// List editor: search providers, add entries, rank and edit them.
import { h, icon, api, readBoot, toast, confirmDialog, openDialog, dialogHead, debounce, busy, fmt } from "./common.js";
import { sortable } from "./sortable.js";
import { openListForm } from "./list-form.js";

const boot = readBoot();
const { categories, limits, productions } = boot;
const cat = boot.category;
const pageSize = boot.pageSize;
let list = boot.list;
let items = [];
let page = 1;

const square = cat.aspect === "square";
const $ = (sel) => document.querySelector(sel);
const rankList = $("[data-rank-list]");
const pager = $("[data-pager]");
const results = $("[data-results]");
const searchForm = $("[data-search]");
const searchInput = searchForm.querySelector("input");
const spinner = searchForm.querySelector(".spinner");
if (square) {
  rankList.classList.add("is-square");
  results.classList.add("is-square");
}

// Category-specific extra fields, stored in item.extra.
const EXTRA_FIELDS = {
  movie: [["genres", "Genres"], ["runtime", "Runtime"]],
  tv: [["genres", "Genres"]],
  album: [["type", "Type (EP, Live…)"], ["label", "Label"], ["genres", "Genres"]],
  song: [["album", "Album"], ["length", "Length"]],
  game: [["platforms", "Platforms"], ["genres", "Genres"]],
  theater: [["venue", "Venue / Theatre"], ["cast", "Notable cast"]],
};

// ---------- header ----------

function renderHeader() {
  document.querySelector("[data-bind=title]").textContent = list.title;
  document.querySelector("[data-bind=count]").textContent = fmt.format(list.itemCount);
  document.querySelector("[data-bind=max]").textContent = fmt.format(list.maxItems);
  document.querySelector("[data-bind=hidden]").textContent = list.visible ? "" : " · Hidden";
  document.querySelector("[data-bind=public]").href = `/l/${list.slug}`;
  document.querySelector("[data-bind=meter]").style.width = Math.min(100, (list.itemCount / list.maxItems) * 100) + "%";
  document.querySelector("[data-bind=provider]").textContent = boot.provider ? `via ${boot.provider}` : "";
  document.title = `${list.title} · ${document.title.split(" · ").pop()}`;
}

const isFull = () => list.itemCount >= list.maxItems;

document.querySelector("[data-action=edit-list]").addEventListener("click", () => {
  openListForm({
    categories, limits, list,
    onSaved: (saved) => {
      list = saved;
      renderHeader();
      renderResults(lastResults);
      toast("List saved");
    },
  });
});

// ---------- ranked items ----------

const pages = () => Math.max(1, Math.ceil(list.itemCount / pageSize));

async function load(p = page, flashId) {
  page = Math.min(Math.max(1, p), pages());
  try {
    items = await api("GET", `/api/lists/${list.id}/items?offset=${(page - 1) * pageSize}&limit=${pageSize}`);
  } catch (err) {
    toast(err.message, { error: true });
    return;
  }
  renderItems(flashId);
}

function artBox(src, alt = "") {
  const box = h("span", { class: "result-art" });
  if (src) {
    const img = h("img", { src, alt, loading: "lazy", referrerpolicy: "no-referrer" });
    img.addEventListener("error", () => img.replaceWith(icon(cat.icon)), { once: true });
    box.append(img);
  } else {
    box.append(icon(cat.icon));
  }
  return box;
}

function row(it) {
  const rankInput = h("input", {
    class: "rank-input", type: "number", min: 1, max: list.itemCount, value: it.rank,
    "aria-label": `Rank of ${it.title}`, inputmode: "numeric",
  });
  const commit = () => {
    const n = Number(rankInput.value);
    if (!Number.isInteger(n) || n === it.rank) { rankInput.value = it.rank; return; }
    moveTo(it, Math.min(Math.max(1, n), list.itemCount));
  };
  rankInput.addEventListener("keydown", (e) => { if (e.key === "Enter") { e.preventDefault(); rankInput.blur(); } });
  rankInput.addEventListener("change", commit);

  const sub = [it.subtitle, it.year].filter(Boolean).join(" · ");
  return h("li", { class: "rank-row", "data-id": it.id },
    h("button", { type: "button", class: "drag-handle", "aria-label": `Drag to reorder ${it.title}, or use arrow keys` }, icon("grip")),
    rankInput,
    artBox(it.image ? `/images/${it.image}` : ""),
    h("div", { class: "rank-row-body" },
      h("div", { class: "rank-row-title" }, it.title),
      h("div", { class: "rank-row-sub" },
        it.extra?.production && h("span", { class: "badge" }, it.extra.production),
        sub && h("span", {}, sub),
        it.note && h("span", { title: "Has a note" }, icon("pencil")),
      ),
    ),
    h("div", { class: "rank-row-actions" },
      h("button", { type: "button", class: "icon-btn hide-sm", "aria-label": "Move up", title: "Move up", disabled: it.rank === 1, onclick: () => moveTo(it, it.rank - 1) }, icon("chevron-up")),
      h("button", { type: "button", class: "icon-btn hide-sm", "aria-label": "Move down", title: "Move down", disabled: it.rank === list.itemCount, onclick: () => moveTo(it, it.rank + 1) }, icon("chevron-down")),
      h("button", { type: "button", class: "icon-btn", "aria-label": `Edit ${it.title}`, title: "Edit", onclick: () => openItemForm({ item: it }) }, icon("pencil")),
      h("button", { type: "button", class: "icon-btn icon-btn--danger", "aria-label": `Remove ${it.title}`, title: "Remove", onclick: () => removeItem(it) }, icon("trash")),
    ),
  );
}

function renderItems(flashId) {
  if (!items.length) {
    rankList.replaceChildren(h("li", { class: "rank-empty" },
      h("div", { class: "empty-art", style: { margin: "0 auto 12px" } }, icon(cat.icon)),
      h("p", {}, `No ${cat.label.toLowerCase()} yet. Search on the left to add your first.`)));
  } else {
    rankList.replaceChildren(...items.map(row));
  }
  if (flashId) {
    const el = rankList.querySelector(`[data-id="${flashId}"]`);
    if (el) {
      el.classList.add("is-flash");
      el.scrollIntoView({ block: "nearest", behavior: "smooth" });
    }
  }
  renderPager();
}

function renderPager() {
  const total = pages();
  if (total <= 1) { pager.replaceChildren(); return; }
  const btn = (p, label = String(p), aria) => h("button", {
    type: "button", class: "pager-btn" + (p === page ? " is-current" : ""), "aria-label": aria,
    "aria-current": p === page ? "page" : null, onclick: () => load(p),
  }, label);
  const nums = [];
  let last = 0;
  for (let i = 1; i <= total; i++) {
    if (i === 1 || i === total || Math.abs(i - page) <= 2) {
      if (last && i - last > 1) nums.push(h("span", { class: "pager-gap" }, "…"));
      nums.push(btn(i, `${fmt.format((i - 1) * pageSize + 1)}–${fmt.format(Math.min(i * pageSize, list.itemCount))}`));
      last = i;
    }
  }
  pager.replaceChildren(...nums);
}

async function moveTo(it, rank) {
  try {
    await api("POST", `/api/items/${it.id}/move`, { rank });
  } catch (err) {
    toast(err.message, { error: true });
  }
  const targetPage = Math.ceil(rank / pageSize);
  await load(targetPage, it.id);
}

sortable(rankList, {
  onMove: async (el, from, to) => {
    const id = Number(el.dataset.id);
    const it = items.find((x) => x.id === id);
    const rank = (page - 1) * pageSize + to + 1;
    // Renumber right away so the UI feels instant; the reload confirms.
    [...rankList.children].forEach((li, i) => {
      const input = li.querySelector(".rank-input");
      if (input) input.value = (page - 1) * pageSize + i + 1;
    });
    try {
      await api("POST", `/api/items/${id}/move`, { rank });
    } catch (err) {
      toast(err.message, { error: true });
    }
    await load(page, it?.id);
  },
});

async function removeItem(it) {
  const ok = await confirmDialog({
    title: "Remove from list?",
    message: `“${it.title}” will be removed from #${it.rank}, and everything below moves up one spot.`,
    confirm: "Remove",
    danger: true,
  });
  if (!ok) return;
  try {
    await api("DELETE", `/api/items/${it.id}`);
    list.itemCount--;
    renderHeader();
    toast(`Removed “${it.title}”`);
    await load();
    markResult(it, 0);
  } catch (err) {
    toast(err.message, { error: true });
  }
}

// ---------- search ----------

let lastResults = null;
let searchSeq = 0;

async function search(q) {
  q = q.trim();
  if (!q) { renderResults(null); return; }
  const seq = ++searchSeq;
  spinner.hidden = false;
  try {
    const data = await api("GET", `/api/search?category=${cat.key}&list=${list.id}&q=${encodeURIComponent(q)}`);
    if (seq !== searchSeq) return;
    renderResults(data.results);
  } catch (err) {
    if (seq !== searchSeq) return;
    lastResults = null;
    const needsSetup = err.status === 424;
    results.replaceChildren(h("div", { class: "alert " + (needsSetup ? "alert--warn" : "alert--error") },
      icon(needsSetup ? "key" : "alert"),
      h("div", {}, err.message, needsSetup && h("div", {}, h("a", { href: "/admin/settings#integrations" }, "Open integrations →")))));
  } finally {
    if (seq === searchSeq) spinner.hidden = true;
  }
}

function resultKey(r) { return `${r.provider}:${r.providerId}`; }

function markResult(it, rank) {
  if (!lastResults || !it.provider) return;
  const r = lastResults.find((x) => x.provider === it.provider && x.providerId === it.providerId);
  if (r) { r.existingRank = rank; renderResults(lastResults); }
}

function renderResults(res) {
  lastResults = res;
  if (res == null) { results.replaceChildren(); return; }
  if (!res.length) {
    results.replaceChildren(h("p", { class: "search-msg" }, "No matches. Try another spelling, or add it manually below."));
    return;
  }
  const full = isFull();
  const nodes = res.map((r) => {
    const sub = [r.subtitle, r.year, r.extra?.type].filter(Boolean).join(" · ");
    const action = r.existingRank
      ? h("span", { class: "result-added" }, icon("check"), `#${r.existingRank}`)
      : h("button", {
        type: "button", class: "btn btn--sm btn--primary", disabled: full,
        title: full ? "This list is full" : `Add to #${list.itemCount + 1}`,
        onclick: (e) => addResult(r, e.currentTarget),
      }, icon("plus"), "Add");
    return h("div", { class: "result", "data-key": resultKey(r) },
      artBox(r.imageUrl, ""),
      h("div", { style: { minWidth: 0 } },
        h("div", { class: "result-title" }, r.title),
        sub && h("div", { class: "result-sub" }, sub),
        r.overview && h("div", { class: "result-overview" }, r.overview),
      ),
      action,
    );
  });
  if (full) nodes.unshift(h("p", { class: "alert alert--warn" }, icon("info"), `This list is full (${fmt.format(list.maxItems)}). Raise its size in List settings to add more.`));
  results.replaceChildren(...nodes);
}

async function addResult(r, button) {
  // Theater entries need the owner to say which production they mean.
  if (cat.key === "theater") {
    openItemForm({ result: r });
    return;
  }
  busy(button, true);
  await createItem({ ...fromResult(r), details: true }, () => busy(button, false));
}

function fromResult(r) {
  return {
    title: r.title, subtitle: r.subtitle, year: r.year, externalUrl: r.externalUrl,
    imageUrl: r.imageUrl, provider: r.provider, providerId: r.providerId, extra: { ...(r.extra || {}) },
  };
}

async function createItem(body, done) {
  try {
    let res;
    try {
      res = await api("POST", `/api/lists/${list.id}/items`, body);
    } catch (err) {
      if (err.status !== 409) throw err;
      const again = await confirmDialog({ title: "Already ranked", message: `${err.message} Add it again anyway?`, confirm: "Add again" });
      if (!again) return null;
      res = await api("POST", `/api/lists/${list.id}/items`, { ...body, force: true });
    }
    list.itemCount++;
    renderHeader();
    toast(`Added “${res.item.title}” at #${res.item.rank}`);
    if (res.warning) toast(res.warning, { error: true });
    markResult(res.item, res.item.rank);
    await load(Math.ceil(res.item.rank / pageSize), res.item.id);
    return res.item;
  } catch (err) {
    toast(err.message, { error: true });
    return null;
  } finally {
    done?.();
  }
}

const runSearch = debounce((q) => search(q), 450);
searchInput.addEventListener("input", () => runSearch(searchInput.value));
searchForm.addEventListener("submit", (e) => { e.preventDefault(); search(searchInput.value); });

document.querySelector("[data-action=manual]").addEventListener("click", () => openItemForm({}));

// ---------- item form (add manually / edit / theater add) ----------

function openItemForm({ item, result }) {
  const editing = !!item;
  const src = item || (result ? fromResult(result) : { extra: {} });
  const extra = { ...(src.extra || {}) };
  let clearImage = false;
  let dlg;

  const field = (label, input, hint) => h("label", { class: "field" },
    h("span", { class: "field-label" }, label), input, hint && h("span", { class: "field-hint" }, hint));

  const title = h("input", { required: true, maxlength: 500, value: src.title || "" });
  const subtitle = h("input", { maxlength: 500, value: src.subtitle || "" });
  const year = h("input", { maxlength: 20, value: src.year || "", inputmode: "numeric", style: { maxWidth: "140px" } });
  const note = h("textarea", { rows: 3, maxlength: 10000, value: item?.note || "", placeholder: "Why it's here. Shown to visitors." });
  const link = h("input", { type: "url", maxlength: 2000, value: src.externalUrl || "", placeholder: "https://" });

  // Theater production gets top billing with suggestions.
  let production, productionList;
  if (cat.key === "theater") {
    productionList = h("datalist", { id: "productions" }, productions.map((p) => h("option", { value: p })));
    production = h("input", { list: "productions", maxlength: 200, value: extra.production || "", placeholder: "e.g. Broadway, North American Tour" });
  }
  const extraInputs = (EXTRA_FIELDS[cat.key] || []).map(([key, label]) => {
    const input = h("input", { maxlength: 500, value: extra[key] || "" });
    return { key, label, input };
  });

  // Artwork
  const currentArt = item?.image ? `/images/${item.image}` : (src.imageUrl || "");
  const preview = h("div", {}, artBox(currentArt));
  const imageUrl = h("input", {
    type: "url", placeholder: "Paste an image URL",
    value: editing ? (item.imageSource && item.imageSource !== "upload" ? item.imageSource : "") : (src.imageUrl || ""),
  });
  imageUrl.addEventListener("change", () => {
    clearImage = false;
    preview.replaceChildren(artBox(imageUrl.value.trim()));
  });
  const fileInput = h("input", { type: "file", accept: "image/jpeg,image/png,image/webp,image/gif,image/avif", hidden: true });
  const uploadBtn = h("button", { type: "button", class: "btn btn--sm", onclick: () => fileInput.click() }, icon("upload"), "Upload");
  fileInput.addEventListener("change", async () => {
    const file = fileInput.files[0];
    if (!file) return;
    if (!editing) {
      toast("Save the entry first, then upload art for it.", { error: true });
      return;
    }
    const fd = new FormData();
    fd.append("file", file);
    busy(uploadBtn, true);
    try {
      const res = await api("POST", `/api/items/${item.id}/image`, fd);
      Object.assign(item, res.item);
      imageUrl.value = "";
      clearImage = false;
      preview.replaceChildren(artBox(`/images/${res.item.image}`));
      toast("Artwork updated");
      await load(page);
    } catch (err) {
      toast(err.message, { error: true });
    } finally {
      busy(uploadBtn, false);
      fileInput.value = "";
    }
  });
  const removeArt = h("button", {
    type: "button", class: "btn btn--sm btn--ghost",
    onclick: () => { clearImage = true; imageUrl.value = ""; preview.replaceChildren(artBox("")); },
  }, icon("x"), "Remove");

  const artHint = cat.key === "theater"
    ? "Tip: use a poster from the specific production (a tour's key art, a revival's Playbill…)."
    : "Art is saved to your server, so it keeps working if the source changes.";

  const error = h("p", { class: "alert alert--error", role: "alert", hidden: true });
  const save = h("button", { type: "submit", class: "btn btn--primary" }, editing ? "Save" : `Add at #${list.itemCount + 1}`);
  const heading = editing ? `Edit #${item.rank}` : result ? `Add “${result.title}”` : `Add a ${cat.singular.toLowerCase()}`;

  const form = h("form", { novalidate: true },
    dialogHead(heading, () => dlg),
    h("div", { class: "dialog-body stack" },
      production && field("Production", production, "Which staging this is about. Pick one or type your own."),
      productionList,
      h("div", { class: "art-edit" + (square ? " is-square" : "") },
        preview,
        h("div", { class: "art-edit-actions" },
          h("span", { class: "field-label" }, "Artwork"),
          imageUrl,
          h("div", { class: "row-btns" }, editing && uploadBtn, removeArt, fileInput),
          h("span", { class: "field-hint" }, artHint),
        ),
      ),
      field("Title", title),
      h("div", { class: "row" },
        field(cat.subtitleHint, subtitle),
        field(cat.key === "theater" ? "Year (of this production)" : "Year", year),
      ),
      extraInputs.length > 0 && h("div", { class: "row" }, extraInputs.map((x) => field(x.label, x.input))),
      field("Your note", note),
      field("Link", link, "Where the title links to on your page."),
      error,
    ),
    h("div", { class: "dialog-foot" },
      h("button", { type: "button", class: "btn", onclick: () => dlg.close() }, "Cancel"),
      save,
    ),
  );

  form.addEventListener("submit", async (e) => {
    e.preventDefault();
    error.hidden = true;
    if (!title.value.trim()) {
      error.hidden = false;
      error.textContent = "Give it a title.";
      title.focus();
      return;
    }
    const newExtra = { ...extra };
    if (production) newExtra.production = production.value.trim();
    for (const x of extraInputs) newExtra[x.key] = x.input.value.trim();
    const body = {
      title: title.value, subtitle: subtitle.value, year: year.value, note: note.value,
      externalUrl: link.value.trim(), extra: newExtra,
      imageUrl: clearImage ? "" : imageUrl.value.trim(), clearImage,
    };
    busy(save, true);
    try {
      if (editing) {
        await api("PUT", `/api/items/${item.id}`, body);
        dlg.close();
        toast("Saved");
        await load(page, item.id);
      } else {
        Object.assign(body, {
          provider: result?.provider || "", providerId: result?.providerId || "", details: !!result,
        });
        const created = await createItem(body);
        if (created) dlg.close();
      }
    } catch (err) {
      error.hidden = false;
      error.textContent = err.message;
    } finally {
      busy(save, false);
    }
  });

  dlg = openDialog(form);
  (production || title).focus();
}

renderHeader();
load(1);