import axios from 'axios'
import { getAccessToken } from '../../get-access-token'
import {
  ChatBotConstructorParams,
  ChatApiResponseBodyBase,
  ChatMessageBase,
  ChatParamsBase,
  ChatBotConfigBase
} from './types'

abstract class ChatBotBase<
  ChatMessage extends ChatMessageBase,
  ChatApiResponseBody extends ChatApiResponseBodyBase,
  ChatBotConfig extends Pick<ChatBotConfigBase, 'stream'>
  > {

  private apiKey: string
  private secretKey: string
  private accessToken: string

  private botConfig: ChatBotConfig


  protected abstract getDefaultConfig(): ChatBotConfig

  protected abstract getApiUrl():Promise<string>

  protected async getAccessToken():Promise<string> {
    if (!this.accessToken) {
      const accessTokenInfo = await getAccessToken({AK: this.apiKey, SK: this.secretKey})
      this.accessToken = accessTokenInfo?.access_token
    }
    return this.accessToken
  }

  protected constructor(params: ChatBotConstructorParams) {
    const {AK: apiKey, SK: secretKey } = params
    this.apiKey = apiKey
    this.secretKey = secretKey
    this.botConfig = this.getDefaultConfig()
  }

  public config (params: ChatBotConfig): this {
    this.botConfig = {
      ...this.botConfig,
      ...params
    }
    return this
  }

  public async chat(params: ChatParamsBase<ChatMessage> & ChatBotConfig ): Promise<ChatApiResponseBody> {
    const { messages, ...config } = params
    const currentConfig: ChatBotConfig = {
      ...this.botConfig,
      ...config
    }
    const res = await axios.post<ChatApiResponseBody>(
      await this.getApiUrl(),
      {
        messages,
      },
      {
        headers: {
          'Content-Type': 'application/json'
        },
        responseType: currentConfig.stream ? 'stream': 'json'
      }
    )
    const {data} = res
    return data
  }
}

export {
  ChatBotBase
}