import { toChatMessage } from '@models/ChatMessage'
import { executeSerial } from '@services/pluginService'
import { useAtomValue, useSetAtom } from 'jotai'
import { useEffect, useState } from 'react'
import { DataService } from '@janhq/core'
import { addOldMessagesAtom } from '@helpers/atoms/ChatMessage.atom'
import {
  currentConversationAtom,
  conversationStatesAtom,
  updateConversationHasMoreAtom,
} from '@helpers/atoms/Conversation.atom'

/**
 * Custom hooks to get chat messages for current(active) conversation
 *
 * @param offset for pagination purpose
 * @returns
 */
const useChatMessages = (offset = 0) => {
  const [loading, setLoading] = useState(true)
  const addOldChatMessages = useSetAtom(addOldMessagesAtom)
  const currentConvo = useAtomValue(currentConversationAtom)
  const convoStates = useAtomValue(conversationStatesAtom)
  const updateConvoHasMore = useSetAtom(updateConversationHasMoreAtom)

  useEffect(() => {
    if (!currentConvo) {
      return
    }
    const hasMore = convoStates[currentConvo._id ?? '']?.hasMore ?? true
    if (!hasMore) return

    const getMessages = async () => {
      executeSerial(DataService.GetConversationMessages, currentConvo._id).then(
        (data: any) => {
          if (!data) {
            return
          }
          const newMessages = parseMessages(data ?? [])
          addOldChatMessages(newMessages)
          updateConvoHasMore(currentConvo._id ?? '', false)
          setLoading(false)
        }
      )
    }
    getMessages()
  }, [
    offset,
    convoStates,
    addOldChatMessages,
    updateConvoHasMore,
    currentConvo,
  ])

  return {
    loading: loading,
    error: undefined,
    hasMore: convoStates[currentConvo?._id ?? '']?.hasMore ?? true,
  }
}

function parseMessages(messages: RawMessage[]): ChatMessage[] {
  const newMessages: ChatMessage[] = []
  for (const m of messages) {
    const chatMessage = toChatMessage(m)
    newMessages.push(chatMessage)
  }
  return newMessages
}

export default useChatMessages