Maprika sqlite database to GPX track converter

db_to_gpx.py

"""
Written by GPT3 from this English prompt (with one tweak to the prompt, to get 
the timestamp parameter to not error out, and PEP8 fixes):

----

1. Open a sqlite database with a name like `2022-07-17 17.48.19.db` or
    `2021-04-11 08.44.16.db`
2. Inside is a table called `locations`, with headers [LOCTYPE INTEGER,
    TIMESTAMP BIGINT, LATITUDE REAL, LONGITUDE REAL,ALTITUDE REAL, ACCURACY
    REAL, SPEED REAL, BEARING REAL, LOCNAME VARCHAR].  Each row contains a GPS
    measurement.  The timestamps are stored using the unix epoch format.
3. Extract the timestamp, latitude, and longitude for all the rows from the
    `locations` table.
4. Using the gpxpy library, create a .gpx file
5. Convert the timestamps (such as 1043011384999) into GPX format (Coordinated
    Universal Time (UTC) using ISO 8601 format).
6. Insert the rows into the GPX file as a track.
7. Save the .gpx file with the same base name as the .db file.
"""

import sqlite3
import gpxpy
import gpxpy.gpx
import os
import datetime


def convert_db_to_gpx(db_file):
    """
    Convert a sqlite database file to a gpx file.
    """
    # Open the database file
    conn = sqlite3.connect(db_file)
    c = conn.cursor()

    # Extract the data from the database
    c.execute("SELECT * FROM locations")
    rows = c.fetchall()

    # Create a GPX file
    gpx = gpxpy.gpx.GPX()

    # Create a GPX track
    gpx_track = gpxpy.gpx.GPXTrack()
    gpx.tracks.append(gpx_track)

    # Create a GPX segment
    gpx_segment = gpxpy.gpx.GPXTrackSegment()
    gpx_track.segments.append(gpx_segment)

    # Add the data to the GPX segment
    for row in rows:
        gpx_segment.points.append(gpxpy.gpx.GPXTrackPoint(
            row[2], row[3], time=datetime.datetime.fromtimestamp(row[1]/1000)))

    # Save the GPX file
    gpx_file = open(db_file.replace('.db', '.gpx'), 'w')
    gpx_file.write(gpx.to_xml())
    gpx_file.close()


if __name__ == "__main__":
    # Loop through all the .db files in the current directory
    for file in os.listdir('.'):
        if file.endswith('.db'):
            convert_db_to_gpx(file)