"""
City module
SPDX - License - Identifier: LGPL - 3.0 - or -later
Copyright © 2020 Project Author Guille Gutierrez guillermo.gutierrezmorote@concordia.ca
"""
from __future__ import annotations
import sys
import pickle
from typing import List, Union

import pyproj
from pyproj import Transformer

from city_model_structure.building import Building
from city_model_structure.city_object import CityObject
from helpers.geometry_helper import GeometryHelper
import math


class City:
  """
  City class
  """

  def __init__(self, lower_corner, upper_corner, srs_name, buildings=None):
    self._name = None
    self._lower_corner = lower_corner
    self._upper_corner = upper_corner
    self._buildings = buildings
    self._srs_name = srs_name
    self._geometry = GeometryHelper()
    # todo: right now extracted at city level, in the future should be extracted also at building level if exist
    self._location = None
    self._country_code = None

  @property
  def _get_location(self):
    if self._location is None:
      gps = pyproj.CRS('EPSG:4326')  # LatLon with WGS84 datum used by GPS units and Google Earth
      try:
        input_reference = pyproj.CRS(self.srs_name)  # Projected coordinate system from input data
      except pyproj.exceptions.CRSError:
        sys.stderr.write('Invalid projection reference system, please check the input data. '
                         '(e.g. in CityGML files: srs_name)\n')
        sys.exit()
      transformer = Transformer.from_crs(input_reference, gps)
      coordinates = transformer.transform(self.lower_corner[0], self.lower_corner[1])
      self._location = GeometryHelper.get_location(coordinates[0], coordinates[1])
    return self._location

  @property
  def country_code(self):
    """
    City country code
    :return: str
    """
    return self._get_location[0]

  @property
  def name(self):
    """
    City name
    :return: str
    """
    return self._get_location[1]

  @property
  def city_objects(self) -> Union[List[CityObject], None]:
    """
    City objects belonging to the city
    :return: None or [CityObject]
    """
    return self.buildings

  @property
  def buildings(self) -> Union[List[Building], None]:
    """
    Buildings belonging to the city
    :return: None or [Building]
    """
    return self._buildings

  @property
  def trees(self) -> NotImplementedError:
    """
    Trees belonging to the city
    :return: NotImplementedError
    """
    raise NotImplementedError

  @property
  def bixi_features(self) -> NotImplementedError:
    """
    Bixi features belonging to the city
    :return: NotImplementedError
    """
    raise NotImplementedError

  @property
  def composting_plants(self) -> NotImplementedError:
    """
    Composting plants belonging to the city
    :return: NotImplementedError
    """
    raise NotImplementedError

  @property
  def lower_corner(self):
    """
    City lower corner
    :return: [x,y,z]
    """
    return self._lower_corner

  @property
  def upper_corner(self):
    """
    City upper corner
    :return: [x,y,z]
    """
    return self._upper_corner

  def city_object(self, name) -> Union[CityObject, None]:
    """
    Retrieve the city CityObject with the given name
    :param name:str
    :return: None or CityObject
    """
    for city_object in self.buildings:
      if city_object.name == name:
        return city_object
    return None

  def add_city_object(self, new_city_object):
    """
    Add a CityObject to the city
    :param new_city_object:CityObject
    :return: None
    """
    if new_city_object.type != 'building':
      raise NotImplementedError(new_city_object.type)
    if self._buildings is None:
      self._buildings = []
    self._buildings.append(new_city_object)

  @property
  def srs_name(self):
    """
    srs name
    :return: str
    """
    return self._srs_name

  @name.setter
  def name(self, value):
    """
    Set the city name
    :param value:str
    :return: None
    """
    self._name = value

  @staticmethod
  def load(city_filename) -> City:
    """
    Load a city saved with city.save(city_filename)
    :param city_filename: city filename
    :return: City
    """
    with open(city_filename, 'rb') as f:
      return pickle.load(f)

  def save(self, city_filename):
    """
    Save a city into the given filename
    :param city_filename: destination city filename
    :return:
    """
    with open(city_filename, 'wb') as f:
      pickle.dump(self, f)

  def region(self, center, radius):
    """
    Save a city into the given filename
    :param center: specific point in space [x, y, z]
    :param radius: distance to center of the sphere selected in meters
    :return: selected_region_city
    """
    selected_region_lower_corner = [center[0] - radius, center[1] - radius, center[2] - radius]
    selected_region_upper_corner = [center[0] + radius, center[1] + radius, center[2] + radius]
    selected_region_city = City(selected_region_lower_corner, selected_region_upper_corner, srs_name=self.srs_name)
    for city_object in self.city_objects:
      location = city_object.centroid
      distance = math.sqrt(math.pow(location[0]-center[0], 2) + math.pow(location[1]-center[1], 2)
                           + math.pow(location[2]-center[2], 2))
      if distance < radius:
        selected_region_city.add_city_object(city_object)
    return selected_region_city