import os
import boto3
import random
import uuid
import json
from datetime import datetime

class backend:

    def __init__(self):
        self.locale = "en-US"
        
        self.snsClient = boto3.client('sns')
        
        self.connectClient = boto3.client('connect')
        self.connectContactFlow = os.environ['CONNECT_CONTACT_FLOW_ID']
        self.connectInstanceId = os.environ['CONNECT_INSTANCE_ID']
        self.connectQueueId = os.environ['CONNECT_QUEUE_ID']
        
        self.skill_name = os.environ['SKILL_NAME']
        self.sns_topic_arn = os.environ['SNS_TOPIC_ARN']
        self.currency_code = os.environ['CURRENCY_CODE']
        
        self.enable_omnichannel_integration = bool(os.environ['ENABLE_OMNICHANNEL_INTEGRATION'])
 
        dynamodbClient = boto3.resource("dynamodb", region_name=os.environ['AWS_REGION'])
        self.tableCustomer = dynamodbClient.Table(os.environ['CUSTOMER_TABLE_NAME'])
        self.tableEvents = dynamodbClient.Table(os.environ['EVENT_TABLE_NAME'])
        self.tableOffices = dynamodbClient.Table(os.environ['OFFICE_TABLE_NAME'])
        self.tableLocalization = dynamodbClient.Table(os.environ['LOCALIZATION_TABLE_NAME'])
        
    def getLocalizedMessage(self, messageId):
        response = self.tableLocalization.get_item(Key={"messageId": messageId, "locale": self.locale})
        return response["Item"]["message"]
    
    def generateRandomPin(self):
        return random.randrange(1000, 9999)
    
    def getOfficeData(self, officeName):
        response = self.tableOffices.get_item(Key={"name": officeName})
        return response      
    
    def removePin(self, customerId):
        responseDynamo = self.tableCustomer.update_item(
                Key={
                    'Id': customerId
                    },
                UpdateExpression='REMOVE Pin'
            )

    def getPin(self, customerId):
        pin = self.generateRandomPin()

        responseDynamo = self.tableCustomer.update_item(
                Key={
                    'Id': customerId
                    },
                UpdateExpression='SET Pin=:p',
                ExpressionAttributeValues={
                    ':p': pin
                }
            )

        responseSns = self.snsClient.publish(
            TopicArn = self.sns_topic_arn,    
            Message = "Your " + self.skill_name + " PIN is: " + str(pin),  
            Subject = "Your " + self.skill_name + " PIN"  
        )    
        
        output = self.getLocalizedMessage("PIN_SENT")

        return output
    
        
    def isValidPin(self, customerId, pin):
        data = self.getCustomerData(customerId)
    
        if "Pin" not in data["Item"]:
            return False
            
        if str(data["Item"]["Pin"]) == pin:
            return True
        else:
            return False
            
    def welcomeMessage(self, customerId):
        data = self.getCustomerData(customerId)
        if data["Item"] is None:
            output = self.getLocalizedMessage("NOT_FOUND")
        else: 
            name = str(data["Item"]["FirstName"])
            output = self.getLocalizedMessage("WELCOME").format(name) + " " + self.getLocalizedMessage("HELP") + " " + self.getLocalizedMessage("PIN_PROMPT")
        
        return output    
        
    def getSavingsAccount(self, customerId, pin):
        if self.isValidPin(customerId, pin) == True:
            data = self.getCustomerData(customerId)
            if data["Item"] is None:
                output = self.getLocalizedMessage("NOT_FOUD")
            else: 
                balance = str(data["Item"]["Balance"])
                output = self.getLocalizedMessage("SAVINGS_ACCT_BALANCE").format(self.currency_code, balance)
        else:
            output = self.getLocalizedMessage("INVALID_PIN")

        return output
        
    def getCustomerData(self, customerId):
        response = self.tableCustomer.get_item(Key={"Id": customerId})
        return response
        
    def getCreditCard(self, customerId, pin):
        if self.isValidPin(customerId, pin) == True:
            data = self.getCustomerData(customerId)
            if data["Item"] is None:
                output = self.getLocalizedMessage("NOT_FOUD")
            else: 
                balance = data["Item"]["BalanceCredit"]
                limit = data["Item"]["CreditLimit"]
                dueDate = data["Item"]["PaymentDueDate"]
                output = self.getLocalizedMessage("CREDIT_CARD_BALANCE").format(self.currency_code, str(balance), self.currency_code, str(limit - balance), dueDate) 
        else:
            output = self.getLocalizedMessage("INVALID_PIN")
    
        return output
        
    def payCreditCard(self, customerId, pin, paymentAmount):
        if self.isValidPin(customerId, pin) == True:
            responseDynamo = self.tableCustomer.update_item(
                    Key={
                        'Id': customerId
                        },    
                    UpdateExpression="SET #Balance = #Balance - :amount, #BalanceCredit = #BalanceCredit - :amount",
                    ExpressionAttributeNames={
                        "#Balance": "Balance",
                        "#BalanceCredit": "BalanceCredit"
                    },
                    ExpressionAttributeValues={
                        ":amount": paymentAmount
                    },
                    ReturnValues="UPDATED_NEW"
                )
    
            output = self.getLocalizedMessage("CREDIT_CARD_PAYMENT").format(self.currency_code, paymentAmount)
        else:
            output = self.getLocalizedMessage("INVALID_PIN")
    
        return output
        
    def makeCreditAdvance(self, customerId, pin, requestedAmount):
        if self.isValidPin(customerId, pin) == True:
            responseDynamo = self.tableCustomer.update_item(
                    Key={
                        'Id': customerId
                        },    
                    UpdateExpression="SET #Balance = #Balance + :amount, #BalanceCredit = #BalanceCredit + :amount",
                    ExpressionAttributeNames={
                        "#Balance": "Balance",
                        "#BalanceCredit": "BalanceCredit"
                    },
                    ExpressionAttributeValues={
                        ":amount": requestedAmount
                    },
                    ReturnValues="UPDATED_NEW"
                )
    
            output = self.getLocalizedMessage("CREDIT_ADVANCE").format(self.currency_code, requestedAmount)
        else:
            output = self.getLocalizedMessage("INVALID_PIN")

        return output

    def getOfficeSchedule(self, officeName):
        data = self.getOfficeData(officeName)
        if not "Item" in data:
            output = self.getLocalizedMessage("NOT FOUND")
        else: 
            output = self.getLocalizedMessage("OFFICE_SCHEDULE").format(officeName, str(data["Item"]["horario"]))
    
        return output
        
    def requestCall(self, customerId):
        if self.enable_omnichannel_integration == False:
            return "This feature is not enabled"
        
        data = self.getCustomerData(customerId)
        if data["Item"] is None:
            speech_output = NOT_FOUND_MESSAGE
        else: 
            phone = data["Item"]["Phone"]
        
        response = self.connectClient.start_outbound_voice_contact(
            DestinationPhoneNumber=phone,
            ContactFlowId=self.connectContactFlow,
            InstanceId=self.connectInstanceId,
            QueueId=self.connectQueueId
            )
            
        output = self.getLocalizedMessage("CALL_REQUESTED")
    
        return output
        
    def logInteraction(self, customerId, intentName, botResponse):
        if self.enable_omnichannel_integration == True:   
            if customerId is None:
                customerId = "0000000000"

            response = self.tableEvents.put_item(
                        Item={
                            'customerId':customerId,
                            'interactionDateTime': datetime.now().isoformat(),
                            'interactionId': uuid.uuid1().hex,
                            'intentName': intentName,
                            'botName': self.skill_name,
                            'slots': intentName,
                            'message': intentName,
                            'botResponse': botResponse
                            })