3. Processing Incoming Data

import json
import boto3
import urllib.request
import uuid
import time
import base64
from urllib.parse import parse_qs

s3 = boto3.client('s3')
translate = boto3.client('translate')
transcribe = boto3.client('transcribe')
lex = boto3.client('lexv2-runtime')

BUCKET_NAME = 'aws-chatbot-audio'
BOT_ID = '<YourLexBotId>' # replace with your actual Bot ID
BOT_ALIAS_ID = '<YourAliasBotId>' #   replace with your actual Bot Alias ID
LOCALE_ID = 'en_US'

def is_audio(event):
    files = event.get('files', [])
    return any(f.get('mimetype', '').startswith('audio/') for f in files)

def download_audio_file(url, headers):
    req = urllib.request.Request(url, headers=headers)
    return urllib.request.urlopen(req).read()

def upload_to_s3(data, key):
    s3.put_object(Bucket=BUCKET_NAME, Key=key, Body=data)
    return f's3://{BUCKET_NAME}/{key}'

def start_transcribe(s3_uri):
    job = f"job-{uuid.uuid4()}"
    transcribe.start_transcription_job(
        TranscriptionJobName=job,
        Media={'MediaFileUri': s3_uri},
        MediaFormat='mp3',
        LanguageCode='en-US',
        OutputBucketName=BUCKET_NAME
    )
    return job

def poll_transcribe(job, timeout=30):
    elapsed = 0
    while elapsed < timeout:
        res = transcribe.get_transcription_job(TranscriptionJobName=job)
        status = res['TranscriptionJob']['TranscriptionJobStatus']
        if status == 'COMPLETED':
            return res['TranscriptionJob']['Transcript']['TranscriptFileUri']
        elif status == 'FAILED':
            raise Exception("Transcribe job failed")
        time.sleep(3)
        elapsed += 3
    raise TimeoutError("Transcribe job timed out")

def fetch_text(uri):
    with urllib.request.urlopen(uri) as r:
        return json.loads(r.read())['results']['transcripts'][0]['transcript']

def send_to_lex(text, session_id):
    res = lex.recognize_text(
        botId=BOT_ID,
        botAliasId=BOT_ALIAS_ID,
        localeId=LOCALE_ID,
        sessionId=session_id,
        text=text
    )
    return res['messages'][0]['content'] if res.get('messages') else "No reply from Lex."

def lambda_handler(event, context):
    print("Incoming event:", event)
    
    # Handle Slack URL verification challenge
    if 'body' in event:
        body_str = event['body']
        if event.get('isBase64Encoded', False):
            body_str = base64.b64decode(body_str).decode('utf-8')
        
        try:
            # Try to parse as JSON first (for Slack events)
            body_json = json.loads(body_str)
            if body_json.get('type') == 'url_verification':
                print("Handling Slack URL verification challenge")
                return {
                    'statusCode': 200,
                    'body': body_json.get('challenge', ''),
                    'headers': {'Content-Type': 'text/plain'}
                }
        except json.JSONDecodeError:
            # If not JSON, continue with existing logic (form data)
            pass
    
    text = ""

    if 'body' in event and 'headers' in event:
        body_str = event['body']
        if event.get('isBase64Encoded', False):
            body_str = base64.b64decode(body_str).decode('utf-8')
            print(f"Decoded body: {body_str}")
        
        # Try to parse as form data (for slash commands)
        try:
            body = parse_qs(body_str)
            text = body.get('text', [''])[0].strip()
            print("Input type: TEXT (via Slack slash command)")
            print(f"Received text: '{text}'")
        except:
            print("Could not parse as form data")

    if not text or not text.strip():
        return {
            'statusCode': 200,
            'body': json.dumps({
                'text': 'Please provide some text.',
                'response_type': 'ephemeral'
            }),
            'headers': {'Content-Type': 'application/json'}
        }

    # Translate text to English if needed
    original_language = 'en'
    english_text = text  # Default initialization

    try:
        translate_result = translate.translate_text(
            Text=text,
            SourceLanguageCode='auto',
            TargetLanguageCode='en'
        )
        original_language = translate_result['SourceLanguageCode']
        english_text = translate_result['TranslatedText']
        print(f"Detected language: {original_language}")
        print(f"Translated to English: '{english_text}'")
    except Exception as e:
        print(f"Translation error: {e}")
        original_language = 'en'
        english_text = text  # Fallback to original text

    print("Sending text to Lex...")
    lex_msg = send_to_lex(english_text, session_id="test-session-123")  
    print(f"Lex replied: {lex_msg}")

    return {
        'statusCode': 200,
        'body': json.dumps({
            'text': lex_msg,
            'response_type': 'in_channel'
        }),
        'headers': {'Content-Type': 'application/json'}
    }