from machine import Pin, SPI, I2C
import os
import sdcard
from time import ticks_ms, sleep_ms
import ssd1306

# SPI configuration for SD card
spi = SPI(2, baudrate=2000000, polarity=0, phase=0, sck=Pin(18), mosi=Pin(23), miso=Pin(19))
cs = Pin(5, Pin.OUT)

# Initialize SD card
sd = sdcard.SDCard(spi, cs)
os.mount(sd, "/sd")

# I2C configuration for OLED
i2c = I2C(0, scl=Pin(22), sda=Pin(21))  # GPIO 22 = SCL, GPIO 21 = SDA
oled_width = 128
oled_height = 64
oled = ssd1306.SSD1306_I2C(oled_width, oled_height, i2c)

# Function to display messages on OLED
def display_message(line1="", line2="", line3=""):
    oled.fill(0)  # Clear screen
    oled.text(line1, 0, 0)
    oled.text(line2, 0, 20)
    oled.text(line3, 0, 40)
    oled.show()

# Pin assignments
cap = Pin(21, Pin.IN)  # Soil moisture sensor
button_1 = Pin(26, Pin.IN, Pin.PULL_DOWN)
button_2 = Pin(25, Pin.IN, Pin.PULL_DOWN)
blue = Pin(2, Pin.OUT)

# Variables
toggle_1 = False
toggle_2 = False
last_press_1 = 0
last_press_2 = 0
button_1_last = 0
button_2_last = 0
recording = False
start_time = 0
calibration = {"air": 0, "water": 100}

# Calibration function
def calibrate_sensor():
    global calibration
    display_message("Calibration:", "Hold in Air", "Press Both Buttons")
    blue.value(1)  # Turn on blue LED
    stable = False
    while not stable:
        if button_1.value() and button_2.value():
            air_value = cap.value()
            display_message("Air Value:", str(air_value), "Release Buttons")
            while button_1.value() or button_2.value():
                pass
            stable = True
            calibration["air"] = air_value
    display_message("Calibration:", "Hold in Water", "Press Both Buttons")
    stable = False
    while not stable:
        if button_1.value() and button_2.value():
            water_value = cap.value()
            display_message("Water Value:", str(water_value), "Release Buttons")
            while button_1.value() or button_2.value():
                pass
            stable = True
            calibration["water"] = water_value
    blue.value(0)  # Turn off blue LED
    display_message("Calibration Done!", "", "")
    sleep_ms(2000)

# Function to map sensor value to percentage
def map_moisture(value, air, water):
    return int((value - air) / (water - air) * 100)

# Check buttons
def check_buttons():
    global toggle_1, toggle_2, last_press_1, last_press_2, button_1_last, button_2_last, recording, start_time
    time_now = ticks_ms()

    # Button 1 logic
    button_1_now = button_1.value()
    if button_1_now != button_1_last:
        button_1_last = button_1_now
        if button_1_now == 1:  # Button press
            toggle_1 = not toggle_1
            last_press_1 = time_now
            recording = toggle_1
            if recording:
                start_time = ticks_ms()
                display_message("Recording:", "Started", "")
            else:
                display_message("Recording:", "Stopped", "")
        sleep_ms(5)

    # Button 2 logic
    button_2_now = button_2.value()
    if button_2_now != button_2_last:
        button_2_last = button_2_now
        if button_2_now == 1:  # Button press
            toggle_2 = not toggle_2
            last_press_2 = time_now
            if not recording:
                save_to_sd()
            display_message("Saving Data...", "", "")
        sleep_ms(5)

# Save data to SD card
def save_to_sd():
    try:
        filename = "/sd/moisture_data.csv"
        with open(filename, "w") as file:
            file.write("Time (minutes),Moisture (%)\n")
            for entry in data_log:
                file.write(f"{entry[0]},{entry[1]}\n")
        display_message("Data Saved!", filename, "")
    except Exception as e:
        display_message("Error:", str(e), "")

# Main loop
data_log = []
calibrate_sensor()
while True:
    check_buttons()

    if recording:
        elapsed_time = (ticks_ms() - start_time) // 60000  # Convert ms to minutes
        moisture = cap.value()
        moisture_percent = map_moisture(moisture, calibration["air"], calibration["water"])
        data_log.append((elapsed_time, moisture_percent))
        display_message(f"Time: {elapsed_time} min", f"Moisture: {moisture_percent}%", "")
        sleep_ms(1000)