"use server";

import { Resend } from "resend";
import { autoReplyEmail, staffNotificationEmail } from "@/lib/emails";
import { CONTACT_CHANNELS } from "@/lib/site";

export type ContactState = {
  status: "idle" | "success" | "error";
  message: string;
  fieldErrors?: Partial<Record<"name" | "email" | "subject" | "message", string>>;
};

const EMAIL_RE = /^[^\s@]+@[^\s@]+\.[^\s@]+$/;

export async function sendContact(
  _prev: ContactState,
  formData: FormData,
): Promise<ContactState> {
  const name = String(formData.get("name") ?? "").trim();
  const email = String(formData.get("email") ?? "").trim();
  const subject = String(formData.get("subject") ?? "").trim();
  const message = String(formData.get("message") ?? "").trim();
  const honeypot = String(formData.get("website") ?? "");

  // Which desk the message is for. Never trusted as-is: it only counts when it
  // matches a declared channel, so a crafted request cannot inject a label
  // into the staff email subject.
  const rawTopic = String(formData.get("topic") ?? "").trim();
  const topic = CONTACT_CHANNELS.some((channel) => channel.label === rawTopic)
    ? rawTopic
    : null;

  if (honeypot) {
    return { status: "success", message: "Thanks for reaching out." };
  }

  const fieldErrors: ContactState["fieldErrors"] = {};
  if (!name) fieldErrors.name = "Required.";
  if (!email || !EMAIL_RE.test(email)) fieldErrors.email = "Valid email required.";
  if (!subject) fieldErrors.subject = "Required.";
  if (!message || message.length < 10) {
    fieldErrors.message = "Tell us a bit more (10+ chars).";
  }

  if (Object.keys(fieldErrors).length > 0) {
    return {
      status: "error",
      message: "Please fix the highlighted fields.",
      fieldErrors,
    };
  }

  const apiKey = process.env.RESEND_API_KEY;
  const to = process.env.CONTACT_TO_EMAIL;
  const from = process.env.CONTACT_FROM_EMAIL;

  if (!apiKey || !to || !from) {
    console.error(
      "[contact] Missing email env vars (RESEND_API_KEY / CONTACT_TO_EMAIL / CONTACT_FROM_EMAIL).",
    );
    return {
      status: "error",
      message: "Email isn't configured yet. Please try again later.",
    };
  }

  // The studio inbox is a single address, so the desk is carried in the
  // subject line — that is what makes it filterable.
  const contact = {
    name,
    email,
    subject: topic ? `[${topic}] ${subject}` : subject,
    message,
  };

  try {
    const resend = new Resend(apiKey);

    // Critical: notify the studio staff. If this fails, surface an error.
    const staff = staffNotificationEmail(contact);
    const { error } = await resend.emails.send({
      from,
      to,
      replyTo: email,
      subject: staff.subject,
      html: staff.html,
      text: staff.text,
    });

    if (error) {
      console.error("[contact] Resend error (staff):", error);
      return {
        status: "error",
        message: "Something went wrong sending your message. Please try again.",
      };
    }

    // Best-effort: send an acknowledgement to the visitor. A failure here
    // shouldn't fail the whole submission — the staff was already notified.
    try {
      const reply = autoReplyEmail(contact);
      const { error: replyError } = await resend.emails.send({
        from,
        to: email,
        subject: reply.subject,
        html: reply.html,
        text: reply.text,
      });
      if (replyError) {
        console.error("[contact] Resend error (auto-reply):", replyError);
      }
    } catch (replyErr) {
      console.error("[contact] Auto-reply failed:", replyErr);
    }
  } catch (err) {
    console.error("[contact] Unexpected error:", err);
    return {
      status: "error",
      message: "Something went wrong sending your message. Please try again.",
    };
  }

  return {
    status: "success",
    message: "Message sent. We'll get back to you soon.",
  };
}