import { Injectable, Logger } from "@nestjs/common";
import { IntegrationsService } from "../integrations/integrations.service";

export interface SenaeDeclarationResult {
  authNumber: string;
  declarationId: string;
  isStub: boolean;
  message: string;
}

/**
 * SenaeService — C-1
 * Envía la Declaración Simplificada de Importación (DSI) a la SENAE.
 * Si las credenciales de integración están configuradas, hace la llamada real.
 * Si no, genera un número de stub para entorno de desarrollo.
 *
 * Docs: §11, §18 — SENAE WebService integration
 */
@Injectable()
export class SenaeService {
  private readonly logger = new Logger(SenaeService.name);

  constructor(private integrations: IntegrationsService) {}

  async submitDSI(pkg: any, tenantId: string, category: string, agentNotes?: string): Promise<SenaeDeclarationResult> {
    const endpoint  = await this.integrations.getValue(tenantId, "senae_endpoint");
    const apiKey    = await this.integrations.getValue(tenantId, "senae_api_key");
    const ruc       = await this.integrations.getValue(tenantId, "senae_ruc");
    const agentCode = await this.integrations.getValue(tenantId, "senae_agent_code");

    const declarationId = `DSI-${pkg.trackingId}`;

    // ── Real SENAE WebService call ────────────────────────────────────────────
    if (endpoint && apiKey && ruc) {
      try {
        const payload = {
          declaracion: {
            tipo:             "DSI",
            rucDeclarante:    ruc,
            codigoAgente:     agentCode ?? null,
            trackingInterno:  pkg.trackingId,
            descripcion:      pkg.description,
            valorDeclarado:   Number(pkg.declaredValue ?? 0),
            pesoKg:           Number(pkg.actualWeight ?? pkg.declaredWeight ?? 0) * 0.453592,
            categoria:        category,
            fechaEnvio:       new Date().toISOString(),
            notas:            agentNotes ?? null,
          },
        };

        const res = await fetch(endpoint, {
          method:  "POST",
          headers: {
            "Content-Type":  "application/json",
            "Authorization": `Bearer ${apiKey}`,
            "X-Agent-Code":  agentCode ?? "",
          },
          body: JSON.stringify(payload),
          signal: AbortSignal.timeout(15_000),
        });

        if (!res.ok) {
          const errText = await res.text().catch(() => `HTTP ${res.status}`);
          this.logger.error(`[SENAE] DSI submit failed (${res.status}): ${errText}`);
          // Fall through to stub on error
        } else {
          const data = await res.json();
          const authNumber = data?.autorizacion ?? data?.authNumber ?? data?.numeroAutorizacion;
          if (authNumber) {
            this.logger.log(`[SENAE] DSI aprobada — Auth: ${authNumber} — Pkg: ${pkg.trackingId}`);
            return { authNumber, declarationId, isStub: false, message: `DSI aprobada por SENAE. Autorización: ${authNumber}` };
          }
          this.logger.warn(`[SENAE] Respuesta inesperada: ${JSON.stringify(data).slice(0, 200)}`);
        }
      } catch (err: any) {
        this.logger.error(`[SENAE] Exception: ${err.message}`);
        // Fall through to stub
      }
    } else {
      this.logger.warn(`[SENAE] Credenciales no configuradas para tenant ${tenantId} — usando stub`);
    }

    // ── Stub fallback (dev / sin credenciales) ────────────────────────────────
    const authNumber = `SENAE-DSI-${new Date().getFullYear()}-${Math.floor(100000 + Math.random() * 900000)}`;
    this.logger.warn(`[SENAE STUB] Auth: ${authNumber} — configure senae_endpoint, senae_api_key, senae_ruc en Integraciones`);
    return {
      authNumber,
      declarationId,
      isStub: true,
      message: `DSI generada (STUB — sin conexión real SENAE). Auth: ${authNumber}. Configure las claves SENAE en Admin → Integraciones.`,
    };
  }
}