// app.js — the client half of notevi web. Everything here works in the static
// export too; htmx only takes over the parts that need a server (filters,
// comments, live activity, jj queries).
"use strict";

const root = document.documentElement;
const live = root.dataset.live === "1";

// ── focus: trace or notes, never both ─────────────────────────────────────
// Coverage and notes want the same pixels (line background, gutter color,
// tree markers), so the whole UI switches between them instead of layering.
function setMode(m) {
  root.dataset.mode = m;
  localStorage.setItem("notevi-mode", m);
  for (const b of document.querySelectorAll(".mode"))
    b.setAttribute("aria-pressed", String(b.dataset.mode === m));
}
for (const b of document.querySelectorAll(".mode"))
  b.addEventListener("click", () => setMode(b.dataset.mode));
setMode(root.dataset.mode || "trace");

const typing = e =>
  /^(INPUT|TEXTAREA|SELECT)$/.test(e.target.tagName) || e.target.isContentEditable;

// The project hub is fully server-derived; filtering is deliberately local so
// choosing a project does not create another piece of server state.
const projectFind = document.getElementById("projectfind");
if (projectFind) {
  const apply = () => {
    const q = projectFind.value.trim().toLowerCase();
    for (const card of document.querySelectorAll(".project-card"))
      card.hidden = !!q && !(card.dataset.project || "").toLowerCase().includes(q);
  };
  projectFind.addEventListener("input", apply);
  projectFind.addEventListener("search", apply);
  projectFind.addEventListener("keydown", e => {
    if (e.key === "Escape") { projectFind.value = ""; apply(); projectFind.blur(); }
    if (e.key === "Enter") {
      const first = document.querySelector(".project-card:not([hidden]) a.project-action");
      if (first) first.click();
    }
  });
}

document.addEventListener("keydown", e => {
  if (e.metaKey || e.ctrlKey || e.altKey || typing(e)) return;
  if (e.key === "t") setMode(root.dataset.mode === "notes" ? "trace" : "notes");
  if (e.key === "/") {
    const f = document.getElementById("filefind");
    if (f) { e.preventDefault(); f.focus(); f.select(); }
  }
});

// ── theme ─────────────────────────────────────────────────────────────────
// Every theme this machine has is a :root block in themes.css, so wearing one
// is a single attribute — and the menu can therefore preview as it moves.
// Arrow through it or hover and the page changes under you; enter keeps what
// you are wearing, escape puts back the one you came with.
//
// themes.css and themes.js are fetched the first time the menu opens (the
// stylesheet earlier than that, from the head, when a theme is already
// chosen), so a reader who never switches pays nothing for them.
const pick = document.getElementById("themepick");
if (pick) {
  const btn = document.getElementById("themebtn"),
        menu = document.getElementById("thememenu"),
        find = document.getElementById("themefind"),
        list = document.getElementById("themelist");
  const builtin = [
    {id: "system", name: "system", src: "follows the browser"},
    {id: "dark", name: pick.dataset.dark, src: "built with · dark"},
    {id: "light", name: pick.dataset.light, src: "built with · light"},
  ];
  let cur = localStorage.getItem("notevi-theme") || "system";
  let active = null, filled = false, pending = null;

  const wear = id => {
    if (id === "system") delete root.dataset.theme;
    else root.dataset.theme = id;
  };
  // the name of a theme we may not have the menu for yet: kept beside the id
  // so the button says something true before themes.js has loaded
  const label = id => {
    const b = builtin.find(t => t.id === id);
    if (b) return b.name;
    const t = (window.VRSITE_THEMES || []).find(t => t.id === id);
    return t ? t.name : localStorage.getItem("notevi-theme-name") ||
      id.replace(/^[^/]*\//, "").replace(/[-_]/g, " ");
  };
  btn.textContent = label(cur);

  // themes.css is a link and themes.js a script, not a fetch: the static
  // export is opened from the filesystem, where fetch() is not allowed
  const ensure = () => {
    if (!document.getElementById("themescss")) {
      const l = document.createElement("link");
      l.rel = "stylesheet"; l.id = "themescss"; l.href = pick.dataset.css;
      document.head.append(l);
    }
    if (window.VRSITE_THEMES) return Promise.resolve();
    if (!pending) pending = new Promise(done => {
      const s = document.createElement("script");
      s.src = pick.dataset.js;
      s.onload = s.onerror = done;
      document.head.append(s);
    });
    return pending;
  };

  const row = t => {
    const li = document.createElement("li");
    li.setAttribute("role", "option");
    li.id = "themeopt-" + list.children.length;
    li.dataset.id = t.id;
    li.dataset.q = (t.name + " " + t.src + " " + t.id).toLowerCase();
    const sw = document.createElement("span");
    sw.className = t.sw ? "sw" : "sw none"; // empty, but the names still line up
    for (const c of t.sw || []) {
      const chip = document.createElement("i");
      chip.style.background = c;
      sw.append(chip);
    }
    li.append(sw);
    const nm = document.createElement("span");
    nm.className = "nm";
    nm.textContent = t.name;
    const src = document.createElement("span");
    src.className = "src";
    src.textContent = t.src;
    li.append(nm, src);
    return li;
  };

  const fill = () => {
    if (filled) return;
    filled = true;
    // the two the site was built with are usually in the menu as well, so the
    // rows for them can wear the same swatch — and "system", both at once
    const all = window.VRSITE_THEMES || [];
    const swOf = id => (all.find(t => t.id === id) || {}).sw;
    const dsw = swOf(pick.dataset.darkid), lsw = swOf(pick.dataset.lightid);
    builtin[0].sw = dsw && lsw && [...dsw.slice(0, 3), ...lsw.slice(0, 3)];
    builtin[1].sw = dsw;
    builtin[2].sw = lsw;
    for (const t of builtin) list.append(row(t));
    for (const t of window.VRSITE_THEMES || [])
      list.append(row({...t, src: t.src + (t.dark ? " · dark" : " · light")}));
    if (list.children.length === builtin.length) {
      const p = document.createElement("li");
      p.className = "meta";
      p.textContent = "no zed or helix themes found on this machine";
      list.append(p);
    }
  };

  const setActive = (li, preview = true) => {
    if (!li || li === active) return;
    if (active) {
      active.classList.remove("on");
      active.removeAttribute("aria-selected");
    }
    active = li;
    li.classList.add("on");
    li.setAttribute("aria-selected", "true");
    find.setAttribute("aria-activedescendant", li.id);
    li.scrollIntoView({block: "nearest"});
    if (preview) wear(li.dataset.id);
  };

  const rows = () => [...list.querySelectorAll("li[data-id]:not([hidden])")];
  const rowFor = id => list.querySelector('li[data-id="' + CSS.escape(id) + '"]');

  const filter = () => {
    const q = find.value.trim().toLowerCase();
    for (const li of list.children)
      li.hidden = !!q && !(li.dataset.q || "").includes(q);
    if (!active || active.hidden) setActive(rows()[0]);
  };
  find.addEventListener("input", filter);

  const open = () => {
    if (!menu.hidden) return;
    menu.hidden = false;
    btn.setAttribute("aria-expanded", "true");
    find.value = "";
    find.focus();
    ensure().then(() => {
      fill();
      filter();
      for (const li of list.querySelectorAll("li.cur")) li.classList.remove("cur");
      const here = rowFor(cur);
      if (here) here.classList.add("cur");
      setActive(here || rows()[0], false);
    });
  };

  // leaving the menu either keeps what is on screen or puts back what was
  // there before it opened — nothing is stored until it is kept
  const close = keep => {
    if (menu.hidden) return;
    if (keep && active) {
      cur = active.dataset.id;
      localStorage.setItem("notevi-theme", cur);
      localStorage.setItem("notevi-theme-name", label(cur));
      btn.textContent = label(cur);
      for (const li of list.querySelectorAll("li.cur")) li.classList.remove("cur");
      active.classList.add("cur");
    }
    wear(cur);
    menu.hidden = true;
    btn.setAttribute("aria-expanded", "false");
  };

  btn.addEventListener("click", () => (menu.hidden ? open() : close(false)));
  // mousemove, not mouseover: arrowing scrolls rows under a still pointer,
  // and the pointer must not then take the selection back
  list.addEventListener("mousemove", e => {
    const li = e.target.closest("li[data-id]");
    if (li) setActive(li);
  });
  list.addEventListener("click", e => {
    const li = e.target.closest("li[data-id]");
    if (li) { setActive(li); close(true); }
  });
  find.addEventListener("keydown", e => {
    if (e.key === "ArrowDown" || e.key === "ArrowUp") {
      e.preventDefault();
      const all = rows();
      if (!all.length) return;
      const i = all.indexOf(active), step = e.key === "ArrowDown" ? 1 : -1;
      setActive(all[(i + step + all.length) % all.length]);
    } else if (e.key === "Enter") {
      e.preventDefault();
      close(true);
      btn.focus();
    } else if (e.key === "Escape") {
      e.preventDefault();
      close(false);
      btn.focus();
    }
  });
  document.addEventListener("click", e => {
    if (!menu.hidden && !pick.contains(e.target)) close(false);
  });
  document.addEventListener("keydown", e => {
    if (e.key === "Escape") close(false);
    if (e.key === "T" && !e.metaKey && !e.ctrlKey && !e.altKey && !typing(e)) {
      e.preventDefault(); // or the T lands in the filter we just focused
      open();
    }
  });
}

// ── nav tree ──────────────────────────────────────────────────────────────
const nav = document.getElementById("nav");
const tree = document.getElementById("tree");
const state = JSON.parse(localStorage.getItem("notevi-tree") || "{}");

// The file tree can get out of the way without losing repository context or
// the navigation footer. Keep the choice across page loads in this browser.
const fileList = document.getElementById("filelist");
const fileToggle = document.getElementById("filetoggle");
if (fileList && fileToggle) {
  const setFilesHidden = hidden => {
    root.dataset.files = hidden ? "hidden" : "shown";
    fileToggle.setAttribute("aria-expanded", String(!hidden));
    fileToggle.textContent = hidden ? "show files" : "hide files";
    localStorage.setItem("notevi-files-hidden", hidden ? "1" : "0");
  };
  setFilesHidden(localStorage.getItem("notevi-files-hidden") === "1");
  fileToggle.addEventListener("click", () => setFilesHidden(root.dataset.files !== "hidden"));
}

if (nav && tree) {
  const base = nav.dataset.root, cur = nav.dataset.current;
  fetch(nav.dataset.tree).then(r => r.text()).then(t => {
    tree.innerHTML = t.replaceAll('href="@@', 'href="' + base);
    for (const d of tree.querySelectorAll("details"))
      if (d.dataset.path in state) d.open = !!state[d.dataset.path];
    if (cur)
      for (const a of tree.querySelectorAll("a.file"))
        if (a.dataset.path === cur) {
          a.setAttribute("aria-current", "page");
          for (let e = a.parentElement; e && e !== tree; e = e.parentElement)
            if (e.tagName === "DETAILS") e.open = true;
          a.scrollIntoView({block: "center"});
          break;
        }
    tree.addEventListener("toggle", e => {
      if (tree.classList.contains("filtering")) return; // filter drives open state
      state[e.target.dataset.path] = e.target.open ? 1 : 0;
      localStorage.setItem("notevi-tree", JSON.stringify(state));
    }, true);
  }).catch(() => {
    tree.innerHTML = '<p class="meta">tree needs http — use the <a href="' +
      base + 'files.html">file index</a></p>';
  });
}

// ── find a file ───────────────────────────────────────────────────────────
const find = document.getElementById("filefind");
if (find && tree) {
  const apply = () => {
    const q = find.value.trim().toLowerCase();
    tree.classList.toggle("filtering", q !== "");
    for (const a of tree.querySelectorAll("a.file")) {
      const hit = !q || a.dataset.path.toLowerCase().includes(q);
      a.closest("li").hidden = !hit;
      a.classList.toggle("hit", !!q && hit);
    }
    for (const d of tree.querySelectorAll("details")) {
      const any = d.querySelector("li:not([hidden])");
      d.hidden = !!q && !any;
      d.open = q ? !!any : !!state[d.dataset.path];
    }
  };
  find.addEventListener("input", apply);
  find.addEventListener("search", apply);
  find.addEventListener("keydown", e => {
    if (e.key === "Escape") { find.value = ""; apply(); find.blur(); }
    if (e.key === "Enter") {
      const first = tree.querySelector("li:not([hidden]) a.file");
      if (first) first.click();
    }
  });
}

// ── code lines: jump to a note, pick a range to comment on ────────────────
const codeLines = document.querySelectorAll("ol.code li");
const nstart = document.getElementById("nstart"), nend = document.getElementById("nend");
let anchor = 0;

function lineNo(li) { return parseInt(li.id.slice(1), 10) || 0; }

function markSelection(a, b) {
  const lo = Math.min(a, b), hi = Math.max(a, b);
  for (const li of codeLines) {
    const n = lineNo(li);
    li.classList.toggle("sel", n >= lo && n <= hi);
  }
  if (nstart) nstart.value = lo;
  if (nend) nend.value = hi > lo ? hi : "";
}

for (const li of codeLines) {
  li.addEventListener("click", e => {
    const note = li.dataset.note && document.getElementById(li.dataset.note);
    if (note && root.dataset.mode === "notes") {
      note.scrollIntoView({behavior: "smooth", block: "center"});
      note.classList.remove("flash"); void note.offsetWidth; note.classList.add("flash");
    }
    if (!live || root.dataset.mode !== "notes") return;
    const n = lineNo(li);
    if (e.shiftKey && anchor) markSelection(anchor, n);
    else { anchor = n; markSelection(n, n); }
  });
}

// ⌘/ctrl+enter posts the note form from inside the textarea
for (const ta of document.querySelectorAll(".notform textarea"))
  ta.addEventListener("keydown", e => {
    if (e.key === "Enter" && (e.metaKey || e.ctrlKey)) ta.form.requestSubmit();
  });

// ── conversation ──────────────────────────────────────────────────────────
// A session page opened from a note lands on that note, flashed the same way
// clicking a noted line flashes it.
const conv = document.querySelector(".conv[data-anchor]");
if (conv && conv.dataset.anchor) {
  const here = document.getElementById(conv.dataset.anchor);
  if (here) {
    here.scrollIntoView({block: "start"});
    here.classList.remove("flash"); void here.offsetWidth; here.classList.add("flash");
  }
}

// The trip back: a note in a conversation opens the code it was written
// about. The card is the target, so aim anywhere on it — except at the links
// it already carries.
const goTo = w => { location.href = w.dataset.href; };
for (const w of document.querySelectorAll(".notewrap[data-href]")) {
  w.addEventListener("click", e => { if (!e.target.closest("a")) goTo(w); });
  w.addEventListener("keydown", e => {
    if (e.key === "Enter" || e.key === " ") { e.preventDefault(); goTo(w); }
  });
}

// ── arriving at a note ────────────────────────────────────────────────────
// ?note=N means someone followed a note here rather than opening the file:
// show what they came for — notes focus (coverage hides the note), the card
// flashed in the pane, the lines it covers marked.
// A permalink is the same arrival with nothing to scroll to: the page is the
// note, so it only needs the focus that shows notes at all.
if (document.body.dataset.kind === "note") setMode("notes");

const want = new URLSearchParams(location.search).get("note");
if (want && document.body.dataset.kind === "file" && /^\d+$/.test(want)) {
  setMode("notes");
  const card = document.getElementById("note-" + want);
  if (card) {
    // the card's own range, not the lines' data-note: a line belongs to the
    // first note that claimed it, so overlapping notes would mark nothing
    const from = +card.dataset.start, to = +card.dataset.end || +card.dataset.start;
    let first = null;
    for (let n = from; n > 0 && n <= to; n++) {
      const li = document.getElementById("L" + n);
      if (!li) continue;
      li.classList.add("focus");
      first = first || li;
    }
    // after the browser has had its own go at the #L anchor
    if (first) requestAnimationFrame(() => first.scrollIntoView({block: "center"}));
    card.scrollIntoView({block: "nearest"});
    card.classList.remove("flash"); void card.offsetWidth; card.classList.add("flash");
  }
}

// ── note filters ──────────────────────────────────────────────────────────
// Live pages let the server filter (htmx); the static export filters the
// rendered list in place, so the same form works either way.
const filters = document.getElementById("notefilters");
if (filters) {
  const count = document.getElementById("notecount");
  const val = n => (filters.elements[n] ? filters.elements[n].value.trim().toLowerCase() : "");
  const applyLocal = () => {
    const text = val("text"), file = val("file"), agent = val("agent"),
          model = val("model"), session = val("session"), kind = val("kind"),
          from = val("from"), to = val("to");
    let shown = 0;
    for (const art of document.querySelectorAll("#notelist .note")) {
      // the whole rendered body, not its first <p>: a note is markdown, so it
      // may open with a list or a code fence and run to several blocks
      const d = art.dataset, el = art.querySelector(".body");
      const body = (el ? el.textContent : "").toLowerCase();
      const ok =
        (!text || body.includes(text)) &&
        (!file || (d.file || "").toLowerCase().includes(file)) &&
        (!agent || d.agent === filters.elements.agent.value) &&
        (!model || d.model === filters.elements.model.value) &&
        (!session || d.session === filters.elements.session.value) &&
        (!kind || d.kind === filters.elements.kind.value) &&
        (!from || (d.date && d.date >= from)) &&
        (!to || (d.date && d.date <= to));
      art.hidden = !ok;
      if (ok) shown++;
    }
    if (count) count.textContent = shown;
  };
  if (!live) {
    filters.addEventListener("input", applyLocal);
    filters.addEventListener("change", applyLocal);
    filters.addEventListener("submit", e => { e.preventDefault(); applyLocal(); });
  }
  const clear = document.getElementById("clearfilters");
  if (clear) clear.addEventListener("click", () => {
    filters.reset();
    for (const el of filters.elements) if (el.name) el.value = "";
    if (live) window.htmx && htmx.trigger(filters, "change");
    else applyLocal();
  });
}