WLED/wled00/util.cpp

#include "wled.h"
#include "fcn_declare.h"
#include "const.h"


//helper to get int value at a position in string
int getNumVal(const String* req, uint16_t pos)
{
  return req->substring(pos+3).toInt();
}


//helper to get int value with in/decrementing support via ~ syntax
void parseNumber(const char* str, byte* val, byte minv, byte maxv)
{
  if (str == nullptr || str[0] == '\0') return;
  if (str[0] == 'r') {*val = random8(minv,maxv?maxv:255); return;} // maxv for random cannot be 0
  bool wrap = false;
  if (str[0] == 'w' && strlen(str) > 1) {str++; wrap = true;}
  if (str[0] == '~') {
    int out = atoi(str +1);
    if (out == 0) {
      if (str[1] == '0') return;
      if (str[1] == '-') {
        *val = (int)(*val -1) < (int)minv ? maxv : min((int)maxv,(*val -1)); //-1, wrap around
      } else {
        *val = (int)(*val +1) > (int)maxv ? minv : max((int)minv,(*val +1)); //+1, wrap around
      }
    } else {
      if (wrap && *val == maxv && out > 0) out = minv;
      else if (wrap && *val == minv && out < 0) out = maxv;
      else { 
        out += *val;
        if (out > maxv) out = maxv;
        if (out < minv) out = minv;
      }
      *val = out;
    }
    return;
  } else if (minv == maxv && minv == 0) { // limits "unset" i.e. both 0
    byte p1 = atoi(str);
    const char* str2 = strchr(str,'~'); // min/max range (for preset cycle, e.g. "1~5~")
    if (str2) {
      byte p2 = atoi(++str2);           // skip ~
      if (p2 > 0) {
        while (isdigit(*(++str2)));     // skip digits
        parseNumber(str2, val, p1, p2);
        return;
      }
    }
  }
  *val = atoi(str);
}


bool getVal(JsonVariant elem, byte* val, byte vmin, byte vmax) {
  if (elem.is<int>()) {
		if (elem < 0) return false; //ignore e.g. {"ps":-1}
    *val = elem;
    return true;
  } else if (elem.is<const char*>()) {
    const char* str = elem;
    size_t len = strnlen(str, 12);
    if (len == 0 || len > 10) return false;
    parseNumber(str, val, vmin, vmax);
    return true;
  }
  return false; //key does not exist
}


bool updateVal(const char* req, const char* key, byte* val, byte minv, byte maxv)
{
  const char *v = strstr(req, key);
  if (v) v += strlen(key);
  else return false;
  parseNumber(v, val, minv, maxv);
  return true;
}


//append a numeric setting to string buffer
void sappend(char stype, const char* key, int val)
{
  char ds[] = "d.Sf.";

  switch(stype)
  {
    case 'c': //checkbox
      oappend(ds);
      oappend(key);
      oappend(".checked=");
      oappendi(val);
      oappend(";");
      break;
    case 'v': //numeric
      oappend(ds);
      oappend(key);
      oappend(".value=");
      oappendi(val);
      oappend(";");
      break;
    case 'i': //selectedIndex
      oappend(ds);
      oappend(key);
      oappend(SET_F(".selectedIndex="));
      oappendi(val);
      oappend(";");
      break;
  }
}


//append a string setting to buffer
void sappends(char stype, const char* key, char* val)
{
  switch(stype)
  {
    case 's': {//string (we can interpret val as char*)
      String buf = val;
      //convert "%" to "%%" to make EspAsyncWebServer happy
      //buf.replace("%","%%");
      oappend("d.Sf.");
      oappend(key);
      oappend(".value=\"");
      oappend(buf.c_str());
      oappend("\";");
      break;}
    case 'm': //message
      oappend(SET_F("d.getElementsByClassName"));
      oappend(key);
      oappend(SET_F(".innerHTML=\""));
      oappend(val);
      oappend("\";");
      break;
  }
}


bool oappendi(int i)
{
  char s[11];
  sprintf(s, "%d", i);
  return oappend(s);
}


bool oappend(const char* txt)
{
  uint16_t len = strlen(txt);
  if (olen + len >= SETTINGS_STACK_BUF_SIZE)
    return false;        // buffer full
  strcpy(obuf + olen, txt);
  olen += len;
  return true;
}


void prepareHostname(char* hostname)
{
  const char *pC = serverDescription;
  uint8_t pos = 5;

  while (*pC && pos < 24) { // while !null and not over length
    if (isalnum(*pC)) {     // if the current char is alpha-numeric append it to the hostname
      hostname[pos] = *pC;
      pos++;
    } else if (*pC == ' ' || *pC == '_' || *pC == '-' || *pC == '+' || *pC == '!' || *pC == '?' || *pC == '*') {
      hostname[pos] = '-';
      pos++;
    }
      // else do nothing - no leading hyphens and do not include hyphens for all other characters.
      pC++;
    }
    // if the hostname is left blank, use the mac address/default mdns name
    if (pos < 6) {
      sprintf(hostname + 5, "%*s", 6, escapedMac.c_str() + 6);
    } else { //last character must not be hyphen
      while (pos > 0 && hostname[pos -1] == '-') {
        hostname[pos -1] = 0;
        pos--;
      }
    }
}


bool isAsterisksOnly(const char* str, byte maxLen)
{
  for (byte i = 0; i < maxLen; i++) {
    if (str[i] == 0) break;
    if (str[i] != '*') return false;
  }
  //at this point the password contains asterisks only
  return (str[0] != 0); //false on empty string
}


//threading/network callback details: https://github.com/Aircoookie/WLED/pull/2336#discussion_r762276994
bool requestJSONBufferLock(uint8_t module)
{
  unsigned long now = millis();

  while (jsonBufferLock && millis()-now < 1000) delay(1); // wait for a second for buffer lock

  if (millis()-now >= 1000) {
    DEBUG_PRINT(F("ERROR: Locking JSON buffer failed! ("));
    DEBUG_PRINT(jsonBufferLock);
    DEBUG_PRINTLN(")");
    return false; // waiting time-outed
  }

  jsonBufferLock = module ? module : 255;
  DEBUG_PRINT(F("JSON buffer locked. ("));
  DEBUG_PRINT(jsonBufferLock);
  DEBUG_PRINTLN(")");
  fileDoc = &doc;  // used for applying presets (presets.cpp)
  doc.clear();
  return true;
}


void releaseJSONBufferLock()
{
  DEBUG_PRINT(F("JSON buffer released. ("));
  DEBUG_PRINT(jsonBufferLock);
  DEBUG_PRINTLN(")");
  fileDoc = nullptr;
  jsonBufferLock = 0;
}


// extracts effect mode (or palette) name from names serialized string
// caller must provide large enough buffer for name (incluing SR extensions)!
uint8_t extractModeName(uint8_t mode, const char *src, char *dest, uint8_t maxLen)
{
  if (src == JSON_mode_names || src == nullptr) {
    if (mode < strip.getModeCount()) {
      char lineBuffer[256];
      //strcpy_P(lineBuffer, (const char*)pgm_read_dword(&(WS2812FX::_modeData[mode])));
      strcpy_P(lineBuffer, strip.getModeData(mode));
      size_t len = strlen(lineBuffer);
      size_t j = 0;
      for (; j < maxLen && j < len; j++) {
        if (lineBuffer[j] == '\0' || lineBuffer[j] == '@') break;
        dest[j] = lineBuffer[j];
      }
      dest[j] = 0; // terminate string
      return strlen(dest);
    } else return 0;
  }

  uint8_t qComma = 0;
  bool insideQuotes = false;
  uint8_t printedChars = 0;
  char singleJsonSymbol;
  size_t len = strlen_P(src);

  // Find the mode name in JSON
  for (size_t i = 0; i < len; i++) {
    singleJsonSymbol = pgm_read_byte_near(src + i);
    if (singleJsonSymbol == '\0') break;
    if (singleJsonSymbol == '@' && insideQuotes && qComma == mode) break; //stop when SR extension encountered
    switch (singleJsonSymbol) {
      case '"':
        insideQuotes = !insideQuotes;
        break;
      case '[':
      case ']':
        break;
      case ',':
        if (!insideQuotes) qComma++;
      default:
        if (!insideQuotes || (qComma != mode)) break;
        dest[printedChars++] = singleJsonSymbol;
    }
    if ((qComma > mode) || (printedChars >= maxLen)) break;
  }
  dest[printedChars] = '\0';
  return strlen(dest);
}


// extracts effect slider data (1st group after @)
uint8_t extractModeSlider(uint8_t mode, uint8_t slider, char *dest, uint8_t maxLen)
{
  dest[0] = '\0'; // start by clearing buffer

  if (mode < strip.getModeCount()) {
    String lineBuffer = strip.getModeData(mode);
    if (lineBuffer.length() > 0) {
      int16_t start = lineBuffer.indexOf('@');
      int16_t stop  = lineBuffer.indexOf(';', start);
      if (start>0 && stop>0) {
        String names = lineBuffer.substring(start+1, stop);
        int16_t nameBegin = 0, nameEnd;
        for (size_t i=0; i<=slider; i++) {
          const char *tmpstr;
          dest[0] = '\0'; //clear dest buffer
          if (i > 0 && nameBegin == 0) break; // there are no more names
          nameEnd = names.indexOf(',', nameBegin);
          if (names.charAt(nameBegin) == '!') {
            switch (i) {
              case  0: tmpstr = PSTR("FX Speed");     break;
              case  1: tmpstr = PSTR("FX Intensity"); break;
              case  2: tmpstr = PSTR("FX Custom 1");  break;
              case  3: tmpstr = PSTR("FX Custom 2");  break;
              case  4: tmpstr = PSTR("FX Custom 3");  break;
              default: tmpstr = PSTR("FX Custom");    break;
            }
          } else {
            if (nameEnd<0) tmpstr = names.substring(nameBegin).c_str(); // did not find ",", last name?
            else           tmpstr = names.substring(nameBegin, nameEnd).c_str();
          }
          strncpy(dest, tmpstr, maxLen); // copy the name into buffer (replacing previous)
          nameBegin = nameEnd+1; // next name (if "," is not found it will be 0)
        } // next slider

        // we have slider name (including default value) in the dest buffer
        for (size_t i=0; i<strlen(dest); i++) if (dest[i]=='=') { dest[i]='\0'; break; } // truncate default value
        
      } else {
        // defaults to just speed and intensity since there is no slider data
        switch (slider) {
          case 0:  strncpy_P(dest, PSTR("FX Speed"), maxLen); break;
          case 1:  strncpy_P(dest, PSTR("FX Intensity"), maxLen); break;
        }
      }
    }
    return strlen(dest);
  }
  return 0;
}


uint16_t crc16(const unsigned char* data_p, size_t length) {
  uint8_t x;
  uint16_t crc = 0xFFFF;
  if (!length) return 0x1D0F;
  while (length--) {
    x = crc >> 8 ^ *data_p++;
    x ^= x>>4;
    crc = (crc << 8) ^ ((uint16_t)(x << 12)) ^ ((uint16_t)(x <<5)) ^ ((uint16_t)x);
  }
  return crc;
}