'use node';

import { v } from 'convex/values';
import { UseSend } from 'usesend-js';

import { internal } from './_generated/api';
import { internalAction } from './_generated/server';

/**
 * Best-effort email dispatch for a notification. Runs the getForEmail query,
 * sends via UseSend, and marks the notification emailed on success. Missing
 * UseSend env is logged and swallowed — email is never allowed to throw.
 */
export const sendNotificationEmail = internalAction({
  args: { notificationId: v.id('notifications') },
  handler: async (ctx, { notificationId }) => {
    const { to, title, body, link } = await ctx.runQuery(
      internal.notifications.getForEmail,
      { notificationId },
    );

    if (!to) return;

    const apiKey = process.env.USESEND_API_KEY;
    const useSendUrl = process.env.USESEND_URL;
    const from = process.env.USESEND_FROM_EMAIL;
    if (!apiKey || !useSendUrl || !from) {
      console.warn(
        'Skipping notification email: USESEND_API_KEY, USESEND_URL, and USESEND_FROM_EMAIL must be set.',
      );
      return;
    }

    const text = link ? `${body}\n\n${link}` : body;
    const html = `
      <div style="max-width: 600px; margin: 0 auto; font-family: Arial, sans-serif;">
        <h2>${title}</h2>
        <p>${body}</p>
        ${link ? `<p><a href="${link}">${link}</a></p>` : ''}
      </div>
    `;

    const useSend = new UseSend(apiKey, useSendUrl);
    const result = await useSend.emails.send({
      from,
      to: [to],
      subject: title,
      text,
      html,
    });

    if (result.error) {
      console.error('UseSend error: ' + JSON.stringify(result.error));
      return;
    }

    await ctx.runMutation(internal.notifications.markEmailed, {
      notificationId,
    });
  },
});