/*
* © 2020, Chris Harlow. All rights reserved.
*
* This file is part of Asbelos DCC API
*
* This 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 3 of the License, or
* (at your option) any later version.
*
* It 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 CommandStation. If not, see .
*/
#include "WifiInterface.h"
#include "DIAG.h"
#include "StringFormatter.h"
#include "WiThrottle.h"
const char PROGMEM READY_SEARCH[] ="\r\nready\r\n";
const char PROGMEM OK_SEARCH[] ="\r\nOK\r\n";
const char PROGMEM END_DETAIL_SEARCH[] ="@ 1000";
const char PROGMEM PROMPT_SEARCH[] =">";
const char PROGMEM SEND_OK_SEARCH[] ="\r\nSEND OK\r\n";
const unsigned long LOOP_TIMEOUT=2000;
bool WifiInterface::connected=false;
bool WifiInterface::closeAfter=false;
DCCEXParser WifiInterface::parser;
byte WifiInterface::loopstate=0;
unsigned long WifiInterface::loopTimeoutStart=0;
int WifiInterface::datalength=0;
int WifiInterface::connectionId;
byte WifiInterface::buffer[MAX_WIFI_BUFFER];
MemStream WifiInterface::streamer(buffer,sizeof(buffer));
Stream * WifiInterface::wifiStream=NULL;
HTTP_CALLBACK WifiInterface::httpCallback=0;
void WifiInterface::setup(Stream & setupStream, const __FlashStringHelper* SSid, const __FlashStringHelper* password,
const __FlashStringHelper* hostname, const __FlashStringHelper* servername, int port) {
wifiStream=&setupStream;
DIAG(F("\n++++++ Wifi Setup In Progress ++++++++\n"));
connected=setup2( SSid, password,hostname, servername,port);
// TODO calloc the buffer and streamer and parser etc
DIAG(F("\n++++++ Wifi Setup %S ++++++++\n"), connected?F("OK"):F("FAILED"));
}
bool WifiInterface::setup2(const __FlashStringHelper* SSid, const __FlashStringHelper* password,
const __FlashStringHelper* hostname, const __FlashStringHelper* servername, int port) {
int ipOK=0;
delay(1000);
StringFormatter::send(wifiStream,F("AT+RST\r\n")); // reset module
checkForOK(5000,READY_SEARCH,false); // generally not interesting to DCC
StringFormatter::send(wifiStream,F("AT+GMR\r\n")); // request AT version
checkForOK(2000,OK_SEARCH,true); // Makes this visible on the console
StringFormatter::send(wifiStream,F("AT+CWMODE=1\r\n")); // configure as client
checkForOK(1000,OK_SEARCH,true); // Not always OK, sometimes "no change"
StringFormatter::send(wifiStream,F("AT+CIFSR\r\n"));
if(checkForOK(5000, (const char*) F("+CIFSR:STAIP"),true))
if(!checkForOK(1000, (const char*) F("0.0.0.0"),true))
ipOK=1;
if(!ipOK) {
StringFormatter::send(wifiStream,F("AT+CWMODE=3\r\n")); // configure as server or access point
checkForOK(1000,OK_SEARCH,true); // Not always OK, sometimes "no change"
// Older ES versions have AT+CWJAP, newer ones have AT+CWJAP_CUR and AT+CWHOSTNAME
StringFormatter::send(wifiStream,F("AT+CWJAP?\r\n"));
if (checkForOK(2000,OK_SEARCH,true)) {
// early version supports CWJAP
StringFormatter::send(wifiStream,F("AT+CWJAP=\"%S\",\"%S\"\r\n"),SSid,password);
checkForOK(20000,OK_SEARCH,true); // can ignore failure as AP mode may still be ok
}
else {
// later version supports CWJAP_CUR
StringFormatter::send(wifiStream, F("AT+CWHOSTNAME=\"%S\"\r\n"), hostname); // Set Host name for Wifi Client
checkForOK(2000, OK_SEARCH, true); // dont care if not supported
StringFormatter::send(wifiStream,F("AT+CWJAP_CUR=\"%S\",\"%S\"\r\n"),SSid,password);
checkForOK(20000,OK_SEARCH,true); // can ignore failure as AP mode may still be ok
StringFormatter::send(wifiStream,F("AT+CIPRECVMODE=0\r\n"),port); // make sure transfer mode is correct
checkForOK(2000,OK_SEARCH,true);
// StringFormatter::send(wifiStream, F("AT+MDNS=1,\"%S.local\",\"%S.local\",%d\r\n"), hostname, servername, port); // Setup mDNS for Server
// if (!checkForOK(5000, OK_SEARCH, true)) return false;
(void)servername; // avoid compiler warning from commented out AT_MDNS above
}
StringFormatter::send(wifiStream,F("AT+CIFSR\r\n")); // get ip address //192.168.4.1
if (!checkForOK(10000,OK_SEARCH,true)) return false;
}
StringFormatter::send(wifiStream,F("AT+CIPMUX=1\r\n")); // configure for multiple connections
if (!checkForOK(10000,OK_SEARCH,true)) return false;
StringFormatter::send(wifiStream,F("AT+CIPSERVER=1,%d\r\n"),port); // turn on server on port
if (!checkForOK(10000,OK_SEARCH,true)) return false;
return true;
}
void WifiInterface::ATCommand(const byte * command) {
StringFormatter:: send(wifiStream,F("AT+%s\r\n"), command+1);
checkForOK(10000,OK_SEARCH,true);
}
void WifiInterface::setHTTPCallback(HTTP_CALLBACK callback) {
httpCallback=callback;
}
bool WifiInterface::checkForOK( const unsigned int timeout, const char * waitfor, bool echo) {
unsigned long startTime = millis();
char const *locator=waitfor;
DIAG(F("\nWifi Check: [%E]"),waitfor);
while( millis()-startTime < timeout) {
while(wifiStream->available()) {
int ch=wifiStream->read();
if (echo) StringFormatter::printEscape(&DIAGSERIAL,ch); /// THIS IS A DIAG IN DISGUISE
if (ch!=pgm_read_byte_near(locator)) locator=waitfor;
if (ch==pgm_read_byte_near(locator)) {
locator++;
if (!pgm_read_byte_near(locator)) {
DIAG(F("\nFound in %dms"),millis()-startTime);
return true;
}
}
}
}
DIAG(F("\nTIMEOUT after %dms\n"),timeout);
return false;
}
bool WifiInterface::isHTTP() {
// POST GET PUT PATCH DELETE
// You may think a simple strstr() is better... but not when ram & time is in short supply
switch (buffer[0]) {
case 'P':
if (buffer[1]=='U' && buffer[2]=='T' && buffer[3]==' ' ) return true;
if (buffer[1]=='O' && buffer[2]=='S' && buffer[3]=='T' && buffer[4]==' ') return true;
if (buffer[1]=='A' && buffer[2]=='T' && buffer[3]=='C' && buffer[4]=='H' && buffer[5]==' ') return true;
return false;
case 'G':
if (buffer[1]=='E' && buffer[2]=='T' && buffer[3]==' ' ) return true;
return false;
case 'D':
if (buffer[1]=='E' && buffer[2]=='L' && buffer[3]=='E' && buffer[4]=='T' && buffer[5]=='E' && buffer[6]==' ') return true;
return false;
default:
return false;
}
}
void WifiInterface::loop() {
if (!connected) return;
WiThrottle::loop(); // check heartbeats
// read anything into a buffer, collecting info on the way
while (loopstate!=99 && wifiStream->available()) {
int ch=wifiStream->read();
// echo the char to the diagnostic stream in escaped format
// StringFormatter::printEscape(&DIAGSERIAL,ch); // DIAG in disguise
switch (loopstate) {
case 0: // looking for +IPD
connectionId=0;
if (ch=='+') loopstate=1;
break;
case 1: // Looking for I in +IPD
loopstate= (ch=='I')?2:0;
break;
case 2: // Looking for P in +IPD
loopstate= (ch=='P')?3:0;
break;
case 3: // Looking for D in +IPD
loopstate= (ch=='D')?4:0;
break;
case 4: // Looking for , After +IPD
loopstate= (ch==',')?5:0;
break;
case 5: // reading connection id
if (ch==',') loopstate=6;
else connectionId=10*connectionId+(ch-'0');
break;
case 6: // reading for length
if (ch==':') loopstate=(datalength==0)?99:7; // 99 is getout without reading next char
else datalength=datalength*10 + (ch-'0');
streamer.flush(); // basically sets write point at start of buffer
break;
case 7: // reading data
streamer.write(ch);
datalength--;
if (datalength==0) loopstate=99;
break;
case 10: // Waiting for > so we can send reply
if (millis()-loopTimeoutStart > LOOP_TIMEOUT) {
DIAG(F("\nWifi TIMEOUT on wait for > prompt or ERROR\n"));
loopstate=0; // go back to +IPD
break;
}
if (ch=='>'){
// DIAG(F("\n> [%e]\n"),buffer);
wifiStream->print((char *) buffer);
loopTimeoutStart=millis();
loopstate=closeAfter?11:0;
}
break;
case 11: // Waiting for SEND OK or ERROR to complete so we can closeAfter
if (millis()-loopTimeoutStart > LOOP_TIMEOUT) {
DIAG(F("\nWifi TIMEOUT on wait for SEND OK or ERROR\n"));
loopstate=0; // go back to +IPD
break;
}
if (ch=='K') { // assume its in SEND OK
StringFormatter::send(wifiStream,F("AT+CIPCLOSE=%d\r\n"),connectionId);
loopstate=0; // wait for +IPD
}
break;
} // switch
} // while
if (loopstate!=99) return;
// AT this point we have read an incoming message into the buffer
streamer.print('\0'); // null the end of the buffer so we can treat it as a string
DIAG(F("\n%d Wifi(%d)<-[%e]\n"),millis(),connectionId,buffer);
streamer.setBufferContentPosition(0,0); // reset write position to start of buffer
// SIDE EFFECT WARNING:::
// We know that parser will read the entire buffer before starting to write to it.
// Otherwise we would have to copy the buffer elsewhere and RAM is in short supply.
closeAfter=false;
// Intercept HTTP requests
if (isHTTP()) {
if (httpCallback) httpCallback(&streamer,buffer);
else {
StringFormatter::send(streamer,F("HTTP/1.1 404 Not Found\nContent-Type: text/html\nConnnection: close\n\n"));
StringFormatter::send(streamer,F("This is not a web server.
"));
}
closeAfter=true;
}
else if (buffer[0]=='<') parser.parse(&streamer,buffer, true); // tell JMRI parser that ACKS are blocking because we can't handle the async
else WiThrottle::getThrottle(connectionId)->parse(streamer, buffer);
if (streamer.available()==0) {
// No reply
if (closeAfter) StringFormatter::send(wifiStream,F("AT+CIPCLOSE=%d\r\n"),connectionId);
loopstate=0; // go back to waiting for +IPD
return;
}
// prepare to send reply
streamer.print('\0'); // null the end of the buffer so we can treat it as a string
DIAG(F("%d WiFi(%d)->[%e] l(%d)\n"),millis(),connectionId,buffer,streamer.available()-1);
StringFormatter::send(wifiStream,F("AT+CIPSEND=%d,%d\r\n"),connectionId,streamer.available()-1);
loopTimeoutStart=millis();
loopstate=10; // non-blocking loop waits for > before sending
}