import functions from './functions.js'
const { env } = process

// CONFIGURATION
// Set your API keys and edit the configuration as needed for your business use case.

// Required. Specify the SnakeChat API key to be used
// You can obtain it here: https://chat.sagi-digital.com/developers/apikeys
const apiKey = env.API_KEY || 'ENTER API KEY HERE'

// Required. Specify the OpenAI API key to be used
// You can sign up for free here: https://platform.openai.com/signup
// Obtain your API key here: https://platform.openai.com/account/api-keys
const openaiKey = env.OPENAI_API_KEY || ''

// Required. Set the OpenAI model to use.
// You can use a pre-existing model or create your fine-tuned model.
// Fastest and cheapest: gpt-4o-mini
// Recommended: gpt-4o
// List of available models: https://platform.openai.com/docs/models
const openaiModel = env.OPENAI_MODEL || 'gpt-4o'

// Ngrok tunnel authentication token.
// Required if webhook URL is not provided or running the program from your computer.
// sign up for free and get one: https://ngrok.com/signup
// Learn how to obtain the auth token: https://ngrok.com/docs/agent/#authtokens
const ngrokToken = env.NGROK_TOKEN || ''

// Default message when the user sends an unknown message.
const unknownCommandMessage = `I'm sorry, I was unable to understand your message. Can you please elaborate more?

If you would like to chat with a human, just reply with *human*.`

// Default welcome message. Change it as you need.
const welcomeMessage = 'Hey there 👋 Welcome to this ChatGPT-powered AI chatbot demo using *SnakeChat API*! I can also speak many languages 😁'

// AI bot instructions to adjust its bevarior. Change it as you need.
// Use concise and clear instructions.
const botInstructions = `You are a smart virtual customer support assistant who works for SnakeChat.
You can identify yourself as Milo, the SnakeChat AI Assistant.
You will be chatting with random customers who may contact you with general queries about the product.
SnakeChat is a cloud solution that offers WhatsApp API and multi-user live communication services designed for businesses and developers.
SnakeChat also enables customers to automate WhatsApp communication and build chatbots.
You are an expert customer support agent.
Be polite. Be helpful. Be emphatic. Be concise.
Politely reject any queries that are not related to customer support tasks or SnakeChat services itself.
Stick strictly to your role as a customer support virtual assistant for SnakeChat.
Always speak in the language the user prefers or uses.
If you can't help with something, ask the user to type *human* in order to talk with customer support.
Do not use Markdown formatted and rich text, only raw text.`

// Default help message. Change it as you need.
const defaultMessage = `Don't be shy 😁 try asking anything to the AI chatbot, using natural language!

Example queries:

1️⃣ Explain me what is SnakeChat
2️⃣ Can I use SnakeChat to send automatic messages?
3️⃣ Can I schedule messages using SnakeChat?
4️⃣ Is there a free trial available?

Type *human* to talk with a person. The chat will be assigned to an available member of the team.

Give it a try! 😁`

// Chatbot features. Edit as needed.
const features = {
  // Enable or disable text input processing
  audioInput: true,
  // Enable or disable audio voice responses.
  // By default the bot will only reply with an audio messages if the user sends an audio message first.
  audioOutput: true,
  // Reply only using audio voice messages instead of text.
  // Requires "features.audioOutput" to be true.
  audioOnly: false,
  // Audio voice to use for the bot responses. Requires "features.audioOutput" to be true.
  // Options: 'alloy', 'echo', 'fable', 'onyx', 'nova', 'shimmer'
  // More info: https://platform.openai.com/docs/guides/text-to-speech
  voice: 'echo',
  // Audio voice speed from 0.25 to 2. Requires "features.audioOutput" to be true.
  voiceSpeed: 1,
  // Enable or disable image input processing
  // Note: image processing can significnantly increase the AI token processing costs compared to text
  imageInput: true
}

// Template messages to be used by the chatbot on specific scenarios. Customize as needed.
const templateMessages = {
  // When the user sends an audio message that is not supported or transcription failed
  noAudioAccepted: 'Audio messages are not supported: gently ask the user to send text messages only.',
  // Chat assigned to a human agent
  chatAssigned: 'You will be contact shortly by someone from our team. Thank you for your patience.'
}

const limits = {
  // Required. Maximum number of characters from user inbound messages to be procesed.
  // Exceeding characters will be ignored.
  maxInputCharacters: 1000,
  // Required: maximum number of tokens to generate in AI responses.
  // The number of tokens is the length of the response text.
  // Tokens represent the smallest unit of text the model can process and generate.
  // AI model cost is primarely based on the input/output tokens.
  // Learn more about tokens: https://platform.openai.com/docs/concepts#tokens
  maxOutputTokens: 1000,
  // Required. Maximum number of messages to store in cache per user chat.
  // A higher number means higher OpenAI costs but more accurate responses thanks to more conversational context.
  // The recommendation is to keep it between 10 and 20.
  chatHistoryLimit: 20,
  // Required. Maximum number of messages that the bot can reply on a single chat.
  // This is useful to prevent abuse from users sending too many messages.
  // If the limit is reached, the chat will be automatically assigned to an agent
  // and the metadata key will be addded to the chat contact: "bot:chatgpt:status" = "too_many_messages"
  maxMessagesPerChat: 500,
  // Maximum number of messages per chat counter time window to restart the counter in seconds.
  maxMessagesPerChatCounterTime: 24 * 60 * 60,
  // Maximum input audio duration in seconds: default to 2 minutes
  // If the audio duration exceeds this limit, the message will be ignored.
  maxAudioDuration: 2 * 60,
  // Maximum image size in bytes: default to 2 MB
  // If the image size exceeds this limit, the message will be ignored.
  maxImageSize: 2 * 1024 * 1024
}

// Chatbot config
export default {
  // Required. SnakeChat API key to be used. See the `apiKey` declaration above.
  apiKey,

  // Required. Specify the OpenAI API key to be used. See the `openaiKey` declaration above.
  // You can sign up for free here: https://platform.openai.com/signup
  // Obtain your API key here: https://platform.openai.com/account/api-keys
  openaiKey,

  // Required. Set the OpenAI model to use. See the `openaiModel` declaration above.
  // You can use a pre-existing model or create your fine-tuned model.
  openaiModel,

  // Optional. Specify the SnakeChat device ID (24 characters hexadecimal length) to be used for the chatbot
  // If no device is defined, the first connected WhatsApp device will be used.
  // In case you have multiple WhatsApp number connected in your Wassenter account, you should specify the device ID to be used.
  // Obtain the device ID in the SnakeChat app: https://chat.sagi-digital.com/number
  device: env.DEVICE || 'ENTER WHATSAPP DEVICE ID',

  // Callable functions for RAG to be interpreted by the AI. Optional.
  // See: functions.js
  // Edit as needed to cover your business use cases.
  // Using it you can instruct the AI to inform you to execute arbitrary functions
  // in your code based in order to augment information for a specific user query.
  // For example, you can call an external CRM in order to retrieve, save or validate
  // specific information about the customer, such as email, phone number, user ID, etc.
  // Learn more here: https://platform.openai.com/docs/guides/function-calling
  functions,

  // Supported AI features: see features declaration above
  features,

  // Limits for the chatbot: see limits declaration above
  limits,

  // Template message responses
  templateMessages,

  // Optional. HTTP server TCP port to be used. Defaults to 8080
  port: +env.PORT || 8080,

  // Optional. Use NODE_ENV=production to run the chatbot in production mode
  production: env.NODE_ENV === 'production',

  // Optional. Specify the webhook public URL to be used for receiving webhook events
  // If no webhook is specified, the chatbot will autoamtically create an Ngrok tunnel
  // and register it as the webhook URL.
  // IMPORTANT: in order to use Ngrok tunnels, you need to sign up for free, see the option below.
  webhookUrl: env.WEBHOOK_URL,

  // Ngrok tunnel authentication token.
  // Required if webhook URL is not provided or running the program from your computer.
  // sign up for free and get one: https://ngrok.com/signup
  // Learn how to obtain the auth token: https://ngrok.com/docs/agent/#authtokens
  ngrokToken,

  // Optional. Full path to the ngrok binary.
  ngrokPath: env.NGROK_PATH,

  // Temporal files path to store audio and image files. Defaults to `.tmp/`
  tempPath: '.tmp',

  // Set one or multiple labels on chatbot-managed chats
  setLabelsOnBotChats: ['bot'],

  // Remove labels when the chat is assigned to a person
  removeLabelsAfterAssignment: true,

  // Set one or multiple labels on chatbot-managed chats
  setLabelsOnUserAssignment: ['from-bot'],

  // Optional. Set a list of labels that will tell the chatbot to skip it
  skipChatWithLabels: ['no-bot'],

  // Optional. Ignore processing messages sent by one of the following numbers
  // Important: the phone number must be in E164 format with no spaces or symbols
  // Example number: 1234567890
  numbersBlacklist: ['1234567890'],

  // Optional. OpenAI model completion inference params
  // Learn more: https://platform.openai.com/docs/api-reference/chat/create
  inferenceParams: {
    temperature: 0.2
  },

  // Optional. Only process messages one of the the given phone numbers
  // Important: the phone number must be in E164 format with no spaces or symbols
  // Example number: 1234567890
  numbersWhitelist: [],

  // Skip chats that were archived in WhatsApp
  skipArchivedChats: true,

  // If true, when the user requests to chat with a human, the bot will assign
  // the chat to a random available team member.
  // You can specify which members are eligible to be assigned using the `teamWhitelist`
  // and which should be ignored using `teamBlacklist`
  enableMemberChatAssignment: true,

  // If true, chats assigned by the bot will be only assigned to team members that are
  // currently available and online (not unavailable or offline)
  assignOnlyToOnlineMembers: false,

  // Optional. Skip specific user roles from being automatically assigned by the chat bot
  // Available roles are: 'admin', 'supervisor', 'agent'
  skipTeamRolesFromAssignment: ['admin'], // 'supervisor', 'agent'

  // Enter the team member IDs (24 characters length) that can be eligible to be assigned
  // If the array is empty, all team members except the one listed in `skipMembersForAssignment`
  // will be eligible for automatic assignment
  teamWhitelist: [],

  // Optional. Enter the team member IDs (24 characters length) that should never be automatically assigned chats to
  teamBlacklist: [],

  // Optional. Set metadata entries on bot-assigned chats
  setMetadataOnBotChats: [
    {
      key: 'bot_start',
      value: () => new Date().toISOString()
    }
  ],

  // Optional. Set metadata entries when a chat is assigned to a team member
  setMetadataOnAssignment: [
    {
      key: 'bot_stop',
      value: () => new Date().toISOString()
    }
  ],

  defaultMessage,
  botInstructions,
  welcomeMessage,
  unknownCommandMessage,

  // Do not change: specifies the base URL for the SnakeChat API
  apiBaseUrl: env.API_URL || 'https://api.sagi-digital.com/v1'
}

// Disable LanceDB logs: comment line to enable logs
env.LANCEDB_LOG = 0

// Tool functions to be consumed by the AI when needed.
// Edit as needed to cover your business use cases.
// Using it you can instruct the AI to inform you to execute arbitrary functions
// in your code based in order to augment information for a specific user query.
// For example, you can call an external CRM in order to retrieve, save or validate
// specific information about the customer, such as email, phone number, user ID, etc.
// Learn more here: https://platform.openai.com/docs/guides/function-calling
const functions = [
  // Sample function to retrieve plan prices of the product
  // Edit as needed to cover your business use cases
  {
    name: 'getPlanPrices',
    description: 'Get available plans and prices information available in SnakeChat',
    parameters: { type: 'object', properties: {} },
    // Function implementation that will be executed when the AI requires to call this function
    // The function must return a string with the information to be sent back to the AI for the response generation
    // You can also return a JSON or a prompt message instructing the AI how to respond to a user
    // Functions may be synchronous or asynchronous.
    //
    // The bot will inject the following parameters:
    // - parameters: function parameters provided by the AI when the function has parameters defined
    // - response: AI generated response object, useful to evaluate the AI response and take actions
    // - data: webhook event context, useful to access the last user message, chat and contact information
    // - device: WhatsApp number device information provided the by SnakeChat API
    // - messages: an list of previous messages in the same user chat
    run: async ({ parameters, response, data, device, messages }) => {
      // console.log('=> data:', response)
      // console.log('=> response:', response)
      const reply = [
        '*Send & Receive messages + API + Webhooks + Team Chat + Campaigns + CRM + Analytics*',
        '',
        '- Platform Professional: 30,000 messages + unlimited inbound messages + 10 campaigns / month',
        '- Platform Business: 60,000 messages + unlimited inbound messages + 20 campaigns / month',
        '- Platform Enterprise: unlimited messages + 30 campaigns',
        '',
        'Each plan is limited to one WhatsApp number. You can purchase multiple plans if you have multiple numbers.',
        '',
        '*Find more information about the different plan prices and features here:*',
        'https://sagi-digital.com/#pricing'
      ].join('\n')
      return reply
    }
  },

  // Sample function to load user information from a CRM
  {
    name: 'loadUserInformation',
    description: 'Find user name and email from the CRM',
    parameters: {
      type: 'object',
      properties: {}
    },
    run: async ({ parameters, response, data, device, messages }) => {
      // You may call an remote API and run a database query
      const reply = 'I am sorry, I am not able to access the CRM at the moment. Please try again later.'
      return reply
    }
  },

  // Sample function to verify the current date and time
  {
    name: 'verifyMeetingAvaiability',
    description: 'Verify if a given date and time is available for a meeting before booking it',
    parameters: {
      type: 'object',
      properties: {
        date: { type: 'string', format: 'date-time', description: 'Date of the meeting' }
      },
      required: ['date']
    },
    run: async ({ parameters, response, data, device, messages }) => {
      console.log('=> verifyMeetingAvaiability call parameters:', parameters)
      // Example: you can make an API call to verify the date and time availability and return the confirmation or rejection message
      const date = new Date(parameters.date)
      if (date.getUTCDay() > 5) {
        return 'Not available on weekends'
      }
      if (date.getHours() < 9 || date.getHours() > 17) {
        return 'Not available outside business hours: 9 am to 5 pm'
      }
      return 'Available'
    }
  },

  // Sample function to determine the current date and time
  {
    name: 'bookSalesMeeting',
    description: 'Book a sales or demo meeting with the customer on a specific date and time',
    parameters: {
      type: 'object',
      properties: {
        date: { type: 'string', format: 'date-time', description: 'Date of the meeting' }
      },
      required: ['date']
    },
    run: async ({ parameters, response, data, device, messages }) => {
      console.log('=> bookSalesMeeting call parameters:', parameters)
      // Make an API call to book the meeting and return the confirmation or rejection message
      return 'Meeting booked successfully. You will receive a confirmation email shortly.'
    }
  },

  // Sample function to determine the current date and time
  {
    name: 'currentDateAndTime',
    description: 'What is the current date and time',
    run: async ({ parameters, response, data, device, messages }) => {
      return new Date().toLocaleString()
    }
  }
]

export default functions

import path from 'path'
import fs from 'fs/promises'
import OpenAI from 'openai'
import config from './config.js'
import { state, stats } from './store.js'
import * as actions from './actions.js'

// Initialize OpenAI client
const ai = new OpenAI({ apiKey: config.openaiKey })

// Determine if a given inbound message can be replied by the AI bot
function canReply ({ data, device }) {
  const { chat } = data

  // Skip chat if already assigned to a team member
  if (chat.owner?.agent) {
    return false
  }

  // Skip messages receive from the same number: prevent self-reply loops
  if (chat.fromNumber === device.phone) {
    console.log('[debug] Skip message: cannot chat with your own WhatsApp number:', device.phone)
    return false
  }

  // Skip messages from group chats and channels
  if (chat.type !== 'chat') {
    return false
  }

  // Skip replying chat if it has one of the configured labels, when applicable
  if (config.skipChatWithLabels && config.skipChatWithLabels.length && chat.labels && chat.labels.length) {
    if (config.skipChatWithLabels.some(label => chat.labels.includes(label))) {
      return false
    }
  }

  // Only reply to chats that were whitelisted, when applicable
  if (config.numbersWhitelist && config.numbersWhitelist.length && chat.fromNumber) {
    if (config.numbersWhitelist.some(number => number === chat.fromNumber || chat.fromNumber.slice(1) === number)) {
      return true
    } else {
      return false
    }
  }

  // Skip replying to chats that were explicitly blacklisted, when applicable
  if (config.numbersBlacklist && config.numbersBlacklist.length && chat.fromNumber) {
    if (config.numbersBlacklist.some(number => number === chat.fromNumber || chat.fromNumber.slice(1) === number)) {
      return false
    }
  }

  // Skip replying to blocked chats
  if (chat.status === 'banned' || chat.waStatus === 'banned') {
    return false
  }

  // Skip blocked contacts
  if (chat.contact?.status === 'blocked') {
    return false
  }

  // Skip replying chats that were archived, when applicable
  if (config.skipArchivedChats && (chat.status === 'archived' || chat.waStatus === 'archived')) {
    return false
  }

  return true
}

// Send message back to the user and perform post-message required actions like
// adding labels to the chat or updating the chat's contact metadata
function replyMessage ({ data, device, useAudio }) {
  return async ({ message, ...params }, { text } = {}) => {
    const { phone } = data.chat.contact

    // If audio mode, create a new voice message
    let fileId = null
    if (config.features.audioOutput && !text && message.length <= 4096 && (useAudio || config.features.audioOnly)) {
      // Send recording audio chat state in background
      actions.sendTypingState({ data, device, action: 'recording' })

      // Generate audio recording
      console.log('[info] generating audio response for chat:', data.fromNumber, message)
      const audio = await ai.audio.speech.create({
        input: message,
        model: 'tts-1',
        voice: config.features.voice,
        response_format: 'mp3',
        speed: config.features.voiceSpeed
      })

      const timestamp = Date.now().toString(16)
      const random = Math.floor(Math.random() * 0xfffff).toString(16)
      fileId = `${timestamp}${random}`

      const filepath = path.join(`${config.tempPath}`, `${fileId}.mp3`)
      const buffer = Buffer.from(await audio.arrayBuffer())
      await fs.writeFile(filepath, buffer)
    } else {
      // Send text typing chat state in background
      actions.sendTypingState({ data, device, action: 'typing' })
    }

    const payload = {
      phone,
      device: device.id,
      message,
      reference: 'bot:chatgpt',
      ...params
    }

    if (fileId) {
      payload.message = undefined
      // Get base URL and add path to the webhook
      const schema = new URL(config.webhookUrl)
      const url = `${schema.protocol}//${schema.host}${path.dirname(schema.pathname)}files/${fileId}${schema.search}`
      payload.media = { url, format: 'ptt' }
    }

    const msg = await actions.sendMessage(payload)

    // Store sent message in chat history
    state[data.chat.id] = state[data.chat.id] || {}
    state[data.chat.id][msg.waId] = {
      id: msg.waId,
      flow: 'outbound',
      date: msg.createdAt,
      body: message
    }

    // Increase chat messages quota
    stats[data.chat.id] = stats[data.chat.id] || { messages: 0, time: Date.now() }
    stats[data.chat.id].messages += 1

    // Add bot-managed chat labels, if required
    if (config.setLabelsOnBotChats.length) {
      const labels = config.setLabelsOnBotChats.filter(label => (data.chat.labels || []).includes(label))
      if (labels.length) {
        await actions.updateChatLabels({ data, device, labels })
      }
    }

    // Add bot-managed chat metadata, if required
    if (config.setMetadataOnBotChats.length) {
      const metadata = config.setMetadataOnBotChats.filter(entry => entry && entry.key && entry.value).map(({ key, value }) => ({ key, value }))
      await actions.updateChatMetadata({ data, device, metadata })
    }
  }
}

function parseArguments (json) {
  try {
    return JSON.parse(json || '{}')
  } catch (err) {
    return {}
  }
}

function hasChatMetadataQuotaExceeded (chat) {
  const key = chat.contact?.metadata?.find(x => x.key === 'bot:chatgpt:status')
  if (key?.value === 'too_many_messages') {
    return true
  }
  return false
}

// Messages quota per chat
function hasChatMessagesQuota (chat) {
  const stat = stats[chat.id] = stats[chat.id] || { messages: 0, time: Date.now() }
  if (stat.messages >= config.limits.maxMessagesPerChat) {
    // Reset chat messages quota after the time limit
    if ((Date.now() - stat.time) >= (config.limits.maxMessagesPerChatTime * 1000)) {
      stat.messages = 0
      stat.time = Date.now()
      return true
    }
    return false
  }
  return true
}

// Update chat metadata if messages quota is exceeded
async function updateChatOnMessagesQuota ({ data, device }) {
  const { chat } = data
  if (hasChatMetadataQuotaExceeded(chat)) {
    return false
  }

  await Promise.all([
    // Assign chat to an agent
    actions.assignChatToAgent({
      data,
      device,
      force: true
    }),
    // Update metadata status to 'too_many_messages'
    actions.updateChatMetadata({
      data,
      device,
      metadata: [{ key: 'bot:chatgpt:status', value: 'too_many_messages' }]
    })
  ])
}

// Process message received from the user on every new inbound webhook event
export async function processMessage ({ data, device } = {}, { rag } = {}) {
  // Can reply to this message?
  if (!canReply({ data, device })) {
    return console.log('[info] Skip message - chat is not eligible to reply due to active filters:', data.fromNumber, data.date, data.body)
  }

  const { chat } = data

  // Chat has enough messages quota
  if (!hasChatMessagesQuota(chat)) {
    console.log('[info] Skip message - chat has reached the maximum messages quota:', data.fromNumber)
    return await updateChatOnMessagesQuota({ data, device })
  }

  // Update chat status metadata if messages quota is not exceeded
  if (hasChatMetadataQuotaExceeded(chat)) {
    actions.updateChatMetadata({ data, device, metadata: [{ key: 'bot:chatgpt:status', value: 'active' }] })
      .catch(err => console.error('[error] failed to update chat metadata:', data.chat.id, err.message))
  }

  // If audio message, transcribe it to text
  if (data.type === 'audio') {
    const noAudioMessage = config.templateMessages.noAudioAccepted || 'Audio messages are not supported: gently ask the user to send text messages only.'
    if (config.features.audioInput && +data.media.meta?.duration <= config.limits.maxAudioDuration) {
      const transcription = await actions.transcribeAudio({ message: data, device })
      if (transcription) {
        data.body = transcription
      } else {
        console.error('[error] failed to transcribe audio message:', data.fromNumber, data.date, data.media.id)
        data.body = noAudioMessage
      }
    } else {
      // console.log('[info] skip message - audio input processing is disabled, enable it on config.js:', data.fromNumber)
      data.body = noAudioMessage
    }
  }

  // Extract input body per message type
  if (data.type === 'video' && !data.body) {
    data.body = 'Video message cannot be processed. Send a text message.'
  }
  if (data.type === 'document' && !data.body) {
    data.body = 'Document message cannot be processed. Send a text message.'
  }
  if (data.type === 'location' && !data.body) {
    data.body = `Location: ${data.location.name || ''} ${data.location.address || ''}`
  }
  if (data.type === 'poll' && !data.body) {
    data.body = `Poll: ${data.poll.name || 'unamed'}\n${data.poll.options.map(x => '-' + x.name).join('\n')}`
  }
  if (data.type === 'event' && !data.body) {
    data.body = [
      `Meeting event: ${data.event.name || 'unamed'}`,
      `Description: ${data.event.description || 'no description'}`,
      `Date: ${data.event.date || 'no date'}`,
      `Location: ${data.event.location || 'undefined location'}``Call link: ${data.event.link || 'no call link'}`
    ].join('\n')
  }
  if (data.type === 'contacts') {
    data.body = data.contacts.map(x => `- Contact card: ${x.formattedName || x.name || x.firstName || ''} - Phone: ${x.phones ? x.phones.map(x => x.number || x.waid) : ''}}`).join('\n')
  }

  // User message input
  const body = data?.body?.trim().slice(0, Math.min(config.limits.maxInputCharacters, 10000))
  console.log('[info] New inbound message received:', chat.id, data.type, body || '<empty message>')

  // If input message is audio, reply with an audio message, unless features.audioOutput is false
  const useAudio = data.type === 'audio'

  // Create partial function to reply the chat
  const reply = replyMessage({ data, device, useAudio })

  if (!body) {
    if (data.type !== 'image' || (data.type === 'image' && !config.features.imageInput) || (data.type === 'image' && config.features.imageInput && data.media.size > config.limits.maxImageSize)) {
      // Default to unknown command response
      const unknownCommand = `${config.unknownCommandMessage}\n\n${config.defaultMessage}`
      await reply({ message: unknownCommand }, { text: true })
    }
  }

  // Assign the chat to an random agent
  if (/^human|person|help|stop$/i.test(body) || /^human/i.test(body)) {
    actions.assignChatToAgent({ data, device, force: true }).catch(err => {
      console.error('[error] failed to assign chat to user:', data.chat.id, err.message)
    })
    const message = config.templateMessages.chatAssigned || 'You will be contact shortly by someone from our team. Thank you for your patience.'
    return await reply({ message }, { text: true })
  }

  // Generate response using AI
  if (!state[data.chat.id]) {
    console.log('[info] fetch previous messages history for chat:', data.chat.id)
    await actions.pullChatMessages({ data, device })
  }

  // Chat messages history
  const chatMessages = state[data.chat.id] = state[data.chat.id] || {}

  // Chat configuration
  const { apiBaseUrl } = config

  // Compose chat previous messages to context awareness better AI responses
  const previousMessages = Object.values(chatMessages)
    .sort((a, b) => +new Date(b.date) - +new Date(a.date))
    .slice(0, 40)
    .reverse()
    .map(message => {
      if (message.flow === 'inbound' && !message.body && message.type === 'image' && config.features.imageInput && message.media.size <= config.limits.maxImageSize) {
        const url = apiBaseUrl + message.media.links.download.slice(3) + '?token=' + config.apiKey
        return {
          role: 'user',
          content: [{
            type: 'image_url',
            image_url: { url }
          }, message.media.caption ? { type: 'text', text: message.media.caption } : null].filter(x => x)
        }
      } else {
        return {
          role: message.flow === 'inbound' ? 'user' : (message.role || 'assistant'),
          content: message.body
        }
      }
    })
    .filter(message => message.content).slice(-(+config.limits.chatHistoryLimit || 20))

  const messages = [
    { role: 'system', content: config.botInstructions },
    ...previousMessages
  ]

  const lastMessage = messages[messages.length - 1]
  if (lastMessage.role !== 'user' || lastMessage.content !== body) {
    if (config.features.imageInput && data.type === 'image' && !data.body && data.media.size <= config.limits.maxImageSize) {
      const url = apiBaseUrl + data.media.links.download.slice(3) + '?token=' + config.apiKey
      messages.push({
        role: 'user',
        content: [
          {
            type: 'image_url',
            image_url: { url }
          },
          data.media.caption ? { type: 'text', text: data.media.caption } : null
        ].filter(x => x)
      })
    } else {
      messages.push({ role: 'user', content: body })
    }
  }

  // Add tool functions to the AI model, if available
  const tools = (config.functions || []).filter(x => x && x.name).map(({ name, description, parameters, strict }) => (
    { type: 'function', function: { name, description, parameters, strict } }
  ))

  // If knowledge is enabled, query it
  if (rag && body && (data.type === 'text' || data.type === 'audio')) {
    const result = await rag.query(body)
    // const result = await rag.search(body)
    console.log('==> rag result:', result?.content)
    if (result?.content) {
      messages.push({ role: 'assistant', content: result.content })
    }
  }

  // Generate response using AI
  let completion = await ai.chat.completions.create({
    tools,
    messages,
    model: config.openaiModel,
    max_completion_tokens: config.limits.maxOutputTokens,
    temperature: config.inferenceParams.temperature,
    user: `${device.id}_${chat.id}`
  })

  // Reply with unknown / default response on invalid/error
  if (!completion.choices?.length) {
    const unknownCommand = `${config.unknownCommandMessage}\n\n${config.defaultMessage}`
    return await reply({ message: unknownCommand })
  }

  // Process tool function calls, if required by the AI model
  const maxCalls = 10
  let [response] = completion.choices
  let count = 0
  while (response?.message?.tool_calls?.length && count < maxCalls) {
    count += 1

    // If response is a function call, return the custom result
    const responses = []

    // Store tool calls in history
    messages.push({ role: 'assistant', tool_calls: response.message.tool_calls })

    // Call tool functions triggerd by the AI
    const calls = response.message.tool_calls.filter(x => x.id && x.type === 'function')
    for (const call of calls) {
      const func = config.functions.find(x => x.name === call.function.name)
      if (func && typeof func.run === 'function') {
        const parameters = parseArguments(call.function.arguments)
        console.log('[info] run function:', call.function.name, parameters)

        // Run the function and get the response message
        const message = await func.run({ parameters, response, data, device, messages })
        if (message) {
          responses.push({ role: 'tool', content: message, tool_call_id: call.id })
        }
      } else if (!func) {
        console.error('[warning] missing function call in config.functions', call.function.name)
      }
    }

    if (!responses.length) {
      break
    }

    // Add tool responses to the chat history
    messages.push(...responses)

    // Generate a new response based on the tool functions responses
    completion = await ai.chat.completions.create({
      tools,
      messages,
      temperature: 0.2,
      model: config.openaiModel,
      user: `${device.id}_${chat.id}`
    })

    // Reply with unknown / default response on invalid/error
    if (!completion.choices?.length) {
      break
    }
    // Reply with unknown / default response on invalid/error
    response = completion.choices[0]
    if (!response || response.finish_reason === 'stop') {
      break
    }
  }

  // Reply with the AI generated response
  if (completion.choices?.length) {
    return await reply({ message: response?.message?.content || config.unknownCommandMessage })
  }

  // Unknown default response
  const unknownCommand = `${config.unknownCommandMessage}\n\n${config.defaultMessage}`
  await reply({ message: unknownCommand })
}

import fs from 'fs'
import axios from 'axios'
import OpenAI from 'openai'
import config from './config.js'
import { state, cache, cacheTTL } from './store.js'

// Initialize OpenAI client
const ai = new OpenAI({ apiKey: config.openaiKey })

// Base URL API endpoint. Do not edit!
const API_URL = config.apiBaseUrl

// Function to send a message using the SnakeChat API
export async function sendMessage ({ phone, message, media, device, ...fields }) {
  const url = `${API_URL}/messages`
  const body = {
    phone,
    message,
    media,
    device,
    ...fields,
    enqueue: 'never'
  }

  let retries = 3
  while (retries) {
    retries -= 1
    try {
      const res = await axios.post(url, body, {
        headers: { Authorization: config.apiKey }
      })
      console.log('[info] Message sent:', phone, res.data.id, res.data.status)
      return res.data
    } catch (err) {
      console.error('[error] failed to send message:', phone, message || (body.list ? body.list.description : '<no message>'), err.response ? err.response.data : err)
    }
  }
  return false
}

export async function pullMembers (device) {
  if (cache.members && +cache.members.time && (Date.now() - +cache.members.time) < cacheTTL) {
    return cache.members.data
  }
  const url = `${API_URL}/devices/${device.id}/team`
  const { data: members } = await axios.get(url, { headers: { Authorization: config.apiKey } })
  cache.members = { data: members, time: Date.now() }
  return members
}

export async function validateMembers (device, members) {
  const validateMembers = (config.teamWhitelist || []).concat(config.teamBlacklist || [])
  for (const id of validateMembers) {
    if (typeof id !== 'string' || id.length !== 24) {
      return exit('Team user ID in config.teamWhitelist and config.teamBlacklist must be a 24 characters hexadecimal value:', id)
    }
    const exists = members.some(user => user.id === id)
    if (!exists) {
      return exit('Team user ID in config.teamWhitelist or config.teamBlacklist does not exist:', id)
    }
  }
}

export async function createLabels (device) {
  const labels = cache.labels.data || []
  const requiredLabels = (config.setLabelsOnUserAssignment || []).concat(config.setLabelsOnBotChats || [])
  const missingLabels = requiredLabels.filter(label => labels.every(l => l.name !== label))
  for (const label of missingLabels) {
    console.log('[info] creating missing label:', label)
    const url = `${API_URL}/devices/${device.id}/labels`
    const body = {
      name: label.slice(0, 30).trim(),
      color: [
        'tomato', 'orange', 'sunflower', 'bubble',
        'rose', 'poppy', 'rouge', 'raspberry',
        'purple', 'lavender', 'violet', 'pool',
        'emerald', 'kelly', 'apple', 'turquoise',
        'aqua', 'gold', 'latte', 'cocoa'
      ][Math.floor(Math.random() * 20)],
      description: 'Automatically created label for the chatbot'
    }
    try {
      await axios.post(url, body, { headers: { Authorization: config.apiKey } })
    } catch (err) {
      console.error('[error] failed to create label:', label, err.message)
    }
  }
  if (missingLabels.length) {
    await pullLabels(device, { force: true })
  }
}

export async function pullLabels (device, { force } = {}) {
  if (!force && cache.labels && +cache.labels.time && (Date.now() - +cache.labels.time) < cacheTTL) {
    return cache.labels.data
  }
  const url = `${API_URL}/devices/${device.id}/labels`
  const { data: labels } = await axios.get(url, { headers: { Authorization: config.apiKey } })
  cache.labels = { data: labels, time: Date.now() }
  return labels
}

export async function updateChatLabels ({ data, device, labels }) {
  const url = `${API_URL}/chat/${device.id}/chats/${data.chat.id}/labels`
  const newLabels = (data.chat.labels || [])
  for (const label of labels) {
    if (newLabels.includes(label)) {
      newLabels.push(label)
    }
  }
  if (newLabels.length) {
    console.log('[info] update chat labels:', data.chat.id, newLabels)
    await axios.patch(url, newLabels, { headers: { Authorization: config.apiKey } })
  }
}

export async function updateChatMetadata ({ data, device, metadata }) {
  const url = `${API_URL}/chat/${device.id}/contacts/${data.chat.id}/metadata`
  const entries = []
  const contactMetadata = data.chat.contact.metadata
  for (const entry of metadata) {
    if (entry && entry.key && entry.value) {
      const value = typeof entry.value === 'function' ? entry.value() : entry.value
      if (!entry.key || !value || typeof entry.key !== 'string' || typeof value !== 'string') {
        continue
      }
      if (contactMetadata && contactMetadata.some(e => e.key === entry.key && e.value === value)) {
        continue // skip if metadata entry is already present
      }
      entries.push({
        key: entry.key.slice(0, 30).trim(),
        value: value.slice(0, 1000).trim()
      })
    }
  }
  if (entries.length) {
    await axios.patch(url, entries, { headers: { Authorization: config.apiKey } })
  }
}

export async function selectAssignMember (device) {
  const members = await pullMembers(device)

  const isMemberEligible = (member) => {
    if (config.teamBlacklist.length && config.teamBlacklist.includes(member.id)) {
      return false
    }
    if (config.teamWhitelist.length && !config.teamWhitelist.includes(member.id)) {
      return false
    }
    if (config.assignOnlyToOnlineMembers && (member.availability.mode !== 'auto' || ((Date.now() - +new Date(member.lastSeenAt)) > 30 * 60 * 1000))) {
      return false
    }
    if (config.skipTeamRolesFromAssignment && config.skipTeamRolesFromAssignment.some(role => member.role === role)) {
      return false
    }
    return true
  }

  const activeMembers = members.filter(member => member.status === 'active' && isMemberEligible(member))
  if (!activeMembers.length) {
    return console.log('[warning] Unable to assign chat: no eligible team members')
  }

  const targetMember = activeMembers[activeMembers.length * Math.random() | 0]
  return targetMember
}

async function assignChat ({ member, data, device }) {
  const url = `${API_URL}/chat/${device.id}/chats/${data.chat.id}/owner`
  const body = { agent: member.id }
  await axios.patch(url, body, { headers: { Authorization: config.apiKey } })

  if (config.setMetadataOnAssignment && config.setMetadataOnAssignment.length) {
    const metadata = config.setMetadataOnAssignment.filter(entry => entry && entry.key && entry.value).map(({ key, value }) => ({ key, value }))
    await updateChatMetadata({ data, device, metadata })
  }
}

export async function assignChatToAgent ({ data, device, force }) {
  if (!config.enableMemberChatAssignment && !force) {
    return console.log('[debug] Unable to assign chat: member chat assignment is disabled. Enable it in config.enableMemberChatAssignment = true')
  }
  try {
    const member = await selectAssignMember(device)
    if (member) {
      let updateLabels = []

      // Remove labels before chat assigned, if required
      if (config.removeLabelsAfterAssignment && config.setLabelsOnBotChats && config.setLabelsOnBotChats.length) {
        const labels = (data.chat.labels || []).filter(label => !config.setLabelsOnBotChats.includes(label))
        console.log('[info] remove labels before assiging chat to user', data.chat.id, labels)
        if (labels.length) {
          updateLabels = labels
        }
      }

      // Set labels on chat assignment, if required
      if (config.setLabelsOnUserAssignment && config.setLabelsOnUserAssignment.length) {
        let labels = (data.chat.labels || [])
        if (updateLabels.length) {
          labels = labels.filter(label => !updateLabels.includes(label))
        }
        for (const label of config.setLabelsOnUserAssignment) {
          if (!labels.includes(label)) {
            updateLabels.push(label)
          }
        }
      }

      if (updateLabels.length) {
        console.log('[info] set labels on chat assignment to user', data.chat.id, updateLabels)
        await updateChatLabels({ data, device, labels: updateLabels })
      }

      console.log('[info] automatically assign chat to user:', data.chat.id, member.displayName, member.email)
      await assignChat({ member, data, device })
    } else {
      console.log('[info] Unable to assign chat: no eligible or available team members based on the current configuration:', data.chat.id)
    }
    return member
  } catch (err) {
    console.error('[error] failed to assign chat:', data.id, data.chat.id, err)
  }
}

export async function pullChatMessages ({ data, device }) {
  try {
    const url = `${API_URL}/chat/${device.id}/messages/?chat=${data.chat.id}&limit=25`
    const res = await axios.get(url, { headers: { Authorization: config.apiKey } })
    state[data.chat.id] = res.data.reduce((acc, message) => {
      acc[message.id] = message
      return acc
    }, state[data.chat.id] || {})
    return res.data
  } catch (err) {
    console.error('[error] failed to pull chat messages history:', data.id, data.chat.id, err)
  }
}

// Find an active WhatsApp device connected to the SnakeChat API
export async function loadDevice () {
  const url = `${API_URL}/devices`
  const { data } = await axios.get(url, {
    headers: { Authorization: config.apiKey }
  })
  if (config.device && !config.device.includes(' ')) {
    if (/^[a-f0-9]{24}$/i.test(config.device) === false) {
      return exit('Invalid WhatsApp device ID: must be 24 characers hexadecimal value. Get the device ID here: https://chat.sagi-digital.com/number')
    }
    return data.find(device => device.id === config.device)
  }
  return data.find(device => device.status === 'operative')
}

// Function to register a Ngrok tunnel webhook for the chatbot
// Only used in local development mode
export async function registerWebhook (tunnel, device) {
  const webhookUrl = `${tunnel}/webhook`

  const url = `${API_URL}/webhooks`
  const { data: webhooks } = await axios.get(url, {
    headers: { Authorization: config.apiKey }
  })

  const findWebhook = webhook => {
    return (
      webhook.url === webhookUrl &&
      webhook.device === device.id &&
      webhook.status === 'active' &&
      webhook.events.includes('message:in:new')
    )
  }

  // If webhook already exists, return it
  const existing = webhooks.find(findWebhook)
  if (existing) {
    return existing
  }

  for (const webhook of webhooks) {
    // Delete previous ngrok webhooks
    if (webhook.url.includes('ngrok-free.app') || webhook.url.startsWith(tunnel)) {
      const url = `${API_URL}/webhooks/${webhook.id}`
      await axios.delete(url, { headers: { Authorization: config.apiKey } })
    }
  }

  await new Promise(resolve => setTimeout(resolve, 500))
  const data = {
    url: webhookUrl,
    name: 'Chatbot',
    events: ['message:in:new'],
    device: device.id
  }

  const { data: webhook } = await axios.post(url, data, {
    headers: { Authorization: config.apiKey }
  })

  return webhook
}

export async function transcribeAudio ({ message, device }) {
  if (!message?.media?.id) {
    return false
  }

  try {
    const url = `${API_URL}/chat/${device.id}/files/${message.media.id}/download`
    const response = await axios.get(url, {
      headers: { Authorization: config.apiKey },
      responseType: 'stream'
    })
    if (response.status !== 200) {
      return false
    }

    const tmpFile = `${message.media.id}.mp3`
    await new Promise((resolve, reject) => {
      const writer = fs.createWriteStream(tmpFile)
      response.data.pipe(writer)
      writer.on('finish', () => resolve())
      writer.on('error', reject)
    })

    const transcription = await ai.audio.transcriptions.create({
      file: fs.createReadStream(tmpFile),
      model: 'whisper-1',
      response_format: 'text'
    })
    await fs.promises.unlink(tmpFile)
    return transcription
  } catch (err) {
    console.error('[error] failed to transcribe audio:', message.fromNumber, message.media.id, err.message)
    return false
  }
}

export async function sendTypingState ({ data, device, action }) {
  const url = `${API_URL}/chat/${device.id}/typing`
  const body = { action: action || 'typing', duration: 10, chat: data.fromNumber }
  try {
    await axios.post(url, body, { headers: { Authorization: config.apiKey } })
  } catch (err) {
    console.error('[error] failed to send typing state:', data.fromNumber, body, err.message)
  }
}

export function exit (msg, ...args) {
  console.error('[error]', msg, ...args)
  process.exit(1)
}

import fs from 'fs'
import ngrok from 'ngrok'
import nodemon from 'nodemon'
import config from './config.js'
import server from './server.js'
import * as actions from './actions.js'
const { exit } = actions

// Function to create a Ngrok tunnel and register the webhook dynamically
async function createTunnel () {
  let retries = 3

  try {
    await ngrok.upgradeConfig({ relocate: false })
  } catch (err) {
    console.error('[warning] Failed to upgrade Ngrok config:', err.message)
  }

  while (retries) {
    retries -= 1
    try {
      const tunnel = await ngrok.connect({
        addr: config.port,
        authtoken: config.ngrokToken,
        path: () => config.ngrokPath
      })
      console.log(`Ngrok tunnel created: ${tunnel}`)
      config.webhookUrl = tunnel
      return tunnel
    } catch (err) {
      console.error('[error] Failed to create Ngrok tunnel:', err.message)
      await ngrok.kill()
      await new Promise(resolve => setTimeout(resolve, 1000))
    }
  }

  throw new Error('Failed to create Ngrok tunnel')
}

// Development server using nodemon to restart the bot on file changes
async function devServer () {
  const tunnel = await createTunnel()

  nodemon({
    script: 'bot.js',
    ext: 'js',
    watch: ['*.js', 'src/**/*.js'],
    exec: `WEBHOOK_URL=${tunnel} DEV=false npm run start`
  }).on('restart', () => {
    console.log('[info] Restarting bot after changes...')
  }).on('quit', () => {
    console.log('[info] Closing bot...')
    ngrok.kill().then(() => process.exit(0))
  })
}

const loadWhatsAppDevice = async () => {
  try {
    const device = await actions.loadDevice()
    if (!device || device.status !== 'operative') {
      return exit('No active WhatsApp numbers in your account. Please connect a WhatsApp number in your SnakeChat account:\nhttps://chat.sagi-digital.com/create')
    }
    return device
  } catch (err) {
    if (err.response?.status === 403) {
      return exit('Unauthorized SnakeChat API key: please make sure you are correctly setting the API token, obtain your API key here:\nhttps://chat.sagi-digital.com/developers/apikeys')
    }
    if (err.response?.status === 404) {
      return exit('No active WhatsApp numbers in your account. Please connect a WhatsApp number in your SnakeChat account:\nhttps://chat.sagi-digital.com/create')
    }
    return exit('Failed to load WhatsApp number:', err.message)
  }
}

// Initialize chatbot server
async function main () {
  // API key must be provided
  if (!config.apiKey || config.apiKey.length < 60) {
    return exit('Please sign up in SnakeChat and obtain your API key:\nhttps://chat.sagi-digital.com/apikeys')
  }

  // OpenAI API key must be provided
  if (!config.openaiKey || config.openaiKey.length < 45) {
    return exit('Missing required OpenAI API key: please sign up for free and obtain your API key:\nhttps://platform.openai.com/account/api-keys')
  }

  // Create dev mode server with Ngrok tunnel and nodemon
  if (process.env.DEV === 'true' && !config.production) {
    return devServer()
  }

  // Find a WhatsApp number connected to the SnakeChat API
  const device = await loadWhatsAppDevice()
  if (!device) {
    return exit('No active WhatsApp numbers in your account. Please connect a WhatsApp number in your SnakeChat account:\nhttps://chat.sagi-digital.com/create')
  }
  if (device.session.status !== 'online') {
    return exit(`WhatsApp number (${device.alias}) is not online. Please make sure the WhatsApp number in your SnakeChat account is properly connected:\nhttps://chat.sagi-digital.com/${device.id}/scan`)
  }
  if (device.billing.subscription.product !== 'io') {
    return exit(`WhatsApp number plan (${device.alias}) does not support inbound messages. Please upgrade the plan here:\nhttps://chat.sagi-digital.com/${device.id}/plan?product=io`)
  }

  // Create tmp folder
  if (!fs.existsSync(config.tempPath)) {
    fs.mkdirSync(config.tempPath)
  }

  // Pre-load device labels and team mebers
  const [members] = await Promise.all([
    actions.pullMembers(device),
    actions.pullLabels(device)
  ])

  // Create labels if they don't exist
  await actions.createLabels(device)

  // Validate whitelisted and blacklisted members exist
  await actions.validateMembers(members)

  server.device = device
  console.log('[info] Using WhatsApp connected number:', device.phone, device.alias, `(ID = ${device.id})`)

  // Start server
  await server.listen(config.port, () => {
    console.log(`Server listening on port ${config.port}`)
  })

  if (config.production) {
    console.log('[info] Validating webhook endpoint...')
    if (!config.webhookUrl) {
      return exit('Missing required environment variable: WEBHOOK_URL must be present in production mode')
    }
    const webhook = await actions.registerWebhook(config.webhookUrl, device)
    if (!webhook) {
      return exit(`Missing webhook active endpoint in production mode: please create a webhook endpoint that points to the chatbot server:\nhttps://chat.sagi-digital.com/${device.id}/webhooks`)
    }
    console.log('[info] Using webhook endpoint in production mode:', webhook.url)
  } else {
    console.log('[info] Registering webhook tunnel...')
    const tunnel = config.webhookUrl || await createTunnel()
    const webhook = await actions.registerWebhook(tunnel, device)
    if (!webhook) {
      console.error('Failed to connect webhook. Please try again.')
      await ngrok.kill()
      return process.exit(1)
    }
  }

  console.log('[info] Chatbot server ready and waiting for messages!')
}

main().catch(err => {
  exit('Failed to start chatbot server:', err)
})

import path from 'path'
import fs from 'fs/promises'
import { createReadStream } from 'fs'
import express from 'express'
import bodyParser from 'body-parser'
import config from './config.js'
import * as bot from './bot.js'
import * as actions from './actions.js'

// Create web server
const app = express()

// Middleware to parse incoming request bodies
app.use(bodyParser.json())

// Index route
app.get('/', (req, res) => {
  res.send({
    name: 'chatbot',
    description: 'WhatsApp ChatGPT powered chatbot for SnakeChat',
    endpoints: {
      webhook: {
        path: '/webhook',
        method: 'POST'
      },
      sendMessage: {
        path: '/message',
        method: 'POST'
      },
      sample: {
        path: '/sample',
        method: 'GET'
      }
    }
  })
})

// POST route to handle incoming webhook messages
app.post('/webhook', (req, res) => {
  const { body } = req
  if (!body || !body.event || !body.data) {
    return res.status(400).send({ message: 'Invalid payload body' })
  }
  if (body.event !== 'message:in:new') {
    return res.status(202).send({ message: 'Ignore webhook event: only message:in:new is accepted' })
  }

  // Send immediate response to acknowledge the webhook event
  res.send({ ok: true })

  // Process message response in background
  bot.processMessage(body, { rag: app.rag }).catch(err => {
    console.error('[error] failed to process inbound message:', body.id, body.data.fromNumber, body.data.body, err)
  })
})

// Send message on demand
app.post('/message', (req, res) => {
  const { body } = req
  if (!body || !body.phone || !body.message) {
    return res.status(400).send({ message: 'Invalid payload body' })
  }

  actions.sendMessage(body).then((data) => {
    res.send(data)
  }).catch(err => {
    res.status(+err.status || 500).send(err.response
      ? err.response.data
      : {
          message: 'Failed to send message'
        })
  })
})

// Send a sample message to your own number, or to a number specified in the query string
app.get('/sample', (req, res) => {
  const { phone, message } = req.query
  const data = {
    phone: phone || app.device.phone,
    message: message || 'Hello World from SnakeChat!',
    device: app.device.id
  }
  actions.sendMessage(data).then((data) => {
    res.send(data)
  }).catch(err => {
    res.status(+err.status || 500).send(err.response
      ? err.response.data
      : {
          message: 'Failed to send sample message'
        })
  })
})

async function fileExists (filepath) {
  try {
    await fs.access(filepath, fs.constants.F_OK)
    return true
  } catch (err) {
    return false
  }
}

async function fileSize (filepath) {
  try {
    const stat = await fs.stat(filepath)
    return stat.size
  } catch (err) {
    return -1
  }
}

app.get('/files/:id', async (req, res) => {
  if (!(/^[a-f0-9]{15,18}$/i.test(req.params.id))) {
    return res.status(400).send({ message: 'Invalid ID' })
  }

  const filename = `${req.params.id}.mp3`
  const filepath = path.join(config.tempPath, filename)
  if (!(await fileExists(filepath))) {
    return res.status(404).send({ message: 'Invalid or deleted file' })
  }

  const size = await fileSize(filepath)
  if (!size) {
    return res.status(404).send({ message: 'Invalid or deleted file' })
  }

  res.set('Content-Length', size)
  res.set('Content-Type', 'application/octet-stream')

  createReadStream(filepath).pipe(res)

  res.once('close', () => {
    fs.unlink(filepath).catch(err => {
      console.error('[error] failed to delete temp file:', filepath, err.message)
    })
  })
})

app.use((err, req, res, next) => {
  res.status(+err.status || 500).send({
    message: `Unexpected error: ${err.message}`
  })
})

export default app

// Cache time-to-live in milliseconds
export const cacheTTL = 10 * 60 * 1000

// In-memory cache store
export const cache = {}

// In-memory store for a simple state machine per chat
// You can use a database instead for persistence
export const state = {}

// In-memory store for message counter per chat
export const stats = {}

{
  "name": "whatsapp-chatgpt-bot-demo",
  "version": "1.0.0",
  "private": true,
  "license": "MIT",
  "engine": {
    "node": ">=16"
  },
  "type": "module",
  "scripts": {
    "start": "node main.js",
    "dev": "DEV=true npm run start",
    "lint": "./node_modules/.bin/standard ."
  },
  "dependencies": {
    "axios": "^1.3.6",
    "express": "^4.18.2",
    "ngrok": "^5.0.0-beta.2",
    "nodemon": "^2.0.22",
    "openai": "^4.14.2"
  },
  "devDependencies": {
    "standard": "^17.1.0"
  }
}