from bs4 import BeautifulSoup

import xml.etree.cElementTree as ET
import requests
from segment import soup_to_segment, Segment
from station_on_line import soup_to_station_on_line, Station_on_line
from stationsweb import get_page

import time

def distance_coords(c1,c2):
    latd1  = c1[0]
    longd1 = c1[1]
    latd2 = c2[0]
    longd2 = c2[1]
    R = 6378.137
    lat1 = math.radians(latd1)
    long1 = math.radians(longd1)
    lat2 = math.radians(latd2)
    long2 = math.radians(longd2)
    #d = 2R × sin⁻¹(√[sin²((θ₂ - θ₁)/2) + cosθ₁ × cosθ₂ × sin²((φ₂ - φ₁)/2)])
    d = 2*R*math.asin(math.sqrt(math.sin((lat1-lat2)/2)**2+math.cos(lat1)*math.cos(lat2)*math.sin((long2-long1)/2)**2))
    return(d)

class Line:
    def __init__(self,number,segments,stations_on_line):
        self.number = number
        self.segments = segments
        self.stations_on_line = stations_on_line
    def vertices(self):
        gpx_tree = ET.parse(f"../data/gpx/{self.number}.gpx")
        gpx_element = gpx_tree.getroot()
        trk_element = gpx_element[1]
        trkseg_element = trk_element[1]
        coords = []
        for trkpt_element in trkseg_element:
            coords.append((float(trkpt_element.attrib["lat"]),float(trkpt_element.attrib["lon"])))
        return(coords)
    @classmethod
    def fromXML(cls,line_element):
        number = int(line_element.attrib["number"])
        segments_element = line_element[0]
        segments=[]
        for segment_element in segments_element:
            segments.append(Segment.fromXML(segment_element))
        stations_on_line_element = line_element[1]
        stations_on_line = []
        for station_on_line_element in stations_on_line_element:
            stations_on_line.append(Station_on_line.fromXML(station_on_line_element))
        return(cls(number,segments,stations_on_line))
    def toXML(self):
        line_element = ET.Element("Line")
        line_element.attrib["number"]=str(self.number)

        segments_element = ET.Element("Segments")
        for segment in self.segments:
            segments_element.append(segment.toXML())
        line_element.append(segments_element)

        stations_on_line_element = ET.Element("Stations_on_line")
        for station_on_line in self.stations_on_line:
            stations_on_line_element.append(station_on_line.toXML())
        line_element.append(stations_on_line_element)
        return(line_element)

def stationsweb_url(number):
    return(f"https://www.stationsweb.nl/lijnlijst.asp?lijn={number}")

def table_to_segments(segments_table):
    segments = []
    for segment_soup in segments_table.findAll("tr"):
        segments.append(soup_to_segment(segment_soup))
    return(segments)

def table_to_stations_on_line(stations_on_line_table):
    stations_on_line = []
    even = False
    for station_on_line_soup in stations_on_line_table.findAll("tr"):

        #If this was not here every station station would come two times
        #In the list.
        if(even):
            even = False
            continue

        station_on_line = soup_to_station_on_line(station_on_line_soup)
        if(station_on_line!=None):
            stations_on_line.append(station_on_line)
        even = True
    return(stations_on_line)


def retrieve_line(number):
    stationsweb_page = get_page(stationsweb_url(number))
    stationsweb_soup = BeautifulSoup(stationsweb_page.text, "html.parser")

    tables = stationsweb_soup.findAll("table")
    try:
        segments_table = tables[3]
    except:
        print(f"The following url had an issue: {stationsweb_url(number)}, and the table array has length {len(tables)} and has the following contents {tables}")
    stations_on_line_table = tables[4]

    segments = table_to_segments(segments_table)
    stations_on_line = table_to_stations_on_line(stations_on_line_table)

    line = Line(number,segments,stations_on_line)
    return(line)