# Get AWS IP address ranges
# Reference https://docs.aws.amazon.com/general/latest/gr/aws-ip-ranges.html

import urllib3
import logging
import json
import argparse


log = logging.getLogger(__name__)

class IpRanges:

    url = "https://ip-ranges.amazonaws.com/ip-ranges.json"

    def __init__(self, region, type="ipv4"):
        self.type = type
        self.region = region

    @property
    def type(self):
        return self._type
    
    @type.setter
    def type(self, value):
        allowed_types = ["ipv4", "ipv6"]
        if value not in allowed_types and not isinstance(value, str):
            raise ValueError("Type should be either ipv4 or ipv6")
        self._type = value

    @property
    def region(self):
        return self._region
    
    @region.setter
    def region(self, value):
        if not isinstance(value, str):
            raise TypeError("Region should be always in string")
        self._region = value
    
    @staticmethod
    def request(url, method: None):
        log.info('Making request to %s', url)
        try:
            http = urllib3.PoolManager()
            response = http.request(method, url)
            body = response.data
            try:
                return json.loads(body)
            except ValueError:
                return body

        except urllib3.exceptions.HTTPError as e:
            log.error("Request failed: %s", e)
        except urllib3.exceptions.NewConnectionError as e:
            log.error("Server connection failed: %s", e)
    
    def getPrefixes(self) -> dict:
        prefixes = {}
        resp = self.request(self.url, "GET")
        if self.type == "ipv4":
            values = resp['prefixes']
            identifier = "ip_prefix"
        else:
            values = resp['ipv6_prefixes']
            identifier = "ipv6_prefix"

        prefixes = {
            'identifier': identifier,
            'values' : values,
        }
        
        return prefixes
    
    def getValues(self) -> dict:
        values = {}
        prefixes = self.getPrefixes()
        prefix_id = prefixes['identifier']
        ip_prefixes = [prefix[prefix_id] for prefix in prefixes['values']]
        regions = [prefix['region'] for prefix in prefixes['values'] if prefix['region'] == self.region]
        services = [prefix['service'] for prefix in prefixes['values']]
        network_border_groups = [prefix['network_border_group'] for prefix in prefixes['values']]
        values = {
            'ip_prefixes' : ip_prefixes,
            'regions' : regions,
            'services' : services,
            'network_border_groups' : network_border_groups,
        }
        return values

if __name__ == "__main__":
    parser = argparse.ArgumentParser(description='Get prefix list IPs from particular AWS region.')
    parser.add_argument("--region", type=str)
    parser.add_argument("--type", type=str, default="ipv4")
    args = parser.parse_args()
    iprange = IpRanges(region=args.region, type=args.type)
    print(iprange.getValues()['ip_prefixes'])