import { Injectable, Logger, OnModuleInit } from '@nestjs/common';
import { ConfigService } from '@nestjs/config';
import { generateObject } from 'ai';
import { z } from 'zod';
import { EventBusService } from '../event-bus.service';
import { Topics } from '../event-types';
import type { CallCompletedEvent } from '../event-types';
import { PlatformGraphqlService } from '../../platform/platform-graphql.service';
import { createAiModel } from '../../ai/ai-provider';
import type { LanguageModel } from 'ai';
import { AiConfigService } from '../../config/ai-config.service';

@Injectable()
export class AiInsightConsumer implements OnModuleInit {
    private readonly logger = new Logger(AiInsightConsumer.name);
    private readonly aiModel: LanguageModel | null;

    constructor(
        private eventBus: EventBusService,
        private platform: PlatformGraphqlService,
        private config: ConfigService,
        private aiConfig: AiConfigService,
    ) {
        const cfg = aiConfig.getConfig();
        this.aiModel = createAiModel({
            provider: cfg.provider,
            model: cfg.model,
            anthropicApiKey: config.get<string>('ai.anthropicApiKey'),
            openaiApiKey: config.get<string>('ai.openaiApiKey'),
        });
    }

    onModuleInit() {
        this.eventBus.on(Topics.CALL_COMPLETED, (event: CallCompletedEvent) => this.handleCallCompleted(event));
    }

    private async handleCallCompleted(event: CallCompletedEvent): Promise<void> {
        if (!event.leadId) {
            this.logger.debug('[AI-INSIGHT] No leadId — skipping');
            return;
        }

        if (!this.aiModel) {
            this.logger.debug('[AI-INSIGHT] No AI model configured — skipping');
            return;
        }

        this.logger.log(`[AI-INSIGHT] Generating insight for lead ${event.leadId}`);

        try {
            // Fetch lead + all activities
            const data = await this.platform.query<any>(
                `{ leads(filter: { id: { eq: "${event.leadId}" } }) { edges { node {
                    id name contactName { firstName lastName }
                    status source interestedService
                    contactAttempts lastContacted
                } } } }`,
            );
            const lead = data?.leads?.edges?.[0]?.node;
            if (!lead) return;

            const activityData = await this.platform.query<any>(
                `{ leadActivities(first: 20, filter: { leadId: { eq: "${event.leadId}" } }, orderBy: [{ occurredAt: DescNullsLast }]) {
                    edges { node { activityType summary occurredAt channel durationSec outcome } }
                } }`,
            );
            const activities = activityData?.leadActivities?.edges?.map((e: any) => e.node) ?? [];

            const leadName = lead.contactName
                ? `${lead.contactName.firstName ?? ''} ${lead.contactName.lastName ?? ''}`.trim()
                : lead.name ?? 'Unknown';

            // Build context
            const activitySummary = activities.map((a: any) =>
                `${a.activityType}: ${a.summary} (${a.occurredAt ?? 'unknown date'})`,
            ).join('\n');

            // Generate insight
            const { object } = await generateObject({
                model: this.aiModel,
                schema: z.object({
                    summary: z.string().describe('2-3 sentence summary of this lead based on all their interactions'),
                    suggestedAction: z.string().describe('One clear next action for the agent'),
                }),
                system: this.aiConfig.renderPrompt('callInsight', {
                    hospitalName: process.env.HOSPITAL_NAME ?? 'the hospital',
                }),
                prompt: `Lead: ${leadName}
Status: ${lead.status ?? 'Unknown'}
Source: ${lead.source ?? 'Unknown'}
Interested in: ${lead.interestedService ?? 'Not specified'}
Contact attempts: ${lead.contactAttempts ?? 0}
Last contacted: ${lead.lastContacted ?? 'Never'}

Recent activity (newest first):
${activitySummary || 'No activity recorded'}

Latest call:
- Direction: ${event.direction}
- Duration: ${event.durationSec}s
- Disposition: ${event.disposition}
- Notes: ${event.notes ?? 'None'}`,
                maxOutputTokens: 200,
            });

            // Update lead with new AI insight
            await this.platform.query<any>(
                `mutation($id: UUID!, $data: LeadUpdateInput!) { updateLead(id: $id, data: $data) { id } }`,
                {
                    id: event.leadId,
                    data: {
                        aiSummary: object.summary,
                        aiSuggestedAction: object.suggestedAction,
                        lastContacted: new Date().toISOString(),
                        contactAttempts: (lead.contactAttempts ?? 0) + 1,
                    },
                },
            );

            this.logger.log(`[AI-INSIGHT] Updated lead ${event.leadId}: "${object.summary.substring(0, 60)}..."`);
        } catch (err: any) {
            this.logger.error(`[AI-INSIGHT] Failed for lead ${event.leadId}: ${err.message}`);
        }
    }
}