#include <WiFi.h>
#include <HardwareSerial.h>
#include "Telnet.h"
Telnet telnet;

#define SECRET_SSID "xxxxxxxxxxxx"
#define SECRET_PASS "xxxxxxxxxxxxx"

const uint8_t PRIMARY_DNS[4] = {192,168,11,1};
const uint8_t GATEWAY[4]     = {192,168,11,1};
const uint8_t SUBNETMASK[4]  = {255,255,255,0};
const uint8_t LOCAL_IP[4]    = {192,168,11,64};

#define TELNET_PORT (23)
WiFiServer server(TELNET_PORT);

HardwareSerial SerialPRN(1);

#define BAUDRATE_9600   (9600)
#define BAUDRATE_19200  (19200)
#define BAUDRATE_38400  (38400)

#define PIN_19200  A2
#define PIN_38400  A3

#define PRN_AS_289R  0x01
#define PRN_DP_EH600 0x02
#define PRN_AS_289R2 0x04

unsigned char prn_model;
int max_column = 48;
int row = 0;
int col = 4;
int numByte;

void printWifiStatus() {

	// print the SSID of the network you're attached to:
	telnet.print("SSID: %s\n",WiFi.SSID());

	// print your board's IP address:
	IPAddress ip = WiFi.localIP();
	telnet.print("IP Address: %d:%d;%d;%d\n",ip[0],ip[1],ip[2],ip[3]);

	// print the received signal strength:
	long rssi = WiFi.RSSI();
	telnet.print("signal strength (RSSI):%d  dBm\n",rssi);
}

void set_prn(HardwareSerial *prn)
{
	// 初期化(印字バッファ内データ抹消))
	prn->write(0x1b);
	prn->write(0x40);

	if (prn_model == PRN_DP_EH600) {
		max_column = 42;

		// Character font B (9*17)
		prn->write(0x1b);
		prn->write(0x21);
		prn->write(0x01);

		// Set line spacing
		prn->write(0x1b);
		prn->write(0x33);
		prn->write(0x14);
	}

	if ((prn_model == PRN_AS_289R)||(prn_model == PRN_AS_289R2)) {

		max_column = 48;

		// ANK文字フォント指定(8x16ドット)
		prn->write(0x1b);
		prn->write(0x68);
		prn->write(0x30);

		// 漢字フォント指定(16x16ドット)
		prn->write(0x12);
		prn->write(0x53);
		prn->write(0x31);

		// 文字コード指定(UTF-8)
		prn->write(0x1b);
		prn->write(0x24);
		prn->write(0x30);

		// 行間スペース量指定(0ドット)
		prn->write(0x1b);
		prn->write(0x41);
		prn->write(0x01);
	}

	// 文字間スペース量指定(0ドット)
	prn->write(0x1b);
	prn->write(0x20);
	prn->write((uint8_t)0x00);
}

void put_prn(Telnet *tn, HardwareSerial *prn)
{
	unsigned char ch;
	int i;

	while (telnet.available()) {
		if (row == 0) {
			tn->write(0x0a);
			prn->write(0x0d);
			prn->printf("%03d ",++row);
			tn->print("%03d ",row);
		}
		ch = telnet.read();
		switch(ch) {
			case 0x09: // TAB
				tn->write(' ');
				prn->write(' ');
				++col;
				break;
			case 0x0d:
				--col;
				break;
			case 0x0a:
				// 行末に改行コードがきた場合は、自動改行されるので無視する
				if ( col % max_column ) {
					tn->write(ch);
					prn->write(0x0d);
				}
				prn->printf("%03d ",++row);
				tn->print("%03d ",row);
				col = 4;
				break;
			case EOF: // EOF
			case 0x1a:
				tn->write(0x0a);
				tn->write(0x0a);
				prn->write(0x0d);
				prn->write(0x0d);
				prn->write(0x0d);
				row = 0;
				col = 4;
				return;
				break;
			default:
				if ((ch & 0x80) == 0x00) { // 1byte文字
					tn->write(ch);
					prn->write(ch);
					++col;
				} else {
					// 48桁目に2バイト文字がきた場合は、改行する
					if ( !((++col) % max_column)) {
						prn->write(0x0d);
						col = 2;
					} else {
						++col;
					}
					// UTF-8文字コードのバイト数判定
					if ((ch & 0xE0) == 0xC0)        { numByte=2; // 2byte文字
					} else if ((ch & 0xF0) == 0xE0) { numByte=3; // 3byte文字
					} else if ((ch & 0xF8) == 0xF0) { numByte=4; // 4byte文字
					} else if ((ch & 0xFC) == 0xF8) { numByte=5; // 5byte文字
					} else if ((ch & 0xFE) == 0xFC) { numByte=6; // 6byte文字
					} else { numByte=0;
					}
					if ((prn_model == PRN_AS_289R)||(prn_model == PRN_AS_289R2)) {
						tn->write(ch);
						prn->write(ch);
					} else {
						tn->write('?');
						prn->write('?');
					}
					for(i=1;i<numByte;) {
						if (tn->available()) {
							ch = tn->read();
							if ((prn_model == PRN_AS_289R)||(prn_model == PRN_AS_289R2)) {
								tn->write(ch);
								prn->write(ch);
							}
							i++;
						} else {
							delay(10);
						}
					}
				}
				break;
		}
		if (!(col % max_column)) {
			// AS-289R2は自動改行される
			tn->write(0x0a);
			if ((prn_model == PRN_AS_289R)||(prn_model == PRN_AS_289R2)) prn->write(0x0a);
		}
	}
}

void setup() 
{
	pinMode(PIN_19200, INPUT);
	pinMode(PIN_38400, INPUT);

	if (!WiFi.config(LOCAL_IP, GATEWAY, SUBNETMASK, PRIMARY_DNS)) while(1);

	// WiFi STA設定
	WiFi.mode(WIFI_STA);
	WiFi.begin(SECRET_SSID, SECRET_PASS); // Connect to WPA/WPA2 network
	while (WiFi.status() != WL_CONNECTED) delay(100);

	server.begin();
	telnet.begin(&server);
	printWifiStatus();

	if (digitalRead(PIN_19200) == LOW) {
		prn_model = PRN_DP_EH600;
		SerialPRN.begin(BAUDRATE_19200);
		telnet.print("DP-EH600 detected!\n");
	} else if (digitalRead(PIN_38400) == LOW) {
		prn_model = PRN_AS_289R2;
		SerialPRN.begin(BAUDRATE_38400);
		telnet.print("AS-289R2 detected!\n");
	} else {
		prn_model = PRN_AS_289R;
		SerialPRN.begin(BAUDRATE_9600);
		telnet.print("JP-QR204 detected!\n");
	}
	set_prn(&SerialPRN);
}

void loop()
{
	if (telnet.connected()) {
		put_prn(&telnet, &SerialPRN);
	} else {
		telnet.begin(&server);
		printWifiStatus();
		row = 0;
		col = 4;
	}
}

#ifndef __TELNET_H
#define __TELNET_H

#include <WiFi.h>

#define DEBUG_BUF_SIZE  256

class Telnet
{
	private:
		WiFiServer     *tnServer;
		WiFiClient     client;
		char           buf[DEBUG_BUF_SIZE];
		unsigned char  ch;

	public:
		Telnet();
		~Telnet();
		void begin(WiFiServer *tnserver);
		void print(const char* format, ...);
		void write(unsigned char ch);
		boolean available();
		boolean connected();
		unsigned char read();
};

#endif /*__TELNET_H*/

#include "Telnet.h"

Telnet::Telnet()
{
	tnServer = NULL;
	client   = NULL;
}

Telnet::~Telnet() {}

void Telnet::begin(WiFiServer *tnserver)
{
	tnServer = tnserver;

	unsigned char negotiation[25] = {
		0xFF,0xFB,0x03, // IAC WILL suppress_go_ahead
		0xFF,0xFD,0x01, // IAC DO   echo
		0xFF,0xFD,0x1F, // IAC DO   window_size
		0xFF,0xFB,0x05, // IAC WILL status
		0xFF,0xFD,0x21, // IAC DO   remote_flow_control
		0xFF,0xFD,0x18, // IAC DO   terminal_type
		0xFF,0xFD,0x03, // IAC DO   suppress_go_ahead
		0xFF,0xFB,0x01, // IAC WILL echo
	};

	client = tnServer->available();

	while(1) {
		if(client) {
			if (client.connected()) {
				while (client.available()) client.read();
				for(int i=0;i<24;++i) client.write(negotiation[i]);
				while (client.available()) client.read();
				return;
			}
		}
		client = tnServer->available();
		delay(100);
	}
}

boolean Telnet::connected()
{
	if (client && client.connected()) return true;
	else                              return false;
}

boolean Telnet::available()
{
	if (connected()) {
		while (client.available()) {
			ch = client.read();
			if (ch==0xFF) {
				ch = client.read();
				switch(ch) {
					case 0xF0: 
						break;
					case 0xFA: 
						for(int i=0;i<5;++i) ch = client.read();
						break;
					default:
						ch = client.read();
						break;
				}
				return false;
			} else {
				return true;
			}
		}
	}
	return false;
}

void Telnet::print(const char* format, ...)
{
	va_list args;
	va_start(args, format);
	vsprintf(buf,format,args);
	va_end(args);

	if (client.connected()) {
		for (int len = 0; buf[len]; len++) client.write(buf[len]);
	}
}

void Telnet::write(unsigned char uch)
{
	client.write(uch);
}

unsigned char Telnet::read()
{
	return ch;
}