class AppointmentScheduler:
    def __init__(self):
        self.state = "greeting"
        self.patient_info = {}

    def handle_incoming_speech(self, full_sentence):
        self.transcription_response = full_sentence.lower()

        if "goodbye" in self.transcription_response:
            return "Goodbye! Have a great day!"

        if self.state == "greeting":
            llm_response = "Good morning! Thank you for calling Dr. Smith's office. How can I assist you today?"
            self.state = "collecting_name"

        elif self.state == "collecting_name":
            if len(self.transcription_response.split()) >= 2:  # Basic check for full name
                llm_response = "I’d be happy to help you book an appointment. Can I have your full name, please?"
                self.state = "collecting_contact"
            else:
                llm_response = "Could you please provide your full name?"

        elif self.state == "collecting_contact":
            if self.validate_name(self.transcription_response):  # Validate name
                self.patient_info['name'] = self.transcription_response
                llm_response = "Thank you. Can I have your contact number, please?"
                self.state = "understanding_needs"
            else:
                llm_response = "Sorry, I didn't get that. Could you please repeat your full name?"

        elif self.state == "understanding_needs":
            if self.validate_phone_number(self.transcription_response):  # Validate phone number
                self.patient_info['contact'] = self.transcription_response
                llm_response = "What is the reason for your visit? This helps us allocate the right amount of time for your appointment."
                self.state = "checking_availability"
            else:
                llm_response = "That doesn't seem to be a valid contact number. Please provide a valid phone number."

        elif self.state == "checking_availability":
            self.patient_info['reason'] = self.transcription_response
            llm_response = "When would you prefer to schedule your appointment? I’ll check the available slots for that day."
            self.state = "confirming_appointment"

        elif self.state == "confirming_appointment":
            self.patient_info['preferred_time'] = self.transcription_response
            llm_response = "I have received your request. Please wait while I check availability."
            # Add logic for checking appointment availability

            # Proceed with state transition
            self.state = "providing_additional_info"

        elif self.state == "providing_additional_info":
            llm_response = "Is there anything else I can help you with today? If you have any questions before your appointment, feel free to call us."
            self.state = "greeting"

        else:
            llm_response = "I'm sorry, I didn’t understand that. Could you please clarify?"

        return llm_response

    def validate_phone_number(self, phone_number):
        # Placeholder validation logic
        return True if len(phone_number) == 10 and phone_number.isdigit() else False

    def validate_name(self, name):
        return True if len(name.split()) >= 2 else False