#!/usr/bin/env python3
import json
import os
from datetime import datetime
from collections import defaultdict

def parse_coordinates(latlng_str):
    """
    Parse LatLng values in the format "50.6335999°, 6.6983381°"
    Returns a tuple of (latitude, longitude) as floats
    """
    if not latlng_str:
        return None, None
    
    try:
        # Remove degree symbols and split by comma
        latlng_str = latlng_str.replace('°', '')
        parts = latlng_str.split(',')
        
        if len(parts) != 2:
            return None, None
            
        lat = float(parts[0].strip())
        lng = float(parts[1].strip())
        return lat, lng
    except (ValueError, IndexError):
        return None, None

def create_gpx_header():
    """Create a GPX file header with proper namespaces"""
    return '''<?xml version="1.0" encoding="UTF-8"?>
<gpx version="1.1" 
     creator="Timeline-to-GPX converter"
     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">
'''

def create_gpx_footer():
    """Create a GPX file footer"""
    return '</gpx>'

def create_track_header(date):
    """Create a track header with the date as name"""
    return f'''  <trk>
    <name>Track {date}</name>
    <trkseg>
'''

def create_track_footer():
    """Create a track footer"""
    return '''    </trkseg>
  </trk>
'''

def create_trackpoint(lat, lon, altitude, timestamp):
    """
    Create a GPX trackpoint with the given coordinates, elevation, and time
    """
    trackpoint = f'''      <trkpt lat="{lat}" lon="{lon}">
'''
    
    if altitude is not None:
        trackpoint += f'        <ele>{altitude}</ele>\n'
    
    if timestamp:
        trackpoint += f'        <time>{timestamp}</time>\n'
        
    trackpoint += '      </trkpt>\n'
    return trackpoint

def process_timeline_json(input_file):
    """
    Process the Timeline.json file and generate GPX files by day
    """
    print(f"Processing {input_file}...")
    
    try:
        with open(input_file, 'r') as f:
            data = json.load(f)
    except (json.JSONDecodeError, FileNotFoundError) as e:
        print(f"Error reading JSON file: {e}")
        return
    
    # Group points by date
    points_by_date = defaultdict(list)
    skipped_points = 0
    total_points = 0
    
    # Process points from rawSignals
    print("Processing rawSignals data...")
    for signal in data.get('rawSignals', []):
        position = signal.get('position', {})
        timestamp_str = position.get('timestamp')
        
        # Skip points with null timestamps
        if not timestamp_str:
            skipped_points += 1
            continue
        
        try:
            # Parse timestamp and extract date
            timestamp_dt = datetime.fromisoformat(timestamp_str.replace('Z', '+00:00'))
            date_str = timestamp_dt.strftime('%Y-%m-%d')
            
            # Parse coordinates
            lat, lng = parse_coordinates(position.get('LatLng'))
            if lat is None or lng is None:
                skipped_points += 1
                continue
                
            altitude = position.get('altitude')
            
            # Add point to the appropriate date
            points_by_date[date_str].append({
                'lat': lat,
                'lon': lng,
                'altitude': altitude,
                'timestamp': timestamp_str,
                'source': 'rawSignal'
            })
            total_points += 1
        except (ValueError, TypeError) as e:
            print(f"Error processing rawSignal point: {e}")
            skipped_points += 1
    
    # Process points from semanticSegments timelinePath
    print("Processing semanticSegments timelinePath data...")
    for segment in data.get('semanticSegments', []):
        timeline_path = segment.get('timelinePath', [])
        
        for path_point in timeline_path:
            point_str = path_point.get('point')
            timestamp_str = path_point.get('time')
            
            # Skip points with null data
            if not point_str or not timestamp_str:
                skipped_points += 1
                continue
            
            try:
                # Parse timestamp and extract date
                timestamp_dt = datetime.fromisoformat(timestamp_str.replace('Z', '+00:00'))
                date_str = timestamp_dt.strftime('%Y-%m-%d')
                
                # Parse coordinates
                lat, lng = parse_coordinates(point_str)
                if lat is None or lng is None:
                    skipped_points += 1
                    continue
                
                # Add point to the appropriate date (no altitude in timelinePath)
                points_by_date[date_str].append({
                    'lat': lat,
                    'lon': lng,
                    'altitude': None,
                    'timestamp': timestamp_str,
                    'source': 'semanticSegment'
                })
                total_points += 1
            except (ValueError, TypeError) as e:
                print(f"Error processing semanticSegment point: {e}")
                skipped_points += 1
    
    # Create GPX files for each day
    for date, points in points_by_date.items():
        if not points:
            continue
            
        # Extract year and month from date (format: YYYY-MM-DD)
        year, month, _ = date.split('-')
        
        # Create directory structure
        dir_path = os.path.join(year, month)
        os.makedirs(dir_path, exist_ok=True)
        
        # Update output file path
        output_file = os.path.join(dir_path, f"track_{date}.gpx")
        print(f"Creating {output_file} with {len(points)} trackpoints...")
        
        # Sort points by timestamp
        points.sort(key=lambda p: p.get('timestamp', ''))
        
        with open(output_file, 'w') as f:
            f.write(create_gpx_header())
            f.write(create_track_header(date))
            
            for point in points:
                f.write(create_trackpoint(
                    point['lat'],
                    point['lon'],
                    point['altitude'],
                    point['timestamp']
                ))
                
            f.write(create_track_footer())
            f.write(create_gpx_footer())
    
    print(f"Processing complete. Created {len(points_by_date)} GPX files.")
    print(f"Total points processed: {total_points}")
    if skipped_points > 0:
        print(f"Skipped {skipped_points} points due to missing or invalid data.")

if __name__ == "__main__":
    process_timeline_json("Timeline.json")