#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>
#include <EEPROM.h>

#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 64
#define OLED_RESET -1
#define SCREEN_ADDRESS 0x3C

Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);

// Pins
#define SOIL_PIN A3
#define DRY_BUTTON_PIN 4
#define WET_BUTTON_PIN 5

// EEPROM addresses for storing calibration
#define EEPROM_DRY_HIGH 0
#define EEPROM_DRY_LOW 1
#define EEPROM_WET_HIGH 2
#define EEPROM_WET_LOW 3
#define EEPROM_MAGIC 4  // To check if EEPROM has been initialized

// Default calibration values
int dryValue = 800;
int wetValue = 300;

// Button debouncing
unsigned long lastDryPress = 0;
unsigned long lastWetPress = 0;
const unsigned long debounceDelay = 300;
bool lastDryState = HIGH;
bool lastWetState = HIGH;

// Plant bitmap dimensions
#define plant_width 32
#define plant_height 48

// ===== PASTE ALL YOUR BITMAP ARRAYS HERE =====
// Use https://berrydev-ai.github.io/berry-tools/bitmap-converter.html
// Generated bitmap arrays for 27 image(s)
// Generated on 11/27/2025, 9:28:41 AM

#include "plant_bitmaps.h"

void setup() {
  Serial.begin(9600);

  // Setup buttons with internal pullup resistors
  pinMode(DRY_BUTTON_PIN, INPUT_PULLUP);
  pinMode(WET_BUTTON_PIN, INPUT_PULLUP);

  // Load calibration from EEPROM
  loadCalibration();

  // Initialize display
  if (!display.begin(SSD1306_SWITCHCAPVCC, SCREEN_ADDRESS)) {
    Serial.println(F("SSD1306 allocation failed"));
    for (;;);
  }

  display.clearDisplay();
  display.setTextSize(1);
  display.setTextColor(SSD1306_WHITE);
  display.setCursor(0, 0);
  display.println(F("Soil Monitor"));
  display.println(F("Starting..."));
  display.display();
  delay(1000);

  Serial.println(F("Soil Monitor Ready"));
  Serial.print(F("Dry value: "));
  Serial.println(dryValue);
  Serial.print(F("Wet value: "));
  Serial.println(wetValue);
}

void loop() {
  // Check for button presses
  checkCalibrationButtons();

  // Read soil moisture
  int soilValue = analogRead(SOIL_PIN);

  // Map sensor value to 0-100% (inverted because lower reading = wetter)
  int moisturePercent = map(soilValue, dryValue, wetValue, 0, 100);
  moisturePercent = constrain(moisturePercent, 0, 100);

  // Map moisture to plant image index (0-26)
  int imageIndex = map(moisturePercent, 0, 100, 0, 26);
  imageIndex = constrain(imageIndex, 0, 26);

  // Clear display
  display.clearDisplay();

  // Draw text on left side
  display.setCursor(0, 0);
  display.setTextSize(1);
  display.println(F("Soil Monitor"));

  display.setCursor(0, 16);
  display.setTextSize(2);
  display.print(moisturePercent);
  display.println(F("%"));

  display.setCursor(0, 40);
  display.setTextSize(1);
  display.print(F("Raw:"));
  display.println(soilValue);

  if (moisturePercent < 30) {
    display.println(F("DRY!"));
  } else if (moisturePercent < 60) {
    display.println(F("OK"));
  } else {
    display.println(F("WET"));
  }

  // Draw plant image on right side
  display.drawBitmap(96, 8, plant_images[imageIndex], plant_width, plant_height, SSD1306_WHITE);

  // Update display
  display.display();

  // Debug output
  // Serial.print("Raw: ");
  // Serial.print(soilValue);
  // Serial.print(" | Moisture: ");
  // Serial.print(moisturePercent);
  // Serial.print("% | Image: ");
  // Serial.print(imageIndex);
  // Serial.print(" | DRY btn: ");
  // Serial.print(digitalRead(DRY_BUTTON_PIN));
  // Serial.print(" | WET btn: ");
  // Serial.println(digitalRead(WET_BUTTON_PIN));

  delay(500);
}

void checkCalibrationButtons() {
  unsigned long currentTime = millis();
  int soilValue = analogRead(SOIL_PIN);

  // Read current button states
  bool dryState = digitalRead(DRY_BUTTON_PIN);
  bool wetState = digitalRead(WET_BUTTON_PIN);

  // Check DRY button (trigger on button press, not release)
  // Only trigger if button went from HIGH to LOW (button was just pressed)
  if (dryState == LOW && lastDryState == HIGH &&
      (currentTime - lastDryPress) > debounceDelay) {
    lastDryPress = currentTime;

    // Set dry calibration to current reading
    dryValue = soilValue;
    saveCalibration();

    // Show confirmation
    showCalibrationMessage("DRY", dryValue);

    Serial.print(F("DRY calibrated to: "));
    Serial.println(dryValue);
  }

  // Check WET button (trigger on button press, not release)
  // Only trigger if button went from HIGH to LOW (button was just pressed)
  if (wetState == LOW && lastWetState == HIGH &&
      (currentTime - lastWetPress) > debounceDelay) {
    lastWetPress = currentTime;

    // Set wet calibration to current reading
    wetValue = soilValue;
    saveCalibration();

    // Show confirmation
    showCalibrationMessage("WET", wetValue);

    Serial.print(F("WET calibrated to: "));
    Serial.println(wetValue);
  }

  // Update last states
  lastDryState = dryState;
  lastWetState = wetState;
}

void showCalibrationMessage(const char* type, int value) {
  display.clearDisplay();
  display.setTextSize(2);
  display.setCursor(10, 10);
  display.println(type);
  display.println(F("SAVED!"));
  display.setTextSize(1);
  display.setCursor(10, 45);
  display.print(F("Value: "));
  display.println(value);
  display.display();
  delay(2000);
}

void saveCalibration() {
  // Save calibration values to EEPROM
  EEPROM.write(EEPROM_DRY_HIGH, highByte(dryValue));
  EEPROM.write(EEPROM_DRY_LOW, lowByte(dryValue));
  EEPROM.write(EEPROM_WET_HIGH, highByte(wetValue));
  EEPROM.write(EEPROM_WET_LOW, lowByte(wetValue));
  EEPROM.write(EEPROM_MAGIC, 42);  // Magic number to indicate EEPROM is initialized
}

void loadCalibration() {
  // Check if EEPROM has been initialized
  if (EEPROM.read(EEPROM_MAGIC) == 42) {
    // Load saved calibration
    dryValue = word(EEPROM.read(EEPROM_DRY_HIGH), EEPROM.read(EEPROM_DRY_LOW));
    wetValue = word(EEPROM.read(EEPROM_WET_HIGH), EEPROM.read(EEPROM_WET_LOW));

    Serial.println(F("Loaded calibration from EEPROM"));
  } else {
    // First time - use defaults and save them
    saveCalibration();
    Serial.println(F("Using default calibration"));
  }
}