# ==========================================================
#  Reading Rotary Encoder Values - ESP32
#  MicroPython - Wokwi Simulation
# ==========================================================

from machine import Pin
import time

# ---------------- Pin Configuration ----------------


clk = Pin(12, Pin.IN, Pin.PULL_UP)
dt  = Pin(13, Pin.IN, Pin.PULL_UP)
sw  = Pin(14, Pin.IN, Pin.PULL_UP)

# ---------------- Global Variables ----------------
counter = 0                 # Encoder position counter
last_clk_state = clk.value()  # Last known state of CLK pin
position_changed = False    # Flag to indicate a new value should be printed
reset_flag = False          # Flag to indicate button was pressed

# ==========================================================
# Interrupt Handler: Encoder Rotation (CLK pin)
# ==========================================================
def encoder_callback(pin):
    global counter, last_clk_state, position_changed

    clk_state = clk.value()

    # Detect valid transition (falling edge on CLK)
    if clk_state != last_clk_state and clk_state == 0:
        dt_state = dt.value()

        if dt_state != clk_state:
            # Clockwise rotation
            counter += 1
        else:
            # Counter-clockwise rotation
            counter -= 1

        position_changed = True

    last_clk_state = clk_state


# ==========================================================
# Interrupt Handler: Push Button (SW pin) - Reset Counter
# ==========================================================
def button_callback(pin):
    global counter, reset_flag
    time.sleep_ms(50)   # Simple debounce
    if sw.value() == 0:
        counter = 0
        reset_flag = True


# ---------------- Attach Interrupts ----------------
clk.irq(trigger=Pin.IRQ_FALLING | Pin.IRQ_RISING, handler=encoder_callback)
sw.irq(trigger=Pin.IRQ_FALLING, handler=button_callback)

# ---------------- Startup Message ----------------
print("Rotary Encoder Reading Started...")
print("Current Position:", counter)

# ---------------- Main Loop ----------------
while True:
    if position_changed:
        print("Encoder Position:", counter)
        position_changed = False

    if reset_flag:
        print("Button Pressed! Encoder Reset to:", counter)
        reset_flag = False

    time.sleep(0.05)   # Small delay to reduce CPU load