// ============================================
// AI Layer — Performance Strategist
// ============================================

import { getAIClient } from './client';
import type { AccountOverview, CampaignWithInsights } from '@/lib/meta/types';

export interface StrategicAnalysis {
  summary: string;
  top_performers: string[];
  issues: string[];
  recommendations: string[];
  suggested_actions: SuggestedAction[];
}

export interface SuggestedAction {
  campaign_id: string;
  campaign_name: string;
  action: 'pause' | 'increase_budget' | 'reduce_budget' | 'create_variation';
  reason: string;
  priority: 'high' | 'medium' | 'low';
}

export async function analyzePerformance(
  overview: AccountOverview,
  campaigns: CampaignWithInsights[]
): Promise<StrategicAnalysis> {
  const client = getAIClient();

  const campaignSummary = campaigns.map((c) => {
    const ins = c.insights as any;
    return {
      id: c.campaign.id,
      name: c.campaign.name,
      status: c.campaign.status,
      objective: c.campaign.objective,
      daily_budget: `R$${(parseInt(c.campaign.daily_budget || '0', 10) / 100).toFixed(2)}`,
      spend: `R$${parseFloat(ins?.spend || '0').toFixed(2)}`,
      ctr: `${parseFloat(ins?.ctr || '0').toFixed(2)}%`,
      cpc: `R$${parseFloat(ins?.cpc || '0').toFixed(2)}`,
      cpm: `R$${parseFloat(ins?.cpm || '0').toFixed(2)}`,
      leads: ins?.leads || 0,
      purchases: ins?.purchases || 0,
      roas: ins?.roas ? ins.roas.toFixed(2) : '0',
    };
  });

  const response = await client.chat.completions.create({
    model: 'gpt-4o',
    temperature: 0.4,
    response_format: { type: 'json_object' },
    messages: [
      {
        role: 'system',
        content: `Você é um estrategista de mídia paga expert em Facebook Ads.
Analise os dados de performance e forneça insights acionáveis.

Retorne um JSON com:
- "summary": resumo geral da performance em 2-3 frases (pt-BR)
- "top_performers": array de strings com os nomes das melhores campanhas e por quê
- "issues": array de strings com problemas identificados
- "recommendations": array de strings com recomendações estratégicas
- "suggested_actions": array de objetos com:
  - "campaign_id": ID da campanha
  - "campaign_name": nome
  - "action": "pause" | "increase_budget" | "reduce_budget" | "create_variation"
  - "reason": motivo da sugestão
  - "priority": "high" | "medium" | "low"

Seja direto, use dados específicos, e foque em ROI.`,
      },
      {
        role: 'user',
        content: `Analise a performance das campanhas:

OVERVIEW DA CONTA:
- Gasto Total: R$${overview.total_spend.toFixed(2)}
- Total Leads: ${overview.total_leads}
- ROAS Médio: ${overview.total_roas.toFixed(2)}x
- CTR Médio: ${overview.avg_ctr.toFixed(2)}%
- CPC Médio: R$${overview.avg_cpc.toFixed(2)}
- CPM Médio: R$${overview.avg_cpm.toFixed(2)}
- Campanhas Ativas: ${overview.campaigns_active}
- Campanhas Pausadas: ${overview.campaigns_paused}

CAMPANHAS DETALHADAS:
${JSON.stringify(campaignSummary, null, 2)}`,
      },
    ],
  });

  const content = response.choices[0]?.message?.content;
  if (!content) throw new Error('Empty response from AI');

  return JSON.parse(content) as StrategicAnalysis;
}