#include <Arduino.h>
#include <DHT.h>
#include "esp_sleep.h"

// Pin Configuration
#define DHTPIN 14          // DHT22 sensor data pin
#define DHTTYPE DHT22      // DHT type
#define BUZZER_PIN 16      // Buzzer pin
#define SLIDE_RIGHT_SWITCH 4  // Right switch for waking up
#define SLIDE_LEFT_SWITCH 2   // Left switch for sleep mode

// RGB Pins (Pins with PWM support for analogWrite)
#define PIN_RED 17
#define PIN_GREEN 5
#define PIN_BLUE 18

// Debouncing Variables
volatile unsigned long lastRightSwitchTime = millis(); // Last right switch toggle timestamp
volatile unsigned long currentRightTime;
volatile unsigned long lastLeftSwitchTime = millis();  // Last left switch toggle timestamp
volatile unsigned long currentLeftTime;

// DHT sensor
DHT dht(DHTPIN, DHTTYPE);

// System state counters
volatile int Offcount = 0; // Count for the OFF state
volatile int Oncount = 0;  // Count for the ON state

// Function to set RGB LED color using analogWrite (PWM)
void setColor(int R, int G, int B) {
    analogWrite(PIN_RED, R);    // Red (0 to 255 brightness)
    analogWrite(PIN_GREEN, G);  // Green (0 to 255 brightness)
    analogWrite(PIN_BLUE, B);   // Blue (0 to 255 brightness)
}

// Interrupt Service Routine for the right switch (Wake-up)
void IRAM_ATTR switchTurnedRight() {
    currentRightTime = millis();
    if (currentRightTime - lastRightSwitchTime > 200) { // Debounce delay
        Oncount++; // Increment On count when the system is turned on
        Offcount = 0; // Reset Off count
        setColor(255, 255, 255); // Turn the RGB ON (white, can be customized)
        lastRightSwitchTime = currentRightTime;
    }
}

// Interrupt Service Routine for the left switch (Sleep)
void IRAM_ATTR switchTurnedLeft() {
    currentLeftTime = millis();
    if (currentLeftTime - lastLeftSwitchTime > 200) { // Debounce delay
        Offcount++; // Increment Off count when the system is turned off
        Oncount = 0; // Reset On count
        setColor(0, 0, 0);  // Turn the RGB OFF (black)
        lastLeftSwitchTime = currentLeftTime;
        enterDeepSleep(); // Put the system to deep sleep
    }
}

// Function to put ESP32 into deep sleep
void enterDeepSleep() {
    setColor(0, 0, 0); // Ensure RGB is off before sleep

    delay(100); // Small delay before sleep

    // Configure right switch as wake-up source
    esp_sleep_enable_ext0_wakeup((gpio_num_t)SLIDE_RIGHT_SWITCH, 1); // Wake up when right switch is pressed

    // Enter deep sleep
    esp_deep_sleep_start();
}

void setup() {
    Serial.begin(115200);
    dht.begin();

    // Pin setup
    pinMode(PIN_RED, OUTPUT);
    pinMode(PIN_GREEN, OUTPUT);
    pinMode(PIN_BLUE, OUTPUT);
    pinMode(BUZZER_PIN, OUTPUT);
    pinMode(SLIDE_RIGHT_SWITCH, INPUT);  // Internal pull-up for right switch
    pinMode(SLIDE_LEFT_SWITCH, INPUT);   // Internal pull-up for left switch

    // Attach interrupts for slide switches
    attachInterrupt(digitalPinToInterrupt(SLIDE_RIGHT_SWITCH), switchTurnedRight, FALLING); // Right slide switch
    attachInterrupt(digitalPinToInterrupt(SLIDE_LEFT_SWITCH), switchTurnedLeft, FALLING);  // Left slide switch

    // If waking up from deep sleep, the LED should remain off until right switch is toggled
    if (esp_sleep_get_wakeup_cause() == ESP_SLEEP_WAKEUP_EXT0) {
        Serial.println("Woke up from deep sleep.");
        Oncount++;  // The system is now active
        setColor(255, 255, 255);  // Turn RGB ON upon wakeup
    } else {
        Serial.println("System started in sleep mode.");
        Offcount = 1;  // System starts in sleep mode
        setColor(0, 0, 0);  // Ensure RGB is OFF initially
    }

    // Initially, the system is in sleep mode, so the RGB should be off
    if (Offcount > Oncount) {
        setColor(0, 0, 0); // Turn RGB OFF
    }
}

void loop() {
    // If the system is not active (in sleep mode), do nothing
    if (Offcount > Oncount) {
        return; // The system is sleeping, nothing happens here
    }

    // Measure humidity and temperature if the system is active
    float temperature = dht.readTemperature();
    float humidity = dht.readHumidity();

    // Print temperature and humidity to the Serial Monitor
    Serial.print("Temperature: ");
    Serial.print(temperature);
    Serial.print(" C, ");
    Serial.print("Humidity: ");
    Serial.print(humidity);
    Serial.println(" %");

    // If the sensor fails to read values, skip the loop
    if (isnan(temperature) || isnan(humidity)) {
        return; 
    }

    // RGB LED color logic based on humidity
    if (humidity < 30) {
        setColor(0, 0, 255);  // Blue: Low humidity
    } else if (humidity >= 30 && humidity <= 50) {
        setColor(0, 255, 0);  // Green: Normal humidity
    } else {
        setColor(255, 0, 0);  // Red: High humidity
        tone(BUZZER_PIN, 1000);  // 1kHz beep
    }

    // If humidity goes back down, turn off the buzzer
    if (humidity <= 50) {
        noTone(BUZZER_PIN);  // Turn off buzzer if humidity is back to normal
    }

    delay(2000);  // Sensor delay
}