import os
import time
import json
import boto3
import logging
from datetime import date, datetime
from botocore.client import Config

# Load environment variables
sma_id = os.environ["SMA_ID"]
forwarding_table_name = os.environ["CallForwardingTableName"]

# Setup DynamoDB & Chime interface clients
client_config = Config(connect_timeout=2, read_timeout=2, retries={"max_attempts": 5})
dynamodb_client = boto3.client("dynamodb", config=client_config, region_name=os.environ["AWS_REGION"])
chime_client = boto3.client("chime", config=client_config, region_name=os.environ["AWS_REGION"])

# Set LogLevel using environment variable, fallback to INFO if not present
logger = logging.getLogger()
try:
    log_level = os.environ["LogLevel"]
    if log_level not in ["INFO", "DEBUG"]:
        log_level = "INFO"
except:
    log_level = "INFO"
logger.setLevel(log_level)


# Lambda entry point for all event types
def lambda_handler(event, context):
    method = event["resource"][1::]
    logger.info("[{}] event invoked with body: {}".format(method, event["body"]))

    response = {
        "statusCode": "200",
        "body": "",
        "headers": {
            "Access-Control-Allow-Origin": "*",
            "Access-Control-Allow-Methods": "OPTIONS, POST",
            "Content-Type": "application/json",
        },
    }

    if method == "queryNumber":
        response["body"] = json.dumps(chime_client.list_phone_numbers(), default=json_serial)

    elif method == "listVoiceConnectors":
        response["body"] = json.dumps(chime_client.list_voice_connectors(), default=json_serial)

    elif method == "updateNumber":
        body = json.loads(event["body"])
        queried_number = chime_client.get_phone_number(PhoneNumberId=body["PhoneNumber"])
        if body["ProductType"] == "SipMediaApplicationDialIn":
            response["statusCode"], response["body"] = enable_forward(body, queried_number)

        elif body["ProductType"] == "VoiceConnector":
            response["statusCode"], response["body"] = disable_forward(body, queried_number)
        else:
            response["body"] = "Unknown ProductType: " + body["ProductType"]

    else:
        response["body"] = "Not Found"
        response["statusCode"] = "404"

    logger.info("Responding with: {} {}".format(response["statusCode"], response["body"]))
    logger.info(response)
    return response


def json_serial(data):
    if isinstance(data, (datetime, date)):
        return data.isoformat()
    raise TypeError("Type %s not serializable" % type(data))


def enable_forward(body, queried_number):
    logger.info("Enabling forward for {} to {}".format(body["PhoneNumber"], body["ForwardToNumber"]))
    if not ddb_add_forward(body["PhoneNumber"], body["ForwardToNumber"]):
        return "500", json.dumps("Failed to enable number forward", default=json_serial)
    if (
        queried_number["PhoneNumber"]["ProductType"] == "SipMediaApplicationDialIn"
        and queried_number["PhoneNumber"]["Status"] == "Assigned"
    ):
        return "200", json.dumps({"Message": "ProductType already SMA"}, default=json_serial)
    else:
        return "200", json.dumps(assign_number_to_SMA(queried_number), default=json_serial)


def disable_forward(body, queried_number):
    logger.info("Disabling forward for {}".format(body["PhoneNumber"]))
    if not ddb_remove_forward(body["PhoneNumber"]):
        return "500", json.dumps("Failed to disable number forward", default=json_serial)

    if queried_number["PhoneNumber"]["ProductType"] == "VoiceConnector":
        return "200", json.dumps(
            "{} is already a Voice Connector product type".format(body["PhoneNumber"]), default=json_serial
        )
    else:
        return "200", json.dumps(assign_number_to_VC(queried_number, body["VoiceConnectorId"]), default=json_serial)


# Change Product Type of number to SipMediaApplicationDialin
def assign_number_to_SMA(queried_number):
    number = queried_number["PhoneNumber"]["E164PhoneNumber"]
    logger.info("Assigning {} to SMA".format(number))

    get_sma_response = chime_client.get_sip_media_application(SipMediaApplicationId=sma_id)

    # Associate number with SMA
    if queried_number["PhoneNumber"]["ProductType"] == "VoiceConnector":
        if queried_number["PhoneNumber"]["Status"] == "Assigned":
            chime_client.disassociate_phone_numbers_from_voice_connector(
                VoiceConnectorId=queried_number["PhoneNumber"]["Associations"][0]["Value"], E164PhoneNumbers=[number]
            )

        chime_client.update_phone_number(PhoneNumberId=number, ProductType="SipMediaApplicationDialIn")

    create_sip_rule_response = chime_client.create_sip_rule(
        Name=number,
        TriggerType="ToPhoneNumber",
        TriggerValue=number,
        Disabled=False,
        TargetApplications=[
            {
                "SipMediaApplicationId": sma_id,
                "Priority": 1,
                "AwsRegion": get_sma_response["SipMediaApplication"]["AwsRegion"],
            },
        ],
    )
    return create_sip_rule_response


# Change Product Type of number to VoiceConnector
def assign_number_to_VC(queried_number, voice_connector_ID):
    number = queried_number["PhoneNumber"]["E164PhoneNumber"]
    logger.info("Assigning {} to Voice Connector {}".format(number, voice_connector_ID))

    # Disable and delete the associated SIP Rule
    if queried_number["PhoneNumber"]["Status"] == "Assigned":
        chime_client.update_sip_rule(
            SipRuleId=queried_number["PhoneNumber"]["Associations"][0]["Value"],
            Name=queried_number["PhoneNumber"]["Associations"][0]["Name"],
            Disabled=True,
        )
        chime_client.delete_sip_rule(SipRuleId=queried_number["PhoneNumber"]["Associations"][0]["Value"])

    # Wait for the status to be changed to Unassigned
    while queried_number["PhoneNumber"]["Status"] == "Assigned":
        time.sleep(2)
        queried_number = chime_client.get_phone_number(PhoneNumberId=number)

    # Set Product Type to VC
    chime_client.update_phone_number(PhoneNumberId=number, ProductType="VoiceConnector")

    # Associate number with a Voice Connector
    vc_associate_response = chime_client.associate_phone_numbers_with_voice_connector(
        VoiceConnectorId=voice_connector_ID,
        E164PhoneNumbers=[
            number,
        ],
        ForceAssociate=True,
    )
    return vc_associate_response


# Add DynamoDB entry for forwarding
def ddb_add_forward(from_number, to_number):
    try:
        response = dynamodb_client.put_item(
            Item={
                "dialed_number": {
                    "S": str(from_number),
                },
                "destination_number": {
                    "S": str(to_number),
                },
            },
            TableName=forwarding_table_name,
        )
        if response["ResponseMetadata"]["HTTPStatusCode"] == 200:
            return response
    except Exception as err:
        logger.error("DynamoDB Query error: failed to insert data into table. Error: ", exc_info=err)
        return None


# Remove DynamoDB entry for forwarding
def ddb_remove_forward(from_number):
    try:
        response = dynamodb_client.delete_item(
            Key={
                "dialed_number": {
                    "S": str(from_number),
                }
            },
            TableName=forwarding_table_name,
        )
        if response["ResponseMetadata"]["HTTPStatusCode"] == 200:
            return response
    except Exception as err:
        logger.error("DynamoDB Query error: failed to delete data from table. Error: ", exc_info=err)
        return None