client.py

import socket
import os
import sys
import hashlib

HOST = "127.0.0.1"
HOSPITAL_TCP_PORT = 26860

# get hash value of string
def sha256_hash(text: str) -> str:
    text = text.strip()
    return hashlib.sha256(text.encode('utf-8')).hexdigest()


def main():
    # Define tcp socket
    tcp_sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    tcp_sock.connect((HOST, HOSPITAL_TCP_PORT))
    client_port = tcp_sock.getsockname()[1]

    print(f"The client is up and running.")

    # Get client credentials
    username = sys.argv[1]
    username_hash = sha256_hash(sys.argv[1])
    password_hash = sha256_hash(sys.argv[2])
    user_credentials = (f"{username_hash}:{password_hash}")
    user_status = None

    # Send authentication request to hospital server
    print(f"{username} sent an authentication request to the hospital server.")
    tcp_sock.sendall(user_credentials.encode())

    # Receive authentication response from hospital server
    user_role = tcp_sock.recv(1024).decode()

    # Check user status
    if(user_role == "PATIENT"):
        user_status = "PATIENT"
        print(f"{username} received the authentication result. Authentication successful. You have been granted patient access.")
    elif(user_role == "DOCTOR"):
        user_status = "DOCTOR"
        print(f"{username} received the authentication result. Authentication successful. You have been granted doctor access.")
    else:
        print(f"The credentials are incorrect. Please try again.")
        tcp_sock.close()
        return


    try:
        while True:
            # Wait for command input from the user
            command = input()
            command_list = command.strip().split(" ")

            # quit command
            if(len(command_list) == 1 and command_list[0] == "quit"):
                print(f"You have successfully been logged out.\n——Quit Program——")
                tcp_sock.close()
                sys.exit(0)
                    
            # patient commands
            if user_status == "PATIENT":
                # lookup
                if(len(command_list) == 1 and command_list[0] == "lookup"):
                    print(f"{username} sent a lookup request to the hospital server.")
                    tcp_sock.sendall("LOOKUP|lookup".encode())
                    list_of_doctors = tcp_sock.recv(1024).decode().strip().split(" ")
                    print(f"The client received the response from the hospital server using TCP over port {client_port}.\nThe following doctors are available: ")
                    for doctor in list_of_doctors:
                        print(f"{doctor}")
                
                # lookup <doctor>
                elif(len(command_list) == 2 and command_list[0] == "lookup" and command_list[1].startswith("Dr.")):
                    print(f"Patient {username} sent a lookup request to the hospital server for {command_list[1]}.")
                    tcp_sock.sendall((f"LOOKUP_DR|{command_list[1]}").encode())
                    available_timeslots = tcp_sock.recv(1024).decode().strip().split(" ")
                    if len(available_timeslots) == 8:
                        print(f"The client received the response from the hospital server using TCP over port {client_port}.\nAll time blocks are available for {command_list[1]}.")
                    elif len(available_timeslots) == 1 and available_timeslots[0] == "NO_SLOT":
                        print(f"The client received the response from the Hospital Server using TCP over port {client_port}.\n{command_list[1]} has no time slots available.")
                    else:
                        print(f"The client received the response from the Hospital Server using TCP over port {client_port}.\n{command_list[1]} is available at times: ")
                        for slot in available_timeslots:
                            print(f"{slot}")
                
                # schedule
                elif(len(command_list) == 4 and command_list[0] == "schedule"):
                    tcp_sock.sendall((f"SCHEDULE|{command_list[1]} {command_list[2]} {command_list[3]}").encode())
                    print(f"{username} sent an appointment schedule request to the hospital server.")
                    schedule_result = tcp_sock.recv(1024).decode().strip().split(" ")

                    if len(schedule_result) == 1 and schedule_result[0] == "APPOINTMENT_SCHEDULED_SUCCESSFULLY":
                        print(f"The client received the response from the Hospital Server using TCP over port {client_port}\nAn appointment has been successfully scheduled for patient {username} with {command_list[1]} at {command_list[2]}.")
                    elif len(schedule_result) == 1 and schedule_result[0] == "INCORRECT_INPUT_FORMAT":
                        print(f"INCORRECT INPUT FORMAT FOR SCHEDULE COMMAND.")
                    elif len(schedule_result) == 1 and schedule_result[0] == "NO_SLOT":
                        print(f"The client received the response from the hospital server using TCP over port {client_port}\nUnable to schedule an appointment with {command_list[1]} at this time, as all time blocks have been taken up.") 
                    elif len(schedule_result) > 1 and len(schedule_result)<9:
                        print(f"The client received the response from the hospital server using TCP over port {client_port}\nUnable to schedule an appointment with {command_list[1]} at {command_list[2]}.\nOther available time blocks are ")
                        for time_slot in schedule_result:
                            print(time_slot) 
                
                # view_appointment
                elif(len(command_list) == 1 and command_list[0] == "view_appointment"):
                    print(f"{username} sent a request to view their appointment to the Hospital Server.")
                    tcp_sock.sendall((f"VIEW_APPOINTMENT|view_appointment").encode())
                    appointment_result = tcp_sock.recv(1024).decode().strip().replace("\n", "").split(" ")
                    if(len(appointment_result) == 2):
                        print(f"The client received the response from the hospital server using TCP over port {client_port}\nYou have an appointment scheduled with {appointment_result[0]} at {appointment_result[1]}.")
                    else:
                        print(f"The client received the response from the hospital server using TCP over client port {client_port}\nYou do not have an appointment today.")
                
                # cancel
                elif(len(command_list) == 1 and command_list[0] == "cancel"):
                    print(f"{username} sent a cancellation request to the Hospital Server.")
                    tcp_sock.sendall((f"CANCEL|cancel").encode())
                    cancel_result = tcp_sock.recv(1024).decode().strip().replace("\n", "").split(" ")
                    if len(cancel_result) == 1 and cancel_result[0] == "NO_APPOINTMENT_FOUND":
                        print(f"The client received the response from the Hospital Server using TCP over port {client_port}\nYou have no appointments available to cancel.")
                    else:
                        print(f"The client received the response from the Hospital Server using TCP over port {client_port}\nYou have successfully cancelled your appointment with {cancel_result[0]} at {cancel_result[1]}.")
                
                # view_prescription
                elif(len(command_list) == 1 and command_list[0] == "view_prescription"):
                    print(f"{username} sent a request to view their prescription to the Hospital Server.")
                    tcp_sock.sendall(f"VIEW_PRESCRIPTION| {username_hash}".encode())
                    prescription_details = tcp_sock.recv(1024).decode().strip().replace("\n", "").split(" ")
                    if(len(prescription_details) == 1 and prescription_details[0] == "NO_PRESCRIPTION_RECORD_FOUND"):
                        print(f"The client received the response from the hospital server using TCP over port {client_port}\nYou do not have a prescription to look up.")
                    elif(len(prescription_details) == 3 and prescription_details[1] == "None"):
                        print(f"The client received the response from the hospital server using TCP over port {client_port}\nYou were not prescribed any treatment by {prescription_details[2]} following your diagnosis.")
                    elif(len(prescription_details) == 3):
                        print(f"The client received the response from the hospital server using TCP over port {client_port}\nYou have been prescribed {prescription_details[0]}, to be taken {prescription_details[1]}, by {prescription_details[2]}.")
                
                # help
                elif(len(command_list) == 1 and command_list[0] == "help"):
                    print(f"Please enter the command:\n<lookup>,\n<lookup <doctor>>,\n<schedule <doctor> <start_time> <illness>>,\n<cancel>,\n<view_appointment>,\n<view_prescription>,\n<quit>\n")
                    

            # doctor commands
            elif user_status == "DOCTOR":

                # view_appointments
                if(len(command_list) == 1 and command_list[0] == "view_appointments"):
                    print(f"{username} sent a request to view their scheduled appointments to the Hospital Server.")
                    tcp_sock.sendall((f"VIEW_APPOINTMENT_DR|view_appointment {username}").encode())
                    schedule_result = tcp_sock.recv(1024).decode().strip().replace("\n", "").split(" ")

                    if(len(schedule_result) == 1 and schedule_result[0] == "NO_APPOINTMENT_FOUND"):
                        print(f"The client received the response from the hospital server using TCP over port {client_port}\nYou do not have any appointments scheduled.")
                    else:
                        print(f"The client received the response from the hospital server using TCP over port {client_port}\n{username} is scheduled at times:")
                        for time_slot in schedule_result:
                            print(time_slot)
                
                # prescribe
                elif(len(command_list) == 3 and command_list[0] == "prescribe"):
                    print(f"{username} sent a request to the Hospital Server to prescribe {command_list[1]} following their diagnosis.")
                    tcp_sock.sendall((f"PRESCRIBE| {username} {sha256_hash(command_list[1])} {command_list[2]}").encode())
                    treatment, frequency = tcp_sock.recv(1024).decode().strip().replace("\n", "").split(" ")
                    print(f"The client received the response from the hospital server using TCP over port {client_port}.\nYou have successfully prescribed {command_list[1]} with {treatment}, to be taken {frequency}.")

                # view_prescription
                elif(len(command_list) == 2 and command_list[0] == "view_prescription"):
                    print(f"{username} sent a request to view {command_list[1]} prescription to the Hospital Server.")
                    payload = f"VIEW_PRESCRIPTION_DR| {username} {sha256_hash(command_list[1])}"
                    tcp_sock.sendall(payload.encode())
                    prescription_details = tcp_sock.recv(1024).decode().strip().replace("\n", "").split(" ")
                    if(len(prescription_details) == 1 and prescription_details[0] == "NO_PRESCRIPTION_RECORD_FOUND"):
                       print(f"The client received the response from the hospital server using TCP over port {client_port}\n{command_list[1]} does not have a prescription.") 
                    else:
                        print(f"The client received the response from the hospital server using TCP over port {client_port}\n{command_list[1]} has been prescribed {prescription_details[0]}, to be taken {prescription_details[1]}, by {prescription_details[2]}.")

                # help
                elif(len(command_list) == 1 and command_list[0] == "help"):
                    print(f"Please enter the command:\n<view_appointments>,\n<prescribe <patient> <frequency>>,\n<view_prescription <patient>>,\n<quit>\n")
                    
    except KeyboardInterrupt:
        tcp_sock.close()


if __name__ == "__main__":
    main()