import time
time.sleep(0.1) # Wait for USB to become ready


print("Hello, Pi Pico W!")

from HAL import *
from ClockController import *

ClockController(HAL()).run()


main.py

diagram.json

"""
# Button.py - Object-Oriented implementation of a Button
# Also added a simple implementation of a single analog Joystick
# Author: Arijit Sengupta
"""

from machine import Pin, ADC
import time
from Log import *

class Button:
    """
    A simple Button class
    Create the button using Button(pinnumber, name, handler)
    handler is typically self, and create two methods buttonPressed and buttonReleased
    to handle the push and release of the button.
    The name of the button will be passed back to the handler to identify
    which button was pressed/released
    """
    
    def __init__(self, pin, name, *, handler=None, lowActive=True):
	"""
	Initialize attributes and other internal data
	"""
	
        self._pinNo = pin
        self._name = name
        Log.i(f'Button constructor: create button {name} at pin {pin}')
        if lowActive:
            self._pin = Pin(pin, Pin.IN, Pin.PULL_UP)
        else:
            self._pin = Pin(pin, Pin.IN, Pin.PULL_DOWN)
        self._debounce_time = 0
        self._lowActive = lowActive
        self._lastStatus = None
        self._handler = None
        self.setHandler(handler)
    
    def isPressed(self):
        """ Check if the button is pressed or not - useful if polling """
        
        return (self._lowActive and self._pin.value() ==0) or (not self._lowActive and self._pin.value() == 1)
    
    def setHandler(self, handler):
        """ 
	set the handler to a new handler. Pass None to remove existing handler
	"""
        
        # if the old handler was active already, or if the new handler is None, remove the irq
        if self._handler is not None or handler is None:
            self._pin.irq(handler = None)
    
        # Now set it to th enew handler
        self._handler = handler
        # Create the IRQ if the handler is not None
        if self._handler:
            self._pin.irq(trigger = Pin.IRQ_FALLING | Pin.IRQ_RISING, handler = self._callback)
        
    def _callback(self, pin):
        """ The private interrupt handler - will call appropriate handlers """
        
        t = time.ticks_ms()
        v = self._pin.value()
        if ((self._lastStatus == None or self._lastStatus != v) and t-self._debounce_time) > 50:
            self._debounce_time=t
            self._lastStatus = v
            if self._handler is not None:
                if self.isPressed():
                    self._handler.buttonPressed(self._name)
                else:
                    self._handler.buttonReleased(self._name)
        #self._debounce_time=t

class Joystick(Button):
    """
    A joystick is technically more than a Button, but this is an example
    of using a subclass to inherit some functionality, and adding other
    functions as needed. 

    So we implement a Joystick as a subclass of a button, with the internal
    button inherited from the Button class, and the horizontal and vertical
    axes implemented as ADC pin implementations. 

    Interestingly, we may have looked into AnalogSensor as well, but there is
    no tripping of a Joystick so we don't need that.
    """
    
    # Some constants to store some basic conditions
    LOW = 0
    HIGH = 65535
    MID = 32760

    # Joystick status codes
    CENTER = 0
    UP = 1
    DOWN = 2
    LEFT = 3
    RIGHT = 4
    MOVING = 5
    
    # Status text
    statuscodes = ['Center', 'Up', 'Down', 'Left', 'Right', 'Moving']

    def __init__(self, vpin, hpin, swpin, name, *, handler=None, delta=1000):
        # Let the superclass handle all button functionality
        super().__init__(swpin, name, handler=handler, lowActive=True)
        Log.i(f'Joystick constructor: create joystick at v:{vpin}, h:{hpin}')

        # H and V axis pins must be standard ADC supporting
        if vpin <26 or vpin > 28 or hpin < 26 or hpin > 28:
            raise ValueError("Joystick Error: must connect v/h to ADC pins")

        self._v = ADC(vpin)
        self._h = ADC(hpin)
        self._delta = delta

    def getData(self):
        """
        A simple method to return the x and y values
        """

        return (self._h.read_u16(), self._v.read_u16())

    def getStatusCode(self):
        """
        Return the status code of the joystick
        0 - center, 1 left 2 right 3 up 4 down
        5 if it is not quite in any distinct position
        """

        (x,y) = self.getData()

        if x < self.LOW + self._delta:
            return self.RIGHT
        if x > self.HIGH - self._delta:
            return self.LEFT
        if y < self.LOW + self._delta:
            return self.DOWN
        if y > self.HIGH - self._delta:
            return self.UP
        if x > self.MID - self._delta and x < self.MID + self._delta and y > self.MID - self._delta and y < self.MID + self._delta:
            return self.CENTER
        return self.MOVING

    def getStatus(self):
        """
        Get the status of the joystick in text
        center, left, right, up, down, moving
        """
    
        return Joystick.statuscodes[self.getStatusCode()]


Button.py

"""
# Buzzer.py - Object-oriented implementation of active and passive buzzers
# Author: Arijit Sengupta
"""

import time
from machine import Pin, PWM
from Log import *

class Buzzer:
    """
    A simple buzzer class - use it to play and pause different sounds
    ranging from fequencies 10 through 10000
    default volume is half volume - set it between 0 and 10
    """ 
    def __init__(self, pin, name='Buzzer'):
        """
        Base class init - we don't do anything with the pin here
        """
        self._name = name
        
    def beep(self, tone=500, duration=150):
        Log.i(f"Beeping {self._name} at {tone}hz for {duration} ms")
        self.play(tone)
        time.sleep(duration / 1000)
        self.stop()
    
class ActiveBuzzer(Buzzer):
    """
    An active buzzer has an internal oscillator that plays a fixed tone when power is applied
    Cannot control the tone. Only turn on and off.
    """
    
    def __init__(self, pin, name='Buzzer'):
        super().__init__(pin, name)
        self._buz = Pin(pin, Pin.OUT)
   
    def play(self, tone=500):
        """ Play sound. Tone is ignored. """
        
        Log.i(f"Start playing {self._name}")
        self._buz.value(1)
        
    def stop(self):
        """ Stop the sound. """
        
        Log.i(f"Stop playing {self._name}")
        self._buz.value(0)
    
class PassiveBuzzer(Buzzer):
    """
    A passive buzzer does not have an internal oscillator. MC needs to send a PWM signal
    to play tones. The tone is controlled by the frequency of the PWM, and the volume level
    is controlled by the duty cycle. Setting duty cycle to 0 stops sound.
    """
    
    def __init__(self, pin, name='Buzzer'):
        Log.i("PassiveBuzzer: constructor")
        super().__init__(pin, name)
        self._buz = PWM(Pin(pin))
        self._volume = 5
        self._playing = False
        self.stop()

    def play(self, tone=500):
        """ play the supplied tone. """
        
        Log.i(f"{self._name}: playing tone {tone}")
        self._buz.freq(tone)
        self._buz.duty_u16(self._volume * 100)
        self._playing = True

    def stop(self):
        """ Stop playing sound """
        
        Log.i(f"{self._name}: stopping tone")
        self._buz.duty_u16(0)
        self._playing = False

    def setVolume(self, volume=5):
        """ Change the volume of the sound currently playing and future plays """
        
        Log.i(f"{self._name}: changing volume to {volume}")
        self._volume = volume
        if (self._playing):
            self._buz.duty_u16(self._volume * 100)


Buzzer.py

from Keypad import *

class Calculator:

    def __init__(self):
        self.acc = None
        self.operand = 0
        self.operator = None

    def setOperand(self, op):
        self.operand = op
        if self.acc == None:
            self.acc = op

    def setOperator(self, op):
        self.operator = op

    def reset(self):
        self.acc = None
        self.operand = 0
        self.operator = None

    def getResult(self):
        if self.operator == '+':
            self.acc += self.operand
        elif self.operator == '-':
            self.acc -= self.operand
        elif self.operator == '*':
            self.acc *= self.operand
        elif self.operator == '/':
            self.acc /= self.operand
        return self.acc


class CalcKeypad(Keypad):

    def __init__(self, row_pins, col_pins):
        super().__init__(row_pins, col_pins)
        self.setKeys([
            ['1','2','3','+'],
            ['4','5','6','-'],
            ['7','8','9','*'],
            ['.','0','=','/']
        ])

    def getKeyPress(self):
        k = super().scanKey()
        if k:
            if k in ['0','1','2','3','4','5','6','7','8','9','.']:
                return (k, 'num')
            elif k in ['+','-','*','/']:
                return (k, 'op')
            elif k == '=':
                return (k, 'eq')
        return None

    def decodeNumber(self, current, new)->str:
        if current == '' and new == '.':
            current = '0'
        combined = str(current) + str(new)
        try:
            f = float(combined)
            return combined
        except:
            return current


Calculator.py

"""
A basic template file for using the Model class in PicoLibrary
This will allow you to implement simple Statemodels with some basic
event-based transitions.
"""

# Import whatever Library classes you need - StateModel is obviously needed
# Counters imported for Timer functionality, Button imported for button events
import time
import random
from Log import *
from Button import *
from StateModel import *
from Calculator import *
from Displays import *

"""
This is the template for a Controller - you should rename this class to something
that is supported by your class diagram. This should associate with your other
classes, and any PicoLibrary classes. If you are using Buttons, you will implement
buttonPressed and buttonReleased.

To implement the state model, you will need to implement __init__ and 4 other methods
to support model start, stop, entry actions, exit actions, and state actions.

The following methods must be implemented:
__init__: create instances of your View and Business model classes, create an instance
of the StateModel with the necessary number of states and add the transitions, buttons
and timers that the StateModel needs

stateEntered(self, state, event) - Entry actions
stateLeft(self, state, event) - Exit actions
stateDo(self, state) - do Activities

# A couple other methods are available - but they can be left alone for most purposes

run(self) - runs the State Model - this will start at State 0 and drive the state model
stop(self) - stops the State Model - will stop processing events and stop the timers

This template currently implements a very simple state model that uses a button to
transition from state 0 to state 1 then a 5 second timer to go back to state 0.
"""

class CalculatorController:

    def __init__(self):
        
        # Instantiate whatever classes from your own model that you need to control
        # Handlers can now be set to None - we will add them to the model and it will
        # do the handling
        self.calculator = Calculator()
        keys = [
            ['1','2','3','+'],
            ['4','5','6','-'],
            ['7','8','9','*'],
            ['.','0','=','/']
        ]
        self.keypad = CalcKeypad([13,12,11,10], [9,8,7,6])
        self.keypad.setKeys(keys)
        self.currentEntry = ''
        self.lastKey = ''
        self.display = LCDDisplay()

        # Instantiate a Model. Needs to have the number of states, self as the handler
        # You can also say debug=True to see some of the transitions on the screen
        # Here is a sample for a model with 4 states
        self._model = StateModel(5, self, debug=True)
        
        # Instantiate any Buttons that you want to process events from and add
        # them to the model
        self._model.addButton(Button(22, 'c'))

        # add other buttons if needed. Note that button names must be distinct
        # for all buttons. Events will come back with [buttonname]_press and
        # [buttonname]_release
        
        # Add any timer you have. Multiple timers may be added but they must all
        # have distinct names. Events come back as [timername}_timeout

        # Add any custom events as appropriate for your state model. e.g.
        # self._model.addCustomEvent("collision_detected")

        self._model.addCustomEvent("num")
        self._model.addCustomEvent("op")
        self._model.addCustomEvent("eq")
        
        # Now add all the transitions from your state model. Any custom events
        # must be defined above first. You can have a state transition to another
        # state based on multiple events - which is why the eventlist is an array
        # Syntax: self._model.addTransition( SOURCESTATE, [eventlist], DESTSTATE)
        
        self._model.addTransition(0, ["num"], 1)

        self._model.addTransition(1, ["op"], 2)
        self._model.addTransition(1, ["eq"], 3)
        self._model.addTransition(1, ["num"], 1)
        self._model.addTransition(1, ["c_press"], 4)

        self._model.addTransition(2, ["num"], 1)
        self._model.addTransition(2, ["op"], 2)
        self._model.addTransition(2, ["eq"], 3)
        self._model.addTransition(2, ["c_press"], 0)

        self._model.addTransition(3, ["num"], 1)
        self._model.addTransition(3, ["op"], 2)
        self._model.addTransition(3, ["eq"], 3)
        self._model.addTransition(3, ["c_press"], 0)

        self._model.addTransition(4, ["no_event"], 1)
        # etc.
    
    def stateEntered(self, state, event):
        """
        stateEntered - is the handler for performing entry actions
        You get the state number of the state that just entered
        Make sure actions here are quick
        """
        
        # If statements to do whatever entry/actions you need for
        # for states that have entry actions
        Log.d(f'State {state} entered on event {event}')
        if state == 0:
            # entry actions for state 0
            self.calculator.reset()
            self.display.reset()
            self.currentEntry = ''
            self.display.showText('{:>16}'.format(0))
        elif state == 1:
            if self.lastKey:
                self.currentEntry = self.keypad.decodeNumber(self.currentEntry, self.lastKey)
                self.display.showText('{:>16}'.format(self.currentEntry))
        elif state == 2:
            if self.currentEntry:
                self.calculator.setOperand(float(self.currentEntry))
            self.calculator.setOperator(self.lastKey)
            self.display.showText(self.lastKey,1,15)
        elif state == 3:
            if self.currentEntry:
                self.calculator.setOperand(float(self.currentEntry))
            try:
                r = self.calculator.getResult()
            except:
                r = "ERROR"
            self.display.showText('{:>16}'.format(r))
        elif state == 4:
            self.display.reset()
            self.currentEntry = ''
            self.lastKey = ''
            self.display.showText('{:>16}'.format(0))            
            
    def stateLeft(self, state, event):
        """
        stateLeft - is the handler for performing exit/actions
        You get the state number of the state that just entered
        Make sure actions here are quick
        
        This is just like stateEntered, perform only exit/actions here
        """

        Log.d(f'State {state} exited on event {event}')
        if state == 2:
            # exit actions for state 0
            self.currentEntry = ''
        # etc.
    
    def stateDo(self, state):
        """
        stateDo - the method that handles the do/actions for each state
        """
        
        # Now if you want to do different things for each state that has do actions
        if state == 0:
            # State 0 do/actions
            ktuple = self.keypad.getKeyPress()
            if ktuple:
                if ktuple[1] == 'num':
                    self.lastKey = ktuple[0]
                    self._model.processEvent('num')
        elif state in [1,2,3]:
            ktuple = self.keypad.getKeyPress()
            if ktuple:
                self.lastKey = ktuple[0]
                self._model.processEvent(ktuple[1])            


    def run(self):
        """
        Create a run() method - you can call it anything you want really, but
        this is what you will need to call from main.py or someplace to start
        the state model.
        """
        
        # The run method should simply do any initializations (if needed)
        # and then call the model's run method.
        # You can send a delay as a parameter if you want something other
        # than the default 0.1s. e.g.,  self._model.run(0.25)
        self._model.run()

    def stop(self):
        # The stop method should simply do any cleanup as needed
        # and then call the model's stop method.
        # This removes the button's handlers but will need to see
        # if the IRQ handlers should also be removed
        self._model.stop()
        



CalculatorController.py

"""
First attempt and modifying the ClockController to run as a substate
under the Menu state machine.
"""

# Import whatever Library classes you need - Model is obviously needed
import time
from StateModel import *
from Buzzer import *
from Log import *
from Counters import *
from Net import *
import gc
import secrets

"""
This is the template Model Runner - you should rename this class to something
that is supported by your class diagram. This should associate with your other
classes, and any PicoLibrary classes. If you are using Buttons, you will implement
buttonPressed and buttonReleased.

To implement the model, you will need to implement 3 methods to support entry actions,
exit actions, and state actions.

This template currently implements a very simple state model that uses a button to
transition from state 0 to state 1 then a 5 second timer to go back to state 0.
"""
MAXY = 239
MAXX = 239

hx = 10
hy = 100
mx = 135
cx = 100
sz = 6
grey = 0xef9d
wk = ['Mon', 'Tue', 'Wed', 'Thu', 'Fri', 'Sat', 'Sun']
mon = ['Jan','Feb','Mar','Apr','May','Jun','Jul','Aug','Sep','Oct','Nov','Dec']

class Clock:
    def __init__(self):
        pass
            
    def updateHour(self, delta):
        t = list(Time.getTime())
        hour = t[3]
        hour = hour + delta
        if hour > 23:
            hour = 0
        elif hour < 0:
            hour = 23
        t[3] = hour
        Time.setTime(t)
        
    def updateMin(self, delta):
        t = list(Time.getTime())
        min = t[4]
        min = min + delta
        if min > 59:
            min = 0
        elif min < 0:
            min = 59
        t[4] = min
        Time.setTime(t)
        
    def showClock(self, display):
        t = Time.getTime()
        sec = t[5]%2
        if sec:
            display.showText(f'{wk[t[6]]} {mon[t[1]-1]} {t[2]:02} {t[3]:02}:{t[4]:02}', 0)
        else:
            display.showText(f'{wk[t[6]]} {mon[t[1]-1]} {t[2]:02} {t[3]:02} {t[4]:02}', 0)
            
        
    def highlightMin(self, display):
        t = Time.getTime()
        display.showText(f'{wk[t[6]]} {mon[t[1]-1]} {t[2]:02} {t[3]:02}:{t[4]:02}', 0)
        display.showText(f'Min: Y/B, Set: C',1)

    def highlightHour(self, display):
        t = Time.getTime()
        display.showText(f'{wk[t[6]]} {mon[t[1]-1]} {t[2]:02} {t[3]:02}:{t[4]:02}', 0)
        display.showText(f'Hr: Y/B,  Set: C',1)

class Stopwatch:
    """
    Stopwatch class - this class will be used to keep track of the total and
    lap times for the stopwatch.
    """
    def __init__(self):
        self.totaltime = TimeKeeper('Total')
        self.laptime = TimeKeeper('Lap')
        self.reset()

    def start(self):
        self.totaltime.start()
        self.laptime.start()

    def stop(self):
        self.totaltime.stop()
        self.laptime.stop()

    def reset(self):
        self.totaltime.reset()
        self.laptime.reset()

    def lap(self):
        self.laptime.stop()
        self.laptime.reset()
        self.laptime.start()
        
    def showStopwatch(self, display):
        """
        Show the total and lap times for the stopwatch
        """

        display.showText(f'TOT:{str(self.totaltime)}', 0)
        display.showText(f'LAP:{str(self.laptime)}', 1)

class ClockController:

    def __init__(self, hal, model=None, name=None):
        self.hal = hal
        self.clock = Clock()
        self.stopwatch = Stopwatch()
        self.name = name
        
        # TODO To convert to a subcontroller, we will need to get the model from 
        # the main controller.
        if model:
            self._model = model
        else:    
            self._model = StateModel(10,handler=self, debug=True)
            self.hal.setHandler(self._model) 
        

        # TODO then we canr remove the buttons since the super controller
        # Should have them (menu uses all buttons so yes)
        if not model:
            self._model.addButton(self.hal._buttons['W'])
            self._model.addButton(self.hal._buttons['R'])
            self._model.addButton(self.hal._buttons['Y'])
            self._model.addButton(self.hal._buttons['B'])
            self._model.addButton(self.hal._buttons['C'])
        
        # TODO The number of states in the submodel - this will be added to the
        # main model's number of states. But the number of states will
        # need to be added to the model before the transitions are added.
        # So we need to move the addTransition calls out of the constructor
        self.numstates = 10
        
        self.timer = HardwareTimer('weather')
        self._model.addTimer(self.timer)
        
        # Difference 1 - no need to instantiate any model since it should be coming
        # from the MenuController
        # MenuController will send the hal and the model to the ClockController
        # I think we may need to change the addTransition to addSubTransition or something?
        # Essentially when adding transitions to the model, state 0 should be the
        # first state assigned to the subcontroller.

        # There is no need to add any buttons here, since the MenuController has already
        # added them to the model.
        # TODO - so now we need to add the new transitions as subtransitions to the main
        # model. The main controller should do the appropriate memory management to 
        # allocate and collect the memory for the subcontroller and submodel.
        self.addSubTransitions()
        
        print("Connecting to WiFi... ", end="")
        #self.wlan = Net("FIU_WiFi", None)
        self.wlan = Net("Wokwi-GUEST", None)

        try:
            try:
                self.wlan.connect()
            except:
                print("Failed!")
                print("Connecting to Alternative... ", end="")    
                self.wlan = Net(secrets.ssid, secrets.key)
                self.wlan.connect()
        except:
            print("Failed to connect to network")
            self.wlan = None
        else:    
            ip = self.wlan.getLocalIp()
            self.hal._display.showText(ip, 1)        
            try:
                self.wlan.updateTime()
            except:
                print('Time update failed')
        
    def addSubTransitions(self):
        trans = [
            [ ('W_press',1),('R_press',1), ('C_press',6),('weather_timeout', 5)],
            [ ('Y_press',3),('B_press',3), ('W_press',2),('R_press',2), ('C_press',0)],
            [ ('Y_press',4),('B_press',4), ('W_press',1),('R_press',1), ('C_press',0)],
            [ ('no_event',1)],
            [ ('no_event',2)],
            [ ('no_event',0)],
            [ ('C_press',0), ('Y_press',7)], # first state of stopwatch
            [ ('Y_press', 8), ('C_press', 9)], # running state
            [ ('Y_press', 7), ('C_press', 6)], # stopped state
            [ ('no_event', 7)] # lap state
        ]
        if self.name:
            self._model.addSubTransitionTable(self.name, trans)
        else:
            self._model.setTransitionTable(trans)
        
    """
    Create a run() method - you can call it anything you want really, but
    this is what you will need to call from main.py or someplace to start
    the state model.
    """

    def run(self):
        # The run method should simply do any initializations (if needed)
        # and then call the model's run method.
        # You can send a delay as a parameter if you want something other
        # than the default 0.1s. e.g.,  self._model.run(0.25)
        self._model.run(0.5)

    def stop(self):
        self._model.stop()
        
    """
    stateDo - the method that handles the do/actions for each state
    """
    def stateDo(self, state):
        # Now if you want to do different things for each state you can do it:
        if state == 0:
            self.clock.showClock(self.hal._display)
        elif state == 7:
            self.stopwatch.showStopwatch(self.hal._display)
         
    """
    stateEntered - is the handler for performing entry/actions
    You get the state number of the state that just entered
    Make sure actions here are quick
    """
    def stateEntered(self, state, event):
        # Again if statements to do whatever entry/actions you need
        if state == 0:
            self.timer.start(60)
        elif state == 1:
            self.clock.highlightHour(self.hal._display)
        elif state == 2:
            self.clock.highlightMin(self.hal._display)
        elif state == 3:
            delta = -1 if event == 'B_press' else 1
            self.clock.updateHour(delta)
        elif state == 4:
            delta = -1 if event == 'B_press' else 1
            self.clock.updateMin(delta)
        elif state == 5:
            self.getWeather(self.hal._display)
        elif state == 6:
            self.stopwatch.reset()
            self.stopwatch.showStopwatch(self.hal._display)
        elif state == 7:
            if event=='Y_press':
                self.stopwatch.start()
        elif state == 8:
            self.stopwatch.stop()
        elif state == 9:
            self.stopwatch.lap()
            
    """
    stateLeft - is the handler for performing exit/actions
    You get the state number of the state that just entered
    Make sure actions here are quick
    
    This is just like stateEntered, perform only exit/actions here
    """

    def stateLeft(self, state, event):
        if state == 0:
            self.timer.cancel()
        elif state == 1 or state == 2 or state == 6:
            if event == 'C_press':
                self.hal._display.clear(1)
        # etc.
    
    def getWeather(self, d):
        apiendpoint = 'http://api.openweathermap.org/data/2.5/weather?q=Miami,Florida&units=imperial&appid=' + secrets.apikey
        d.clear(1)        
        try:
            json = self.wlan.getJson(apiendpoint)
            if json:
                temp = round(json['main']['temp'])
                humidity = round(json['main']['humidity'])
                weather = json['weather'][0]['main']
                d.showText(f'T:{temp:2} H:{humidity:2} {weather:8}',1)
        except:
            Log.e('Could not connect to endpoint')

        

ClockController.py

"""
# Counters.py
# A collection of different kinds of counters that might be used for
# various projects
# Author: Arijit Sengupta
"""

import time
from machine import Timer, RTC
from Log import *

class Counter:
    """
    Counter base class - provides an internal count, an initiailzer and a reset method
    everything else should be defined at subclass level
    """
    
    def __init__(self, name='Counter'):
        Log.i(f"{name}: constructor")
        self._name = name
        self._count = 0

    def reset(self):
        """ Reset counter memory to 0 """
        
        Log.i("Counter - reset")
        self._count = 0

class UpDownCounter(Counter):
    """ A basic updown counter - can go up or down, can set up a min and max """
    
    def __init__(self, name='Updown counter', min = None, max = None):
        Log.i(f"{name} constructor")
        super().__init__(name)
        self._min = min
        self._max = max

    def up(self, step=1):
        """
        count up - with an optional step. Note that if the result will be less than max,
        no change will be made.
        """
                
        Log.i("Updowncounter incrementing")
        if (self._max is None or self._count + step <= self._max):
            self._count = self._count + step

    def down(self, step=1):
        """
        Count down - with an optional step. Note that if the result will be less than min,
        no change will be made
        """
        
        Log.i("Updowncounter decrementing")
        if (self._min is None or self._count - step >= self._min):
            self._count = self._count - step

    def __str__(self)->str:
        """ a string representation of the internal count """
        
        return f"{self._count}"

class TimeKeeper(Counter):
    """
    Keeps time as a count. Basically a stopwatch
    Internal count stores the number of ms of counting
    Can be stopped and started many times. Only reset will set
    count to 0
    """
    
    def __init__(self,name='Timekeeper'):
        Log.i(f"{name} : constructor")
        super().__init__(name)
        self._starttime = 0
        self._running = False

    def start(self):
        """ Start the timer. Note that if previously stopped, this will add to previous time """
        
        Log.i("Timekeeper: start")
        """ If timer was already running, the start will get reset to the new time """

        self._starttime = time.ticks_ms()
        self._running = True

    def stop(self):
        """ Stop the timer. Count will save the # of ms elapsed """
        
        Log.i("Timekeeper: stop")
        """ If it was already stopped, nothing to be done """
        if self._running:
            self._running = False
            self._count = self._count + time.ticks_diff(time.ticks_ms(),self._starttime)

    def reset(self):
        """ 
        Resetting the timer will set count to 0 and starttime to the current time 
        But timer keeps running if not stopped
        """
        
        super().reset()
        self._starttime = time.ticks_ms()

    def __str__(self) -> str:
        """ Get a string representation of time in HH:MM:SS.ms format """
        
        curtime = self._count + (time.ticks_diff(time.ticks_ms(),self._starttime) if self._running else 0)
        ms = curtime % 1000
        sec = (curtime // 1000) % 60
        min = (curtime // 60000) % 60
        hr = (curtime // 3600000)
        return f"{hr:02d}:{min:02d}:{sec:02d}.{ms:03d}"


class BaseTimer(Counter):
    """ 
    Decided to create a base class for the Software and Hardware timers
    since there are many properties in common. Now allowing no handlers in init
    but obviously a handler has to be set in order to ensure something happens when
    the time runs out.
    """

    def __init__(self, name='timer', handler=None):
        super().__init__(name)
        self._handler = handler
        self._started = False

    def setHandler(self, handler):
        self._handler = handler

    def start(self, seconds):
        self._count = seconds
        self._started = True

    def cancel(self):
        self._started = False
        self._count = 0

    def reset(self):
        """ Make sure reset cancels the timer first """
        
        super().reset()
        self.cancel()
        
class HardwareTimer(BaseTimer):
    """
    This uses the hardware internal timer of the Pico. This does NOT WORK on the simulator!
    The internal count here is the timer setting that is not updated until reset or cancelled
    
    """
    
    def __init__(self, name='Hardware Timer', handler=None):
        """
        A hardware timer must be initialized with a handler. The handler must implement
        a timeout() method which will be called when the timer is up. Ideally, there
        should only be a single timer active at a time.
        """
        
        super().__init__(name, handler)
        self._timer = Timer(-1)

    def start(self, seconds):
        """ Start the timer with the number of seconds to use. """
        
        super().start(seconds)
        self._timer.init(period = int(seconds*1000), mode=Timer.ONE_SHOT, callback = self.timeout)

    def cancel(self):
        """ Cancel the timer. Note that a normal stop will cause the handler callback. """
        
        if self._started:
            self._timer.deinit()
        super().cancel()
    
    def timeout(self, timer):
        self.cancel()
        self._handler.timeout(self._name)

class SoftwareTimer(BaseTimer):
    """
    A simpler software-based timer that will work on the simulator as well. Caller
    again implements a handler method, but will need to poll the timer using the
    check method at regular intervals. Check will not return anything, but will
    call the timeout function of the caller just like the hardware timer.
    """
    
    def __init__(self, name='Software Timer', handler=None):
        super().__init__(name, handler)
        self._starttime = 0
        self._started = False

    def start(self, seconds):
        """ Start the timer with a set number of seconds """
        
        Log.i(f"Starting timer with {seconds} seconds")
        self._count = seconds
        self._starttime = time.ticks_ms()
        self._started = True

    def cancel(self):
        """ Cancel the timer - timeout hander will NOT be called """
        
        if self._started:
            self._starttime = 0
            Log.i(f"{self._count} sec timer cancelled")
        super().cancel()

    def check(self):
        """
        Periodically call the check method - can be called from anywhere
        """
        
        if self._started and time.ticks_diff(time.ticks_ms(), self._starttime) > self._count * 1000:
            Log.i(f"{self._name}: {self._count} sec timer is up")
            self._started = False
            self._count = 0
            self._handler.timeout(self._name)

class Time:
    @classmethod
    def getTime(cls):
        """
        Return the currnet time using the datetime 8-tuple:
        (year (4 dig), month (1-12), date(1-31), hour (0-23), min(0,59), sec(0-59), wkday(0-6), yday(1-366))
        """
        
        return time.localtime()

    @classmethod
    def setTime(cls, tm):
        """
        Send a semi-valid time tuple - wkday and yday are ignored
        The rest have to be valid (be careful about no. of days in a month
        """
        
        RTC().datetime((tm[0], tm[1], tm[2], 0, tm[3], tm[4], tm[5], 0))
    


Counters.py

"""
# Displays.py
# A collection of various text-based displays
# Note - as of 7/31/24 only the LCDDisplay is implemented in this module
# Use OtherDisplays.py, GraphicDisplays.py and GraphicLCD.py for the rest
# Supports LCD 1602 displays - both using an i2c backpack as well as GPIO
# Only supports number and basic text displays 
# Author: Arijit Sengupta
"""

from machine import Pin, I2C, SPI
import time
from Log import *
from gpio_lcd import *
from pico_i2c_lcd import I2cLcd

class Display:
    """
    The Display Base class - might not actually be needed
    But here to ensure we do not have a duckTyping problem
    """

    def reset(self):
        Log.e(f"reset NOT IMPLEMENTED in {type(self).__name__}")
        
    def clear(self):
        self.reset()

    def showNumber(self, number):
        Log.e(f"showNumber NOT IMPLEMENTED! in {type(self).__name__}")

    def showText(self, text):
        Log.e(f"showText NOT IMPLEMENTED! in {type(self).__name__}")

    def scroll(self, text, speed=250):
        Log.e(f"Scroll NOT IMPLEMENTED! in {type(self).__name__}")

class LCDDisplay(Display):
    """
    LCD Display class - currently supports displays with an I2C backpack
    as well as displays directly driven via the d4-d7 pins
    
    Parameters
    --------
    This is important since Python does not have method overloading, we have one init
    to do both parallel as well as i2c displays
    pass rs, e, d4, d5, d6, d7 pin numbers for parallel displays
    
    pass sda and scl for i2c displays - default is to use parallel so must pass
    both sda/scl if using i2c
    
    To connect the display to I2C 0 on GPIO pins 0,1
    usage: LCDDisplay(sda=0, scl=1)
    
    To connect the display to I2C ID 1 on GPIO pins 2,3
    usage: LCDDisplay(sda=2, scl=3)
    
    To connect via parallel with rs on pin 5, e on pin 4
    and d4,d5,d6,d7 to pins 3,2,1 and 0:
    usage:  LCDDisplay()  # yeah those are the default so you don't need to send
    usage: LCDDisplay(rs=5, e=4, d4=3, d5=2, d6=1, d7=0) # preferred - you can see how its hooked up
    
    """
    
    def __init__(self, rs=5, e=4, d4=3, d5=2, d6=1, d7=0, *, sda=-1, scl=-1):
        """
        Combined constructor for the direct-driven displays
        explicitly pass in the sda and scl if you need to use I2C
        """
        
        if sda < 0:
            Log.i("LCDDisplay Constructor")
            self._lcd = GpioLcd(rs_pin=Pin(rs),
                enable_pin=Pin(e),
                d4_pin=Pin(d4),
                d5_pin=Pin(d5),
                d6_pin=Pin(d6),
                d7_pin=Pin(d7),
                num_lines=2, num_columns=16)
        else:
            Log.i("LCDDisplay (I2C) Constructor")
            """
            Lets determine the i2c id from the sda and scl pins
            """
            i2cid = -1 # lets set an invalid value to start with
            if (sda == 0 and scl == 1) or (sda == 4 and scl == 5) or (sda == 8 and scl == 9) or (sda == 12 and scl == 13) or (sda == 16 and scl == 17) or (sda == 20 and scl == 21):    
                i2cid = 0
            elif (sda == 2 and scl == 3) or (sda == 6 and scl == 7) or (sda == 10 and scl == 11) or (sda == 14 and scl == 15) or (sda == 18 and scl == 19) or (sda == 26 and scl == 27):
                i2cid = 1
            else:
                raise ValueError('Invalid SDA/SCL pins')
            i2c = I2C(i2cid, sda=Pin(sda), scl=Pin(scl), freq=400000)
            try:
                I2C_ADDR = i2c.scan()[0]
                self._lcd = I2cLcd(i2c, I2C_ADDR, 2, 16)
            except:
                raise ValueError('Could not connect to display - check wiring.')
        self._working = False

    def reset(self):
        """ 
        clear the display screen
        """
        
        Log.i("LCDDisplay: reset")
        self._lcd.clear()
        self._working = False

    def clear(self, line=-1):
        """
        Clear only a single line - negative to reset
        """

        if line < 0 or line > 1:
            self.reset()
        else:
            self.showText(f'{" "*16}',line)

    def showNumber(self, number, row=0, col=0):
        """
        show a single number
        """
        
        if self._working:
            Log.e("LCDDisplay - Display busy")
            return
        self._working = True
        Log.i(f"LCDDisplay - showing number {number} at {row},{col}")
        self._lcd.move_to(col, row)
        self._lcd.putstr(f"{number}")
        self._working = False

    def showNumbers(self, num1, num2, colon=True, row=0, col=0):
        """
        Show two numbers optionally separated by a colon
        by default, the colon is shown
        """
        
        if self._working:
            Log.e("LCDDisplay - Display busy")
            return
        self._working = True
        Log.i(f"LCDDisplay - showing numbers {num1}, {num2} at {row},{col}")
        self._lcd.move_to(col, row)
        colsym = ":" if colon else " "
        self._lcd.putstr(f"{num1}{colsym}{num2}")
        self._working = False

    def showText(self, text, row=0, col=0):
        """
        Show a string - only first 4 characters will be shown
        for anything bigger than 4 characters.
        """
        
        if self._working:
            Log.e("LCDDisplay - Display busy")
            return
        self._working = True
        Log.i(f"LCDDisplay - showing text {text} at {row},{col}")
        self._lcd.move_to(col, row)
        self._lcd.putstr(text)
        self._working = False

    def addShape(self, position, shapearray):
        """
        Add a custom character at a position.
        position must be between 0 and 7
        shapearray needs to be a bytearray that can
        be created by going to
        https://maxpromer.github.io/LCD-Character-Creator/
        and then copying the bytes into a bytearray as a list of hex values
        as in the example below:

        d.addShape(1, [0x00,0x0A,0x0A,0x00,0x11,0x0E,0x04,0x00]) # a smiley face
        d.showText(chr(1), 0,5) # show the smiley face at position 5 of row 0
        """
        
        if position < 0 or position > 7:
            raise ValueError('Position must be between 0 and 7.')
        if len(shapearray) != 8:
            raise ValueError('Make sure array is exactly 8 bytes')
        self._lcd.custom_char(position, shapearray)

    def scroll(self, text, row=0, speed=100, skip=2):
        """
        A very simple scroll implementation
        Scrolls some text right to left in a row

        speed is essentially the delay between refresh - lower the better
        skip is the number of chars to skip for the next refresh
        higher number will be faster but may be jerky. lower will be smooth
        but slower.

        I2C devices may not have best scrolling performance. Works
        better with GPIO-driven displays
        """

        if self._working:
            Log.e("LCDDisplay - Display busy")
            return
        self._working = True
        Log.i(f"LCDDisplay - scrolling text {text} in row {row}")
        for p in range(0,len(text)+skip, skip):
            curst = (text+' '*(16+skip))[p:p+16]
            for c in range(16,0,-1):
                self._lcd.move_to(c-1, row)
                self._lcd.putchar(curst[c-1])
            time.sleep(speed/1000)
        self._working = False


Displays.py

"""Source: Instructables, Tom's Hardware and GitHub """
"""Not Authored by Dr. Sengupta """
"""Implements a HD44780 character LCD connected via ESP32/RPi GPIO pins."""

from lcd_api import LcdApi
from machine import Pin
from utime import sleep_ms, sleep_us


class GpioLcd(LcdApi):
    """Implements a HD44780 character LCD connected via ESP32 GPIO pins."""

    def __init__(self, rs_pin, enable_pin, d0_pin=None, d1_pin=None,
                 d2_pin=None, d3_pin=None, d4_pin=None, d5_pin=None,
                 d6_pin=None, d7_pin=None, rw_pin=None, backlight_pin=None,
                 num_lines=2, num_columns=16):
        """Constructs the GpioLcd object. All of the arguments must be machine.Pin
        objects which describe which pin the given line from the LCD is
        connected to.
        When used in 4-bit mode, only D4, D5, D6, and D7 are physically
        connected to the LCD panel. This function allows you call it like
        GpioLcd(rs, enable, D4, D5, D6, D7) and it will interpret that as
        if you had actually called:
        GpioLcd(rs, enable, d4=D4, d5=D5, d6=D6, d7=D7)
        The enable 8-bit mode, you need pass d0 through d7.
        The rw pin isn't used by this library, but if you specify it, then
        it will be set low.
        """
        self.rs_pin = rs_pin
        self.enable_pin = enable_pin
        self.rw_pin = rw_pin
        self.backlight_pin = backlight_pin
        self._4bit = True
        if d4_pin and d5_pin and d6_pin and d7_pin:
            self.d0_pin = d0_pin
            self.d1_pin = d1_pin
            self.d2_pin = d2_pin
            self.d3_pin = d3_pin
            self.d4_pin = d4_pin
            self.d5_pin = d5_pin
            self.d6_pin = d6_pin
            self.d7_pin = d7_pin
            if self.d0_pin and self.d1_pin and self.d2_pin and self.d3_pin:
                self._4bit = False
        else:
            # This is really 4-bit mode, and the 4 data pins were just
            # passed as the first 4 arguments, so we switch things around.
            self.d0_pin = None
            self.d1_pin = None
            self.d2_pin = None
            self.d3_pin = None
            self.d4_pin = d0_pin
            self.d5_pin = d1_pin
            self.d6_pin = d2_pin
            self.d7_pin = d3_pin
        self.rs_pin.init(Pin.OUT)
        self.rs_pin.value(0)
        if self.rw_pin:
            self.rw_pin.init(Pin.OUT)
            self.rw_pin.value(0)
        self.enable_pin.init(Pin.OUT)
        self.enable_pin.value(0)
        self.d4_pin.init(Pin.OUT)
        self.d5_pin.init(Pin.OUT)
        self.d6_pin.init(Pin.OUT)
        self.d7_pin.init(Pin.OUT)
        self.d4_pin.value(0)
        self.d5_pin.value(0)
        self.d6_pin.value(0)
        self.d7_pin.value(0)
        if not self._4bit:
            self.d0_pin.init(Pin.OUT)
            self.d1_pin.init(Pin.OUT)
            self.d2_pin.init(Pin.OUT)
            self.d3_pin.init(Pin.OUT)
            self.d0_pin.value(0)
            self.d1_pin.value(0)
            self.d2_pin.value(0)
            self.d3_pin.value(0)
        if self.backlight_pin is not None:
            self.backlight_pin.init(Pin.OUT)
            self.backlight_pin.value(0)

        # See about splitting this into begin

        sleep_ms(20)   # Allow LCD time to powerup
        # Send reset 3 times
        self.hal_write_init_nibble(self.LCD_FUNCTION_RESET)
        sleep_ms(5)    # need to delay at least 4.1 msec
        self.hal_write_init_nibble(self.LCD_FUNCTION_RESET)
        sleep_ms(1)
        self.hal_write_init_nibble(self.LCD_FUNCTION_RESET)
        sleep_ms(1)
        cmd = self.LCD_FUNCTION
        if not self._4bit:
            cmd |= self.LCD_FUNCTION_8BIT
        self.hal_write_init_nibble(cmd)
        sleep_ms(1)
        LcdApi.__init__(self, num_lines, num_columns)
        if num_lines > 1:
            cmd |= self.LCD_FUNCTION_2LINES
        self.hal_write_command(cmd)

    def hal_pulse_enable(self):
        """Pulse the enable line high, and then low again."""
        self.enable_pin.value(0)
        sleep_us(1)
        self.enable_pin.value(1)
        sleep_us(1)       # Enable pulse needs to be > 450 nsec
        self.enable_pin.value(0)
        sleep_us(100)     # Commands need > 37us to settle

    def hal_write_init_nibble(self, nibble):
        """Writes an initialization nibble to the LCD.
        This particular function is only used during initialization.
        """
        self.hal_write_4bits(nibble >> 4)

    def hal_backlight_on(self):
        """Allows the hal layer to turn the backlight on."""
        if self.backlight_pin:
            self.backlight_pin.value(1)

    def hal_backlight_off(self):
        """Allows the hal layer to turn the backlight off."""
        if self.backlight_pin:
            self.backlight_pin.value(0)

    def hal_write_command(self, cmd):
        """Writes a command to the LCD.
        Data is latched on the falling edge of E.
        """
        self.rs_pin.value(0)
        self.hal_write_8bits(cmd)
        if cmd <= 3:
            # The home and clear commands require a worst
            # case delay of 4.1 msec
            sleep_ms(5)

    def hal_write_data(self, data):
        """Write data to the LCD."""
        self.rs_pin.value(1)
        self.hal_write_8bits(data)

    def hal_write_8bits(self, value):
        """Writes 8 bits of data to the LCD."""
        if self.rw_pin:
            self.rw_pin.value(0)
        if self._4bit:
            self.hal_write_4bits(value >> 4)
            self.hal_write_4bits(value)
        else:
            self.d3_pin.value(value & 0x08)
            self.d2_pin.value(value & 0x04)
            self.d1_pin.value(value & 0x02)
            self.d0_pin.value(value & 0x01)
            self.hal_write_4bits(value >> 4)

    def hal_write_4bits(self, nibble):
        """Writes 4 bits of data to the LCD."""
        self.d7_pin.value(nibble & 0x08)
        self.d6_pin.value(nibble & 0x04)
        self.d5_pin.value(nibble & 0x02)
        self.d4_pin.value(nibble & 0x01)
        self.hal_pulse_enable()

gpio_lcd.py

"""
The HAL will take care of aggregating all hardware that any controller can use so we can have
a single HAL instance shared across all models. The HAL can have the handler for any event
processing back to the controller. The controller can then decide what to do with the event.
"""

# Import whatever Library classes you need - Model is obviously needed
import time
from Button import *
from Buzzer import *
from Log import *
from Displays import *
from Sensors import *
from Calculator import *
import gc


"""
This is the template Model Runner - you should rename this class to something
that is supported by your class diagram. This should associate with your other
classes, and any PicoLibrary classes. If you are using Buttons, you will implement
buttonPressed and buttonReleased.

To implement the model, you will need to implement 3 methods to support entry actions,
exit actions, and state actions.

This template currently implements a very simple state model that uses a button to
transition from state 0 to state 1 then a 5 second timer to go back to state 0.
"""

class HAL:

    def __init__(self, handler=None):
        
        # Instantiate whatever classes from your own model that you need to control
        # Handlers can now be set to None - we will add them to the model and it will
        # do the handling
        self._buttons = {
            'C': Button(18, "C", handler=self),
            'W': Button(19, "W", handler=self),
            'R': Button(20, "R", handler=self),
            'Y': Button(21, "Y", handler=self),
            'B': Button(22, "B", handler=self)}

        self._buzzer = PassiveBuzzer(17, 'Buzzer')
        keys = [
            ['1','2','3','+'],
            ['4','5','6','-'],
            ['7','8','9','*'],
            ['.','0','=','/']
        ]
        self.keypad = CalcKeypad([13,12,11,10], [9,8,7,6])
        self.keypad.setKeys(keys)

        gc.enable()
        gc.collect()
        self._display = LCDDisplay()
        self._display.clear()
        self.handler = handler
    
    def buttonPressed(self, name):
        if self.handler is not None:
            self.handler.buttonPressed(name)

    def buttonReleased(self, name):
        if self.handler is not None:
            self.handler.buttonReleased(name)

    def setHandler(self, handler):
        self.handler = handler

HAL.py

"""
Keypad.py - a simple implementation of a mxn keypad
typically used for providing input to microcontrollers

This is a fairly simple implementation and does use
a blocking scan, so cannot use this for detecting multi-presses

# Author: Arijit Sengupta
"""
from machine import Pin
import utime

default_keys = [
    ['1','2','3','A'],
    ['4','5','6','B'],
    ['7','8','9','C'],
    ['*','0','#','D']
]

class Keypad:
    """
    Keypad is a mxn matrix - read by turning the rows into 
    outputs and columns into inputs. Read by setting each row
    high one at a time, then checking which column became high
    and returning the value at the column.

    These come in many sizes, so keeping it at least somewhat
    flexible to support keypads of different types, but
    defaulting to the standard hex keypads that are most
    commonly available.
    """

    def __init__(self, row_pins, col_pins):
        """
        Initialize the keypad - send in the pin numbers that
        connect the rows and pin numbers that connect the columns
        """
        self._lastscan = 0
        self._rows = len(row_pins)
        self._cols = len(col_pins)

        self._row_pins = [None] * self._rows
        self._col_pins = [None] * self._cols
        self._keys = default_keys

        for r in range(0, self._rows):
            self._row_pins[r] = Pin(row_pins[r], Pin.OUT)

        for c in range(0, self._cols):
            self._col_pins[c] = Pin(col_pins[c], Pin.IN, Pin.PULL_DOWN)

    def setKeys(self, keys = default_keys):
        """
        Set the keys if they are not the default
        hex keypad
        """

        self._keys = keys

    def scanKey(self,delay=250)->str:
        """
        Scan the keypad once and return if anything is detected
        to be pressed. returns None if nothing is pressed.
        
        To avoid multi-presses, if a request comes from scanKey within
        delay ms of the last valid scan, we are going to return None
        """
        if utime.ticks_ms()-self._lastscan < delay:
            return None
        for rowKey in range(self._rows):
            self._row_pins[rowKey].value(1)
            for colKey in range(self._cols):
                if self._col_pins[colKey].value() == 1:
                    key = self._keys[rowKey][colKey]
                    self._row_pins[rowKey].value(0)
                    self._lastscan = utime.ticks_ms()
                    return(key)
            self._row_pins[rowKey].value(0)
        return None

        

Keypad.py

"""Source: Instructables, Tom's Hardware and GitHub """
"""Not Authored by Dr. Sengupta """
"""Provides an API for talking to HD44780 compatible character LCDs."""

import time

class LcdApi:
    """Implements the API for talking with HD44780 compatible character LCDs.
    This class only knows what commands to send to the LCD, and not how to get
    them to the LCD.
    It is expected that a derived class will implement the hal_xxx functions.
    """

    # The following constant names were lifted from the avrlib lcd.h
    # header file, however, I changed the definitions from bit numbers
    # to bit masks.
    #
    # HD44780 LCD controller command set

    LCD_CLR = 0x01              # DB0: clear display
    LCD_HOME = 0x02             # DB1: return to home position

    LCD_ENTRY_MODE = 0x04       # DB2: set entry mode
    LCD_ENTRY_INC = 0x02        # --DB1: increment
    LCD_ENTRY_SHIFT = 0x01      # --DB0: shift

    LCD_ON_CTRL = 0x08          # DB3: turn lcd/cursor on
    LCD_ON_DISPLAY = 0x04       # --DB2: turn display on
    LCD_ON_CURSOR = 0x02        # --DB1: turn cursor on
    LCD_ON_BLINK = 0x01         # --DB0: blinking cursor

    LCD_MOVE = 0x10             # DB4: move cursor/display
    LCD_MOVE_DISP = 0x08        # --DB3: move display (0-> move cursor)
    LCD_MOVE_RIGHT = 0x04       # --DB2: move right (0-> left)

    LCD_FUNCTION = 0x20         # DB5: function set
    LCD_FUNCTION_8BIT = 0x10    # --DB4: set 8BIT mode (0->4BIT mode)
    LCD_FUNCTION_2LINES = 0x08  # --DB3: two lines (0->one line)
    LCD_FUNCTION_10DOTS = 0x04  # --DB2: 5x10 font (0->5x7 font)
    LCD_FUNCTION_RESET = 0x30   # See "Initializing by Instruction" section

    LCD_CGRAM = 0x40            # DB6: set CG RAM address
    LCD_DDRAM = 0x80            # DB7: set DD RAM address

    LCD_RS_CMD = 0
    LCD_RS_DATA = 1

    LCD_RW_WRITE = 0
    LCD_RW_READ = 1

    def __init__(self, num_lines, num_columns):
        self.num_lines = num_lines
        if self.num_lines > 4:
            self.num_lines = 4
        self.num_columns = num_columns
        if self.num_columns > 40:
            self.num_columns = 40
        self.cursor_x = 0
        self.cursor_y = 0
        self.implied_newline = False
        self.backlight = True
        self.display_off()
        self.backlight_on()
        self.clear()
        self.hal_write_command(self.LCD_ENTRY_MODE | self.LCD_ENTRY_INC)
        self.hide_cursor()
        self.display_on()

    def clear(self):
        """Clears the LCD display and moves the cursor to the top left
        corner.
        """
        self.hal_write_command(self.LCD_CLR)
        self.hal_write_command(self.LCD_HOME)
        self.cursor_x = 0
        self.cursor_y = 0

    def show_cursor(self):
        """Causes the cursor to be made visible."""
        self.hal_write_command(self.LCD_ON_CTRL | self.LCD_ON_DISPLAY |
                               self.LCD_ON_CURSOR)

    def hide_cursor(self):
        """Causes the cursor to be hidden."""
        self.hal_write_command(self.LCD_ON_CTRL | self.LCD_ON_DISPLAY)

    def blink_cursor_on(self):
        """Turns on the cursor, and makes it blink."""
        self.hal_write_command(self.LCD_ON_CTRL | self.LCD_ON_DISPLAY |
                               self.LCD_ON_CURSOR | self.LCD_ON_BLINK)

    def blink_cursor_off(self):
        """Turns on the cursor, and makes it no blink (i.e. be solid)."""
        self.hal_write_command(self.LCD_ON_CTRL | self.LCD_ON_DISPLAY |
                               self.LCD_ON_CURSOR)

    def display_on(self):
        """Turns on (i.e. unblanks) the LCD."""
        self.hal_write_command(self.LCD_ON_CTRL | self.LCD_ON_DISPLAY)

    def display_off(self):
        """Turns off (i.e. blanks) the LCD."""
        self.hal_write_command(self.LCD_ON_CTRL)

    def backlight_on(self):
        """Turns the backlight on.
        This isn't really an LCD command, but some modules have backlight
        controls, so this allows the hal to pass through the command.
        """
        self.backlight = True
        self.hal_backlight_on()

    def backlight_off(self):
        """Turns the backlight off.
        This isn't really an LCD command, but some modules have backlight
        controls, so this allows the hal to pass through the command.
        """
        self.backlight = False
        self.hal_backlight_off()

    def move_to(self, cursor_x, cursor_y):
        """Moves the cursor position to the indicated position. The cursor
        position is zero based (i.e. cursor_x == 0 indicates first column).
        """
        self.cursor_x = cursor_x
        self.cursor_y = cursor_y
        addr = cursor_x & 0x3f
        if cursor_y & 1:
            addr += 0x40    # Lines 1 & 3 add 0x40
        if cursor_y & 2:    # Lines 2 & 3 add number of columns
            addr += self.num_columns
        self.hal_write_command(self.LCD_DDRAM | addr)

    def putchar(self, char):
        """Writes the indicated character to the LCD at the current cursor
        position, and advances the cursor by one position.
        """
        if char == '\n':
            if self.implied_newline:
                # self.implied_newline means we advanced due to a wraparound,
                # so if we get a newline right after that we ignore it.
                pass
            else:
                self.cursor_x = self.num_columns
        else:
            self.hal_write_data(ord(char))
            self.cursor_x += 1
        if self.cursor_x >= self.num_columns:
            self.cursor_x = 0
            self.cursor_y += 1
            self.implied_newline = (char != '\n')
        if self.cursor_y >= self.num_lines:
            self.cursor_y = 0
        self.move_to(self.cursor_x, self.cursor_y)

    def putstr(self, string):
        """Write the indicated string to the LCD at the current cursor
        position and advances the cursor position appropriately.
        """
        for char in string:
            self.putchar(char)

    def custom_char(self, location, charmap):
        """Write a character to one of the 8 CGRAM locations, available
        as chr(0) through chr(7).
        """
        location &= 0x7
        self.hal_write_command(self.LCD_CGRAM | (location << 3))
        self.hal_sleep_us(40)
        for i in range(8):
            self.hal_write_data(charmap[i])
            self.hal_sleep_us(40)
        self.move_to(self.cursor_x, self.cursor_y)

    def hal_backlight_on(self):
        """Allows the hal layer to turn the backlight on.
        If desired, a derived HAL class will implement this function.
        """
        pass

    def hal_backlight_off(self):
        """Allows the hal layer to turn the backlight off.
        If desired, a derived HAL class will implement this function.
        """
        pass

    def hal_write_command(self, cmd):
        """Write a command to the LCD.
        It is expected that a derived HAL class will implement this
        function.
        """
        raise NotImplementedError

    def hal_write_data(self, data):
        """Write data to the LCD.
        It is expected that a derived HAL class will implement this
        function.
        """
        raise NotImplementedError

    def hal_sleep_us(self, usecs):
        """Sleep for some time (given in microseconds)."""
        time.sleep_us(usecs)

lcd_api.py

"""
Log.py - a simplistic Logging process. Built to kind of mimic the
Android Logging process, but at the same time having a global level
set to see the types of logs being displayed.

Basic usage:

Log.level = DEBUG  # set global log level

# Options are: ALL/INFO (everything) DEBUG (debug and higher), ERRO (only errors)
Log.i(f'help')     # Info message: f-strings recommended for showing variables
Log.d(f'value: {v}') # Debug message
Log.e(f'Exception: {x}') # Error message
Log.name('Myproject') # Set a global project name
"""

""" Debug levels """
ALL = 4  # All messages are displayed
INFO = 3  # Basically the same as ALL - for future-proofing
DEBUG = 2  # Info is hidden - debug and higher shown
ERROR = 1  # Only error messages shown
NONE = 0  # No messages are shown from log classes


class Log:

    name = ''
    level = ALL

    @classmethod
    def i(cls, message):
        if (cls.level >= INFO):
            Log.pr(message)

    @classmethod
    def d(cls, message):
        if (cls.level >= DEBUG):
            Log.pr(message)

    @classmethod
    def e(cls, message):
        if (cls.level >= ERROR):
            Log.pr(message)

    @classmethod
    def pr(cls, message):
        if cls.name:
            m = cls.name + ": " + message
        else:
            m = message
        print(m)


if __name__ == '__main__':
    print("Hello")
    Log.level = ALL
    Log.name = 'Test'
    Log.i(f'This should print (level: {Log.level})')
    
    Log.level = ERROR
    Log.i(f'This should NOT print (level: {Log.level})')
    Log.e(f'This should print (level: {Log.level})')
    



Log.py

"""
Net.py - a simple implementation of a Network class in Micropython
Adapted by Arijit Sengupta from Adafruit/StackOverflow

This is not thoroughly tested - use at your own risk
"""

import time
import network
import urequests as requests
import ubinascii
from Log import *

class Net:
    
    def __init__(self, ssid, password):
        """
        Initialize wifi access point with an ssid and password
        Note that empty passwords are accepted so you can connect to secure
        networks with an empty password ""
        For unsecured networks, use None for password
        """
        
        self._ssid = ssid
        self._password = password
        self._wlan = None
        self._blink = False
        self._wlan = network.WLAN(network.STA_IF)
        
    def connect(self, max_wait=10):
        """
        Connect to the wifi network with a maximum wait time
        """
        
        self._wlan.active(True)
        if self._password != None:
            self._wlan.connect(self._ssid, self._password)
        else:
            self._wlan.connect(self._ssid, security=0)

        # Wait for connection to establish
        Log.i(f'Net: connecting to {self._ssid}')
        print('waiting for connection...', end="")
        while max_wait > 0:
            if self._wlan.status() < 0 or self._wlan.status() >= 3:
                    break
            max_wait -= 1
            print('.', end="")
            time.sleep(1)
            
        # Manage connection errors
        if self._wlan.status() != 3:
            raise RuntimeError('Network Connection has failed!')
        else:
            print("Connected!")
            Log.i('Net: connected!')
    
    def disconnect(self):
        """ Disconnect from wifi network """
        
        self._wlan.disconnect()
        self._wlan.active(False)
        
    
    def getLocalIp(self):
        """ Get the local IP address as a string """

        if self._wlan.active():
            info = self._wlan.ifconfig()
            return info[0]
        else:
            return 'Not connected'
        
    def getMac(self):
        """ Get the MAC address of the interface """
        
        mac = ubinascii.hexlify(self._wlan.config('mac'),':').decode()
        return mac
        
    def updateTime(self, timezone = 'America/New_York'):
        """ Update local time using an the world timeapi """
        
        apiendpoint = 'http://worldtimeapi.org/api/timezone/' + timezone
        json = self.getJson(apiendpoint)
        if json:
            unixtime = json['unixtime']
            raw_offset = json['raw_offset']
            dst_offset = json['dst_offset']
            unixtime = unixtime + raw_offset + dst_offset
            import machine
            tm = time.gmtime(unixtime)
            machine.RTC().datetime((tm[0], tm[1], tm[2], tm[6] + 1, tm[3], tm[4], tm[5], 0))
        return time.localtime()

    def getFormattedTime(self, extra='day'):
        """
        Get the local time as a String that fits a 16 char line
        If shorter strings are desired, just use time.localtime and format as needed

        extra can be one of 'day' (shows weekday)
                            'year' shows the year
                            'sec' shows seconds
        Unfortunately only one extra can be chosen
        """
        
        wk = ['Mon', 'Tue', 'Wed', 'Thu', 'Fri', 'Sat', 'Sun']
        mon = ['Jan','Feb','Mar','Apr','May','Jun','Jul','Aug','Sep','Oct','Nov','Dec']
        (yy, mm, dd, h, m, s, w, y) = time.localtime()
        self._blink = not self._blink
        col = ':' if self._blink else ' '
        if extra == 'sec':
            return f'{mon[mm-1]}-{dd:02} {h:02}:{m:02}:{s:02}'
        elif extra == 'day':
            return f'{wk[w]} {mon[mm-1]} {dd:02} {h:02}{col}{m:02}'
        else:
            return f'{mm:02}/{dd:02}/{yy:04} {h:02}{col}{m:02}'

    def getJson(self, url):
        """
        Get the JSON data from a REST API. Only valid JSON supported.
        Only GET for now. No POST or PUT. Returns the parsed json structure
        """
        
        try:
            if self._wlan == None:
                self.connect()
            data=requests.get(url)
            jsondata = data.json()
            data.close()
            return jsondata
        except:
            Log.e("could not connect (status =" + str(self._wlan.status()) + ")")
            return None



Net.py

"""Source: Instructables, Tom's Hardware and GitHub """
"""Not Authored by Dr. Sengupta """

import utime
import gc

from lcd_api import LcdApi
from machine import I2C

# PCF8574 pin definitions
MASK_RS = 0x01       # P0
MASK_RW = 0x02       # P1
MASK_E  = 0x04       # P2

SHIFT_BACKLIGHT = 3  # P3
SHIFT_DATA      = 4  # P4-P7

class I2cLcd(LcdApi):
    
    #Implements a HD44780 character LCD connected via PCF8574 on I2C

    def __init__(self, i2c, i2c_addr, num_lines, num_columns):
        self.i2c = i2c
        self.i2c_addr = i2c_addr
        self.i2c.writeto(self.i2c_addr, bytes([0]))
        utime.sleep_ms(20)   # Allow LCD time to powerup
        # Send reset 3 times
        self.hal_write_init_nibble(self.LCD_FUNCTION_RESET)
        utime.sleep_ms(5)    # Need to delay at least 4.1 msec
        self.hal_write_init_nibble(self.LCD_FUNCTION_RESET)
        utime.sleep_ms(1)
        self.hal_write_init_nibble(self.LCD_FUNCTION_RESET)
        utime.sleep_ms(1)
        # Put LCD into 4-bit mode
        self.hal_write_init_nibble(self.LCD_FUNCTION)
        utime.sleep_ms(1)
        LcdApi.__init__(self, num_lines, num_columns)
        cmd = self.LCD_FUNCTION
        if num_lines > 1:
            cmd |= self.LCD_FUNCTION_2LINES
        self.hal_write_command(cmd)
        gc.collect()

    def hal_write_init_nibble(self, nibble):
        # Writes an initialization nibble to the LCD.
        # This particular function is only used during initialization.
        byte = ((nibble >> 4) & 0x0f) << SHIFT_DATA
        self.i2c.writeto(self.i2c_addr, bytes([byte | MASK_E]))
        self.i2c.writeto(self.i2c_addr, bytes([byte]))
        gc.collect()
        
    def hal_backlight_on(self):
        # Allows the hal layer to turn the backlight on
        self.i2c.writeto(self.i2c_addr, bytes([1 << SHIFT_BACKLIGHT]))
        gc.collect()
        
    def hal_backlight_off(self):
        #Allows the hal layer to turn the backlight off
        self.i2c.writeto(self.i2c_addr, bytes([0]))
        gc.collect()
        
    def hal_write_command(self, cmd):
        # Write a command to the LCD. Data is latched on the falling edge of E.
        byte = ((self.backlight << SHIFT_BACKLIGHT) |
                (((cmd >> 4) & 0x0f) << SHIFT_DATA))
        self.i2c.writeto(self.i2c_addr, bytes([byte | MASK_E]))
        self.i2c.writeto(self.i2c_addr, bytes([byte]))
        byte = ((self.backlight << SHIFT_BACKLIGHT) |
                ((cmd & 0x0f) << SHIFT_DATA))
        self.i2c.writeto(self.i2c_addr, bytes([byte | MASK_E]))
        self.i2c.writeto(self.i2c_addr, bytes([byte]))
        if cmd <= 3:
            # The home and clear commands require a worst case delay of 4.1 msec
            utime.sleep_ms(5)
        gc.collect()

    def hal_write_data(self, data):
        # Write data to the LCD. Data is latched on the falling edge of E.
        byte = (MASK_RS |
                (self.backlight << SHIFT_BACKLIGHT) |
                (((data >> 4) & 0x0f) << SHIFT_DATA))
        self.i2c.writeto(self.i2c_addr, bytes([byte | MASK_E]))
        self.i2c.writeto(self.i2c_addr, bytes([byte]))
        byte = (MASK_RS |
                (self.backlight << SHIFT_BACKLIGHT) |
                ((data & 0x0f) << SHIFT_DATA))      
        self.i2c.writeto(self.i2c_addr, bytes([byte | MASK_E]))
        self.i2c.writeto(self.i2c_addr, bytes([byte]))
        gc.collect()

pico_i2c_lcd.py

"""
# Sensors.py
# A simple Sensor hierarchy for digital and analog sensors
# Added support for Ultrasonic Sensor on 9/11/23
# Added support for DHT11/DHT22 sensor on 6/14/24
# Author: Arijit Sengupta
"""

from machine import Pin, ADC
import utime
import math
import dht
from Log import *

class Sensor:
    """
    The top level sensor class - assume each sensor uses 
    at least one pin. We do not create the IO here because
    some sensors may use Analog inputs
    
    Parameters
    --------
    pin: pin number where the sensor is connected
    lowActive: set to True if the sensor gets low (or under threshold)
    when tripped. So an analog light sensor should normally get a high
    value but when covered, go low. So lowActive should be True
    
    A force sensor would be opposite - tripped when force gets high
    so lowActive should be False
    """
    
    def __init__(self, pin, name='Sensor', lowActive = True):
        self._pin = pin
        self._lowActive = lowActive
        self._name = name
        
    def tripped(self)->bool:
        Log.e(f"tripped not implemented for {type(self).__name__} {self._name}")
        return False

class DigitalSensor(Sensor):
    """
    A simple digital sensor (like the commonly available LC-393 that is a light sensor)
    has a digital output that flips based on a manual threshold control

    We are just going to poll this to keep things simple
    """
    
    def __init__(self, pin, name='Digital Sensor', lowActive=True):
        super().__init__(pin, name, lowActive)
        self._pinio = Pin(self._pin, Pin.IN)

    def tripped(self)->bool:
        v = self._pinio.value()
        if (self._lowActive and v == 0) or (not self._lowActive and v == 1):
            Log.i(f"DigitalSensor {self._name}: sensor tripped")
            return True
        else:
            return False
        
class TiltSensor(DigitalSensor):
    """
    A tilt sensor looks like a cap but has just a metal ball on two contacts
    when you tilt, the ball rolls off and the contact opens. That way its very
    much like a button which is always pressed.
    """
    
    def __init__(self, pin, name='Tilt Sensor'):
        # Init - do not call the super init - just create the Pin.
        super().__init__(pin, name)
        self._pinio = Pin(pin, Pin.IN, Pin.PULL_UP)
        
    def tripped(self):
        if self._pinio.value() == 1:
            Log.i(f"TiltSensor {self._name}: sensor tripped")
            return True
        else:
            return False

class AnalogSensor(Sensor):
    """
    A simple analog sensor that returns a voltage or voltage ratio output
    that can be read in using an ADC. Pico reads in via a 16bit unsigned

    We are just going to poll this to keep things simple
    """
    
    def __init__(self, pin, name='Analog Sensor', lowActive=True, threshold = 30000):
        """ analog sensors will need to be sent a threshold value to detect trip """
        
        super().__init__(pin, name, lowActive)
        self._pinio = ADC(self._pin)
        self._threshold = threshold

    def tripped(self)->bool:
        """ sensor is tripped if sensor value is higher or lower than threshold """
        
        v = self.rawValue()
        if (self._lowActive and v < self._threshold) or (not self._lowActive and v > self._threshold):
            Log.i(f"AnalogSensor {self._name}: sensor tripped")
            return True
        else:
            return False

    def rawValue(self):
        return self._pinio.read_u16()

class TempSensor(AnalogSensor):
    """
    Temperature sensor as a subclass of Analog Sensor - Temp sensor is a bit more
    defined since it technically returns a temperature. Note that thermistors are
    not totally accurate, but the teperature fluctuations - increases and decreases
    are what matters.
    """
    
    def __init__(self, pin, name='Temp Sensor', lowActive=False, threshold=60):
        """
        Create a new temp sensor - similar to regular analog sensor
        but now tripped will return true when temp is lower than threshold (lowActive=True)
        and higher than threshold (lowActive=False)
        """
        
        super().__init__(pin, name, lowActive, threshold)
        
    def rawValue(self):
        """
        Reture the temperature (approx) in fahrenheit
        """
        
        adcvalue = super().rawValue()
        voltage = adcvalue / 65535.0 * 5
        Rt = 10 * voltage / (5 -voltage)
        tempK = (1 / (1 / (273.15+25) + (math.log(Rt/10)) / 3950))
        tempF = int((tempK - 273.15) * 1.8) + 32
        return tempF
        
class UltrasonicSensor(Sensor):
    """
    A simple implementation of an ultrasonic sensor with digital IO
    pins for trigger and echo.
    
    While technically Ultrasonic sensor is not an analog sensor since it
    uses digital pins, it does have continuous data, so subclassing
    AnalogSensor makes more sense. But given AnalogSensor should only be
    used in ADC pins, it is better to subclass the Sensor superclass.
    
    Continuing to use the lowActive and threshold like AnalogSensor however.

    init by sending trigger, echo and optionally lowActive and threshold
    parameters. Threshold defaults to 10cm, and lowActive defaults to true
    so when distance is < 10cm, it will return true for tripped.
    """

    def __init__(self, *, trigger=0, echo=1, name='Ultrasonic', lowActive = True, threshold=10.0):
        super().__init__(trigger, name, lowActive)
        self._trigger = Pin(trigger, Pin.OUT)
        self._echo = Pin(echo, Pin.IN)
        self._threshold = threshold

    def getDistance(self)->float:
        """ Get the distance of obstacle from the sensor in cm """
        
        self._trigger.off()
        utime.sleep_us(2)
        self._trigger.on()
        utime.sleep_us(5)
        self._trigger.off()
        while self._echo.value() == 0:
            signaloff = utime.ticks_us()
        while self._echo.value() == 1:
            signalon = utime.ticks_us()
        timepassed = signalon - signaloff
        distance = (timepassed * 0.0343) / 2
        return distance

    def tripped(self)->bool:
        """ sensor is tripped if distance is higher or lower than threshold """
        
        v = self.getDistance()
        if (self._lowActive and v < self._threshold) or (not self._lowActive and v > self._threshold):
            Log.i(f"UltrasonicSensor {self._name}: sensor tripped")
            return True
        else:
            return False

# DHT11/DHT22 Sensor
class DHTSensor(DigitalSensor):
    def __init__(self, pin, name='DHT', lowActive=False, threshold=60, poll_delay=2000, sensor_type='DHT11'):
        """
        Create a new DHT sensor - similar to regular digital sensor but can take
        either the form of a DHT11 or DHT22 based on the sensor_type parameter

        DHT11 is less accurate but cheaper, DHT22 is more accurate but more expensive

        Note that the DHT sensor is a digital sensor but it returns two values - temperature
        and humidity. So we subclass DigitalSensor but override the rawValue method

        Also, the DHT sensor is a bit slow, so we will not poll it as frequently as other sensors.
        To avoid to much polling, a default poll parameter is set to 2 seconds.

        The threshold is set to 60F by default, but can be changed. This is used to determine
        if the sensor is tripped or not. Only the temperature is used for tripping.
        """
        
        super().__init__(pin, name, lowActive)
        self._sensor_type = sensor_type
        self._sensor_class = dht.DHT11 if sensor_type == "DHT11" else dht.DHT22
        self._dht_sensor = self._sensor_class(Pin(self._pin))
        self._last_poll_time = 0
        self._poll_delay = poll_delay
        self._threshold = threshold

    def getTemperature(self):
        """
        Return the temperature of the sensor
        """
        
        if utime.ticks_ms() - self._last_poll_time > self._poll_delay:
            self._dht_sensor.measure()
        self._last_poll_time = utime.ticks_ms()
        return self._dht_sensor.temperature()

    def getHumidity(self):
        """
        Return the humidity of the sensor
        """
        
        if utime.ticks_ms() - self._last_poll_time > self._poll_delay:
            self._dht_sensor.measure()
        self._last_poll_time = utime.ticks_ms()
        return self._dht_sensor.humidity()

    def rawValue(self):
        """
        Returns a tuple of temperature and humidity
        """
        
        if utime.ticks_ms() - self._last_poll_time > self._poll_delay:
            self._dht_sensor.measure()
        self._last_poll_time = utime.ticks_ms()
        return (self._dht_sensor.temperature(), self._dht_sensor.humidity())

    def tripped(self)->bool:
        """
        Sensor is tripped if temperature is higher or lower than threshold
        """
        
        if self._lowActive:
            return self.getTemperature() < self._threshold
        else:
            return self.getTemperature() >= self._threshold


Sensors.py

"""
# StateModel.py
# A State model implementation
# Author: Arijit Sengupta
"""
import time
from Log import *
import gc

class StateModel:
    """
    A really simple implementation of a generic state model
    Keeps track of a number of states by sending the total number
    of states to the constructor. State numbers always start from 0
    which is the start state.

    Also takes a handler which is just a reference to a class that has
    three responder methods. The responder methods for stateEntered and
    stateLeft receives the state that was entered or left,
    with the event code that caused it. stateDo only receives the current
    state.
    
        stateEntered(state, event)
        stateLeft(state, event)
        stateDo(state)

    Currently the following types of events are supported.
    
    * Button events - these are created by calling the addButton method. The button's
      existing handler will be replaced with the model's handler, and two events of the
      following form will be enabled: [name]_press and [name]_release. Note
      that two buttons cannot have the same name.
    * Timer events - these are generated by software or hardware timers. Created by calling
      the addTimer method - will create an event [name}_timeout. Again, two timers
      cannot have the same name.
    * "no_event" is for non-event-related transitions. So if a state performs 
       the entry actions and do actions and then immediately goes to the next state, 
       no_event can be used.
    * Custom events - if a condition event needs to be executed, call the addCustomEvent
      method with the name of the event. This name can now be used for transitions, but the
      Controller must check the condition itself, and then call processEvent("eventname")
      when the codnition is satisfied.

    The calling class or the handler must override stateEntered and
    stateLeft to perform actions as per the state model

    After creating the state, call addTransition to determine
    how the model transitions from one state to the next.

    As events start coming in, call processEvent on the event to
    have the state model transition as per the transition matrix.
    """
    
    def __init__(self, numstates, handler, debug=False):
        """
        The statemodel constructor - needs 2 things minimum:
        Parameters
        ----------
        numstates - the number of states in the State model (includes the start and end states)
        handler - the handler class that should implement the model actions stateEntered and stateLeft
         - stateEntered will receive as parameter which state the model has entered - this should
            allow the handler to execute entry actions
         - stateLeft will receive as parameter which state the model left - this will allow the handler
            to execute the exit actions.
        all continuous in-state actions must be implemented in the handler in a execute loop.
        
        debug will print things to the screen like active state, transitions, events, etc.
        """
        
        self._numstates = numstates
        self._running = False
        self._transitions = []
        for i in range(0, numstates):
            self._transitions.append(None)
        self._curState = -1
        self._handler = handler
        self._debug = debug
        self._events = ['no_event']
        self._buttons = []
        self._timers = []
        self._submodels = {}

    def addTransition(self, fromState, events, toState):
        """
        Add a transition to the state model. The transition is defined by the
        source state, an array of events that will cause the transition, and the
        destination state. The events array can have multiple events that will all
        cause the same transition.
        """

        for event in events:
            if event in self._events:
                if not self._transitions[fromState]:
                    self._transitions[fromState] = []
                self._transitions[fromState].append((event,toState))
            else:
                raise ValueError(f"Invalid event {event}")
            
    def findInvalidEvent(self, transitions):
        # Check if the events are valid
        for row in transitions:
            for (e,s) in row:
                if e not in self._events:
                    return e
        return None

    def setTransitionTable(self, transitions):
        """
        Set the entire transition table at once. The transitions should be in the form
        of a matrix of tuples. Each row of the matrix corresponds to one source state
        and the values in the matrix should be in the form of a tuple (event, destination).

        For example, if you have 3 states and the transitions are as follows:
        0 -> 1 on event1, 0 -> 2 on event2, 1 -> 2 on event3, 2 -> 0 on event4, 2 -> 1 on event5

        Then the transition matrix should be:
        [
            [('event1', 1), ('event2', 2)],
            [('event3', 2)],
            [('event4', 0), ('event5', 1)]
        ]

        Note that only basic error checks are performed in this method. It is the responsibility
        of the calling class to ensure that the transition table is correct.
        """
        
        e = self.findInvalidEvent(transitions)
        if e:
            raise ValueError(f"Invalid event {e}")
        else:
            # Check if the number of rows in the transition matrix is the same as the number of states
            if len(transitions) != self._numstates:
                self._numstates = len(transitions)
                Log.e(f"Number of states in the transition matrix does not match the number of states in the model. Resetting the number of states to {self._numstates}")
            self._transitions = transitions

    def addSubTransitionTable(self, subname, transitions):
        """
        Add a subtransition table. This should add the starting
        point of the transition for the name to the numstates + 1
        then update numstates and add the new transitions to the table.
        
        Same error checks as before?
        """
        
        e = self.findInvalidEvent(transitions)
        if e:
            raise ValueError(f"Invalid event {e}")
        else:
            if subname in self._submodels:
                raise ValueError(f'Submodel {subname} already added!')
            else:
                self._submodels[subname] = self._numstates
                for tr in transitions:
                    print( tr)
                    r = []
                    for (e,s) in tr:
                        r.append((e,s+self._numstates))
                    self._transitions.append(r)
                self._numstates += len(transitions)
                    
        
    def getTransition(self, fromState, event):
        """
        Get the distination for this transition
        """

        for (e,s) in self._transitions[fromState]:
            if e == event:
                return s
        return -1
        
    
    def start(self):
        """ start the state model - always starts at state 0 as the start state """
        
        self._curState = 0
        self._running = True
        self._handler.stateEntered(self._curState, "no_event")  # start the state model

    def stop(self):
        """
        stop the state model - this will call the handler one last time with
        what state was stopped at, and then set the running flag to false.
        """
    
        if self._running:
            self._handler.stateLeft(self._curState, "no_event")
        self._running = False
        for b in self._buttons:
            b.setHandler(None)
        for t in self._timers:
            t.setHandler(None)
            t.cancel()
        self._curState = -1

    def startSubmodel(self, subname):
        if subname in self._submodels:
            st = self._submodels[subname]
            self.gotoState(st)
        else:
            raise ValueError(f'Invalid submodel {subname}')
            
    def gotoState(self, newState, event="no_event"):
        """
        force the state model to go to a new state. This may be necessary to call
        in response to an event that is not automatically handled by the Model class.
        This will correctly call the stateLeft and stateEntered handlers
        """
        
        if (newState < self._numstates):
            if self._debug:
                Log.d(f"Going from State {self._curState} to State {newState} on event {event}")
            self._handler.stateLeft(self._curState, event)
            self._curState = newState
            self._handler.stateEntered(self._curState, event)

    def processEvent(self, event):
        """
        Get the model to process an event. The event should be one of the events defined
        at the top of the model class. Currently 4 button press and release events, and
        a timeout event is supported. Handlers for the buttons and the timers should be
        incorporated in the main class, and processevent should be called when these handlers
        are triggered.
        
        I may try to improve this design a bit in the future, but for now this is how it is
        built.
        """
        
        if (event in self._events):
            
            newstate = self.getTransition(self._curState, event)
            if newstate >= 0:
                if self._debug:
                    Log.d(f"Processing event {event}")
                self.gotoState(newstate, event)
            else:
                if self._debug:
                    if event != "no_event":
                        Log.d(f"Ignoring event {event}")
        else:
            Log.e(f"Invalid event {event}")

    def run(self, delay=0.1):        
        # Start the model first
        self.start()
        # Then it should do a continous loop while the model runs
        while self._running:
            # Inside, you can use if statements do handle various do/actions
            # that you need to perform for each state
            # Do not perform entry and exit actions here - those are separate
                        
            self._handler.stateDo(self._curState)

            # Ping any software timer in the model
            for timer in self._timers:
                if type(timer).__name__ == 'SoftwareTimer':
                    timer.check()
            
            # I suggest putting in a short wait so you are not overloading the poor Pico
            if delay > 0:
                time.sleep(delay)

            # If there is any no_event transition, lets process that now
            self.processEvent("no_event")


    def addButton(self, btn):
        btnname = btn._name
        event1 = f'{btnname}_press'
        event2 = f'{btnname}_release'
        
        if event1 in self._events or event2 in self._events:
            raise ValueError(f'There is already a button with the name {btnname}')
        else:
            self._events.append(event1)
            self._events.append(event2)
            # Since we use a HAL we don't need this
            # btn.setHandler(self)
            self._buttons.append(btn)            

    def buttonPressed(self, name):
        """ 
        The internal button handler - now Model can take care of buttons
        that have been added using the addButton method.
        """

        self.processEvent(f'{name}_press')

    def buttonReleased(self, name):
        """
        Same thing with Button release, if you want to handle release events
        As well as press or just want to do release events only.
        """

        self.processEvent(f'{name}_release')
        
    def addTimer(self, timer):
        """
        Add a timer to the state model. All timers must have distinct names
        Exception will be raised if a timer with the same name is added.
        """
        
        eventname = f'{timer._name}_timeout'
        if eventname in self._events:
            raise ValueError(f'A timer with name {timer._name} already exists')
        else:
            self._events.append(eventname)
            timer.setHandler(self)
            self._timers.append(timer)

    def addCustomEvent(self, event):
        """
        Add custom events. This simply defines the event names for transition.
        The StateModel does not have the ability to detect these events - the
        Controller must detect the events and call processEvent to handle any
        transition based on the event.

        All events must have distinct names. Exception will be raised if the
        event already exists.
        """
        if event in self._events:
            raise ValueError(f'An event with the name {event} already exists')
        else:
            self._events.append(event)
        
    """
    If you are using a timer, handle the timeout callback
    My model can use timeout events for transitions, so simply
    send the event to the model and it will take care of
    the rest.
    """
    def timeout(self, name):
        eventname = f'{name}_timeout'
        self.processEvent(eventname)


if __name__ == '__main__':
    s = StateModel(3, None)
    s.addCustomEvent('event1')
    s.addCustomEvent('event2')
    s.addCustomEvent('event3')
    s.addCustomEvent('event4')
    s.addCustomEvent('event5')
    tr = [
            [('event1', 1), ('event2', 2)],
            [('event3', 2)],
            [('event4', 0), ('event5', 1)]
        ]

    tr1 = [
            [('event1', 1), ('event2', 2)],
            [('event3', 2)],
            [('event4', 0), ('event5', 1)]
        ]

    s.setTransitionTable(tr)
    s.addSubTransitionTable('sub', tr1)
    