import json

import requests
from dynaconf import Dynaconf, Validator
from mongoengine import connect


class AppConfig:
    def __init__(self):
        self.config = Dynaconf(settings_files=[
            "/app/configs/main.json",
            "/app/configs/application_credentials.json",
            "/app/configs/db.json",
            "/app/configs/sources.json"
        ])
        self.config.validators.register(
            Validator('db', 'db.host', 'db.database', must_exist=True),
        )
        self.config.validators.validate()

        creds = self.get_db_config()
        connect(
            db=creds.database,
            host="mongodb://{host}:27017/{database}".format(host=creds.host, database=creds.database)
        )

    def get_bulk_insert_limit(self):
        if not self.config.bulk_limit:
            return 1
        else:
            return self.config.bulk_limit

    def get_db_config(self):
        return self.config.db

    def get_main_app_creds(self):
        return self.config.application_credentials

    def get_source_by_name(self, name: str):
        if name not in self.config.sources:
            raise ValueError(f'"{name}" source not exists!')
        return self.config.sources[name]

    def get_sources_list(self):
        return self.config.sources.keys()

    def update_sources(self):
        creds = self.get_main_app_creds()
        headers = {
            'Content-type': 'application/json',
            'Authorization': 'Bearer {key}'.format(key=creds.api_key)
        }
        r = requests.get(creds.api_url + "sources", headers=headers)
        if r.status_code != 200:
            raise Exception('Bad app response')

        new_config = {"sources": {}}
        for source in r.json():
            new_config["sources"][source["source_name"]] = source

        with open("./configs/sources.json", "w") as outfile:
            outfile.write(json.dumps(new_config))

config = AppConfig()