feat: add Exotel webhook controller and service for call event parsing

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/ai/ai-enrichment.service.ts

@@ -0,0 +1,113 @@
+import { Injectable, Logger } from '@nestjs/common';
+import { ConfigService } from '@nestjs/config';
+import Anthropic from '@anthropic-ai/sdk';
+
+type LeadContext = {
+    firstName?: string;
+    lastName?: string;
+    leadSource?: string;
+    interestedService?: string;
+    leadStatus?: string;
+    contactAttempts?: number;
+    createdAt?: string;
+    campaignId?: string;
+    activities?: { activityType: string; summary: string }[];
+};
+
+type EnrichmentResult = {
+    aiSummary: string;
+    aiSuggestedAction: string;
+};
+
+@Injectable()
+export class AiEnrichmentService {
+    private readonly logger = new Logger(AiEnrichmentService.name);
+    private client: Anthropic | null = null;
+
+    constructor(private config: ConfigService) {
+        const apiKey = config.get<string>('ai.anthropicApiKey');
+        if (apiKey) {
+            this.client = new Anthropic({ apiKey });
+        } else {
+            this.logger.warn('ANTHROPIC_API_KEY not set — AI enrichment disabled, using fallback');
+        }
+    }
+
+    async enrichLead(lead: LeadContext): Promise<EnrichmentResult> {
+        // Fallback if no API key configured
+        if (!this.client) {
+            return this.fallbackEnrichment(lead);
+        }
+
+        try {
+            const daysSince = lead.createdAt
+                ? Math.floor((Date.now() - new Date(lead.createdAt).getTime()) / (1000 * 60 * 60 * 24))
+                : 0;
+
+            const activitiesText = lead.activities?.length
+                ? lead.activities.map(a => `- ${a.activityType}: ${a.summary}`).join('\n')
+                : 'No previous interactions';
+
+            const prompt = `You are an AI assistant for a hospital call center at Global Hospital.
+An inbound call is coming in from a lead. Summarize their history and suggest what the call center agent should do.
+
+Lead details:
+- Name: ${lead.firstName ?? 'Unknown'} ${lead.lastName ?? ''}
+- Source: ${lead.leadSource ?? 'Unknown'}
+- Interested in: ${lead.interestedService ?? 'Unknown'}
+- Current status: ${lead.leadStatus ?? 'Unknown'}
+- Lead age: ${daysSince} days
+- Contact attempts: ${lead.contactAttempts ?? 0}
+
+Recent activity:
+${activitiesText}
+
+Respond ONLY with valid JSON (no markdown, no code blocks):
+{"aiSummary": "1-2 sentence summary of who this lead is and their history", "aiSuggestedAction": "5-10 word suggested action for the agent"}`;
+
+            const response = await this.client.messages.create({
+                model: 'claude-haiku-4-5-20251001',
+                max_tokens: 200,
+                messages: [{ role: 'user', content: prompt }],
+            });
+
+            const text = response.content[0].type === 'text' ? response.content[0].text : '';
+            const parsed = JSON.parse(text.trim());
+
+            this.logger.log(`AI enrichment generated for lead ${lead.firstName} ${lead.lastName}`);
+            return {
+                aiSummary: parsed.aiSummary,
+                aiSuggestedAction: parsed.aiSuggestedAction,
+            };
+        } catch (error) {
+            this.logger.error(`AI enrichment failed: ${error}`);
+            return this.fallbackEnrichment(lead);
+        }
+    }
+
+    private fallbackEnrichment(lead: LeadContext): EnrichmentResult {
+        const daysSince = lead.createdAt
+            ? Math.floor((Date.now() - new Date(lead.createdAt).getTime()) / (1000 * 60 * 60 * 24))
+            : 0;
+
+        const attempts = lead.contactAttempts ?? 0;
+        const service = lead.interestedService ?? 'general inquiry';
+        const source = lead.leadSource?.replace(/_/g, ' ').toLowerCase() ?? 'unknown source';
+
+        let summary: string;
+        let action: string;
+
+        if (attempts === 0) {
+            summary = `First-time inquiry from ${source}. Interested in ${service}. Lead is ${daysSince} day(s) old with no previous contact.`;
+            action = `Introduce services and offer appointment booking`;
+        } else if (attempts === 1) {
+            summary = `Returning inquiry — contacted once before. Interested in ${service} via ${source}. Lead is ${daysSince} day(s) old.`;
+            action = `Follow up on previous conversation, offer appointment`;
+        } else {
+            summary = `Repeat contact (${attempts} previous attempts) for ${service}. Originally from ${source}, ${daysSince} day(s) old. Shows high interest.`;
+            action = `Prioritize appointment booking — high-intent lead`;
+        }
+
+        return { aiSummary: summary, aiSuggestedAction: action };
+    }
+}