/*
 *   Copyright (C) 2011-2014 by Jonathan Naylor G4KLX
 *   Copyright (c) 2017 by Thomas A. Early N7TAE
 *
 *   This program 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.
 *
 *   This program 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 this program; if not, write to the Free Software
 *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#include <sys/stat.h>
#include <cassert>
#include <cstring>
#include <cstdlib>
#include <stdio.h>
#include <fstream>
#include <cctype>
#include <string>

#include "DStarDefines.h"
#include "HeaderData.h"
#include "AudioUnit.h"
#include "Utils.h"

unsigned char* CAudioUnit::m_ambe = NULL;
unsigned int   CAudioUnit::m_ambeLength = 0U;
std::map<std::string, CIndexRecord *> CAudioUnit::m_index;

TEXT_LANG CAudioUnit::m_language = TL_ENGLISH_UK;

const unsigned int MAX_FRAMES = 60U * DSTAR_FRAMES_PER_SEC;

const unsigned int SILENCE_LENGTH = 10U;//Number of silence frames

void CAudioUnit::initialise()
{
}

void CAudioUnit::setLanguage(TEXT_LANG language)
{
	m_language = language;

	std::string ambeFileName;
	std::string indxFileName;

	switch (language) {
		case TL_DEUTSCH:
			ambeFileName = "de_DE.ambe";
			indxFileName = "de_DE.indx";
			break;
		case TL_DANSK:
			ambeFileName = "dk_DK.ambe";
			indxFileName = "dk_DK.indx";
			break;
		case TL_ITALIANO:
			ambeFileName = "it_IT.ambe";
			indxFileName = "it_IT.indx";
			break;
		case TL_FRANCAIS:
			ambeFileName = "fr_FR.ambe";
			indxFileName = "fr_FR.indx";
			break;
		case TL_ESPANOL:
			ambeFileName = "es_ES.ambe";
			indxFileName = "es_ES.indx";
			break;
		case TL_SVENSKA:
			ambeFileName = "se_SE.ambe";
			indxFileName = "se_SE.indx";
			break;
		case TL_POLSKI:
			ambeFileName = "pl_PL.ambe";
			indxFileName = "pl_PL.indx";
			break;
		case TL_ENGLISH_US:
			ambeFileName = "en_US.ambe";
			indxFileName = "en_US.indx";
			break;
		case TL_NORSK:
			ambeFileName = "no_NO.ambe";
			indxFileName = "no_NO.indx";
			break;
		default:
			ambeFileName = "en_GB.ambe";
			indxFileName = "en_GB.indx";
			break;
	}

	bool ret = readAMBE(ambeFileName);
	if (!ret) {
		delete[] m_ambe;
		m_ambe = NULL;
		return;
	}

	ret = readIndex(indxFileName);
	if (!ret) {
		delete[] m_ambe;
		m_ambe = NULL;
	}
}

void CAudioUnit::finalise()
{
	for (std::map<std::string, CIndexRecord *>::iterator it = m_index.begin(); it != m_index.end(); ++it)
		delete it->second;

	delete[] m_ambe;
}

CAudioUnit::CAudioUnit(CG2ProtocolHandler* handler) :
m_handler(handler),
// m_callsign(callsign),
m_encoder(),
m_status(AS_IDLE),
m_ackType(AT_LOGIN),
m_groupName(),
m_user(),
m_repeater(),
m_gateway(),
m_destination(),
m_timer(1000U, REPLY_TIME),
m_data(NULL),
m_in(0U),
m_out(0U),
m_seqNo(0U) //,
//m_time()
{
	assert(handler != NULL);

	m_data = new CAMBEData*[MAX_FRAMES];

	for (unsigned int i = 0U; i < MAX_FRAMES; i++)
		m_data[i] = NULL;
}

CAudioUnit::~CAudioUnit()
{
	delete[] m_data;
}

void CAudioUnit::sendAck()
{
	if (m_ambe == NULL)
		return;

	if (m_status != AS_IDLE)
		return;

	m_status = AS_WAIT;
	m_timer.start();
}

void CAudioUnit::setAck(ACK_TYPE ackType, const std::string& groupName, const std::string& user, const std::string& repeater, const std::string& gateway, const in_addr& destination)
{
	m_ackType = ackType;
	m_groupName = groupName;
	m_user = user;
	m_repeater = repeater;
	m_gateway = gateway;
	m_destination = destination;
}

void CAudioUnit::clock(unsigned int ms)
{
	m_timer.clock(ms);

	if (m_status == AS_WAIT && m_timer.hasExpired()) {

		sendAck(m_ackType, m_groupName, m_user, m_repeater, m_gateway, m_destination);

		m_timer.stop();

		m_out    = 0U;
		m_seqNo  = 0U;
		m_status = AS_TRANSMIT;

		m_time = std::chrono::high_resolution_clock::now();

		return;
	}

	if (m_status == AS_TRANSMIT) {
		std::chrono::high_resolution_clock::time_point hrctp = std::chrono::high_resolution_clock::now();
		auto elapse = std::chrono::duration_cast<std::chrono::milliseconds>(hrctp - m_time);
		unsigned int needed = elapse.count() / DSTAR_FRAME_TIME_MS;

		while (m_out < needed) {
			CAMBEData* data = m_data[m_out];
			m_data[m_out] = NULL;
			m_out++;

			if (m_in == m_out)
				data->setEnd(true);

			m_handler->writeAMBE(*data);

			delete data;

			if (m_in == m_out) {
				m_in     = 0U;
				m_out    = 0U;
				m_status = AS_IDLE;
				m_timer.stop();
				return;
			}
		}

		return;
	}
}

void CAudioUnit::cancel()
{
	for (unsigned int i = 0U; i < MAX_FRAMES; i++) {
		if (m_data[i] != NULL) {
			delete m_data[i];
			m_data[i] = NULL;
		}
	}

	m_status = AS_IDLE;
	m_out    = 0U;
	m_in     = 0U;

	m_timer.stop();
}

bool CAudioUnit::lookup(unsigned int id, const std::string &name, const in_addr& destination)
{
	CIndexRecord* info = m_index[name];
	if (info == NULL) {
		// wxLogError(wxT("Cannot find the AMBE index for *%s*"), name.c_str());
		return false;
	}

	unsigned int  start = info->getStart();
	unsigned int length = info->getLength();

	for (unsigned int i = 0U; i < length; i++) {
		unsigned char* dataIn = m_ambe + (start + i) * VOICE_FRAME_LENGTH_BYTES;

		CAMBEData* dataOut = new CAMBEData;
		dataOut->setSeq(m_seqNo);
		dataOut->setId(id);
		dataOut->setDestination(destination, G2_DV_PORT);

		unsigned char buffer[DV_FRAME_LENGTH_BYTES];
		memcpy(buffer + 0U, dataIn, VOICE_FRAME_LENGTH_BYTES);

		// Insert sync bytes when the sequence number is zero, slow data otherwise
		if (m_seqNo == 0U) {
			memcpy(buffer + VOICE_FRAME_LENGTH_BYTES, DATA_SYNC_BYTES, DATA_FRAME_LENGTH_BYTES);
			m_encoder.sync();
		} else {
			m_encoder.getTextData(buffer + VOICE_FRAME_LENGTH_BYTES);
		}

		dataOut->setData(buffer, DV_FRAME_LENGTH_BYTES);

		m_seqNo++;
		if (m_seqNo == 21)
			m_seqNo = 0;

		m_data[m_in] = dataOut;
		m_in++;
	}

	return true;
}

bool CAudioUnit::readAMBE(const std::string& name)
{
	std::string dir = DATA_DIR;
	std::string fileName = dir + "/" + name;
	struct stat sbuf;
	
	if (stat(fileName.c_str(), &sbuf)) {
		printf("File %s not readable\n", fileName.c_str());
		return false;
	}

	unsigned int fsize = sbuf.st_size;

	FILE *file = fopen(fileName.c_str(), "rb");
	if (NULL == file) {
		printf("Cannot open %s for reading\n", fileName.c_str());
		return false;
	}

	printf("Reading %s\n", fileName.c_str());

	unsigned char buffer[VOICE_FRAME_LENGTH_BYTES];

	size_t n = fread(buffer, 1, 4, file);
	if (n != 4) {
		printf("Unable to read the header from %s\n", fileName.c_str());
		fclose(file);
		return false;
	}

	if (memcmp(buffer, "AMBE", 4)) {
		printf("Invalid header from %s\n", fileName.c_str());
		fclose(file);
		return false;
	}

	// Length of the file minus the header length
	unsigned int length = fsize - 4U;

	// Hold the file data plus silence at the beginning
	m_ambe = new unsigned char[length + SILENCE_LENGTH * VOICE_FRAME_LENGTH_BYTES];
	m_ambeLength = (SILENCE_LENGTH + length) / VOICE_FRAME_LENGTH_BYTES;

	// Add silence to the beginning of the buffer
	unsigned char* p = m_ambe;
	for (unsigned int i = 0U; i < SILENCE_LENGTH; i++, p += VOICE_FRAME_LENGTH_BYTES)
		memcpy(p, NULL_AMBE_DATA_BYTES, VOICE_FRAME_LENGTH_BYTES);

	n = fread(p, 1, length, file);
	if (n != length) {
		printf("Unable to read the AMBE data from %s\n", fileName.c_str());
		fclose(file);
		delete[] m_ambe;
		m_ambe = NULL;
		return false;
	}

	fclose(file);

	return true;
}

bool CAudioUnit::readIndex(const std::string& name)
{
	std::string dir = DATA_DIR;
	std::string fileName = dir + "/" + name;
	struct stat sbuf;
	
	if (stat(fileName.c_str(), &sbuf)) {
		printf("File %s not readable\n", fileName.c_str());
		return false;
	}

	std::ifstream file(fileName);
	if (!file.is_open()) {
		printf("Cannot open %s for reading\n", fileName.c_str());
		return false;
	}

	// Add a silence entry at the beginning
	m_index[" "] = new CIndexRecord(" ", 0, SILENCE_LENGTH);

	printf("Reading %s\n", fileName.c_str());

	std::string line;
	while (std::getline(file, line)) {

		if (!line.empty() && '#'!=line[0]) {
			//ToDo F4FXL 2020-03-14 clean this up
			char linec[128];
			strcpy(linec, line.c_str());
			const std::string space(" \t\r\n");
			std::string name(strtok(linec, space.c_str()));
			std::string strt(strtok(NULL, space.c_str()));
			std::string leng(strtok(NULL, space.c_str()));
			///End ToDo

			if (name.size() && strt.size() && leng.size()) {
				unsigned long start  = std::stoul(strt);
				unsigned long length = std::stoul(leng);

				if (start >= m_ambeLength || (start + length) >= m_ambeLength)
					printf("The start or end for *%s* is out of range, start: %lu, end: %lu\n", name.c_str(), start, start + length);
				else
					m_index[name] = new CIndexRecord(name, start + SILENCE_LENGTH, length);
			}
		}
	}

	return true;
}

void CAudioUnit::sendAck(ACK_TYPE ackType, const std::string& groupName, const std::string& user, const std::string& repeater, const std::string& gateway, const in_addr& destination)
{
	unsigned int id = CHeaderData::createId();

	CHeaderData header(groupName, "    ", user, gateway, repeater);
	header.setDestination(destination, G2_DV_PORT);
	header.setId(id);

	lookup(id, " ", destination);

	switch (ackType)
	{
	case AT_LOGIN:
		m_encoder.setTextData("Logged in");
		lookup(id, "logged-in", destination);
		break;
	case AT_LOGOFF:
		m_encoder.setTextData("Logged off");
		lookup(id, "logged-off", destination);
		break;
	default:
		m_encoder.setTextData("Doh !");
		break;
	}

	lookup(id, " ", destination);

	spellGroup(id, groupName, destination);

	lookup(id, " ", destination);

	m_handler->writeHeader(header);
}

void CAudioUnit::spellGroup(unsigned int id, const std::string& groupName, const in_addr& destination)
{
	for(auto it = groupName.begin(); it != groupName.end();it++)
	{
		if((*it) ==' ')
		{
			continue;
		}
		std::string cstr;
		cstr.push_back(std::tolower((*it)));
		lookup(id, cstr, destination);
	}
}