/*
 * Copyright (C) 2015 by Multi-Tech Systems
 *
 * This file is part of lora-query.
 *
 * lora-query is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 2 of the License, or
 * (at your option) any later version.
 *
 * lora-query is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with lora-query.  If not, see <http://www.gnu.org/licenses/>.
 *
 */
#include <mts/MTS_Text.h>
#include <mts/MTS_Logger.h>
#include <json/json.h>
#include <getopt.h>
#include <sys/stat.h>
#include <arpa/inet.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <errno.h>
#include <string.h>
#include <stdlib.h>
#include <stdio.h>
#include <sstream>
#include <iostream>
#include <fstream>
#include <algorithm>
#include "Version.h"

#define INET_ADDR "127.0.0.1"
#define INET_PORT 6677
#define MAX_RECEIVED_BYTES 2000
#define TIMEOUT 100 /* By default 100 msec */

int opt_get_stats    = 0;
int opt_get_nodelist = 0;
int opt_get_json = 0;
int opt_stats_reset = 0;
int timeout  = TIMEOUT;
const char* cmd_stats    = "stats";
const char* cmd_stats_reset = "stats reset";
const char* cmd_nodelist = "node list";
const std::string lora_network_stats_json("/var/tmp/lora_network_stats.json");
const std::string lora_network_nodelist("/var/tmp/lora_network_nodelist");
const std::string lora_network_nodelist_json("/var/tmp/lora_network_nodelist.json");
std::stringstream receiveStream;

const int nodeSize = 15;
const std::string NODE_ADDR("nodeAddr");
const std::string NODE_DEV_EUI("devEui");
const std::string NODE_JOINED("joined");
const std::string NODE_SEQ_NUM("seqNum");
const std::string NODE_PKTS_UP("pktsUp");
const std::string NODE_PKTS_DOWN("pktsDown");
const std::string NODE_PKTS_1ST("pkts1st");
const std::string NODE_PKTS_2ND("pkts2nd");
const std::string NODE_DROPPED("dropped");
const std::string NODE_RSSI_MIN("rssiMin");
const std::string NODE_RSSI_MAX("rssiMax");
const std::string NODE_RSSI_AVR("rssiAvg");
const std::string NODE_SNR_MIX("snrMin");
const std::string NODE_SNR_MAX("snrMax");
const std::string NODE_SNR_AVR("snrAvg");

void getloraData(const char *command);
void printStats(void);
void printNodeList(void);
void saveToFile(const std::string& fileName, const std::string& buffer);
void parseOptions(int argc, char** argv);
void printHelp(const std::string& sApp);
std::string trim(std::string& str);

int main(int argc, char**argv)
{
    parseOptions(argc, argv);

    if (opt_stats_reset) {
        getloraData(cmd_stats_reset);
    }

    if (opt_get_stats) {
        getloraData(cmd_stats);
        printStats();
    }
    if (opt_get_nodelist) {
        getloraData(cmd_nodelist);
        if (opt_get_json) {
            printNodeList();
        } else {
            if (receiveStream.str().empty() ) {
                return 0;
            }
            saveToFile(lora_network_nodelist, receiveStream.str());
            std::cout << receiveStream.str();
        }
    }
    return 0;
}

void getloraData(const char *command) {
    int sockfd;
    struct sockaddr_in servaddr;
    int receiveBytes = 0;
    char receiveMessage[MAX_RECEIVED_BYTES];
    struct timeval tv;

    tv.tv_sec = timeout / 1000;
    tv.tv_usec = (timeout % 1000) * 1000;

    receiveStream.str("");
    receiveStream.clear();

    if (NULL == command) {
       printError("Command is null\n");
       return;
    }

    sockfd=socket(AF_INET,SOCK_DGRAM,0);
    bzero(&servaddr,sizeof(servaddr));
    servaddr.sin_family = AF_INET;
    servaddr.sin_addr.s_addr=inet_addr(INET_ADDR);
    servaddr.sin_port=htons(INET_PORT);
    memset(receiveMessage, 0, MAX_RECEIVED_BYTES);

    if (setsockopt(sockfd, SOL_SOCKET, SO_RCVTIMEO, &tv, sizeof(tv)) < 0) {
        printError("setsockopt error\n");
        return;
    }

    sendto(sockfd, command, strlen(command), 0, (struct sockaddr *)&servaddr, sizeof(servaddr));

    while(1) {
        receiveBytes = recvfrom(sockfd, receiveMessage, MAX_RECEIVED_BYTES, 0, NULL, NULL);
        if(receiveBytes < 0) {
           /*printf("timeout\n");*/
           break;
        }
        receiveStream << std::string(receiveMessage, receiveBytes);
    }
}

void printStats() {
    Json::Reader reader;
    Json::Value stats;

    if (receiveStream.str().empty() ) {
        return;
    }

    if (!reader.parse(receiveStream.str(), stats), false) {
        printError("Error parsing JSON: [%s]", receiveStream.str().c_str());
    }

    // Replace underscores keys with camel-case.
    if (stats.isObject()) {
        Json::Value::Members keys = stats.getMemberNames();
        std::string newKey;
        for (Json::Value::Members::iterator it = keys.begin(); it != keys.end(); ++it) {
            const std::string& key = *it;
            newKey.clear();
            for (size_t i = 0; i < key.length() ; ++i) {
                if (('_' == key[i]) || ('-' == key[i])) {
                    if ((i + 1) < key.length()) {
                        newKey.push_back(std::toupper(key[++i]));
                    }
                } else {
                    newKey.push_back(key[i]);
                }
            }
            stats[newKey] = stats[key];
            stats.removeMember(key);
        }
    }
    saveToFile(lora_network_stats_json, stats.toStyledString());
    std::cout << stats.toStyledString();
}

void printNodeList() {
    std::string line;
    std::vector<std::string> parts;
    Json::Value nodeList = Json::ValueType::arrayValue;

    if (receiveStream.str().empty() ) {
        return;
    }

    getline(receiveStream, line);
    while (1) {
        getline(receiveStream, line);
        if (line.size() == 0)
            break;

        line = trim(line);
        parts = MTS::Text::split(line, " ");

        if (nodeSize == parts.size()) {
            Json::Value jNode(Json::objectValue);
            jNode[NODE_ADDR]      = parts[0];
            jNode[NODE_DEV_EUI]   = parts[1];
            jNode[NODE_JOINED]    = parts[2];
            jNode[NODE_SEQ_NUM]   = atoi(parts[3].c_str());
            jNode[NODE_PKTS_UP]   = atoi(parts[4].c_str());
            jNode[NODE_PKTS_DOWN] = atoi(parts[5].c_str());
            jNode[NODE_PKTS_1ST]  = atoi(parts[6].c_str());
            jNode[NODE_PKTS_2ND]  = atoi(parts[7].c_str());
            jNode[NODE_DROPPED]   = atoi(parts[8].c_str());
            jNode[NODE_RSSI_MIN]  = atoi(parts[9].c_str());
            jNode[NODE_RSSI_MAX]  = atoi(parts[10].c_str());
            jNode[NODE_RSSI_AVR]  = atoi(parts[11].c_str());
            jNode[NODE_SNR_MIX]   = atoi(parts[12].c_str());
            jNode[NODE_SNR_MAX]   = atoi(parts[13].c_str());
            jNode[NODE_SNR_AVR]   = atoi(parts[14].c_str());

            nodeList.append(jNode);
        }
        else {
            printError("Incorrect Node Data!  parts.size() = [%d]\n",  parts.size());
        }
    }
    saveToFile(lora_network_nodelist_json, nodeList.toStyledString());
    std::cout << nodeList.toStyledString();
}

void saveToFile(const std::string& fileName, const std::string& buffer) {
    std::ofstream outFile;
    outFile.open(fileName);
    outFile << buffer;
    outFile.close();
}

void parseOptions(int argc, char** argv) {

    if(argc == 1) {
        printHelp(argv[0]);
        exit(0);
    }

    const char* short_options = "hvsirnjt:";

    const struct option long_options[] = {
        {"help",      no_argument,       0, 'h'},
        {"version",   no_argument,       0, 'v'},
        {"stats",     no_argument,       0, 's'},
        {"stats-reset", no_argument,     0, 'r'},
        {"node-list", no_argument,       0, 'n'},
        {"json",      no_argument,       0, 'j'},
        {"timeout",   required_argument, 0, 't'},
        {0, 0, 0, 0}
    };

    int rez;
    int option_index;

    while ((rez=getopt_long(argc, argv, short_options, long_options, &option_index))!=-1) {
        switch(rez){
            case 's': {
                ++opt_get_stats;
                break;
            };
            case 'r': {
               ++opt_stats_reset;
               break;
            };
            case 'n': {
                ++opt_get_nodelist;
                break;
            };
            case 'j': {
                ++opt_get_json;
                break;
            };
            case 't': {
                timeout = atoi(optarg);
                break;
            }
            case 'v':
                printf("Version: %s\n", Version::version.c_str());
                exit(0);
                break;
            case 'h': 
            case '?':
            default: {
                printHelp(argv[0]);
                exit(0);
                break;
            };
        };
    };
}

void printHelp(const std::string& sApp) {
    printf("Usage: %s [-t timeout] [-s] [-n]\n", sApp.c_str());
    printf("\tSimple UDP client utility to pull info from LoRa Network server\n");
    printf("\t--timeout (t)     : UDP recv timeout, default: 100 (msecs)\n");
    printf("\t--stats (s)       : get LoRa Network server statistics\n");
    printf("\t--stats-reset (r) : reset LoRa Network server statistics\n");
    printf("\t--node-list (n)   : get Node List\n");
    printf("\t--json (j)        : data in json format\n");
    printf("\t--help (?)        : returns this message\n");
    printf("\t--version (v)     : print version\n");
}

std::string trim(std::string& str) {
    str.erase(std::unique(str.begin(), str.end(), [](char a, char b) { return a == ' ' && b == ' '; } ), str.end() );
    return str;
}