'use strict';

const express = require('express');
const router = express.Router();
const pool = require('../db');
const { db } = require('../activityDb');
const { sendMail } = require('../utils/mailer');

// ─── SIGNATURES ────────────────────────────────────────────────────────────────

// GET /api/email/signatures — list signatures for a given agent
router.get('/signatures', (req, res) => {
  try {
    const { agent_id } = req.query;
    if (!agent_id) return res.status(400).json({ error: 'agent_id è obbligatorio' });

    const rows = db.prepare(`
      SELECT id, name, body_html, is_default, created_at, updated_at
      FROM email_signatures
      WHERE agent_id = ?
      ORDER BY is_default DESC, name ASC
    `).all(parseInt(agent_id, 10));

    res.json(rows);
  } catch (err) {
    console.error('[Email] Error listing signatures:', err);
    res.status(500).json({ error: err.message });
  }
});

// POST /api/email/signatures — create a new signature
router.post('/signatures', (req, res) => {
  try {
    const { agent_id, name, body_html, is_default = 0 } = req.body;
    if (!agent_id || !name) return res.status(400).json({ error: 'agent_id e name sono obbligatori' });

    // If new signature is default, reset others for this agent
    if (is_default) {
      db.prepare(`UPDATE email_signatures SET is_default = 0 WHERE agent_id = ?`).run(parseInt(agent_id, 10));
    }

    const result = db.prepare(`
      INSERT INTO email_signatures (agent_id, name, body_html, is_default)
      VALUES (?, ?, ?, ?)
    `).run(parseInt(agent_id, 10), name, body_html || '', is_default ? 1 : 0);

    res.json({ id: result.lastInsertRowid, agent_id, name, body_html, is_default });
  } catch (err) {
    console.error('[Email] Error creating signature:', err);
    res.status(500).json({ error: err.message });
  }
});

// PUT /api/email/signatures/:id — update a signature
router.put('/signatures/:id', (req, res) => {
  try {
    const { id } = req.params;
    const { agent_id, name, body_html, is_default } = req.body;

    // If new signature is default, reset others for this agent
    if (is_default && agent_id) {
      db.prepare(`UPDATE email_signatures SET is_default = 0 WHERE agent_id = ?`).run(parseInt(agent_id, 10));
    }

    db.prepare(`
      UPDATE email_signatures
      SET name = ?, body_html = ?, is_default = ?, updated_at = strftime('%Y-%m-%dT%H:%M:%fZ', 'now')
      WHERE id = ?
    `).run(name, body_html || '', is_default ? 1 : 0, parseInt(id, 10));

    const updated = db.prepare(`SELECT * FROM email_signatures WHERE id = ?`).get(parseInt(id, 10));
    res.json(updated);
  } catch (err) {
    console.error('[Email] Error updating signature:', err);
    res.status(500).json({ error: err.message });
  }
});

// PATCH /api/email/signatures/:id/default — set a signature as default
router.patch('/signatures/:id/default', (req, res) => {
  try {
    const { id } = req.params;
    const { agent_id } = req.body;

    if (agent_id) {
      db.prepare(`UPDATE email_signatures SET is_default = 0 WHERE agent_id = ?`).run(parseInt(agent_id, 10));
    }

    db.prepare(`
      UPDATE email_signatures SET is_default = 1, updated_at = strftime('%Y-%m-%dT%H:%M:%fZ', 'now')
      WHERE id = ?
    `).run(parseInt(id, 10));

    res.json({ success: true });
  } catch (err) {
    console.error('[Email] Error setting default signature:', err);
    res.status(500).json({ error: err.message });
  }
});

// DELETE /api/email/signatures/:id — delete a signature
router.delete('/signatures/:id', (req, res) => {
  try {
    const { id } = req.params;
    db.prepare(`DELETE FROM email_signatures WHERE id = ?`).run(parseInt(id, 10));
    res.json({ success: true });
  } catch (err) {
    console.error('[Email] Error deleting signature:', err);
    res.status(500).json({ error: err.message });
  }
});

// ─── SEND EMAIL ───────────────────────────────────────────────────────────────

// POST /api/email/send — send an email for a ticket
router.post('/send', async (req, res) => {
    const {
      ticketId,
      to,
      cc = [],
      subject: customSubject,
      bodyHtml,
      attachments = [],
      inlineImages = [],
      agentId,
      agentName = 'Agente',
      keepHelpdeskCopy = true,
    } = req.body;

    if (!ticketId) return res.status(400).json({ error: 'ticketId è obbligatorio' });
    if (!to || !to.length) return res.status(400).json({ error: 'Il campo "to" è obbligatorio' });
    if (!bodyHtml) return res.status(400).json({ error: 'Il corpo della email è obbligatorio' });

    try {
      // 1. Fetch ticket number and title for subject
      const ticketResult = await pool.query(
        `SELECT tn, title FROM ticket WHERE id = $1`,
        [ticketId]
      );
      if (!ticketResult.rows.length) return res.status(404).json({ error: 'Ticket non trovato' });

      const { tn, title } = ticketResult.rows[0];
      const subject = customSubject || `Re: [Ticket#${tn}] ${title}`;

      // 2. Build BCC list (include OTRS system mailbox if keepHelpdeskCopy is true)
      const bcc = [];
      if (keepHelpdeskCopy) {
        const otrsBcc = process.env.OTRS_MAIL_BCC;
        if (otrsBcc) bcc.push(otrsBcc);
      }

    // 3. Send via configured mailer (Graph API or SMTP)
    await sendMail({ to, cc, bcc, subject, bodyHtml, attachments, inlineImages });

    // 4. Log internal note in OTRS ticket via DB (email sent record)
    try {
      const now = Math.floor(Date.now() / 1000);
      const agentLoginResult = agentId
        ? await pool.query(`SELECT login, first_name, last_name FROM users WHERE id = $1`, [agentId])
        : { rows: [] };

      const agentUser = agentLoginResult.rows[0];
      let agentEmail = 'agent@localhost';
      if (agentId) {
        const prefRes = await pool.query(
          `SELECT preferences_value FROM user_preferences WHERE user_id = $1 AND preferences_key = 'UserEmail'`,
          [agentId]
        );
        if (prefRes.rows.length > 0 && prefRes.rows[0].preferences_value) {
          agentEmail = prefRes.rows[0].preferences_value;
        }
      }

      const aFrom = agentUser
        ? `"${agentUser.first_name} ${agentUser.last_name}" <${agentEmail}>`
        : agentName;

      const toList = to.join(', ');
      const noteBody = `Email inviata a: ${toList}${cc.length ? `\nCC: ${cc.join(', ')}` : ''}`;

      // Insert article via DB (internal note to log email dispatch)
      const artInsert = await pool.query(`
        INSERT INTO article (
          ticket_id, article_sender_type_id, communication_channel_id,
          is_visible_for_customer, a_from, a_to, a_subject, a_body,
          content_path, incoming_time, create_time, create_by, change_time, change_by
        ) VALUES (
          $1, 1, 2, 0, $2, $3, $4, $5,
          '/', $6, NOW(), $7, NOW(), $7
        ) RETURNING id`,
        [ticketId, aFrom, toList, `[Email inviata] ${subject}`, noteBody, now, agentId || 1]
      );

      const articleId = artInsert.rows[0]?.id;

      if (articleId) {
        await pool.query(`
          INSERT INTO article_data_mime (article_id, a_from, a_to, a_cc, a_subject, a_body, a_content_type, incoming_time, create_time, create_by, change_time, change_by)
          VALUES ($1, $2, $3, $4, $5, $6, 'text/plain; charset=utf-8', $7, NOW(), $8, NOW(), $8)`,
          [articleId, aFrom, toList, cc.join(', '), subject, noteBody, now, agentId || 1]
        );
      }
    } catch (noteErr) {
      console.warn('[Email] Nota interna OTRS non inserita (non bloccante):', noteErr.message);
    }

    console.log(`[Email] ✅ Email inviata per ticket #${tn} a: ${to.join(', ')}`);
    res.json({ success: true, subject, to });

  } catch (err) {
    console.error('[Email] ❌ Errore invio email:', err.message);
    res.status(500).json({ error: err.message });
  }
});

module.exports = router;