#!/usr/bin/python
# -*- coding:utf-8 -*-
import RPi.GPIO as GPIO
import serial
import time, os
import csv
from datetime import datetime

myhost = os.uname()[1]

GPIO.setwarnings(False)

ser = serial.Serial('/dev/ttyS0',115200)
ser.flushInput()

rec_buff = ''
time_count = 0

# CSV file setup
csv_filename = f"gps_data_{datetime.now().strftime('%Y%m%d_%H%M%S')}.csv"

def convert_to_degrees(raw_value):
    decimal_value = float(raw_value)
    degrees = int(decimal_value / 100)
    d = float(degrees)
    m = (decimal_value - (d * 100)) / 60.0
    return d + m

def write_to_csv(timestamp, lat, lon):
    with open(csv_filename, 'a', newline='') as csvfile:
        csv_writer = csv.writer(csvfile)
        csv_writer.writerow([timestamp, lat, lon])

def send_at(command,back,timeout):
    rec_buff = ''
    ser.write((command+'\r\n').encode())
    time.sleep(timeout)
    if ser.inWaiting():
        time.sleep(0.01)
        rec_buff = ser.read(ser.inWaiting())
    if rec_buff != '':
        if back not in rec_buff.decode():
            print(command + ' ERROR')
            print(command + ' back:\t' + rec_buff.decode())
            return 0
        else:
            gps_data = rec_buff.decode()[13:-36]
            print(gps_data)
            
            # Parse GPS data
            gps_parts = gps_data.split(',')
            if len(gps_parts) >= 4 and gps_parts[0] and gps_parts[2]:
                lat = convert_to_degrees(gps_parts[0])
                lon = convert_to_degrees(gps_parts[2])
                if gps_parts[1] == 'S':
                    lat = -lat
                if gps_parts[3] == 'W':
                    lon = -lon
                
                timestamp = datetime.now().strftime('%Y-%m-%d %H:%M:%S')
                write_to_csv(timestamp, lat, lon)
                
                # Format for Google Maps
                maps_url = f"https://www.google.com/maps?q={lat},{lon}"
                print(f"Google Maps URL: {maps_url}")
                
            else:
                print("Invalid GPS data received")
            
            return 1
    else:
        print('GPS no está listo')
        return 0

def get_gps_position():
    rec_null = True
    answer = 0
    print('Iniciando GPS')
    rec_buff = ''
    send_at('AT+CGPS=1,1','OK',1)
    time.sleep(2)
    while rec_null:
        answer = send_at('AT+CGPSINFO','+CGPSINFO: ',1)
        if 1 == answer:
            answer = 0
            if ',,,,,,' in rec_buff:
                print('GPS no está listo')
                rec_null = False
                time.sleep(1)
        else:
            print('error %d'%answer)
            rec_buff = ''
            send_at('AT+CGPS=0','OK',1)
            return False
        time.sleep(1.5)

def power_on(power_key):
    print('SIM7600X is starting:')
    GPIO.setmode(GPIO.BCM)
    GPIO.setwarnings(False)
    GPIO.setup(power_key,GPIO.OUT)
    time.sleep(0.1)
    GPIO.output(power_key,GPIO.HIGH)
    time.sleep(2)
    GPIO.output(power_key,GPIO.LOW)
    time.sleep(20)
    ser.flushInput()
    print('SIM7600X is ready')

def power_down(power_key):
    print('SIM7600X is loging off:')
    GPIO.output(power_key,GPIO.HIGH)
    time.sleep(3)
    GPIO.output(power_key,GPIO.LOW)
    time.sleep(18)
    print('Good bye')

try:
    # No need to create CSV file with header anymore
    #power_on(power_key)
    get_gps_position()
    #power_down(power_key)
except:
    if ser != None:
        ser.close()
    #power_down(power_key)
    GPIO.cleanup()
if ser != None:
    ser.close()
    GPIO.cleanup()