"""Simple reader that reads OSMmap data from overpass API"""

from typing import List,Optional,Literal
import random
import string
import warnings
from llama_index.readers.base import BaseReader
from llama_index.readers.schema.base import Document
warnings.filterwarnings('ignore')




class OpenMap(BaseReader):
    """OpenMap Reader.

    Get the map Features from the overpass api(osm) for the given location/area 


    Args:
        localarea(str) -  Area or location you are seaching for 
        tag_values(str) -  filter for the give area 
        search_tag(str)  - Tag that you are looking for

        if you not sure about the search_tag and tag_values visit https://taginfo.openstreetmap.org/tags 

        remove_keys(list) - list of keys that need to be removed from the response 
                            by default  following keys will be removed ['nodes','geometry','members']

    """

    def __init__(self) -> None:
        """Initialize with parameters."""
        super().__init__()
    
    @staticmethod
    def _get_user()->str:
        # choose from all lowercase letter
        letters = string.ascii_lowercase
        result_str = ''.join(random.choice(letters) for i in range(10))
        return result_str
    
    @staticmethod    
    def _get_latlon(locarea:str,user_agent:str)->tuple:
        try:
            from geopy.geocoders import Nominatim 
        except:
            raise ImportError('install geopy using `pip3 install geopy`')

        geolocator = Nominatim(user_agent=user_agent)
        location = geolocator.geocode(locarea)
        return(location.latitude,location.longitude) if location else (None, None)
    
    def load_data(
        self, 
        localarea:str,
        search_tag:Optional[str] = 'amenity',
        remove_keys : Optional [List]= ['nodes','geometry','members'],
        tag_only:Optional[bool]=True ,
        tag_values:Optional[List]=[''],
        local_area_buffer : Optional[int] = 2000,
    ) -> List[Document]:
        
        """
        This loader will bring you the all the node values from the open street maps for the given location

        Args:

        localarea(str) -  Area or location you are seaching for 
        search_tag(str)  - Tag that you are looking for
        if you not sure about the search_tag and tag_values visit https://taginfo.openstreetmap.org/tags 

        remove_keys(list) - list of keys that need to be removed from the response 
                            by default it those keys will be removed ['nodes','geometry','members']

        tag_only(bool) - if True it  return the nodes which has tags if False returns all the nodes  
        tag_values(str) -  filter for the give area 
        local_area_buffer(int) - range that you wish to cover (Default 2000(2km))
        """
        try:
            from osmxtract import overpass, location 
            from osmxtract.errors import OverpassBadRequest
        except:
            raise ImportError('install osmxtract using `pip3 install osmxtract`')
        
        null_list=['','null','none',None]
        extra_info={}
        local_area=localarea

        if (local_area.lower().strip() in null_list):
            raise Exception('The Area should not be null')
        
        user=self._get_user()
        lat, lon = self._get_latlon(local_area,user)
        try:
            bounds = location.from_buffer(lat, lon, buffer_size=int(local_area_buffer))
        except TypeError:
            raise TypeError('Please give valid location name or check for spelling')
    
        #overpass query generation and execution
        tag_values=[str(i).lower().strip() for i in tag_values ]
        query = overpass.ql_query(bounds, tag=search_tag.lower(), values=tag_values,timeout=500)

        extra_info['overpass_query']=query
        try:
            response = overpass.request(query)
            
        except OverpassBadRequest : 
            raise TypeError(f'Error while executing the Query {query} please check the Args')
        
        res=response['elements']

        _meta=response.copy()
        del _meta['elements']
        extra_info['overpass_meta']=str(_meta)
        extra_info['lat']=lat
        extra_info['lon']=lon
        # filtering for only the tag values 
        filtered=[i for i in res if 'tags' in i.keys()] if tag_only else res

        for key in remove_keys:
            extras_poped =[i.pop(key,None) for i in filtered ]
        if filtered:
            return Document(str(filtered),extra_info=extra_info)
        else:
            return Document(str(res),extra_info=extra_info)