"""Module provider for RcodeZero"""
from __future__ import absolute_import

import hashlib
import json
import logging

import requests

from lexicon.providers.base import Provider as BaseProvider

LOGGER = logging.getLogger(__name__)

NAMESERVER_DOMAINS = ["rcode0.net"]


def provider_parser(subparser):
    """Return the parser for this provider"""
    subparser.add_argument("--auth-token", help="specify token for authentication")


class Provider(BaseProvider):
    """Provider class for RcodeZero"""

    def __init__(self, config):
        super(Provider, self).__init__(config)
        self.domain_id = None
        self._zone_data = None
        self.api_endpoint = "https://my.rcodezero.at/api/v1"

    def _authenticate(self):
        if self._zone_data is None:
            self._zone_data = self._get("/zones/" + self.domain)

        self.domain_id = self.domain

    # Create record.

    def _create_record(self, rtype, name, content):
        rname = self._fqdn_name(name)
        newcontent = self._clean_content(rtype, content)

        updated_data = {
            "name": rname,
            "type": rtype,
            "records": [],
            "ttl": self._get_lexicon_option("ttl") or 600,
            "changetype": "ADD",
        }

        updated_data["records"].append({"content": newcontent, "disabled": False})

        payload = self._get("/zones/{0}/rrsets?page_size=-1".format(self.domain_id))

        for rrset in payload["data"]:
            if rrset["name"] == rname and rrset["type"] == rtype:
                updated_data["ttl"] = rrset["ttl"]

                for record in rrset["records"]:
                    if record["content"] != newcontent:
                        updated_data["records"].append(
                            {
                                "content": record["content"],
                                "disabled": record["disabled"],
                            }
                        )
                    updated_data["changetype"] = "UPDATE"
                break

        request = [updated_data]
        LOGGER.debug("request: %s", request)

        self._patch("/zones/" + self.domain + "/rrsets", data=request)
        return True

    # List all records. Return an empty list if no records found
    # type, name and content are used to filter records.
    # If possible filter during the query, otherwise filter after response is received.
    def _list_records(self, rtype=None, name=None, content=None):
        filter_obj = {"per_page": 100}
        if rtype:
            filter_obj["type"] = rtype
        if name:
            filter_obj["name"] = self._full_name(name)
        if content:
            filter_obj["content"] = content

        payload = self._get("/zones/{0}/rrsets?page_size=-1".format(self.domain_id))

        records = []
        for rrset in payload["data"]:
            if (
                name is None or self._fqdn_name(rrset["name"]) == self._fqdn_name(name)
            ) and (rtype is None or rrset["type"] == rtype):
                for record in rrset["records"]:
                    if content is None or record["content"] == self._clean_content(
                        rtype, content
                    ):
                        # rcode0 does not have a record id, so lets create one
                        processed_record = {
                            "type": rrset["type"],
                            "name": self._full_name(rrset["name"]),
                            "ttl": rrset["ttl"],
                            "content": self._unclean_content(
                                rrset["type"], record["content"]
                            ),
                            "id": self._make_identifier(
                                rrset["type"], rrset["name"], record["content"]
                            ),
                        }
                        records.append(processed_record)

        LOGGER.debug("list_records: %s", records)
        return records

    def _update_record(self, identifier, rtype=None, name=None, content=None):
        self._delete_record(identifier, rtype, name, None)
        return self._create_record(rtype, name, content)

    # Delete an existing record.
    # If record does not exist, do nothing.
    def _delete_record(self, identifier=None, rtype=None, name=None, content=None):

        LOGGER.debug("delete %s %s %s %s", identifier, rtype, name, content)
        if identifier is None and (rtype is None or name is None):
            raise Exception("Must specify at least id or  both rtype and name")

        payload = self._get("/zones/{0}/rrsets?page_size=-1".format(self.domain_id))

        if identifier is not None:
            rtype, name, content = self._parse_identifier(identifier, payload)

        update_data = None
        for rrset in payload["data"]:
            if rrset["type"] == rtype and self._fqdn_name(
                rrset["name"]
            ) == self._fqdn_name(name):
                update_data = rrset

                if content is None:
                    update_data["records"] = []
                    update_data["changetype"] = "DELETE"
                else:
                    new_record_list = []
                    for record in update_data["records"]:
                        if (
                            self._clean_content(rrset["type"], content)
                            != record["content"]
                        ):
                            new_record_list.append(record)

                    update_data["records"] = new_record_list
                    if new_record_list:
                        update_data["changetype"] = "UPDATE"
                    else:
                        update_data["changetype"] = "DELETE"
                break

        if update_data is not None:
            request = [update_data]
            LOGGER.debug("request: %s", request)
            self._patch("/zones/" + self.domain + "/rrsets", data=request)

        return True

    # Helpers
    def _request(self, action="GET", url="/", data=None, query_params=None):
        if data is None:
            data = {}
        if query_params is None:
            query_params = {}
        response = requests.request(
            action,
            self.api_endpoint + url,
            params=query_params,
            data=json.dumps(data),
            headers={
                "Authorization": "Bearer " + self._get_provider_option("auth_token"),
                "Content-Type": "application/json",
                "Accept": "application/json",
            },
        )
        # if the request fails for any reason, throw an error.
        if response.status_code >= 400:
            LOGGER.debug("Bad Request: %s", response.text)
        response.raise_for_status()
        return response.json()

    # generate a unique id for a give record
    def _make_identifier(self, rtype, name, content):
        sha256 = hashlib.sha256()
        sha256.update(("type=" + rtype + ",").encode("utf-8"))
        sha256.update(("name=" + name + ",").encode("utf-8"))
        sha256.update(("content=" + content + ",").encode("utf-8"))
        return sha256.hexdigest()[0:7]

    def _parse_identifier(self, identifier, payload):

        for rrset in payload["data"]:
            for record in rrset["records"]:
                if (
                    self._make_identifier(
                        rrset["type"], rrset["name"], record["content"]
                    )
                    == identifier
                ):
                    rtype = rrset["type"]
                    name = self._full_name(rrset["name"])
                    content = self._unclean_content(rrset["type"], record["content"])
                    return rtype, name, content

        raise Exception("Record with ID {} not found ".format(identifier))

    def _clean_content(self, rtype, content):
        if rtype in ("TXT", "LOC"):
            if content[0] != '"':
                content = '"' + content
            if content[-1] != '"':
                content += '"'
        elif rtype == "CNAME":
            content = self._fqdn_name(content)
        return content

    def _unclean_content(self, rtype, content):
        if rtype in ("TXT", "LOC"):
            content = content.strip('"')
        elif rtype == "CNAME":
            content = self._full_name(content)
        return content
