# -*- coding: utf-8 -*-
"""
Display bill for Amazon Web Services.

**WARNING: This module generate some costs on the AWS bill.
Take care about the cache_timeout to limit these fees!**

Configuration parameters:
    aws_access_key_id: Your AWS access key (default '')
    aws_account_id: The root ID of the AWS account
        Can be found here` https://console.aws.amazon.com/billing/home#/account
        (default '')
    aws_secret_access_key: Your AWS secret key (default '')
    billing_file: Csv file location (default '/tmp/.aws_billing.csv')
    cache_timeout: How often we refresh this module in seconds (default 3600)
    format: string that formats the output. See placeholders below.
        (default '{bill_amount}$')
    s3_bucket_name: The bucket where billing files are sent by AWS.
        Follow this article to activate this feature:
        https://docs.aws.amazon.com/awsaccountbilling/latest/aboutv2/billing-reports.html
        (default '')

Format placeholders:
    {bill_amount} AWS bill amount

Color options:
    color_good: Balance available
    color_bad: An error has occured

Requires:
    boto:

@author nawadanp

SAMPLE OUTPUT
{'full_text': u'108.78$'}
"""

import boto
import csv
import datetime

from boto.s3.connection import Key


class Py3status:
    """
    """
    # available configuration parameters
    aws_access_key_id = ''
    aws_account_id = ''
    aws_secret_access_key = ''
    billing_file = '/tmp/.aws_billing.csv'
    cache_timeout = 3600
    format = '{bill_amount}$'
    s3_bucket_name = ''

    def _get_bill_amount(self):
        # Billing file name, generated by Amazon itself
        # Format : 123456789012-aws-billing-csv-yyyy-mm.csv
        s3_file_key = '{}-aws-billing-csv-{}-{}.csv'.format(
            self.aws_account_id, datetime.datetime.now().strftime('%Y'),
            datetime.datetime.now().strftime('%m'))
        i = 0

        # Connection to s3 service
        try:
            conn = boto.connect_s3(self.aws_access_key_id,
                                   self.aws_secret_access_key)
        except:  # noqa e722
            return 'conn_error'

        # Connection to the bucket
        try:
            bucket = conn.get_bucket(self.s3_bucket_name)
        except:  # noqa e722
            return 'bucket_error'

        # Fetch the objects keys and get the billing file
        try:
            k = Key(bucket)
            k.key = s3_file_key
            k.get_contents_to_filename(self.billing_file)
            k.close
        except:  # noqa e722
            return 'key_error'

        # Parse the file and get the InvoiceTotal amount
        try:
            with open(self.billing_file, 'rb') as f:
                reader = csv.reader(f)
                for row in reader:
                    if ''.join(row).find('InvoiceTotal') == -1:
                        continue
                    i = i + 1
                    return row[-1]
        except:  # noqa e722
            return 'csv_error'

        return False

    def aws_bill(self):
        response = {
            'cached_until': self.py3.time_in(self.cache_timeout),
            'color': self.py3.COLOR_BAD,
            'full_text': ''
        }

        bill_amount = self._get_bill_amount()

        if bill_amount == 'csv_error':
            response['full_text'] = 'Bad CSV file'
        elif bill_amount == 'key_error':
            response['full_text'] = 'Key not found in the bucket'
        elif bill_amount == 'bucket_error':
            response['full_text'] = 'Check the bucket name or your AWS keys'
        elif bill_amount == 'conn_error':
            response['full_text'] = 'Check your internet access'
        elif bill_amount is not False:
            response['full_text'] = self.py3.safe_format(
                self.format, {'bill_amount': bill_amount}
            )
            response['color'] = self.py3.COLOR_GOOD
        else:
            response['full_text'] = 'Global error - WTF exception'

        return response


if __name__ == "__main__":
    """
    Run module in test mode.
    """
    from py3status.module_test import module_test
    module_test(Py3status)
