"""Shared utilities helpers."""

from datetime import datetime
from functools import wraps
import hashlib
from time import time
from flask import g
from flask import request

from oto import response
from oto.adaptors.flask import flaskify
from werkzeug.exceptions import BadRequest

from prs import config
from prs.constants import error


def get_file_code():
    """Generate 5 character code for file names.

    Returns:
        string: a randomly generated 5 character code, used in generating
            unique file names.
    """
    return hashlib.md5(str(time()).encode('utf-8')).hexdigest()[:5].upper()


def generate_file_base_name(tool_name, country_name, file_code):
    """Generate file base name.

    Args:
        tool_name (str): Used to create a folder w.r.t tool_name.
        country_name (str): Country name
        file_code (str): 5 character file code

    Returns:
        string: File base name
    """
    current_date_time = get_current_datetime('%Y-%m-%d-%I.%M.%S%p').lower()
    file_base_name = '{}/{}/{}-{}-{}'.format(
        config.SERVICE_NAME, tool_name, country_name.replace(' ', '_'),
        file_code, current_date_time)

    return file_base_name


def get_current_datetime(datetime_format):
    """Get current datetime in string as per given format.

    Args:
        datetime_format (str): datetime format as required by strftime function

    Returns:
        string: Current datetime
    """
    return datetime.now().strftime(datetime_format)


def log_info_to_loggly(message):
    """Log message to Loggly as info.

    Args:
        message (str): message to be logged in Loggly
    """
    g.ows.log.info(message)


def validate_request_json(function):
    """Decorator to validate json request.

    Returns:
        func: function decorated with error-handling logic
    """
    @wraps(function)
    def validate_json(*args, **kwargs):
        valid_request_json = True
        try:
            tool_param_data = request.get_json()
            if not isinstance(tool_param_data, dict) or not tool_param_data:
                valid_request_json = False
        except BadRequest:
                valid_request_json = False

        if not valid_request_json:
            return flaskify(response.create_error_response(
                code=error.ERROR_CODE_BAD_REQUEST,
                message=error.ERROR_MESSAGE_INVALID_REQUEST_BODY))

        return function(*args, **kwargs)
    return validate_json