#include <stdio.h>
#include <limits.h>
#include <stdlib.h>
#include <unistd.h>
#include "fileutil.h"
#include "strutil.h"
#include "mqttcfg.h"
#include "debug.h"

#define _DEFAULT_CFG_FILE_NAME					"mqttcl.cfg.json"

#define _CFG_KEY_NAME_BROKER_ADDR				"brokerAddr"
#define _CFG_KEY_NAME_BROKER_PORT				"brokerPort"
#define _CFG_KEY_NAME_DEFAULT_QOS				"defaultQos"
#define _CFG_KEY_NAME_DEFAULT_RETAIN			"defaultRetain"
#define _CFG_KEY_NAME_DEVICE_PREFIX				"devicePrefix"
#define _CFG_KEY_NAME_DEVICE_ID					"deviceID"
#define _CFG_KEY_NAME_TLS_MODE					"tlsMode"
#define _CFG_KEY_NAME_TLS_CA_CRT_FILE			"tlsCaCrtFile"
#define _CFG_KEY_NAME_TLS_CL_CRT_FILE			"tlsClCrtFile"
#define _CFG_KEY_NAME_TLS_CL_KEY_FILE			"tlsClKeyFile"
#define _CFG_KEY_NAME_TLS_PSK					"tlsPsk"

/////////////////////////////////////////////////////////////////////////////

CMqttClConfig::CMqttClConfig(const char *pszShmUuid) : m_strShmID(formatString("SHM-%s", strucase(pszShmUuid).c_str())), m_nBrokerPort(0), m_nDefaultQOS(0), m_bDefaultRetain(false), m_nTlsMode(0)
{
}

CMqttClConfig::~CMqttClConfig(void)
{
}

/////////////////////////////////////////////////////////////////////////////
// LoadCfg

bool CMqttClConfig::LoadCfg(const char *pszCfgFilePath, CLogfile &rlf)
{
	char szCfgFilePath[PATH_MAX];
	std::string strErr;

	if(!pszCfgFilePath)
	{	// use default config file path
		pszCfgFilePath = ::BuildCanonicalFilePath(NULL, _DEFAULT_CFG_FILE_NAME, szCfgFilePath, sizeof(szCfgFilePath));
	}

	/////////////////////////////////////////////////////////////////////////
	// load and parse config file

	json_t *pjtCfg;
	json_error_t err;

	if(!(pjtCfg = ::json_load_file(pszCfgFilePath, JSON_REJECT_DUPLICATES, &err)))
	{
		rlf.Error("CMqttClConfig::LoadCfg: %s!\n", err.text);
		return false;
	}

	CJson_t jtCfg(pjtCfg, true);

	/////////////////////////////////////////////////////////////////////////
	// tlsMode

	if(!GetIntValue(jtCfg, _CFG_KEY_NAME_TLS_MODE, m_nTlsMode, strErr))
	{
		m_nTlsMode = MQTTCL_TLS_MODE_OFF;
		rlf.Warning("CMqttClConfig::LoadCfg: %s! TLS will not be used!\n", strErr.c_str());
	}
	else if(m_nTlsMode < MQTTCL_TLS_MODE_OFF)
	{
		rlf.Warning("CMqttClConfig::LoadCfg: Invalid TLS mode: %d! TLS will be disabled!\n", m_nTlsMode);
		m_nTlsMode = MQTTCL_TLS_MODE_OFF;
	}
	else if(m_nTlsMode > MQTTCL_TLS_MODE_PSK)
	{
		rlf.Warning("CMqttClConfig::LoadCfg: Invalid TLS mode: %d! TLS mode will be set to PSK!\n", m_nTlsMode);
		m_nTlsMode = MQTTCL_TLS_MODE_PSK;
	}

	/////////////////////////////////////////////////////////////////////////
	// brokerAddr

	if(!GetStringValue(jtCfg, _CFG_KEY_NAME_BROKER_ADDR, m_strBrokerAddr, strErr))
	{
		rlf.Error("CMqttClConfig::LoadCfg: %s!\n", strErr.c_str());
		return false;
	}

	/////////////////////////////////////////////////////////////////////////
	// brokerPort

	if(!GetIntValue(jtCfg, _CFG_KEY_NAME_BROKER_PORT, m_nBrokerPort, strErr))
	{
		m_nBrokerPort = (m_nTlsMode > MQTTCL_TLS_MODE_OFF) ? 8883 : 1883;
		rlf.Warning("CMqttClConfig::LoadCfg: %s! Using default broker port %d!\n", strErr.c_str(), m_nBrokerPort);
	}
	else if(m_nBrokerPort < 0 || m_nBrokerPort > 0xffff)
	{
		rlf.Error("CMqttClConfig::LoadCfg: Invalid broker port number: %d!\n", m_nBrokerPort);
		return false;
	}

	/////////////////////////////////////////////////////////////////////////
	// defaultQos

	if(!GetIntValue(jtCfg, _CFG_KEY_NAME_DEFAULT_QOS, m_nDefaultQOS, strErr))
	{
		m_nDefaultQOS = MQTTCL_DEFAULT_QOS;
		rlf.Warning("CMqttClConfig::LoadCfg: %s! Using default QOS: %d!\n", strErr.c_str(), m_nDefaultQOS);
	}
	else if(m_nDefaultQOS < MQTTCL_MIN_QOS)
	{
		rlf.Warning("CMqttClConfig::LoadCfg: Invalid QOS: %d - using %d!\n", m_nDefaultQOS, MQTTCL_MIN_QOS);
		m_nDefaultQOS = MQTTCL_MIN_QOS;
	}
	else if(m_nDefaultQOS > MQTTCL_MAX_QOS)
	{
		rlf.Warning("CMqttClConfig::LoadCfg: Invalid QOS: %d - using %d!\n", m_nDefaultQOS, MQTTCL_MAX_QOS);
		m_nDefaultQOS = MQTTCL_MAX_QOS;
	}

	/////////////////////////////////////////////////////////////////////////
	// defaultRetain

	if(!GetBoolValue(jtCfg, _CFG_KEY_NAME_DEFAULT_RETAIN, m_bDefaultRetain, strErr))
	{
		m_bDefaultRetain = MQTTCL_DEFAULT_RETAIN;
		rlf.Warning("CMqttClConfig::LoadCfg: %s! Using default retain \"%s\"!\n", strErr.c_str(), m_bDefaultRetain ? "true" : "false");
	}

	/////////////////////////////////////////////////////////////////////////
	// devicePrefix

	if(!GetStringValue(jtCfg, _CFG_KEY_NAME_DEVICE_PREFIX, m_strDevicePrefix, strErr))
	{
		m_strDevicePrefix = MQTTCL_DEVICE_PREFIX;
		rlf.Warning("CMqttClConfig::LoadCfg: %s! Using default device prefix \"%s\"!\n", strErr.c_str(), m_strDevicePrefix.c_str());
	}

	/////////////////////////////////////////////////////////////////////////
	// deviceID

	if(GetStringValue(jtCfg, _CFG_KEY_NAME_DEVICE_ID, m_strDeviceID, strErr))
	{
		rlf.Info("CMqttClConfig::LoadCfg: Using configured device ID: \"%s\"!\n", m_strDeviceID.c_str());
	}
	else
	{
		m_strDeviceID = CreateDeviceID(m_strDevicePrefix.c_str());
	}

	/////////////////////////////////////////////////////////////////////////
	// m_nTlsMode == (MQTTCL_TLS_MODE_CRT || MQTTCL_TLS_MODE_PSK)

	if(m_nTlsMode == MQTTCL_TLS_MODE_CRT)
	{
		/////////////////////////////////////////////////////////////////////
		// tlsCaCrtFile

		if(!GetStringValue(jtCfg, _CFG_KEY_NAME_TLS_CA_CRT_FILE, m_strTlsCaCrtFile, strErr))
		{
			rlf.Error("CMqttClConfig::LoadCfg: %s!\n", strErr.c_str());
			return false;
		}

		/////////////////////////////////////////////////////////////////////
		// tlsClCrtFile

		if(!GetStringValue(jtCfg, _CFG_KEY_NAME_TLS_CL_CRT_FILE, m_strTlsClCrtFile, strErr))
		{
			rlf.Error("CMqttClConfig::LoadCfg: %s!\n", strErr.c_str());
			return false;
		}

		/////////////////////////////////////////////////////////////////////
		// tlsClKeyFile

		if(!GetStringValue(jtCfg, _CFG_KEY_NAME_TLS_CL_KEY_FILE, m_strTlsClKeyFile, strErr))
		{
			rlf.Error("CMqttClConfig::LoadCfg: %s!\n", strErr.c_str());
			return false;
		}
	}
	else if(m_nTlsMode == MQTTCL_TLS_MODE_PSK)
	{
		/////////////////////////////////////////////////////////////////////
		// tlsPsk

		if(!GetStringValue(jtCfg, _CFG_KEY_NAME_TLS_PSK, m_strTlsPSK, strErr))
		{
			rlf.Error("CMqttClConfig::LoadCfg: %s!\n", strErr.c_str());
			return false;
		}
	}

	return true;
}

/////////////////////////////////////////////////////////////////////////////

bool CMqttClConfig::GetValue(CJson_t &rjtParent, const char *pszKey, CJson_t &rjtVal, std::string &strErr)
{
	if(!rjtParent.GetValue(pszKey, rjtVal))
	{
		strErr = formatString("Key \"%s\" not found", pszKey);
		return false;
	}
	return true;
}

/////////////////////////////////////////////////////////////////////////////

bool CMqttClConfig::GetBoolValue(CJson_t &rjtParent, const char *pszKey, bool &rbVal, std::string &strErr)
{
	CJson_t jtVal;

	if(GetValue(rjtParent, pszKey, jtVal, strErr))
	{
		int nType;

		switch((nType = jtVal.Type()))
		{
		case JSON_TRUE:
		case JSON_FALSE:
			rbVal = (nType == JSON_TRUE);
			return true;
		default:
			strErr = formatString("\"%s\" (type=%d) is not a boolean value", pszKey, nType);
			return false;
		}
	}

	return false;
}

/////////////////////////////////////////////////////////////////////////////

bool CMqttClConfig::GetIntValue(CJson_t &rjtParent, const char *pszKey, int &rnVal, std::string &strErr)
{
	CJson_t jtVal;

	if(GetValue(rjtParent, pszKey, jtVal, strErr))
	{
		if(json_is_integer(jtVal.operator const json_t*()))
		{
			rnVal = (int)::json_integer_value(jtVal);
			return true;
		}

		strErr = formatString("\"%s\" (type=%d) is not an integer value", pszKey, jtVal.Type());
	}

	return false;
}

/////////////////////////////////////////////////////////////////////////////

bool CMqttClConfig::GetStringValue(CJson_t &rjtParent, const char *pszKey, std::string &rstrVal, std::string &strErr)
{
	CJson_t jtVal;

	if(GetValue(rjtParent, pszKey, jtVal, strErr))
	{
		if(json_is_string(jtVal.operator const json_t*()))
		{
			rstrVal = ::json_string_value(jtVal);
			return true;
		}

		strErr = formatString("\"%s\" (type=%d) is not a string value", pszKey, jtVal.Type());
	}

	return false;
}

/////////////////////////////////////////////////////////////////////////////

sa_family_t CMqttClConfig::GetDevIdInterfaceName(char *pszItfName, size_t nCChItfName, const char *pszRequested)
{
	sa_family_t nFamily = 0;
	struct ifaddrs *ifaddr, *ifa;
	memset(pszItfName, 0, nCChItfName);

	if(getifaddrs(&ifaddr) == 0)
	{
		for(ifa = ifaddr; ifa != NULL; ifa = ifa->ifa_next)
		{
			if(!ifa->ifa_addr || (ifa->ifa_flags & IFF_LOOPBACK))
				continue;
			if(	ifa->ifa_addr->sa_family == AF_INET ||
				ifa->ifa_addr->sa_family == AF_INET6)
			{
				if(!strcmp(ifa->ifa_name, pszRequested))
				{
					strncpy(pszItfName, ifa->ifa_name, nCChItfName - 1);
					nFamily = ifa->ifa_addr->sa_family;
					break;
				}
				else if(!nFamily)
				{
					strncpy(pszItfName, ifa->ifa_name, nCChItfName - 1);
					nFamily = ifa->ifa_addr->sa_family;
				}
			}
		}

		freeifaddrs(ifaddr);
	}

	return nFamily;
}

const char* CMqttClConfig::GetMacAddress(std::string &s)
{
	int fd;
	struct ifreq ifr;
	s.clear();

	if((ifr.ifr_addr.sa_family = CMqttClConfig::GetDevIdInterfaceName(ifr.ifr_name, sizeof(ifr.ifr_name), "eth0")))
	{
		if((fd = socket(ifr.ifr_addr.sa_family, SOCK_DGRAM, 0)) >= 0)
		{
			if(	(ioctl(fd, SIOCGIFHWADDR, &ifr) == 0) &&
				(ifr.ifr_hwaddr.sa_family == ARPHRD_ETHER))
			{
				const char *m = (const char*)ifr.ifr_hwaddr.sa_data;
				s = formatString("%0.2hhX:%0.2hhX:%0.2hhX:%0.2hhX:%0.2hhX:%0.2hhX" , m[0], m[1], m[2], m[3], m[4], m[5]);
			}

			close(fd);
		}
	}

	return s.c_str();
}

std::string CMqttClConfig::CreateDeviceID(const char *pszDevicePrefix)
{
	std::string m, s;
	s = formatString("%s-%s", pszDevicePrefix, CMqttClConfig::GetMacAddress(m));
	return s;
}