import os
import gpxpy
import gpxpy.gpx
from datetime import datetime, timedelta
from geopy.distance import geodesic

start_time = ['2022-04-01 17:34']

old = '<gpx creator="Health" xsi:schemaLocation="http://www.topografix.com/GPX/1/0 \
http://www.topografix.com/GPX/1/0/gpx.xsd" version="1.0" \
xmlns="http://www.topografix.com/GPX/1/0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">'
new = '<gpx xmlns="http://www.topografix.com/GPX/1/1" \
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" \
xsi:schemaLocation="http://www.topografix.com/GPX/1/1 \
http://www.topografix.com/GPX/1/1/gpx.xsd" version="1.1" \
creator="gpx.py -- https://github.com/tkrajina/gpxpy">\n'

def file_format(file):
    f = open('./old/'+file, 'r', encoding='utf-8')
    s = f.readline()
    s = s.replace(old, new)
    s = '<?xml version="1.0" encoding="UTF-8"?>\n' + s
    with open('./old/'+file, 'w', encoding='utf-8') as f:
        f.write(s)

def process(file, index):
    gpx_file = open('./old/'+file, 'r', encoding='utf-8')
    gpx = gpxpy.parse(gpx_file)

    s = 0
    p = None
    for track in gpx.tracks:
        time = float(track.extensions[0].text)
        for segment in track.segments:
            for point in segment.points:
                if p:
                    s += geodesic((point.latitude, point.longitude), (p.latitude, p.longitude)).m
                p = point

    ngpx = gpxpy.gpx.GPX()

    gpx_track = gpxpy.gpx.GPXTrack()
    ngpx.tracks.append(gpx_track)

    gpx_segment = gpxpy.gpx.GPXTrackSegment()
    gpx_track.segments.append(gpx_segment)

    p = None
    time0 = datetime.strptime(start_time[index], '%Y-%m-%d %H:%M') - timedelta(hours=8)
    for track in gpx.tracks:
        for segment in track.segments:
            for point in segment.points:
                if p and point.latitude == p.latitude and point.longitude == p.longitude:
                    continue
                if p:
                    dis = geodesic((point.latitude, point.longitude), (p.latitude, p.longitude)).m
                    dtime += time * dis / s
                else:
                    dtime = 0
                gpx_segment.points.append(gpxpy.gpx.GPXTrackPoint(point.latitude, point.longitude,
                                                                  time=time0 + timedelta(seconds=dtime)))
                # datetime.strftime(time0 + timedelta(seconds=dtime), '%Y-%m-%dT%H:%M:%S.%fZ')
                p = point

    with open('./new/'+file, 'w', encoding='utf-8') as f:
        f.write(ngpx.to_xml())

files = os.listdir('./old')
for k in range(len(files)):
    file_format(files[k])
    process(files[k], k)
    os.remove('./old/' + files[k])