import json
import boto3
from datetime import date
import time
from botocore.exceptions import ClientError
#from boto3.dynamodb.types import TypeDeserializer

def lambda_handler(event, context):
    
    try:
        
        p               = json.loads(event['body'])
        table           = "dyndata"
        partition_key   = p['datatype']
        date1           = date.fromisoformat(p['startdate'])
        date2           = date.fromisoformat(p['enddate'])
        sort_key1       = str(round(time.mktime(date1.timetuple())))
        sort_key2       = str(round(time.mktime(date2.timetuple())))
        response        = []
        dynamodb_client = boto3.client('dynamodb', region_name="ap-southeast-2")
        
        rows = dynamodb_client.query(
            TableName=table,
            Limit=6,
            KeyConditionExpression='datapart = :datapart AND datasort BETWEEN :datasort1 AND :datasort2',
            ExpressionAttributeValues={
                ':datapart': {'S': partition_key},
                ':datasort1': {'N': sort_key1},
                ':datasort2': {'N': sort_key2}
            }
        )
        
        if len(rows) > 0:
            for item in rows['Items']:
                response.append({"date": item['datasort']['N'], "datavalue": item['datavalue']['S']})
                    
        else:
            response.append({"date": "0", "datavalue": "No data found"})

    except ClientError as e:
        
        text = { "result": 1, "msg": e.response['Error']['Message'] }
        
    else:

        if len(response) == 0:
            response.append({"date": "0", "datavalue": "No data found"})
            
        text = { "result": 0, "data": response }

    return {
        "statusCode": 200,
        "isBase64Encoded": False,
        "headers": {"Access-Control-Allow-Origin" : "*"},
        "body": json.dumps(text),
    }