import { readJSON, enhance, icon } from "./ui.js";
import {
  defaults,
  catalogView,
  bindCatalog,
  overviewView,
  detailView,
  bindDetail,
} from "./catalog.js";
import { methodsView, somaView, samplesView } from "./reference.js";
import synthetic from "./synthetic.js?v=history-20261103";

const app = document.getElementById("app");
let context;
let currentRoute;

function route() {
  const [path, search = ""] = (location.hash.slice(1) || "catalog").split("?");
  const [page, part] = path.split("/");
  return { page, part, params: new URLSearchParams(search) };
}

function filtersFrom(params) {
  const filters = { ...defaults };
  for (const key of [
    "q",
    "source",
    "method",
    "tier",
    "status",
    "sort",
    "route",
  ]) {
    if (params.has(key)) filters[key] = params.get(key);
  }
  filters.preview = params.get("preview") === "true";
  if (!["name", "year", "status"].includes(filters.sort)) filters.sort = "name";
  return filters;
}

function render() {
  if (!context) return;
  synthetic.unmount();
  app.querySelectorAll("video").forEach((video) => video.pause());
  const { page, part, params } = route();
  let active = page,
    title,
    html;
  const datasetId = page.startsWith("ds-") ? page.slice(3) : null;
  if (datasetId) {
    const tab = ["overview", "annotation", "access", "conversion"].includes(
      part,
    )
      ? part
      : "overview";
    title = context.byId[datasetId]?.name || "未找到数据集";
    active = "catalog";
    html = detailView(datasetId, tab, context);
  } else if (page === "synthetic") {
    title = "EgoRenderer";
    html = synthetic.render();
  } else if (page === "overview") {
    title = "数据分布";
    html = overviewView(context);
  } else if (page === "methods") {
    title = "标注方法";
    html = methodsView(context);
  } else if (page === "soma") {
    title = "SOMA转换";
    html = somaView(context);
  } else if (page === "samples") {
    title = "样例";
    html = samplesView(context);
  } else {
    title = "数据集";
    active = "catalog";
    html = catalogView(context, filtersFrom(params));
  }
  app.innerHTML = html;
  document.title = `${title} · EgoNet Datasets`;
  document.querySelectorAll("[data-page]").forEach((link) => {
    if (link.dataset.page === active) link.setAttribute("aria-current", "page");
    else link.removeAttribute("aria-current");
  });
  if (active === "catalog" && !datasetId)
    bindCatalog(context, filtersFrom(params));
  if (datasetId) bindDetail(datasetId, context);
  if (page === "synthetic") synthetic.mount();
  enhance();
  document.getElementById("nav-toggle").setAttribute("aria-expanded", "false");
  document.getElementById("site-nav").classList.remove("is-open");
  const heading = app.querySelector("h1");
  if (heading) {
    heading.tabIndex = -1;
    heading.focus({ preventScroll: true });
  }
  const anchor =
    part &&
    (page === "methods"
      ? "method-" + part
      : page === "soma"
        ? "route-" + part
        : null);
  if (anchor && document.getElementById(anchor))
    document.getElementById(anchor).scrollIntoView();
  else if (currentRoute !== location.hash) window.scrollTo(0, 0);
  currentRoute = location.hash;
}

async function boot() {
  app.innerHTML = '<div class="loading-state" role="status">读取数据集…</div>';
  try {
    const [data, previews, figures, videos, sampling] = await Promise.all([
      readJSON("data/datasets.json"),
      ...["previews", "figures", "videos", "sampling"].map((name) =>
        readJSON(`data/${name}.json`, { optional: true }),
      ),
    ]);
    if (
      !Array.isArray(data.datasets) ||
      new Set(data.datasets.map((d) => d.id)).size !== data.datasets.length
    )
      throw new Error("Dataset schema");
    const by = (items) =>
      Object.fromEntries(
        items.map((value, order) => [value.id, { ...value, order }]),
      );
    context = {
      data,
      previews,
      figures,
      videos,
      sampling,
      byId: by(data.datasets),
      meta: {
        source: by(data.meta.sources),
        method: by(data.meta.methods),
        tier: by(data.meta.tiers),
        status: by(data.meta.statuses),
        route: by(data.meta.routes),
      },
    };
    document.getElementById("catalog-count").textContent = data.datasets.length;
    document.getElementById("data-updated").textContent = data.meta.updated;
    render();
  } catch (_) {
    app.innerHTML = `<div class="empty-state" role="alert"><i data-lucide="wifi-off" aria-hidden="true"></i><h1>数据集暂不可用</h1>${icon("refresh-cw", "重新加载", 'id="retry-load"')}</div>`;
    document.getElementById("retry-load").onclick = boot;
    enhance();
  }
}

const themeButton = document.getElementById("theme-toggle");
let savedTheme;
try {
  savedTheme = localStorage.getItem("atlas-theme");
} catch (_) {
  /* Embedded storage may be restricted. */
}
function setTheme(theme) {
  document.documentElement.dataset.theme = theme;
  themeButton.title = `切换${theme === "dark" ? "浅色" : "深色"}模式`;
  themeButton.setAttribute("aria-label", themeButton.title);
  themeButton.innerHTML = `<i data-lucide="${theme === "dark" ? "sun" : "moon"}" aria-hidden="true"></i>`;
  enhance();
}
setTheme(
  savedTheme ||
    (matchMedia("(prefers-color-scheme: dark)").matches ? "dark" : "light"),
);
themeButton.onclick = () => {
  const theme =
    document.documentElement.dataset.theme === "dark" ? "light" : "dark";
  try {
    localStorage.setItem("atlas-theme", theme);
  } catch (_) {
    /* Keep the current theme without persistence. */
  }
  setTheme(theme);
};
document.getElementById("nav-toggle").onclick = (event) => {
  const button = event.currentTarget;
  const open = button.getAttribute("aria-expanded") !== "true";
  button.setAttribute("aria-expanded", String(open));
  document.getElementById("site-nav").classList.toggle("is-open", open);
};
window.addEventListener("hashchange", render);
document.querySelector(".skip-link").onclick = (event) => {
  event.preventDefault();
  app.focus();
  app.scrollIntoView();
};
document.addEventListener("keydown", (event) => {
  if (
    event.key === "Escape" &&
    document.getElementById("site-nav").classList.contains("is-open")
  ) {
    document.getElementById("site-nav").classList.remove("is-open");
    document
      .getElementById("nav-toggle")
      .setAttribute("aria-expanded", "false");
    document.getElementById("nav-toggle").focus();
  }
});
boot();