// variabili globali per tenere i parametri di ogni led  G giorno T tramont N notte A alba
// L  Light il tempo di salita, O il tempo di output, F  fading il tempo di discesa a 0

volatile  int LG = 0, LT = 0, LN = 0, LA = 0;
volatile  int OG = 0,  OT = 0, ON = 0, OA = 0;
volatile  int FG = 0,  FT = 0, FN = 0, FA = 0;


// variabili globali per la seriale
volatile char messageBuffer[10];
volatile uint8_t bufferIndex = 0;
volatile bool messageReady = false; 

void setupUSART9600NoParity() {
    // Set baud rate to 9600
    uint16_t ubrr_value = 103;  // (16,000,000 / (16 * 9600)) - 1 = 103
    UBRR0H = (uint8_t)(ubrr_value >> 8); // High byte of the baud rate
    UBRR0L = (uint8_t)(ubrr_value);      // Low byte of the baud rate

    // Enable receiver, transmitter, and RX complete interrupt
    UCSR0B = (1 << RXEN0) | (1 << TXEN0) | (1 << RXCIE0);

    // Set frame format: 8 data bits, 1 stop bit, no parity (8N1)
    UCSR0C = (1 << UCSZ01) | (1 << UCSZ00); // UCSZ01:0 = 11 for 8 data bits, no parity (UPM01 = 0, UPM00 = 0)

    // Enable global interrupts
    sei();
}

ISR(USART_RX_vect) {
    // ISR to handle the RX Complete interrupt
    char c = UDR0;  // Read the received character from the USART data register

    if (c == '\n' || c == '\r') { // End of message
        messageBuffer[bufferIndex] = '\0'; // Null-terminate the string
        messageReady = true;  // Set the flag to indicate a complete message
        bufferIndex = 0;      // Reset buffer index for the next message
    } else {
        if (bufferIndex < sizeof(messageBuffer) - 1) {
            messageBuffer[bufferIndex++] = c; // Store the character and increment the buffer index
        }
    }
}

bool parseAndValidateMessage(const char* message) {
    // Extract the prefix and number from the message
    char prefix[3] = {message[0], message[1], '\0'};
    int value = atoi(&message[2]);

    // Check that the value is less than 100
    if (value >= 100) {
        return false; // Invalid value, reject the message
    }

    // Assign the value to the appropriate variable based on the prefix
    if (strcmp(prefix, "LG") == 0) {
        LG = value;
    } else if (strcmp(prefix, "LT") == 0) {
        LT = value;
    } else if (strcmp(prefix, "LN") == 0) {
        LN = value;
    } else if (strcmp(prefix, "LA") == 0) {
        LA = value;
    } else if (strcmp(prefix, "OG") == 0) {
        OG = value;
    } else if (strcmp(prefix, "OT") == 0) {
        OT = value;
    } else if (strcmp(prefix, "ON") == 0) {
        ON = value;
    } else if (strcmp(prefix, "OA") == 0) {
        OA = value;
    } else if (strcmp(prefix, "FG") == 0) {
        FG = value;
    } else if (strcmp(prefix, "FT") == 0) {
        FT = value;
    } else if (strcmp(prefix, "FN") == 0) {
        FN = value;
    } else if (strcmp(prefix, "FA") == 0) {
        FA = value;
    } else {
        return false; // Invalid prefix, reject the message
    }

    return true; // Message is valid
}

void sendVariableStatus() {
    // Create a string to hold the status message
    char statusMessage[128];
    snprintf(statusMessage, sizeof(statusMessage), 
        "LG=%d, LT=%d, LN=%d, LA=%d, OG=%d, OT=%d, ON=%d, OA=%d, FG=%d, FT=%d, FN=%d, FA=%d\n",
        LG, LT, LN, LA, OG, OT, ON, OA, FG, FT, FN, FA);

    // Print the status message on the serial monitor
    for (uint8_t i = 0; statusMessage[i] != '\0'; i++) {
        while (!(UCSR0A & (1 << UDRE0))); // Wait until the transmit buffer is empty
        UDR0 = statusMessage[i]; // Transmit the character
    }
}

void sendInvalidMessage() {
    // Send the "message not valid" message
    const char* invalidMessage = "message not valid\n";
    for (uint8_t i = 0; invalidMessage[i] != '\0'; i++) {
        while (!(UCSR0A & (1 << UDRE0))); // Wait until the transmit buffer is empty
        UDR0 = invalidMessage[i]; // Transmit the character
    }
}

void setup() {
    // Initialize USART with interrupt and no parity bit
    setupUSART9600NoParity();
}

void loop() {
    static unsigned long lastUpdateTime = 0;
    unsigned long currentTime = millis();

    if (messageReady) {
        messageReady = false; // Clear the flag

        if (parseAndValidateMessage(messageBuffer)) {
            sendVariableStatus(); // Send the status of all variables if a valid message is received
        } else {
            sendInvalidMessage(); // Send an error message if parsing fails
        }
    }

    // Send the status every 5 seconds
    if (currentTime - lastUpdateTime >= 5000) {
        lastUpdateTime = currentTime;
        sendVariableStatus();
    }
   
    // Other code can go here, the main loop is not blocked by serial communication
}