#################################################################################
#           Temperature and Humidity monitoring using Thingspeak                #
#################################################################################
#
# Temperature and Humidity monitoring using Thingspeak IoT platform
#
# DHT22 sensor +  OLED display with Raspberry Pi Pico / W 
#
# Check out the link for Code explanation and Hardware details
# Link: 
#   http://tech.arunkumarn.in/blogs/raspberry-pi-pico/
#
# 

from machine import Pin, I2C
import dht
import time
import json
import framebuf

from icons import pico_logo
from ssd1306 import SSD1306_I2C


# Display interface
i2c=I2C(1,scl=Pin(3),sda=Pin(2),freq=400000)
display = SSD1306_I2C(128, 64, i2c)

# Sensor interface
sensor = dht.DHT22(Pin(21))


# Wifi Configeration
ssid = "Wokwi-GUEST"
password = "aavishkarah" 
wifi_connected = False

# Thingspeak Configeration
api_key = "API_KEY"
host = "api.thingspeak.com"


def erase_lines(y, line=1):
    display.rect(0,y, 128, 8*line, 0, True)


def blink_display(n=1, delay=250):
    for _ in range(n):
        display.invert(1)
        display.contrast(100)
        display.show()
        time.sleep_ms(delay)
        display.invert(0)
        display.contrast(0)
        display.show()
        time.sleep_ms(delay)


def display_datasent_status(status):
    erase_lines(40, 2)
    if status == "200":
        display.text("Data Sent", 24, 44)
    elif status == "400":
        display.text("400 ERROR", 24, 44)
        blink_display(2, 150)
    else:
        display.text("ERROR: Check WiFi", 0, 44)
        blink_display()
    display.show()
    time.sleep_ms(1000)
    erase_lines(40, 2)
    display.show()


def do_connect(ssid, password):
    global wifi_connected

    import network
    time.sleep_ms(2000)
    sta_if = network.WLAN(network.STA_IF)
    wifi_connected = sta_if.isconnected()
    
    if not wifi_connected:
        sta_if.active(True)
        sta_if.connect(ssid, password)
        loc = 10
        for i in range(10):
            display.text("*",loc,45)
            display.show()
            time.sleep_ms(2500)
            wifi_connected = sta_if.isconnected()
            if wifi_connected:
                display.fill(0)
                display.text('Wifi Connected',10,30)
                display.show()
                time.sleep_ms(1000)
                blink_display(4, 100)
                break
            loc += 10
        if not wifi_connected:
            display.fill(0)
            display.text(" NO INTERNET ",0,20)
            display.show()
            time.sleep_ms(2000)
            blink_display(4, 100)

    else:
        display_wifi_connected()


def send_data(temperature, humidity):
    try:
        import socket
        path = f"/update?api_key={api_key}&field1={temperature:0.2f}&field2={humidity:0.2f}"
        addr = socket.getaddrinfo(host, 80)[0][-1]
        s = socket.socket()
        s.connect(addr)
        s.send(bytes('GET /%s HTTP/1.0\r\nHost: %s\r\n\r\n' % (path, host), 'utf8'))
        
        while True:
            data = str(s.recv(1024)).replace('b','').replace("'", "")
            # print(data)
            if data:
                if data.startswith("HTTP/"):
                    status_code = data.split()[1]
            else:
                break
        s.close()

        display_datasent_status(status_code)
        
    except:
        display_datasent_status(False)
        global wifi_connected
        wifi_connected = False


def welcome_message():
    # display Raspberry Pi Pico Logo
    display.fill(0)
    display.blit(pico_logo, 48, 0)
    display.show()
    time.sleep_ms(2500)

    # display Aavishkarah 
    display.text('Welcome to',25,34)
    display.show()
    time.sleep_ms(250)
    display.text("Aavishkarah",20,45)
    display.show()
    time.sleep_ms(2500)


welcome_message()

display.fill(0)
display.text("Connecting to",10,20)
display.text("Wifi",45,34)
display.text("*",0,45)
display.show()
time.sleep_ms(50)

# connect to wifi
do_connect(ssid, password)

# Clear the display
display.fill(0)

while True:
    sensor.measure()
    temperature = sensor.temperature()
    humidity = sensor.humidity()
    
    # display temperature & humidity
    erase_lines(12, 3)
    display.text("Temper.t. :", 0, 12)
    display.text("Humidity  :", 0, 24)
    display.text(str(temperature), 85, 12)
    display.text(str(humidity), 85, 24)
    display.show()

    # Send data to thingspeak
    send_data(temperature, humidity)

    # Thingspeak accepts data for every 15 sec
    # 15 sec delay
    time.sleep_ms(15000)