import { Router } from "express";
import { pool } from "../db.js";

const router = Router();

/**
 * List all telecom entities for a customer.
 *
 * GET /api/v1/entities/telecom?customer_id=123
 * GET /api/v1/entities/telecom?email=user@example.com
 */
router.get("/api/v1/entities/telecom", async (req, res) => {
  const { customer_id, email } = req.query;

  if (!customer_id && !email) {
    res.status(400).json({ error: "Provide customer_id or email." });
    return;
  }

  try {
    let query: string;
    let params: any[];

    if (customer_id) {
      query = "SELECT * FROM telecom_entities WHERE customer_id = $1 AND active = true ORDER BY jurisdiction, legal_name";
      params = [customer_id];
    } else {
      query = `SELECT te.* FROM telecom_entities te
               JOIN customers c ON c.id = te.customer_id
               WHERE c.email = $1 AND te.active = true
               ORDER BY te.jurisdiction, te.legal_name`;
      params = [(email as string).toLowerCase().trim()];
    }

    const result = await pool.query(query, params);

    res.json({
      entities: result.rows,
      count: result.rows.length,
    });
  } catch (err) {
    console.error("[telecom-entities] List error:", err);
    res.status(500).json({ error: "Could not fetch entities." });
  }
});

/**
 * Get a single telecom entity by ID.
 *
 * GET /api/v1/entities/telecom/:id
 */
router.get("/api/v1/entities/telecom/:id", async (req, res) => {
  try {
    const result = await pool.query("SELECT * FROM telecom_entities WHERE id = $1", [req.params.id]);
    if (result.rows.length === 0) {
      res.status(404).json({ error: "Entity not found." });
      return;
    }
    res.json(result.rows[0]);
  } catch (err) {
    console.error("[telecom-entities] Get error:", err);
    res.status(500).json({ error: "Could not fetch entity." });
  }
});

/**
 * Create a new telecom entity.
 *
 * POST /api/v1/entities/telecom
 */
router.post("/api/v1/entities/telecom", async (req, res) => {
  const {
    customer_id, customer_email,
    jurisdiction, legal_name, dba_name, ein,
    // FCC
    frn, filer_id_499,
    // CRTC
    incorporation_number, incorporation_province, crtc_registration_number,
    // Classification
    filer_type, infra_type, is_deminimis, is_lire, service_categories,
    // Contact
    contact_name, contact_email, contact_phone, ceo_name, ceo_title,
    // Address
    address_street, address_city, address_state, address_zip,
    // Revenue
    last_filing_year, total_revenue_cents, interstate_pct, international_pct,
  } = req.body ?? {};

  if (!legal_name) {
    res.status(400).json({ error: "legal_name is required." });
    return;
  }

  // Resolve customer_id from email if needed
  let resolvedCustomerId = customer_id;
  if (!resolvedCustomerId && customer_email) {
    const cust = await pool.query("SELECT id FROM customers WHERE email = $1", [customer_email.toLowerCase().trim()]);
    if (cust.rows.length > 0) {
      resolvedCustomerId = cust.rows[0].id;
    }
  }

  try {
    const result = await pool.query(
      `INSERT INTO telecom_entities (
        customer_id, jurisdiction, legal_name, dba_name, ein,
        frn, filer_id_499,
        incorporation_number, incorporation_province, crtc_registration_number,
        filer_type, infra_type, is_deminimis, is_lire, service_categories,
        contact_name, contact_email, contact_phone, ceo_name, ceo_title,
        address_street, address_city, address_state, address_zip,
        last_filing_year, total_revenue_cents, interstate_pct, international_pct
      ) VALUES ($1,$2,$3,$4,$5,$6,$7,$8,$9,$10,$11,$12,$13,$14,$15,$16,$17,$18,$19,$20,$21,$22,$23,$24,$25,$26,$27,$28)
      RETURNING *`,
      [
        resolvedCustomerId || null,
        jurisdiction || "FCC",
        legal_name, dba_name || null, ein || null,
        frn || null, filer_id_499 || null,
        incorporation_number || null, incorporation_province || null, crtc_registration_number || null,
        filer_type || null, infra_type || null,
        is_deminimis === true, is_lire === true,
        service_categories || null,
        contact_name || null, contact_email || null, contact_phone || null,
        ceo_name || null, ceo_title || null,
        address_street || null, address_city || null, address_state || null, address_zip || null,
        last_filing_year || null, total_revenue_cents || 0,
        interstate_pct || 0, international_pct || 0,
      ],
    );

    res.status(201).json(result.rows[0]);
  } catch (err) {
    console.error("[telecom-entities] Create error:", err);
    res.status(500).json({ error: "Could not create entity." });
  }
});

/**
 * Update a telecom entity.
 *
 * PATCH /api/v1/entities/telecom/:id
 */
router.patch("/api/v1/entities/telecom/:id", async (req, res) => {
  const id = req.params.id;
  const updates = req.body ?? {};

  // Build dynamic SET clause from provided fields
  const allowedFields = [
    "legal_name", "dba_name", "ein", "jurisdiction",
    "frn", "filer_id_499",
    "incorporation_number", "incorporation_province", "crtc_registration_number",
    "filer_type", "infra_type", "is_deminimis", "is_lire", "service_categories",
    "contact_name", "contact_email", "contact_phone", "ceo_name", "ceo_title",
    "address_street", "address_city", "address_state", "address_zip",
    "last_filing_year", "total_revenue_cents", "interstate_pct", "international_pct",
    "active", "notes",
    // Carrier classification (migration 043)
    "carrier_category", "is_wholesale", "is_gateway_provider",
    "is_international_only", "uses_ucaas_provider", "carrier_metadata",
    "stir_shaken_status", "stir_shaken_cert_authority",
    "upstream_provider_name", "upstream_provider_frn",
    "rmd_letter_minio_path", "rmd_letter_generated_at", "last_compliance_checkup",
    // FACS (Foreign Adversary Control System) fields (migration 045)
    "facs_schedule", "facs_has_foreign_adversary", "facs_filing_status",
    "facs_ownership_data", "covered_authorizations", "has_section_214",
    "facs_filed_at",
    // Form 499-A Block 1/2 fidelity (migrations 048, 054)
    "affiliated_filer_name", "affiliated_filer_ein", "management_company_name",
    "trade_names",
    "regulatory_contact_name", "regulatory_contact_email", "regulatory_contact_phone",
    "worksheet_office_company", "worksheet_office_street", "worksheet_office_city",
    "worksheet_office_state", "worksheet_office_zip",
    "billing_contact_name", "billing_contact_email", "itsp_regulatory_fee_email",
    "dc_agent_company", "dc_agent_street", "dc_agent_city", "dc_agent_state",
    "dc_agent_zip", "dc_agent_phone", "dc_agent_email",
    "officer_1_street", "officer_1_city", "officer_1_state", "officer_1_zip",
    "officer_2_name", "officer_2_title", "officer_2_street", "officer_2_city",
    "officer_2_state", "officer_2_zip",
    "officer_3_name", "officer_3_title", "officer_3_street", "officer_3_city",
    "officer_3_state", "officer_3_zip",
    "officer_count_claimed", "entity_structure",
    "jurisdictions_served",
    "first_telecom_service_year", "first_telecom_service_month",
    "first_telecom_service_pre_1999",
    // Form 499-A Block 6 fidelity (migrations 048, 054)
    "exempt_usf", "exempt_trs", "exempt_nanpa", "exempt_lnp", "exempt_itsp",
    "exemption_explanation",
    "is_state_local_gov", "is_tax_exempt_501c",
    "nondisclosure_requested",
    // Line 105 taxonomy (migration 053)
    "line_105_primary", "line_105_categories",
    "wireless_meta", "satellite_meta", "audio_bridging_meta", "private_line_circuits",
    // Safe harbor election (migration 054)
    "safe_harbor_election",
    // CORES + CALEA + foreign carrier (migration 052)
    "cores_username", "cores_password_hash", "cores_registered_at",
    "calea_ssi_generated_at", "calea_ssi_reviewer_name", "calea_ssi_next_review_date",
    "foreign_affiliations",
    // NECA OCN (migration 048)
    "ocn", "ocn_category", "ocn_assigned_at",
  ];

  const sets: string[] = [];
  const values: any[] = [];
  let paramIdx = 1;

  for (const field of allowedFields) {
    if (field in updates) {
      sets.push(`${field} = $${paramIdx}`);
      values.push(updates[field]);
      paramIdx++;
    }
  }

  if (sets.length === 0) {
    res.status(400).json({ error: "No valid fields to update." });
    return;
  }

  sets.push(`updated_at = NOW()`);
  values.push(id);

  try {
    const result = await pool.query(
      `UPDATE telecom_entities SET ${sets.join(", ")} WHERE id = $${paramIdx} RETURNING *`,
      values,
    );

    if (result.rows.length === 0) {
      res.status(404).json({ error: "Entity not found." });
      return;
    }

    res.json(result.rows[0]);
  } catch (err) {
    console.error("[telecom-entities] Update error:", err);
    res.status(500).json({ error: "Could not update entity." });
  }
});

/**
 * Classify a telecom entity's carrier type.
 *
 * PATCH /api/v1/entities/telecom/:id/classify
 *
 * Accepts the full carrier classification from the questionnaire and
 * validates field combinations (e.g. UCaaS provider requires metadata).
 */
router.patch("/api/v1/entities/telecom/:id/classify", async (req, res) => {
  const id = req.params.id;
  const body = req.body ?? {};

  // Validate carrier_category
  const validCategories = [
    "interconnected_voip", "non_interconnected_voip", "clec", "ixc", "cmrs", "other",
  ];
  if (body.carrier_category && !validCategories.includes(body.carrier_category)) {
    res.status(400).json({ error: `Invalid carrier_category. Must be one of: ${validCategories.join(", ")}` });
    return;
  }

  // Validate stir_shaken_status
  const validStirShaken = [
    "complete_implementation", "partial_implementation",
    "robocall_mitigation_only", "exempt_small_carrier", "not_applicable",
  ];
  if (body.stir_shaken_status && !validStirShaken.includes(body.stir_shaken_status)) {
    res.status(400).json({ error: `Invalid stir_shaken_status. Must be one of: ${validStirShaken.join(", ")}` });
    return;
  }

  // Validate UCaaS metadata
  if (body.uses_ucaas_provider === true) {
    const meta = body.carrier_metadata ?? {};
    if (!meta.ucaas_provider) {
      res.status(400).json({ error: "carrier_metadata.ucaas_provider is required when uses_ucaas_provider is true." });
      return;
    }
  }

  // Validate gateway metadata
  if (body.is_gateway_provider === true) {
    const meta = body.carrier_metadata ?? {};
    if (!meta.gateway_countries || !Array.isArray(meta.gateway_countries) || meta.gateway_countries.length === 0) {
      res.status(400).json({ error: "carrier_metadata.gateway_countries is required when is_gateway_provider is true." });
      return;
    }
  }

  // Validate complete STIR/SHAKEN requires cert authority
  if (body.stir_shaken_status === "complete_implementation" && !body.stir_shaken_cert_authority) {
    res.status(400).json({ error: "stir_shaken_cert_authority is required for complete_implementation." });
    return;
  }

  // Build update
  const classifyFields = [
    "carrier_category", "is_wholesale", "is_gateway_provider",
    "is_international_only", "uses_ucaas_provider", "carrier_metadata",
    "stir_shaken_status", "stir_shaken_cert_authority",
    "upstream_provider_name", "upstream_provider_frn",
    // Also allow updating infra_type since the questionnaire captures it
    "infra_type",
  ];

  const sets: string[] = [];
  const values: any[] = [];
  let paramIdx = 1;

  for (const field of classifyFields) {
    if (field in body) {
      if (field === "carrier_metadata") {
        sets.push(`${field} = $${paramIdx}::jsonb`);
      } else {
        sets.push(`${field} = $${paramIdx}`);
      }
      values.push(body[field]);
      paramIdx++;
    }
  }

  if (sets.length === 0) {
    res.status(400).json({ error: "No classification fields provided." });
    return;
  }

  sets.push(`updated_at = NOW()`);
  values.push(id);

  try {
    const result = await pool.query(
      `UPDATE telecom_entities SET ${sets.join(", ")} WHERE id = $${paramIdx} RETURNING *`,
      values,
    );

    if (result.rows.length === 0) {
      res.status(404).json({ error: "Entity not found." });
      return;
    }

    res.json(result.rows[0]);
  } catch (err) {
    console.error("[telecom-entities] Classify error:", err);
    res.status(500).json({ error: "Could not classify entity." });
  }
});

/**
 * Run compliance check against a specific entity.
 *
 * GET /api/v1/entities/telecom/:id/compliance
 *
 * Uses the entity's FRN to run the same checks as /api/v1/fcc/lookup,
 * enriched with entity-specific data (classification, filing history).
 */
router.get("/api/v1/entities/telecom/:id/compliance", async (req, res) => {
  try {
    const entity = await pool.query("SELECT * FROM telecom_entities WHERE id = $1", [req.params.id]);
    if (entity.rows.length === 0) {
      res.status(404).json({ error: "Entity not found." });
      return;
    }

    const e = entity.rows[0];

    if (e.jurisdiction === "FCC" && e.frn) {
      // Proxy to the FCC lookup endpoint
      const lookupUrl = `http://localhost:${process.env.PORT || 3001}/api/v1/fcc/lookup?frn=${e.frn}`;
      const lookupResp = await fetch(lookupUrl, { signal: AbortSignal.timeout(30000) });
      const lookupData = await lookupResp.json() as Record<string, unknown>;

      res.json(Object.assign({
        entity: {
          id: e.id,
          legal_name: e.legal_name,
          jurisdiction: e.jurisdiction,
          frn: e.frn,
          filer_type: e.filer_type,
          is_deminimis: e.is_deminimis,
          is_lire: e.is_lire,
        },
      }, lookupData));
    } else if (e.jurisdiction === "CRTC") {
      // CRTC compliance checks (simplified)
      const now = new Date();
      const checks = [
        {
          id: "crtc_registration",
          label: "CRTC Registration",
          status: e.crtc_registration_number ? "green" : "unknown",
          detail: e.crtc_registration_number
            ? `Registered: ${e.crtc_registration_number}`
            : "Registration number not on file",
          action_url: null,
          due_date: null,
        },
        {
          id: "provincial_incorporation",
          label: `${e.incorporation_province || "Provincial"} Incorporation`,
          status: e.incorporation_number ? "green" : "unknown",
          detail: e.incorporation_number
            ? `${e.incorporation_province} #${e.incorporation_number}`
            : "Incorporation number not on file",
          action_url: null,
          due_date: null,
        },
      ];

      res.json({
        entity: {
          id: e.id,
          legal_name: e.legal_name,
          jurisdiction: e.jurisdiction,
          incorporation_number: e.incorporation_number,
          incorporation_province: e.incorporation_province,
        },
        checks,
        checked_at: new Date().toISOString(),
      });
    } else {
      res.json({
        entity: { id: e.id, legal_name: e.legal_name, jurisdiction: e.jurisdiction },
        checks: [],
        note: "No FRN on file — add an FRN to run FCC compliance checks.",
        checked_at: new Date().toISOString(),
      });
    }
  } catch (err) {
    console.error("[telecom-entities] Compliance check error:", err);
    res.status(500).json({ error: "Compliance check failed." });
  }
});

export default router;