/*

   Reading lines from SD card
   Comparing each line with the entries of a given string array
   Calls the related function (if found)

   This version uses char arrays / c strings


   Forum: https://forum.arduino.cc/t/help-text-file-to-function-calls/1154798/4
   Wokwi: https://wokwi.com/projects/372306615255913473

  ec2021
  2023-08-06

*/

#include <SD.h>
#define CS_PIN 10



void sinelon() {
  Serial.println("Calling sinelon!");
  delay(2000);
}

void stranger() {
  Serial.println("Calling stranger!");
  delay(2000);
}

void rainbowWithGlitter() {
  Serial.println("Calling rainbowWithGlitter!");
  delay(2000);
}

// Make sure that the Sequence list is in the same order and length as the
// pattern function list and to use the identical names in this array and
// in the SD card text file!
//


typedef void (*SimplePatternList[])();
SimplePatternList gPatterns = { sinelon, stranger, rainbowWithGlitter};

constexpr byte noOfSeq = 3;
constexpr char *Sequence[noOfSeq] = {
  "sinelon", "stranger", "rainbowWithGlitter"
};

void setup() {
  Serial.begin(115200);
  Serial.print(F("Initializing SD card... "));
  if (!SD.begin(CS_PIN)) {
    Serial.println(F("Card initialization failed!"));
    while (true);
  }
  Serial.println(F("initialization done.\n-------------------------------------------\n\n"));
  readSequence();
  Serial.println(F("-------------------------------------------"));
  Serial.println(F("End of Sequences"));
}

void loop() {
  // nothing happens after setup finishes.
}


void readSequence() {
  constexpr byte cLen = 40;
  char aLine[cLen + 1];
  aLine[cLen] = '\0';
  File textFile = SD.open(F("sequence.txt"));
  int i = 0;
  if (textFile) {
    while (textFile.available()) {
      char c = textFile.read();
      if (i >= cLen) {
        i = 0;
      }
      if (c >= ' ') {
        aLine[i] = c;
        i++;
      }
      if (c == 10 && i > 0) {
        aLine[i] = '\0';
        compare(aLine);
        i = 0;
      }
    }
    textFile.close();
    if (i > 0) {
      aLine[i - 1] = '\0';
      compare(aLine);
    }
  }  else {
    Serial.println(F("error opening sequence.txt"));
  }
}


void compare(char * line) {
  int No = -1;
  for (int i = 0; i < noOfSeq; i++) {
    if (strcmp(line, Sequence[i]) == 0 ) {
      No = i;
    }
  }
  char buf[80];
  sprintf(buf, "%-25s relates to ", line);
  Serial.print(buf);
  if (No != -1) {
    Serial.println(No);
    gPatterns[No]();
    //
    // This is where further action can be taken
    //
    // "No" equals gCurrentPatterNumber
  } else {
    Serial.println("-");
    Serial.println(F("Calling nothing .... ;-) "));
    delay(2000);
  }
}