#include "I2cComIF.h"
#include <fsfw/serviceinterface/ServiceInterface.h>

#include <unistd.h>
#include <fcntl.h>
#include <sys/ioctl.h>
#include <linux/i2c-dev.h>
#include <errno.h>
#include <string.h>


I2cComIF::I2cComIF(object_id_t objectId): SystemObject(objectId){
}

I2cComIF::~I2cComIF() {}

ReturnValue_t I2cComIF::initializeInterface(CookieIF * cookie) {

	address_t i2cAddress;
	std::string deviceFile;

	if(cookie == nullptr) {
		return NULLPOINTER;
	}
	I2cCookie* i2cCookie = dynamic_cast<I2cCookie*>(cookie);
	if(i2cCookie == nullptr) {
	    sif::error << "I2cComIF: Invalid I2C Cookie!"
	            << std::endl;
	    return NULLPOINTER;
	}

	i2cAddress = i2cCookie->getAddress();

	i2cDeviceMapIter = i2cDeviceMap.find(i2cAddress);
	if(i2cDeviceMapIter == i2cDeviceMap.end()) {
		size_t maxReplyLen = i2cCookie->getMaxReplyLen();
		I2cInstance_t i2cInstance = {std::vector<uint8_t>(maxReplyLen), 0};
		std::pair status = i2cDeviceMap.emplace(i2cAddress, i2cInstance);
		if (status.second == false) {
			sif::error << "I2cComIF::initializeInterface: Failed to insert "
					<< "device with address " << i2cAddress << "to I2C device "
					<< "map" << std::endl;
			return HasReturnvaluesIF::RETURN_OK;
		}
	}
	else {
		sif::error << "I2cComIF: Device with address " << i2cAddress
				<< "already in use" << std::endl;
	}

	i2cDeviceMapIter = i2cDeviceMap.find(i2cAddress);
	if(i2cDeviceMapIter == i2cDeviceMap.end()) {
		sif::error << "Failure" << std::endl;
	}

	return HasReturnvaluesIF::RETURN_OK;
}

ReturnValue_t I2cComIF::sendMessage(CookieIF *cookie,
        const uint8_t *sendData, size_t sendLen) {

	ReturnValue_t result;
	int fd;
	std::string deviceFile;

	if(sendData == nullptr) {
	    sif::error << "I2cComIF::sendMessage: Send Data is nullptr"
	            << std::endl;
	    return HasReturnvaluesIF::RETURN_FAILED;
	}

	if(sendLen == 0) {
		return HasReturnvaluesIF::RETURN_OK;
	}

	I2cCookie* i2cCookie = dynamic_cast<I2cCookie*>(cookie);
	if(i2cCookie == nullptr) {
		sif::error << "I2cComIF::sendMessasge: Invalid I2C Cookie!"
				<< std::endl;
		return NULLPOINTER;
	}

	address_t i2cAddress = i2cCookie->getAddress();
	i2cDeviceMapIter = i2cDeviceMap.find(i2cAddress);
	if (i2cDeviceMapIter == i2cDeviceMap.end()) {
		sif::error << "I2cComIF::sendMessage: i2cAddress of Cookie not "
				<< "registered in i2cDeviceMap" << std::endl;
		return HasReturnvaluesIF::RETURN_FAILED;
	}

	deviceFile = i2cCookie->getDeviceFile();
	result = openDevice(deviceFile, i2cAddress, &fd);
	if (result != HasReturnvaluesIF::RETURN_OK){
		return result;
	}

	if (write(fd, sendData, sendLen) != (int)sendLen) {
		sif::error << "I2cComIF::sendMessage: Failed to send data to I2C "
				"device with error code " << errno << ". Error description: "
				<< strerror(errno) << std::endl;
		close(fd);
		return HasReturnvaluesIF::RETURN_FAILED;
	}
	close(fd);
	return HasReturnvaluesIF::RETURN_OK;
}

ReturnValue_t I2cComIF::getSendSuccess(CookieIF *cookie) {
	return HasReturnvaluesIF::RETURN_OK;
}

ReturnValue_t I2cComIF::requestReceiveMessage(CookieIF *cookie,
		size_t requestLen) {

	ReturnValue_t result;
	int fd;
	std::string deviceFile;

	if (requestLen == 0) {
		return HasReturnvaluesIF::RETURN_OK;
	}

	I2cCookie* i2cCookie = dynamic_cast<I2cCookie*>(cookie);
	if(i2cCookie == nullptr) {
		sif::error << "I2cComIF::requestReceiveMessage: Invalid I2C Cookie!"
				<< std::endl;
		i2cDeviceMapIter->second.replyLen = 0;
		return NULLPOINTER;
	}

	address_t i2cAddress = i2cCookie->getAddress();
	i2cDeviceMapIter = i2cDeviceMap.find(i2cAddress);
	if (i2cDeviceMapIter == i2cDeviceMap.end()) {
		sif::error << "I2cComIF::requestReceiveMessage: i2cAddress of Cookie not "
				<< "registered in i2cDeviceMap" << std::endl;
		i2cDeviceMapIter->second.replyLen = 0;
		return HasReturnvaluesIF::RETURN_FAILED;
	}

	deviceFile = i2cCookie->getDeviceFile();
	result = openDevice(deviceFile, i2cAddress, &fd);
	if (result != HasReturnvaluesIF::RETURN_OK){
		i2cDeviceMapIter->second.replyLen = 0;
		return result;
	}

	uint8_t* replyBuffer = i2cDeviceMapIter->second.replyBuffer.data();

	if (read(fd, replyBuffer, requestLen) != (int)requestLen) {
		sif::error << "I2cComIF::requestReceiveMessage: Reading from I2C "
				<< "device failed with error code " << errno <<". Description"
				<< " of error: " << strerror(errno) << std::endl;
		close(fd);
		i2cDeviceMapIter->second.replyLen = 0;
		return HasReturnvaluesIF::RETURN_FAILED;
	}

	i2cDeviceMapIter->second.replyLen = requestLen;

	close(fd);

	return HasReturnvaluesIF::RETURN_OK;
}

ReturnValue_t I2cComIF::readReceivedMessage(CookieIF *cookie,
		uint8_t **buffer, size_t* size) {
	I2cCookie* i2cCookie = dynamic_cast<I2cCookie*>(cookie);
	if(i2cCookie == nullptr) {
		sif::error << "I2cComIF::readReceivedMessage: Invalid I2C Cookie!"
				<< std::endl;
		return NULLPOINTER;
	}

	address_t i2cAddress = i2cCookie->getAddress();
	i2cDeviceMapIter = i2cDeviceMap.find(i2cAddress);
	if (i2cDeviceMapIter == i2cDeviceMap.end()) {
		sif::error << "I2cComIF::readReceivedMessage: i2cAddress of Cookie not "
				<< "found in i2cDeviceMap" << std::endl;
		return HasReturnvaluesIF::RETURN_FAILED;
	}
	*buffer = i2cDeviceMapIter->second.replyBuffer.data();
	*size = i2cDeviceMapIter->second.replyLen;

	return HasReturnvaluesIF::RETURN_OK;
}

ReturnValue_t I2cComIF::openDevice(std::string deviceFile,
		address_t i2cAddress, int* fileDescriptor) {
	*fileDescriptor = open(deviceFile.c_str(), O_RDWR);
	if (*fileDescriptor < 0) {
		sif::error << "I2cComIF: Opening i2c device failed with error code "
				<< errno << ". Error description: " << strerror(errno)
				<< std::endl;
		return HasReturnvaluesIF::RETURN_FAILED;
	}

	if (ioctl(*fileDescriptor, I2C_SLAVE, i2cAddress) < 0) {
		sif::error << "I2cComIF: Specifying target device failed with error "
				<< "code " << errno << ". Error description "
				<< strerror(errno) << std::endl;
		return HasReturnvaluesIF::RETURN_FAILED;
	}
	return HasReturnvaluesIF::RETURN_OK;
}