, strlen(host));
    strcat(url, ":");
    strncat(url, port, strlen(port));
    strcat(url, "/");
    strncat(url, endpoint, strlen(endpoint));
    strcat(url, "?db=" DEFAULT_DB);

    return strlen(url);
}

int create_database(afb_req_t request)
{
    int ret = 0;
    char* result;
    size_t result_size;

    // Declare query to be posted
    const char* post_data[2];
    post_data[0] = "q=CREATE DATABASE \"" DEFAULT_DB "\"";
    post_data[1] = NULL;

    CURL* curl_req = curl_wrap_prepare_post_unescaped(DEFAULT_DBHOST ":"  DEFAULT_DBPORT "/query", NULL, " ", post_data);
    curl_wrap_perform(curl_req, &result, &result_size);

    if (curl_wrap_response_code_get(request) != 200) {
        AFB_REQ_ERROR(request, "Can't create database.");
        ret = ERROR;
    }

    curl_easy_cleanup(curl_req);

    if (ret == 0)
        AFB_REQ_NOTICE(request, "Database '" DEFAULT_DB "' created");

    return ret;
}

void unpack_values(void* l, json_object* valuesJ, const char* key)
{
    add_elt((struct list**)l, key, "", valuesJ);
}

void unpack_metadata(void* l, json_object* valuesJ, const char* key)
{
    add_elt((struct list**)l, key, "", valuesJ);
}

void unpacking_from_api(void* s, json_object* valueJ, const char* key)
{
    size_t key_length = strlen(key);
    struct series_t* serie = (struct series_t*)s;

    /* Treat the 2 static key that could have been specified */
    if (strcasecmp("name", key) == 0)
        serie->name = json_object_get_string(valueJ);

    else if (strcasecmp("timestamp", key) == 0)
        serie->timestamp = (json_object_is_type(valueJ, json_type_int)) ? json_object_get_int64(valueJ) : 0;

    // metadata (AKA tags) are indexed into influxdb
    else if (strcasecmp("metadata", key) == 0)
        wrap_json_object_for_all(valueJ, unpack_metadata, (void*)&serie->serie_columns.tags);

    // value (AKA fields) are NOT indexed into influxdb
    else if (strcasecmp("value", key) == 0 || strcasecmp("values", key) == 0)
        wrap_json_object_for_all(valueJ, unpack_values, (void*)&serie->serie_columns.fields);

    /* Treat all key looking for tag and field object. Those ones could be find
       with the last 2 character. '_t' for tag and '_f' that are the keys that
       could be indefinite. Cf influxdb documentation:
       https://docs.influxdata.com/influxdb/v1.5/write_protocols/line_protocol_reference/ */
    else if (strncasecmp(&key[key_length - 2], "_t", 2) == 0)
        add_elt(&serie->serie_columns.tags, key, "", valueJ);

    else if (strncasecmp(&key[key_length - 2], "_f", 2) == 0)
        add_elt(&serie->serie_columns.fields, key, "", valueJ);
}

int unpack_metric_from_api(json_object* m, struct series_t* serie)
{
    wrap_json_object_for_all(m, unpacking_from_api, serie);

    if (!serie->timestamp) {
        serie->timestamp = get_ts();
    }

    return 0;
}