import json
import os
import boto3

from datetime import datetime, timezone
from decimal import Decimal

now = datetime.utcnow()
dynamodb = boto3.resource("dynamodb")
table = dynamodb.Table("cctv-people-analytics-table")
region = "eu-west-1"  

from opensearchpy import OpenSearch, RequestsHttpConnection, AWSV4SignerAuth
from requests_aws4auth import AWS4Auth

service = 'aoss'
credentials = boto3.Session().get_credentials().get_frozen_credentials()
print(credentials.access_key, credentials.secret_key, credentials.token)

auth = AWSV4SignerAuth(credentials, region, service)

auth = AWS4Auth(
    credentials.access_key,
    credentials.secret_key,
    region,
    service,
    session_token=credentials.token  # ✅ include session token!
)

host = "5xmv01a4621tqq8agz99.eu-west-1.aoss.amazonaws.com"
index = now.strftime("cctv-people-analytics-%Y-%m-%d-%H")
url = f"{host}/{index}/_doc"

client = OpenSearch(
    hosts=[{'host': host, 'port': 443}],
    http_auth=auth,
    use_ssl=True,
    verify_certs=True,
    connection_class=RequestsHttpConnection,
    pool_maxsize=20,
)

if not client.indices.exists(index=index):
    client.indices.create(index=index)

def normalize_timestamp(ts: str) -> str:
    """
    Normalize timestamp into ISO 8601 with UTC (Z).
    Handles:
      - %Y-%m-%dT%H-%M-%S   (bad format with dashes)
      - %Y-%m-%dT%H:%M:%S   (already correct)
      - Epoch numbers (int/float)
    """
    if isinstance(ts, (int, float)):  # epoch
        return datetime.fromtimestamp(ts/1000, tz=timezone.utc).isoformat().replace("+00:00", "Z")

    if isinstance(ts, str):
        # Already ISO with colons
        try:
            dt = datetime.strptime(ts, "%Y-%m-%dT%H:%M:%S")
            return dt.replace(tzinfo=timezone.utc).isoformat().replace("+00:00", "Z")
        except ValueError:
            pass

        # Bad format with dashes
        try:
            dt = datetime.strptime(ts, "%Y-%m-%dT%H-%M-%S")
            return dt.replace(tzinfo=timezone.utc).isoformat().replace("+00:00", "Z")
        except ValueError:
            pass

    # Fallback: return as-is
    return str(ts)

def epoch_converter(ts):
    """
    Normalize timestamp into epoch milliseconds (integer).
    """
    if isinstance(ts, (int, float)):
        # already epoch
        return int(ts)
    if isinstance(ts, str):
        try:
            # Try ISO format
            dt = datetime.strptime(ts, "%Y-%m-%dT%H:%M:%S")
        except ValueError:
            # Bad format with dashes
            dt = datetime.strptime(ts, "%Y-%m-%dT%H-%M-%S")
        # Convert to UTC epoch milliseconds
        dt = dt.replace(tzinfo=timezone.utc)
        return int(dt.timestamp() * 1000)
    return int(ts)  # fallback

def lambda_handler(event, context):
    print(event)
    dict_stream_camid = {
        'CCTV-Stream': 'iMbYu7fVoHRP',
        'TAPO-C246D-Stream': 'piYD7HWDKAub',
        'TAPO-C500-Stream': 'EZ4DnbJjqFvk',
        'HIKVision-2MP-Dome-1-Stream': 'x4j8eVyrF6mO',
        'HIKVision-2MP-Dome-2-Stream': 'NnIXfhJeqX6i',
        'HIKVision-2MP-Bullet-1-Stream': 'vP2wVuCEN5vi',
        'HIKVision-2MP-Bullet-2-Stream': 'SnPNqUVLHinu',
        'Dahua-2MP-Dome-1-Stream': 'YMpY5kku8IXg',
        'Dahua-2MP-Dome-2-Stream': 'yyzi5SqLTftn',
        'Dahua-2MP-Bullet-1-Stream': 'YTOYlpGjviLB',
        'Dahua-2MP-Bullet-2-Stream': 'cLVBa3vAV4yf'
    }

    notification = json.loads(event['Records'][0]['Sns']['Message'])
    if notification['eventNamespace']['type'] == 'LABEL_DETECTED':
        stream_arn = notification['inputInformation']['kinesisVideo']['streamArn']
        camera_id = dict_stream_camid[stream_arn.split('/')[1]]
    
        for label in notification['labels']:
            label_id = label['id']
            detect_timestamp = datetime.now().strftime('%Y-%m-%dT%H:%M:%S')
            frame_timestamp = label['videoMapping']['kinesisVideoMapping']['serverTimestamp']
            frame_url = str.replace(label['frameImageUri'], 's3://cctv-stream-results/', 'https://cctv-stream-results.s3.eu-west-1.amazonaws.com/')
            label_name = label['name']
            confidence = label['confidence']
            
            to_upload_dynamodb = {
                'camera_id': camera_id,
                'label_id': label_id,
                'detect_timestamp': normalize_timestamp(detect_timestamp),
                'frame_timestamp': normalize_timestamp(frame_timestamp),
                'frame_url': frame_url,
                'label_name': label_name,
                'confidence': Decimal(str(confidence)),
                'rekognition_response': json.dumps(label)
            }
            print()
            response= table.put_item(Item=to_upload_dynamodb)
            if response['ResponseMetadata']['HTTPStatusCode'] == 200:
                print("Item successfully written!")

            # headers = { "Content-Type": "application/json" }
            # response = requests.post(url, auth=awsauth, json=to_upload, headers=headers)
            # print(response.text, response.status_code)
            to_upload_es = {
                'label_id': label_id,
                '@timestamp': normalize_timestamp(detect_timestamp),
                'frame_timestamp': normalize_timestamp(frame_timestamp),
                'frame_url': frame_url,
                'label_name': label_name,
                'confidence': Decimal(str(confidence))
            }

            ####
            response = client.index(
            index = index,
            body = to_upload_es
            )
            print(response)
    
    return {
        'statusCode': 200,
        'body': json.dumps('Processing cctv results success'),
    }