doneit-web/src/app/module/chat/domain/use-case/message-attachment-by-message-id.service.ts

import { Injectable } from '@angular/core';
import { z } from 'zod';
import { AttachmentRemoteDataSourceService } from 'src/app/module/chat/data/data-source/attachment/attachment-remote-data-source.service'
import { AttachmentLocalDataSource } from 'src/app/module/chat/data/data-source/attachment/attachment-local-data-source.service'
import { convertBlobToDataURL } from 'src/app/utils/ToBase64';
import { Result } from 'neverthrow';
import { Logger } from 'src/app/services/logger/main/service';

const MessageAttachmentByMessageIdSchema = z.object({
  $messageId: z.number(),
  id: z.string()
})

export type MessageAttachmentByMessageIdInput = z.infer<typeof MessageAttachmentByMessageIdSchema>

@Injectable({
  providedIn: 'root'
})
export class MessageAttachmentByMessageIdUseCase {

  constructor(
    private AttachmentRemoteDataSourceService: AttachmentRemoteDataSourceService,
    private AttachmentLocalDataSource: AttachmentLocalDataSource
  ) { }

  async execute(input: MessageAttachmentByMessageIdInput): Promise<Result<string, any>> {

    const getLocalAttachment = await this.AttachmentLocalDataSource.findOne({
      $messageId: input.$messageId
    })

    if(getLocalAttachment.isOk() && getLocalAttachment.value) {
      if(getLocalAttachment.value) {
        return getLocalAttachment.map(e => e.file)
      }
    } else {
      const result = await this.AttachmentRemoteDataSourceService.getAttachment(input.id)
      return result.asyncMap(async (e) => {

        const dataUrl = await convertBlobToDataURL(e)
        Logger.info('downloaded file', {
          data: dataUrl.slice(0, 100)+'...'
        })

        this.AttachmentLocalDataSource.insert({
          $messageId: input.$messageId,
          id: input.id,
          file: dataUrl
        })

        return dataUrl
      })
    }

  }
}