import boto3

from boto3.dynamodb.conditions import Key, Attr

import config

dynamodb = boto3.resource('dynamodb')
table = dynamodb.Table(config.TABLE_NAME)

def get_isrc(label_id, isrc):
    """Get isrc from dynamodb mobile metadata."""

    isrc_key = _isrc_key_generator(label_id, isrc)

    response = table.query(
        KeyConditionExpression=Key('first_id').eq(isrc_key))

    if response.get('Count') == 1:
        return response.get('Items')[0]

    return 'could not find item'


def get_products_isrc_found_on(label_id, isrc):
    """Get product from dynamodb mobile metadata."""

    isrc_key = _isrc_key_generator(label_id, isrc)

    response = table.query(
        IndexName='second_id-first_id',
        KeyConditionExpression=Key('second_id').eq(isrc_key),
        FilterExpression=Attr('artist_name').not_exists())


    if response.get('Count') > 0:
        return response.get('Items')
    return 'could not find item'


#TO DO Handle for sub
def _isrc_key_generator(label_id, isrc):
    return 'label:{}:isrc:{}'.format(label_id, isrc)


def get_product(label_id, product_id):
    """Get product from dynamodb mobile metadata."""

    product_key = _product_key_generator(label_id, product_id)

    response = table.query(
        KeyConditionExpression=Key('first_id').eq(product_key),
        FilterExpression=Attr('artist_name').exists())

    if response.get('Count') == 1:
        return response.get('Items')[0]
    return 'could not find item'


def get_isrcs_on_product(label_id, product_id):
    """Get product from dynamodb mobile metadata."""

    product_key = _product_key_generator(label_id, product_id)

    response = table.query(
        KeyConditionExpression=Key('first_id').eq(product_key),
        FilterExpression=Attr('artist_name').not_exists())

    if response.get('Count') > 0:
        return response.get('Items')
    return 'could not find item'


#TO DO Handle for sub
def _product_key_generator(label_id, product_id):
    return 'label:{}:product:{}'.format(label_id, product_id)