print("Hello, ESP32!")

#import all necessary modules/libraries
import hcsr04  # Sensor Library
import ssd1306  # OLED Library
from utime import sleep
from machine import SoftI2C, Pin, PWM
import urequests  # Library for HTTP requests

# Declare ultrasonic pin connection
ultrasonic_sensor = hcsr04.HCSR04(trigger_pin=12, echo_pin=14, echo_timeout_us=500 * 2 * 30)

# PIN Declaration for OLED
i2c_oleddisplay = SoftI2C(scl=Pin(22), sda=Pin(21))
oled_width = 128
oled_height = 64
oled = ssd1306.SSD1306_I2C(oled_width, oled_height, i2c_oleddisplay)

# Declare Buzzer Pin
buzzer = PWM(Pin(4), Pin.OUT)

# Declare LED Pins
LED_RED = Pin(25, Pin.OUT)
LED_GREEN = Pin(26, Pin.OUT)
LED_BLUE = Pin(27, Pin.OUT)

# WiFi and LINE Token
ssid = "Wokwi-GUEST"
password = ""
line_token = "k06MUJm9zbrlt9k9NXsyIPYY2IuIrCNiRn1yOMMJ54F"

# WiFi connection function
def connect_wifi():
    from network import WLAN, STA_IF
    wlan = WLAN(STA_IF)
    wlan.active(True)
    wlan.connect(ssid, password)
    while not wlan.isconnected():
        sleep(1)
    print("Connected to WiFi:", wlan.ifconfig())

# Send LINE notification
def send_line_notify(message):
    url = "https://notify-api.line.me/api/notify"
    headers = {
        "Authorization": "Bearer " + line_token,
        "Content-Type": "application/x-www-form-urlencoded",
    }
    data = "message=" + message
    try:
        response = urequests.post(url, data=data, headers=headers)
        response.close()
    except Exception as e:
        print("Error sending LINE notification:", e)

# Initialize WiFi
connect_wifi()

while True:
    # Measure distance
    object_detect_cm = ultrasonic_sensor.distance_cm()
    object_detect_mm = ultrasonic_sensor.distance_mm()

    # Display object distance on Serial Monitor
    print("Distance from an object in cm :", object_detect_cm)
    print("Distance from an object in mm :", object_detect_mm)
    print("---------------------------------------------------\n")

    # Display object distance on OLED Screen
    oled.fill(0)
    oled.text('Object Detected:', 0, 0, 1)
    oled.text(str(object_detect_cm), 0, 20, 1)
    oled.text('cm', 70, 20, 1)
    oled.text(str(object_detect_mm), 0, 40, 1)
    oled.text('mm', 70, 40, 1)
    oled.show()

    # LED Indicator for Distance
    if object_detect_cm <= 10:
        LED_RED.value(1)
        LED_GREEN.value(0)
        LED_BLUE.value(0)
        # Buzzer alert
        for i in range(5):
            buzzer.init(freq=1000, duty=512)
            sleep(0.5)
            buzzer.init(freq=1, duty=0)
            sleep(0.5)
        send_line_notify("Warning! Object detected at 10 cm.")
    elif 10 < object_detect_cm <= 20:
        LED_RED.value(0)
        LED_GREEN.value(1)
        LED_BLUE.value(0)
        send_line_notify("Object detected at 20 cm.")
    elif 20 < object_detect_cm <= 30:
        LED_RED.value(0)
        LED_GREEN.value(0)
        LED_BLUE.value(1)
        send_line_notify("Object detected at 30 cm.")
    else:
        LED_RED.value(0)
        LED_GREEN.value(0)
        LED_BLUE.value(0)

    # Sleep for 5 seconds before the next measurement
    sleep(5)