import { useEffect, useState } from "react";
import type { ActionFunctionArgs, HeadersFunction, LoaderFunctionArgs } from "react-router";
import { useActionData, useLoaderData, useNavigation, useSubmit } from "react-router";
import { useAppBridge } from "@shopify/app-bridge-react";
import { boundary } from "@shopify/shopify-app-react-router/server";
import { authenticate } from "../shopify.server";
import db from "../db.server";
import { ensureShop } from "../lib/shop.server";
import { updateCombinations } from "../lib/publish.server";
import { CONFIG_MAX_BYTES, settingsOf, type ShopSettings } from "../lib/compile";

type Settings = ReturnType<typeof settingsOf> & { menuLinked?: boolean };

export const loader = async ({ request }: LoaderFunctionArgs) => {
  const { admin, session } = await authenticate.admin(request);
  const shop = await ensureShop(admin, session.shop);
  const raw = (shop.settings || {}) as ShopSettings & { menuLinked?: boolean };
  return {
    settings: { ...settingsOf(raw), menuLinked: !!raw.menuLinked } as Settings,
    configBytes: shop.configBytes,
    storefrontBytes: shop.storefrontBytes,
    max: CONFIG_MAX_BYTES,
  };
};

export const action = async ({ request }: ActionFunctionArgs) => {
  const { admin, session } = await authenticate.admin(request);
  const shop = await ensureShop(admin, session.shop);
  const s = JSON.parse(String((await request.formData()).get("payload"))) as Settings;
  const clean: Settings = {
    excludeTag: (s.excludeTag || "").trim().slice(0, 40),
    excludeSubscriptions: !!s.excludeSubscriptions,
    excludeGiftCards: !!s.excludeGiftCards,
    bxgyAllocation: s.bxgyAllocation === "get_units_only" ? "get_units_only" : "all_units",
    combineProduct: !!s.combineProduct,
    combineOrder: !!s.combineOrder,
    combineShipping: !!s.combineShipping,
    afterAdd: s.afterAdd === "drawer" ? "drawer" : "cart",
    accent: /^#[0-9a-fA-F]{6}$/.test(s.accent || "") ? s.accent : "",
    radius: Math.min(Math.max(Math.round(Number(s.radius) || 0), 0), 24),
    menuLinked: !!s.menuLinked,
  };
  await db.shop.update({ where: { id: shop.id }, data: { settings: clean } });
  const outcome = await updateCombinations(admin, session.shop);
  return { ok: outcome.ok, error: outcome.error };
};

export default function SettingsPage() {
  const { settings, configBytes, storefrontBytes, max } = useLoaderData<typeof loader>();
  const result = useActionData<typeof action>();
  const [s, setS] = useState<Settings>(settings);
  const submit = useSubmit();
  const nav = useNavigation();
  const shopify = useAppBridge();
  useEffect(() => {
    if (result?.ok) shopify.toast.show("Settings saved");
    if (result?.error) shopify.toast.show(result.error, { isError: true });
  }, [result, shopify]);
  const set = <K extends keyof Settings>(k: K, v: Settings[K]) => setS((x) => ({ ...x, [k]: v }));
  const save = () => {
    const fd = new FormData();
    fd.set("payload", JSON.stringify(s));
    submit(fd, { method: "post" });
  };
  const pct = Math.round((configBytes / max) * 100);

  return (
    <s-page heading="Settings">
      <s-button slot="primary-action" variant="primary" onClick={save} {...(nav.state !== "idle" ? { loading: true } : {})}>Save</s-button>

      <s-section heading="Exclusions">
        <s-stack gap="base">
          <s-text-field label="Exclusion tag" value={s.excludeTag} details="Products with this tag never count towards a bundle (e.g. marketplace sellers' products)." onInput={(e) => set("excludeTag", e.currentTarget.value)} />
          <s-checkbox label="Exclude subscription items (bought with a selling plan)" checked={s.excludeSubscriptions} onChange={(e) => set("excludeSubscriptions", e.currentTarget.checked)} />
          <s-checkbox label="Exclude gift cards" checked={s.excludeGiftCards} onChange={(e) => set("excludeGiftCards", e.currentTarget.checked)} />
        </s-stack>
      </s-section>

      <s-section heading="Combining with other discounts">
        <s-stack gap="base">
          <s-checkbox label="Combine with other product discounts" checked={s.combineProduct} onChange={(e) => set("combineProduct", e.currentTarget.checked)} />
          <s-checkbox label="Combine with order discounts" checked={s.combineOrder} onChange={(e) => set("combineOrder", e.currentTarget.checked)} />
          <s-checkbox label="Combine with shipping discounts" checked={s.combineShipping} onChange={(e) => set("combineShipping", e.currentTarget.checked)} />
        </s-stack>
      </s-section>

      <s-section heading="Buy X get Y">
        <s-choice-list label="How the discount shows on the items" values={[s.bxgyAllocation]} onChange={(e) => set("bxgyAllocation", (e.currentTarget.values[0] as Settings["bxgyAllocation"]) || "all_units")}>
          <s-choice value="all_units">Spread over all items of the deal (same total, matches the original module)</s-choice>
          <s-choice value="get_units_only">Only on the "get" items (the free item shows as free)</s-choice>
        </s-choice-list>
      </s-section>

      <s-section heading="Storefront">
        <s-stack gap="base">
          <s-choice-list label="After “Add bundle to cart”" values={[s.afterAdd]} onChange={(e) => set("afterAdd", (e.currentTarget.values[0] as Settings["afterAdd"]) || "cart")}>
            <s-choice value="cart">Go to the cart page</s-choice>
            <s-choice value="drawer">Open the theme's cart drawer (if the theme has one)</s-choice>
          </s-choice-list>
          <s-text-field label="Accent colour" value={s.accent} placeholder="#b5462e" details="Leave empty to use your theme's colours." onInput={(e) => set("accent", e.currentTarget.value)} />
          <s-number-field label="Card corner radius" value={String(s.radius)} min={0} max={24} step={1} suffix="px" onInput={(e) => set("radius", Number(e.currentTarget.value))} />
          <s-checkbox label="I've added /apps/bundles to my store menu" checked={!!s.menuLinked} onChange={(e) => set("menuLinked", e.currentTarget.checked)} />
        </s-stack>
      </s-section>

      <s-section heading="Discount configuration size">
        <s-stack gap="small-200">
          <s-text>{configBytes.toLocaleString()} of {max.toLocaleString()} bytes ({pct}%)</s-text>
          <div role="meter" aria-valuenow={pct} aria-valuemin={0} aria-valuemax={100} aria-label="Configuration size" style={{ height: 8, borderRadius: 4, background: "#e3e3e3" }}>
            <div style={{ width: `${Math.min(pct, 100)}%`, height: 8, borderRadius: 4, background: pct > 85 ? "#c70a24" : "#29845a" }} />
          </div>
          <s-text color="subdued">All running offers share one Shopify discount so each item counts once. Storefront data: {storefrontBytes.toLocaleString()} bytes.</s-text>
        </s-stack>
      </s-section>
    </s-page>
  );
}

export const headers: HeadersFunction = (headersArgs) => boundary.headers(headersArgs);