"use server";

import { revalidatePath } from "next/cache";
import { redirect } from "next/navigation";
import { requireStaff } from "@/lib/admin/guard";
import { prisma } from "@/lib/prisma";
import { siteSettings } from "@/lib/services/site-settings";
import { logStaffActivity } from "@/lib/services/staff-activity";
import { FONTS, PRESETS, THEME_COLOR_KEYS } from "@/lib/theme-presets";
import { presetSettings, settingKey } from "@/lib/theme-settings";

// Only hex/keyword colour values are accepted (matches ThemeVars' sanitiser).
const COLOR_RE = /^[#a-zA-Z0-9(),.\s%-]+$/;
// Extra colour settings beyond the preset palette (buttons + links + gradients).
const HEADING_KEYS = ["size_heading_h1", "size_heading_h2", "size_heading_h3"];
const CUSTOM_CSS_MAX = 20000;

async function writeSetting(key: string, value: string): Promise<void> {
  await prisma.websiteSetting.upsert({
    where: { key },
    update: { value },
    create: { key, value, comment: "Theme (housekeeping)" },
  });
}

export async function saveTheme(formData: FormData): Promise<void> {
  const staff = await requireStaff();

  try {
    for (const mode of ["light", "dark"] as const) {
      for (const key of THEME_COLOR_KEYS) {
        const dbKey = settingKey(key, mode);
        const raw = String(formData.get(dbKey) ?? "").normalize("NFC").trim();
        if (raw && COLOR_RE.test(raw)) await writeSetting(dbKey, raw);
      }
    }
    const radius = String(formData.get("border_radius") ?? "").normalize("NFC").trim();
    if (/^\d{1,3}$/.test(radius)) await writeSetting("border_radius", radius);

    // Typography
    const font = String(formData.get("font_family") ?? "").normalize("NFC").trim();
    if (font in FONTS) await writeSetting("font_family", font);
    for (const key of HEADING_KEYS) {
      const v = String(formData.get(key) ?? "").normalize("NFC").trim();
      if (/^\d{1,3}$/.test(v)) await writeSetting(key, v);
    }

    // Raw custom CSS (staff-trusted; length-capped, ThemeVars injects it as-is).
    if (formData.has("custom_css")) {
      const cssRaw = String(formData.get("custom_css") ?? "").normalize("NFC").slice(0, CUSTOM_CSS_MAX);
      await writeSetting("custom_css", cssRaw);
    }

    siteSettings.reload();
    await logStaffActivity({
      staffId: staff.id,
      action: "theme_update",
      description: "Updated theme settings",
    });
    revalidatePath("/", "layout");
  } catch {
    // ignore — page re-renders current state
  }
  redirect("/admin/theme?saved=1");
}

export async function applyPreset(formData: FormData): Promise<void> {
  const staff = await requireStaff();
  const name = String(formData.get("preset") ?? "").normalize("NFC");
  // eslint-disable-next-line security/detect-object-injection -- guarded by null check below
  const preset = PRESETS[name];
  if (!preset) redirect("/admin/theme");

  try {
    for (const [key, value] of presetSettings(preset)) await writeSetting(key, value);
    await writeSetting("theme_preset", name);
    siteSettings.reload();
    await logStaffActivity({
      staffId: staff.id,
      action: "theme_preset",
      description: `Applied theme preset "${name}"`,
    });
    revalidatePath("/", "layout");
  } catch {
    // ignore
  }
  redirect(`/admin/theme?preset=${encodeURIComponent(name)}`);
}