"""Methods for retrieving Ingestion Feed status from DynamoDB."""

import boto3
from boto3.dynamodb.conditions import Key

from feed_status import config

dynamodb = boto3.resource('dynamodb', region_name=config.AWS_REGION)
FEED_INGESTION_TABLE = dynamodb.Table(config.FEED_INGESTION_TABLE)


def get_ingestion_history(feed_name, from_date, to_date):
    """Look up feed status in DynamoDB.

    Args:
        feed_name (str): feed name of interest.
        from_date (date): start date of interest.
        to_date (date): end date of interest.

    Returns:
        list: list of statuses.
    """
    response = FEED_INGESTION_TABLE.query(
        KeyConditionExpression=Key('feed_name').eq(feed_name) &
        Key('date').between(from_date, to_date)
    )
    return response.get('Items')


def get_ingestion_comment(feed_id, date):
    """Look up feed status comment in DynamoDB.

    Args:
        date (str): date of interest.
        feed_id (str): feed of interest

    Returns:
        dict: comment item.
    """
    response = FEED_INGESTION_TABLE.get_item(
        Key={
            'feed_name': config.COMMENTS_FEED,
            'date': '{}.{}'.format(date, feed_id)
        },
        AttributesToGet=['date', 'comment'])
    item = response.get('Item')
    if not item:
        return False
    try:
        comment_date, feed_name = item['date'].split('.')
    except ValueError:
        return False
    comment = {
        'feed_name': feed_name,
        'date': comment_date,
        'comment': item['comment']
    }
    return comment


def save_ingestion_comment(feed_id, date, comment):
    """Save feed status comment in DynamoDB.

    Args:
        date (str): date of interest.
        feed_id (str): feed of interest

    Returns:
        dict: comment item.
    """
    response = FEED_INGESTION_TABLE.update_item(
        Key={
            'feed_name': config.COMMENTS_FEED,
            'date': '{}.{}'.format(date, feed_id),
        },
        AttributeUpdates={'comment': {
            'Value': comment
        }},
        ReturnValues='ALL_NEW')
    item = response.get('Attributes')
    if not item:
        return False
    try:
        comment_date, feed_name = item['date'].split('.')
    except ValueError:
        return False
    data = {
        'feed_name': feed_name,
        'date': comment_date,
        'comment': item['comment']
    }
    return data


def delete_ingestion_comment(feed_id, date):
    """Save feed status comment in DynamoDB.

    Args:
        date (str): date of interest.
        feed_id (str): feed of interest

    Returns:
        dict: item delete confirmation.
    """
    response = FEED_INGESTION_TABLE.delete_item(Key={
        'feed_name':
        config.COMMENTS_FEED,
        'date':
        '{}.{}'.format(date, feed_id),
    }, )
    if response['ResponseMetadata']['HTTPStatusCode'] != 200:
        return False
    return {'details': 'item was successfully deleted'}


def get_ingestion_comment_list(date):
    """Get all feed status comments for the period.

    Args:
        date (str): start date of interest

    Returns:
        list: list of comments.
    """
    response = FEED_INGESTION_TABLE.query(
        KeyConditionExpression=Key('feed_name').eq('__comments__') &
        Key('date').gt(date)
    )
    items = response.get('Items')
    comments = {}
    for item in items:
        try:
            comment_date, feed_name = item['date'].split('.')
        except ValueError:
            continue
        if feed_name not in comments.keys():
            comments[feed_name] = {comment_date: item['comment']}
        else:
            comments[feed_name][comment_date] = item['comment']
    return comments