import datetime
import gpxpy
import gpxpy.gpx
from sqlalchemy.orm import Session
from geojson import Feature, LineString, FeatureCollection
from geopy.distance import geodesic

from errors.NotFoundException import NotFoundError
from modules.geoObjects import Driver, Track, Vehicle, Waypoint

class GPXHandler:
    __dbSession: Session
    
    def __init__(self, session:Session):
        self.__dbSession = session
        pass
    
    # handles converting a gpx file into usable data
    def parse(self, file, driver:Driver, vehicle:Vehicle):
        print(f"filename: {file}")
        self.__gpx = gpxpy.parse(open(f"./uploads/{file}"))

        if not driver:
            raise ValueError("no driver found")

        if not vehicle:
            raise ValueError("no vehicle found")
        
        if not file:
            raise ValueError("no file found")

        for track in self.__gpx.tracks:
            # sets track name
            # if no name is found at a track default to using date
            trackName = track.name or f"Track-{datetime.now().isoformat()}"
            
            # initializes track values
            self.startTime = None 
            self.endTime = None
            self.trackDistance = 0
            self.waypoints = []

            # grab all waypoints from a track
            for segment in track.segments:
                for point in segment.points:
                    self.waypoints.append(point)
                    if self.startTime is None or point.time < self.startTime:
                        self.startTime = point.time
                    if self.endTime is None or point.time > self.endTime:
                        self.endTime = point.time
                        
            # calculate distance between 2 waypoints
            for i in range(1, len(self.waypoints)):
                self.trackDistance += self.waypoints[i - 1].distance_3d(self.waypoints[i])
        
            # push values to the database
            track = Track(
                trackName=trackName,
                vehicle=vehicle,
                driver=driver,
                date=self.startTime.date() if self.startTime else None,
                distance=self.trackDistance,
                speed=0,
            )
                    
            self.__dbSession.add(track)
            self.__dbSession.commit()
        
            for point in self.waypoints:
                waypoint = Waypoint(
                    lat=point.latitude,
                    lon=point.longitude,
                    ele=point.elevation,
                    speed=None,
                    time=point.time,
                    track=track
                )
                self.__dbSession.add(waypoint)

            self.__dbSession.commit()
        
    # handles a route from db and converting it into geoJSON
    def getTrack(self, trackID):
        track = self.__dbSession.query(Track).filter_by(id=trackID).first()
        if not track:
            raise NotFoundError(f"track with id {trackID} not found", errors=[])

        # fetches waypoints for a given track and converts them into geoJSON
        waypoints = track.waypoints

        coordinates = [(wp.lon, wp.lat) for wp in waypoints]
        feature = Feature(geometry=LineString(coordinates))
        return feature
    
    # handles getting all infos of a track from the database
    def getTrackMeta(self, trackID):
        track = self.__dbSession.query(Track).filter_by(id=trackID).first()
        if not track:
            raise NotFoundError(f"track with id {trackID} not found", errors=[])

        trackObject = {
            "id": track.id,
            "name": track.trackName,
            "driver": {
                "id": track.driver.id,
                "name": track.driver.name
            } if track.driver else None,
            "vehicle": {
                "id": track.vehicle.id,
                "name": track.vehicle.name,
                "licenseplate": track.vehicle.licenseplate
            } if track.vehicle else None,
            "distance": track.distance,
            "time": track.date,
        }
        
        return trackObject
    
    
    # grabs only the tracks from the database and returns them as json object
    def getTracks(self):
        tracks = self.__dbSession.query(Track).all()

        track_list = [
            {
                "id": track.id,
                "name": track.trackName,
                "time": track.date,
            }
            for track in tracks # iterates all tracks and appends them to the list
        ]

        return track_list
    
    def getTracksInTime(self, start, end):
        tracks = self.__dbSession.query(Track).filter(Track.date.between(start, end)).all()
        
        track_list = [
            {
                "id": track.id,
                "name": track.trackName,
                "driver": {
                    "id": track.driver.id,
                    "name": track.driver.name
                } if track.driver else None,
                "vehicle": {
                    "id": track.vehicle.id,
                    "name": track.vehicle.name
                } if track.vehicle else None,
                "distance": track.distance,
                "time": track.date,
            }
            for track in tracks # iterates all tracks and appends them to the list
        ]

        return track_list
    
    def deleteTrack(self, trackid):
        self.__dbSession.query(Waypoint).filter(Waypoint.track_id == trackid).delete()
        self.__dbSession.query(Track).filter(Track.id == trackid).delete()
        self.__dbSession.commit()