chore: add ai service

2025-07-23 17:00:47 +03:30
parent 95ed0605bb
commit f42280846c
19 changed files with 1030 additions and 652 deletions
@@ -0,0 +1,162 @@
+import { BadRequestException, Injectable, NotFoundException } from "@nestjs/common";
+import { firstValueFrom } from "rxjs";
+
+import { AiService } from "./ai.service";
+import { AiMessage } from "../../../common/enums/message.enum";
+import { MessageDetails } from "../../mail-server/interfaces/messages-response.interface";
+import { WildDuckMessagesService } from "../../mail-server/services/wildduck-messages.service";
+import { SummarizeEmailDto } from "../DTO/summarize-email.dto";
+import { WriteEmailAssistanceDto } from "../DTO/write-email-assistance.dto";
+import { SummaryLength, SummaryTone } from "../enums/ai.enum";
+import { EmailData, SummarizationOptions, WritingAssistanceOptions } from "../interfaces/ai-service.interface";
+
+@Injectable()
+export class AiAssistantService {
+  constructor(
+    private readonly messagesService: WildDuckMessagesService,
+    private readonly aiService: AiService,
+  ) {}
+
+  //************************************************* */
+  async summarizeEmail(summarizeDto: SummarizeEmailDto, userId: string) {
+    const message = await firstValueFrom(this.messagesService.getMessage(userId, summarizeDto.mailbox, summarizeDto.messageId));
+
+    if (!message) throw new NotFoundException(AiMessage.MESSAGE_NOT_FOUND_OR_ACCESS_DENIED);
+
+    const emailData = this.extractEmailData(message);
+
+    const summary = await this.generateEmailSummary(emailData, summarizeDto.length, summarizeDto.tone);
+
+    return summary;
+  }
+
+  //************************************************* */
+  async assistEmailWriting(writeAssistanceDto: WriteEmailAssistanceDto, userId: string) {
+    const assistance = await this.generateEmailWritingAssistance(writeAssistanceDto, userId);
+
+    return assistance;
+  }
+
+  //************************************************* */
+  private extractEmailData(message: MessageDetails) {
+    return {
+      subject: message.subject,
+      content: this.extractTextContent(message),
+      htmlContent: this.extractHtmlContent(message),
+      from: this.extractSenderInfo(message),
+      to: this.extractRecipientInfo(message),
+      date: message.date || new Date(),
+      attachments: message.attachments || [],
+    };
+  }
+
+  //************************************************* */
+  private extractTextContent(message: MessageDetails): string {
+    if (message.text) {
+      return typeof message.text === "string" ? message.text : message.text || "";
+    }
+
+    if (message.html) {
+      return this.stripHtmlTags(typeof message.html === "string" ? message.html : message.html[0] || "");
+    }
+
+    return "";
+  }
+
+  //************************************************* */
+  private extractHtmlContent(message: MessageDetails): string {
+    if (message.html) {
+      return typeof message.html === "string" ? message.html : message.html[0] || "";
+    }
+    return "";
+  }
+
+  //************************************************* */
+  private extractSenderInfo(message: MessageDetails): string {
+    if (message.from && message.from.address) {
+      return message.from.name ? `${message.from.name} <${message.from.address}>` : message.from.address;
+    }
+    return "";
+  }
+
+  //************************************************* */
+  private extractRecipientInfo(message: MessageDetails): string[] {
+    const recipients: string[] = [];
+
+    if (message.to && Array.isArray(message.to)) {
+      recipients.push(...message.to.map((recipient) => (recipient.name ? `${recipient.name} <${recipient.address}>` : recipient.address)));
+    }
+
+    return recipients;
+  }
+
+  //************************************************* */
+  private stripHtmlTags(html: string): string {
+    return html
+      .replace(/<[^>]*>/g, "")
+      .replace(/&nbsp;/g, " ")
+      .trim();
+  }
+
+  //************************************************* */
+  private async generateEmailSummary(emailData: any, length: SummaryLength = SummaryLength.MEDIUM, _tone: SummaryTone = SummaryTone.PROFESSIONAL) {
+    const content = emailData.content || emailData.htmlContent;
+
+    if (!content.trim()) throw new BadRequestException(AiMessage.EMAIL_CONTENT_IS_EMPTY_OR_COULD_NOT_BE_EXTRACTED);
+
+    const aiEmailData: EmailData = {
+      subject: emailData.subject,
+      content: emailData.content,
+      htmlContent: emailData.htmlContent,
+      from: emailData.from,
+      to: emailData.to,
+      date: emailData.date,
+      attachments: emailData.attachments,
+    };
+
+    const summarizationOptions: SummarizationOptions = {
+      length: length.toLowerCase() as "short" | "medium" | "detailed",
+      tone: _tone.toLowerCase() as "formal" | "casual" | "professional",
+    };
+
+    const aiResponse = await this.aiService.summarizeEmail(aiEmailData, summarizationOptions);
+
+    return {
+      summary: aiResponse.summary,
+      keyPoints: aiResponse.keyPoints,
+      suggestedActions: aiResponse.suggestedActions,
+      priority: aiResponse.priority,
+      sentiment: aiResponse.sentiment,
+    };
+  }
+
+  //************************************************* */
+  private async generateEmailWritingAssistance(writeAssistanceDto: WriteEmailAssistanceDto, _userId: string) {
+    const writingOptions: WritingAssistanceOptions = {
+      purpose: writeAssistanceDto.purpose.toLowerCase() as "reply" | "forward" | "new" | "follow_up",
+      tone: (writeAssistanceDto.tone?.toLowerCase() as "formal" | "casual" | "professional" | "friendly" | "urgent") || "professional",
+      length: (writeAssistanceDto.length?.toLowerCase() as "short" | "medium" | "long") || "medium",
+      keyPoints: writeAssistanceDto.keyPoints,
+      context: writeAssistanceDto.context
+        ? {
+            originalContent: writeAssistanceDto.context.originalContent,
+            originalSender: writeAssistanceDto.context.originalSender,
+            originalSubject: writeAssistanceDto.context.originalSubject,
+          }
+        : undefined,
+      additionalInstructions: writeAssistanceDto.additionalInstructions,
+    };
+
+    const aiResponse = await this.aiService.assistEmailWriting(writeAssistanceDto.mainMessage, writingOptions);
+
+    return {
+      suggestion: {
+        subject: aiResponse.subject,
+        content: aiResponse.content,
+        alternatives: aiResponse.alternatives,
+      },
+      tips: aiResponse.tips,
+      improvements: aiResponse.improvements,
+    };
+  }
+}