#include <Preferences.h>

// Settings
int   TIMINGS[] = {-1,     1000,       5000,     10000     };
int   BUTTONS[] = {16,     17,     18,     19     };
int      LEDS[] = {27,     26,     25,     33     };
String COLORS[] = {"Grün", "Gelb", "Blau", "Weiss"};
String DESC = "GYBW";
int VALVE = 23;


// Variable Initialization
Preferences preferences;
String last_pressed = "";
String btn_edit_btn = "";
String mode = "";
int btn_edit_value = 0;
int time_target = 0;



int liters2time(int liters) {
  if (liters < 1) {
    return liters;
  }
  return liters * 1000;
}

int time2liters(int time) {
  if (time < 1) {
    return time;
  }
  return time / 1000;
}


void led_write(String active) {
  for (int i = 0; i < sizeof(LEDS) / sizeof(LEDS[0]); i++) {
    digitalWrite(LEDS[i], LOW);
  }

  for (int i = 0; i < active.length(); ++i) {
    digitalWrite(LEDS[DESC.indexOf(active[i])], HIGH);
  }
}

void startup_sequence() {
  led_write("G");
  delay(250);
  led_write("Y");
  delay(250);
  led_write("B");
  delay(250);
  led_write("W");
  delay(250);
  led_write("");
  delay(250);
  led_write("GYBW");
  delay(250);
  led_write("");
  delay(250);
  led_write("GYBW");
  delay(250);
  led_write("");
}

int get_timing(String button) {
  return preferences.getInt((button + "_TIMING").c_str());
}

void set_timing(String button, int value) {
  preferences.putInt((button + "_TIMING").c_str(), value);
}

String get_pressed() {
  String pressed = "";
  for (int i = 0; i < sizeof(BUTTONS) / sizeof(BUTTONS[0]); i++) {
    if (digitalRead(BUTTONS[i]) == HIGH) {
      pressed += DESC[i];
    }
  }
  return pressed;
}

void setup() {
  Serial.begin(115200);
  Serial.println("[DEBUG] Initializing...");

  preferences.begin("Water_Station", false); 

  pinMode(VALVE, OUTPUT);
  for (int i = 0; i < sizeof(BUTTONS) / sizeof(BUTTONS[0]); i++) {
    pinMode(BUTTONS[i], INPUT);
  }

  for (int i = 0; i < sizeof(LEDS) / sizeof(LEDS[0]); i++) {
    pinMode(LEDS[i], OUTPUT);
  }

  for (int i = 0; i < sizeof(TIMINGS) / sizeof(TIMINGS[0]); i++) {
    if (get_timing(String(DESC[i])) == 0) {
      set_timing(String(DESC[i]), TIMINGS[i]);
      Serial.print("[DEBUG] The Timing of ");
      Serial.print(COLORS[i]);
      Serial.println(" was not saved in Memory!");
    }
  }

  delay(250);
  led_write("");
  delay(250);

  startup_sequence();
  Serial.println("[DEBUG] Finished Initialization!");
}

void loop() {
  if (time_target != 0) {
    if (millis() > time_target) {
      time_target = 0;
      mode = "";
      led_write(mode);
      digitalWrite(VALVE, LOW);
    }
  }
  String pressed = get_pressed();
  if (last_pressed != pressed) {
    delay(50);
    pressed = get_pressed();
    last_pressed = pressed;
    if (pressed.length() == 0) {
      if (mode == "restart") {
        for (int i = 0; i < 10; ++i) {
          led_write("GYBW");
          delay(250);
          led_write("");
          delay(250);
        }
        ESP.restart();
      }
    } else {
      if (pressed.length() == 1) {
        if (mode == "") {
          mode = pressed;
          led_write(mode);
          int start_time = millis();
          digitalWrite(VALVE, HIGH);
          if (get_timing(mode) >= 0) {
            time_target = start_time + get_timing(mode);
          }
        } else if (mode == pressed){
          time_target = 0;
          mode = "";
          led_write(mode);
          digitalWrite(VALVE, LOW);
        } else if (mode == "btn_edit_select_btn") {
          btn_edit_btn = pressed;
          btn_edit_value = time2liters(get_timing(btn_edit_btn));
          mode = "btn_edit_select_value";
          led_write(btn_edit_btn);
          delay(500);
          led_write("");
        } else if (mode == "btn_edit_select_value") {
          if (pressed == "G") {
            if (btn_edit_value == -1) {
              led_write("GB");
              delay(500);
              led_write("");
            } else {
              int sub = 0;
              int values[DESC.length()];
              for (int i = DESC.length() - 1; i > 0; i--) {
                int power = pow(10, DESC.length() - i);
                int val = btn_edit_value % int(power) - sub;
                sub += val;
                values[i] = val / (power / 10);
              }
              while (true) {
                int sum = 0;
                for (int i = 1; i < sizeof values/sizeof values[0]; ++i) {
                  sum += values[i];
                }
                if (sum == 0) {
                  break;
                }
                String active = "";
                for (int i = 1; i < sizeof values/sizeof values[0]; ++i) {
                  if (values[i] != 0) {
                    active += DESC[i];
                    values[i] -= 1;
                  }
                }
                led_write(active);
                delay(250);
                led_write("");
                delay(250);
              }
            }
          } else {
            if (btn_edit_value == -1) {
              for (int i = 0; i < 5; ++i) {
                led_write("GB");
                delay(250);
                led_write("");
                delay(250);
              }
            } else {
              int modifier = pow(10, DESC.length() - DESC.indexOf(pressed));
              btn_edit_value = ((btn_edit_value + (modifier / 10)) % modifier) + (floor(btn_edit_value / modifier) * modifier);
              led_write(pressed);
              delay(100);
              led_write("");
            }
          }
        }
      } else {
        if (pressed == "GY") {
          led_write("GYBW");
          mode = "restart";
          Serial.println("[DEBUG] Restarting...");
        } else if (pressed == "GYBW") {
          for (int i = 0; i < DESC.length(); i++) {
            set_timing(String(DESC[i]), 0);
            led_write("GYBW");
            mode = "restart";
            Serial.println("[DEBUG] Resetting...");
          }
        } else if (mode == "") {
          if (pressed == "BW") {
            led_write("GYBW");
            mode = "btn_edit_select_btn";
          }
        } else if (mode == "btn_edit_select_value") {
          if (pressed == "BW") {
            set_timing(btn_edit_btn, liters2time(btn_edit_value));
            Serial.print("[DEBUG] Timing of Button ");
            Serial.print(COLORS[DESC.indexOf(btn_edit_btn)]);
            Serial.print(" was changed to ");
            Serial.print(liters2time(btn_edit_value));
            Serial.print(" (");
            Serial.print(btn_edit_value);
            Serial.println(" Liters).");
            mode = "";
            for (int i = 0; i < 2; ++i) {
              led_write("GYBW");
              delay(250);
              led_write("");
              delay(250);
            }
          } else if (pressed == "GB") {
            if (btn_edit_value == -1) {
              btn_edit_value = 0;
            } else {
              btn_edit_value = -1;
            }
            led_write("GB");
            delay(500);
            led_write("");
          }
        }
      }
    }
  }
}