# this function takes in "input_string" and return the sha256 hash of that string

import json
import hashlib

def lambda_handler(event, context):
    # Get input_string from query params, body, or path
    input_string = None

    # Try query parameters first
    if 'queryStringParameters' in event and event['queryStringParameters']:
        input_string = event['queryStringParameters'].get('input_string')

    # Try request body
    if not input_string and 'body' in event:
        try:
            body = json.loads(event['body']) if isinstance(event['body'], str) else event['body']
            input_string = body.get('input_string')
        except:
            input_string = event['body']

    # Try path parameter as fallback
    if not input_string and 'pathParameters' in event:
        input_string = event['pathParameters'].get('input_string', event['pathParameters'].get('proxy'))

    if not input_string:
        return {
            'statusCode': 400,
            'headers': {'Content-Type': 'application/json'},
            'body': json.dumps({'error': 'input_string required'})
        }

    # Calculate SHA256
    sha256_hash = hashlib.sha256(input_string.encode('utf-8')).hexdigest()

    return {
        'statusCode': 200,
        'headers': {
            'Content-Type': 'application/json'
        },
        'body': json.dumps({
            'input_string': input_string,
            'sha256': sha256_hash
        })
    }