#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>
#include <OneWire.h>
#include <DallasTemperature.h>

// Definición de pines
#define BUTTON_C 15
#define BUTTON_F 4
#define BUTTON_K 16
#define BUTTON_MODE 17
#define BUTTON_SAVE 18
#define LED_ALARM 32
#define LED_FULL 33
#define POT_PIN 34
#define ONE_WIRE_BUS 5

// Configuración del display OLED
#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 64
#define OLED_RESET -1
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);

// Configuración del sensor
OneWire oneWire(ONE_WIRE_BUS);
DallasTemperature sensors(&oneWire);

// Estructura para rangos de temperatura
struct TempRange {
    float min;
    float max;
};

// Rangos predeterminados para cada unidad
TempRange tempRanges[] = {
    {0, 100},     // Celsius
    {32, 212},    // Fahrenheit
    {273.15, 373.15}  // Kelvin
};

// Variables globales
enum TempUnit { CELSIUS, FAHRENHEIT, KELVIN };
enum DisplayMode { MEDICION, HISTORIAL, REFERENCIA, RANGO_MIN, RANGO_MAX };

// Variables para el manejo de interrupciones
volatile TempUnit currentUnit = CELSIUS;
volatile DisplayMode currentMode = MEDICION;
volatile bool saveRequested = false;
volatile bool modeChangeRequested = false;
volatile bool unitChangeRequested = false;
volatile TempUnit requestedUnit = CELSIUS;

// Variables para control de debounce
volatile unsigned long lastModeInterruptTime = 0;
volatile unsigned long lastUnitInterruptTime = 0;
volatile unsigned long lastSaveInterruptTime = 0;
const unsigned long DEBOUNCE_TIME = 200; // 200ms de debounce

// Variables normales
float tempHistory[5] = {0.00, 0.00, 0.00, 0.00, 0.00};
float referenceTemp = 50.0;
float currentTemp = 0.0;
float userRangeMin = 0.0;
float userRangeMax = 100.0;
float tempRefSet = 50.0;

// Función para convertir temperatura entre unidades
float convertTemperature(float temp, TempUnit fromUnit, TempUnit toUnit) {
    float tempC;
    switch(fromUnit) {
        case CELSIUS: tempC = temp; break;
        case FAHRENHEIT: tempC = (temp - 32) * 5.0/9.0; break;
        case KELVIN: tempC = temp - 273.15; break;
    }
    
    switch(toUnit) {
        case CELSIUS: return tempC;
        case FAHRENHEIT: return (tempC * 9.0/5.0) + 32;
        case KELVIN: return tempC + 273.15;
        default: return tempC;
    }
}

String getUnitSymbol(TempUnit unit) {
    switch(unit) {
        case CELSIUS: return "C";
        case FAHRENHEIT: return "F";
        case KELVIN: return "K";
        default: return "C";
    }
}

void saveTemperature() {
    if(currentMode == REFERENCIA && saveRequested) {
        tempRefSet = referenceTemp;
    }
    else if(currentMode == RANGO_MIN && saveRequested) {
        userRangeMin = referenceTemp;
    }
    else if(currentMode == RANGO_MAX && saveRequested) {
        if(referenceTemp > userRangeMin) {
            userRangeMax = referenceTemp;
        }
    }
    else {
        // Guardar en historial
        for(int i = 4; i > 0; i--) {
            tempHistory[i] = tempHistory[i-1];
        }
        tempHistory[0] = currentTemp;
    }
}

// ISRs para todos los botones
void IRAM_ATTR buttonCISR() {
    unsigned long currentTime = millis();
    if (currentTime - lastUnitInterruptTime > DEBOUNCE_TIME) {
        requestedUnit = CELSIUS;
        unitChangeRequested = true;
        lastUnitInterruptTime = currentTime;
    }
}

void IRAM_ATTR buttonFISR() {
    unsigned long currentTime = millis();
    if (currentTime - lastUnitInterruptTime > DEBOUNCE_TIME) {
        requestedUnit = FAHRENHEIT;
        unitChangeRequested = true;
        lastUnitInterruptTime = currentTime;
    }
}

void IRAM_ATTR buttonKISR() {
    unsigned long currentTime = millis();
    if (currentTime - lastUnitInterruptTime > DEBOUNCE_TIME) {
        requestedUnit = KELVIN;
        unitChangeRequested = true;
        lastUnitInterruptTime = currentTime;
    }
}

void IRAM_ATTR buttonModeISR() {
    unsigned long currentTime = millis();
    if (currentTime - lastModeInterruptTime > DEBOUNCE_TIME) {
        modeChangeRequested = true;
        lastModeInterruptTime = currentTime;
    }
}

void IRAM_ATTR saveButtonISR() {
    unsigned long currentTime = millis();
    if (currentTime - lastSaveInterruptTime > DEBOUNCE_TIME) {
        saveRequested = true;
        lastSaveInterruptTime = currentTime;
    }
}

// Función para procesar los cambios solicitados por interrupciones
void processInterruptRequests() {
    if (unitChangeRequested) {
        currentUnit = requestedUnit;
        unitChangeRequested = false;
    }
    
    if (modeChangeRequested) {
        currentMode = static_cast<DisplayMode>((currentMode + 1) % 5);
        modeChangeRequested = false;
    }
    
    if (saveRequested) {
        saveTemperature();
        saveRequested = false;
    }
}

bool isOutOfRange(float temp) {
    float convertedTemp = convertTemperature(temp, CELSIUS, currentUnit);
    return (convertedTemp < userRangeMin || convertedTemp > userRangeMax);
}

bool isAbove80Percent() {
    float currentRange = userRangeMax - userRangeMin;
    float threshold = userRangeMin + (currentRange * 0.8);
    float convertedTemp = convertTemperature(currentTemp, CELSIUS, currentUnit);
    return convertedTemp > threshold;
}

float readStabilizedPot() {
    const int numReadings = 10;
    float total = 0;
    for(int i = 0; i < numReadings; i++) {
        total += analogRead(POT_PIN);
        delay(1);
    }
    return total / numReadings;
}

float mapPotValueToTemp(float potValue, float minTemp, float maxTemp) {
    return map(potValue, 0, 4095, minTemp * 100, maxTemp * 100) / 100.0;
}

// Funciones de display
void displayMedicion() {
    display.setCursor(0, 0);
    display.println("MEDICION");
    display.setTextSize(2);
    display.setCursor(4, 18);
    
    float displayTemp = convertTemperature(currentTemp, CELSIUS, currentUnit);
    display.print(displayTemp, 2);
    display.print(" ");
    display.print(getUnitSymbol(currentUnit));

    if(isOutOfRange(currentTemp)) {
        display.setTextSize(1);
        display.setCursor(4, 45);
        display.println("FUERA DE RANGO");
    }
    
    display.setTextSize(1);
    display.setCursor(4, 55);
    display.print("Ref: ");
    display.print(convertTemperature(tempRefSet, CELSIUS, currentUnit), 1);
    display.print(getUnitSymbol(currentUnit));
}

void displayHistorial() {
    display.setCursor(0, 0);
    display.setTextSize(1);
    display.println("HISTORIAL");
    
    for(int i = 0; i < 5; i++) {
        display.setCursor(4, 12 + (i * 10));
        float displayTemp = convertTemperature(tempHistory[i], CELSIUS, currentUnit);
        display.print(displayTemp, 2);
        display.print(" ");
        display.print(getUnitSymbol(currentUnit));
    }
}

void displayReferencia() {
    display.setCursor(0, 0);
    display.setTextSize(1);
    display.println("REFERENCIA");
    display.setTextSize(2);
    display.setCursor(4, 18);
    display.print(referenceTemp, 2);
    display.print(" ");
    display.print(getUnitSymbol(currentUnit));
    
    display.setTextSize(1);
    display.setCursor(4, 45);
    display.print("SET: ");
    display.print(convertTemperature(tempRefSet, CELSIUS, currentUnit), 1);
    display.print(getUnitSymbol(currentUnit));
}

void displayRangoMin() {
    display.setCursor(0, 0);
    display.setTextSize(1);
    display.println("RANGO MINIMO");
    display.setTextSize(2);
    display.setCursor(4, 18);
    display.print(referenceTemp, 2);
    display.print(" ");
    display.print(getUnitSymbol(currentUnit));
    
    display.setTextSize(1);
    display.setCursor(4, 45);
    display.print("SET: ");
    display.print(convertTemperature(userRangeMin, CELSIUS, currentUnit), 1);
    display.print(getUnitSymbol(currentUnit));
}

void displayRangoMax() {
    display.setCursor(0, 0);
    display.setTextSize(1);
    display.println("RANGO MAXIMO");
    display.setTextSize(2);
    display.setCursor(4, 18);
    display.print(referenceTemp, 2);
    display.print(" ");
    display.print(getUnitSymbol(currentUnit));
    
    display.setTextSize(1);
    display.setCursor(4, 45);
    display.print("SET: ");
    display.print(convertTemperature(userRangeMax, CELSIUS, currentUnit), 1);
    display.print(getUnitSymbol(currentUnit));
}

void updateDisplay() {
    display.clearDisplay();
    display.setTextSize(1);
    display.setTextColor(SSD1306_WHITE);
    
    switch(currentMode) {
        case MEDICION: displayMedicion(); break;
        case HISTORIAL: displayHistorial(); break;
        case REFERENCIA: displayReferencia(); break;
        case RANGO_MIN: displayRangoMin(); break;
        case RANGO_MAX: displayRangoMax(); break;
    }
    
    display.display();
}

void setup() {
    // Configuración de pines
    pinMode(BUTTON_C, INPUT_PULLUP);
    pinMode(BUTTON_F, INPUT_PULLUP);
    pinMode(BUTTON_K, INPUT_PULLUP);
    pinMode(BUTTON_MODE, INPUT_PULLUP);
    pinMode(BUTTON_SAVE, INPUT_PULLUP);
    pinMode(LED_ALARM, OUTPUT);
    pinMode(LED_FULL, OUTPUT);
    
    // Configuración de interrupciones
    attachInterrupt(digitalPinToInterrupt(BUTTON_C), buttonCISR, FALLING);
    attachInterrupt(digitalPinToInterrupt(BUTTON_F), buttonFISR, FALLING);
    attachInterrupt(digitalPinToInterrupt(BUTTON_K), buttonKISR, FALLING);
    attachInterrupt(digitalPinToInterrupt(BUTTON_MODE), buttonModeISR, FALLING);
    attachInterrupt(digitalPinToInterrupt(BUTTON_SAVE), saveButtonISR, FALLING);
    
    // Inicialización del display
    if(!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) {
        Serial.println(F("SSD1306 allocation failed"));
        for(;;);
    }
    display.clearDisplay();
    
    // Inicialización del sensor
    sensors.begin();
    
    Serial.begin(115200);
}

void loop() {
    // Procesar las solicitudes de interrupciones
    processInterruptRequests();
    
    // Lectura de temperatura
    sensors.requestTemperatures();
    currentTemp = sensors.getTempCByIndex(0);
    
    // Control del LED de alarma
    digitalWrite(LED_ALARM, currentTemp >= tempRefSet ? HIGH : LOW);
    
    // Lectura y mapeo del potenciómetro según el modo
    float potValue = readStabilizedPot();
    switch(currentMode) {
        case REFERENCIA:
            referenceTemp = mapPotValueToTemp(potValue, 0, 100);
            break;
        case RANGO_MIN:
            referenceTemp = mapPotValueToTemp(potValue, -25, 0);
            break;
        case RANGO_MAX:
            referenceTemp = mapPotValueToTemp(potValue, 0, 100);
            break;
        default:
            break;
    }
    
    // Control del LED FULL
    if (isAbove80Percent()) {
        digitalWrite(LED_FULL, !digitalRead(LED_FULL));
    } else {
        digitalWrite(LED_FULL, LOW);
    }
    
    updateDisplay();
    delay(100);  // Delay para no sobrecargar el display
}