/* Brain of Reese — RAG view (the knowledge base catalog; phase 76
 * task 02: shell view module — formerly the standalone sources.html).
 *
 * Wires the real `GET /api/docs` endpoint (import phase): stat cards +
 * full-width document table, or the designed empty state when nothing
 * is indexed yet. Cells are built with DOM APIs (textContent) — never
 * innerHTML with document-derived data (XSS-safe by construction).
 *
 * Phase 76 (task 02) — shell view module (the "RAG" view of the
 * ONE-document shell; /sources.html now serves the shell, and
 * assets/router.js lazy-imports THIS module on first show):
 *
 *   • the top-level boot is now `export async function mount(root)` —
 *     root is the view's <section id="view-rag">, and every DOM lookup
 *     scopes to root (the view ids stay unique across the shell —
 *     scoped lookups keep the module honest and testable). The router
 *     mounts a view ONCE (mount-once, hide-forever), so the bindings,
 *     the sync state machine, and the in-flight poll survive every
 *     switch.
 *   • the initSharedHeader() call is DROPPED: in the shell the shared
 *     header boots exactly once, via the chat module (app.js) at shell
 *     boot — the view never re-boots it. The admin gate (sync button
 *     reveal + the anonymous catalog gate) keeps fetchIsAdmin() — the
 *     SAME cached /api/whoami promise header.js exports (zero extra
 *     requests).
 *   • the document modal needs NO wiring change: the shell keeps
 *     EXACTLY ONE #doc-modal-* skeleton (the chat's, body level), and
 *     both app.js (chat chips) and this module (RAG row links) open
 *     documents through the shared openDocumentModal(...) against that
 *     single instance (assets/document-modal.js, resolved by
 *     document-level querySelector at import).
 *
 * The sync button (phase 32) + the live two-job progress contract
 * (phase 64 task 04) and the table rows (phase 26: same-page modal
 * links) are unchanged in content — only the boot shape moved.
 */

import { fetchIsAdmin } from "./header.js";
import { openDocumentModal } from "./document-modal.js"; // phase 26: row links open the same-page modal

/* Viewer link (phase 10) — same encoded URL the chat chips use; both
 * query values are percent-encoded (paths contain slashes, sometimes
 * spaces). Phase 26: this is the href the .doc-link CARRIES (no-JS /
 * context-menu escape hatch) — the left-click opens the same-page modal
 * instead. */
export function documentUrl(source, path) {
  return "/document.html?source=" + encodeURIComponent(source) + "&path=" + encodeURIComponent(path);
}

export async function mount(root) {
  /* ---------- Sync sources button (Sources page only) ----------
   *
   * The §7.4 never-stale lifecycle: idle → click → POST /api/sync
   * → running (2 s poll of GET /api/sync/status) → success | failed.
   * Admin-only: the button SHIPS hidden and the view boot below reveals
   * it for the admin on the SAME cached whoami fetchIsAdmin() reads
   * (no extra fetch); the 403 branches stay as defense in depth. A failed run
   * opens an error modal (same as the former header.js module — recreated
   * here since the navbar button is gone).
   *
   * Phase 64 (task 04): the button reports the FILE being processed, not
   * just "Syncing…" — TWO jobs drive it. Each poll tick fetches BOTH
   * status endpoints — GET /api/sync/status +
   * GET /api/git-sources/upload/status — and applies this decision
   * tree, in order (startSyncPolling):
   *   1. sync running   → "Syncing… <file> (n/m)" — bare "Syncing…" until
   *                       the import's first file (clone/pull, A4);
   *   2. upload running → "Importing <file> (n/m)" — the background
   *                       archive scan (the "clicked upload, then opened
   *                       sources" contract, A3);
   *   3. sync success   → the phase-32 settle (counts + catalog refresh);
   *   4. sync failed    → the phase-32 failure (banner + modal);
   *   5. upload success → settle "Sync sources" + catalog refresh
   *                       (loadDocs — the new documents must appear); the
   *                       upload's counts live on the Sources page, never
   *                       in #sync-result (A3);
   *   6. upload failed  → settle "Sync sources" — the failure is the
   *                       Sources page's error banner, never this page's (A3);
   *   7. both idle      → retry-ready idle.
   * The live label is the status endpoint's full source/relative/path
   * (A4): CSS ellipsizes #sync-label; the full untruncated path also
   * rides the button title (hover) and #sync-result (the aria-live
   * announcer — screen readers hear it). The load-time re-attach
   * (initSyncButton) re-enters a RUNNING upload the same way; a terminal
   * upload is a no-op there (the boot-time loadDocs() already shows the
   * current catalog).
   *
   * Elements: #sync-btn (the button), #sync-label (the text),
   * #sync-icon (the spinner icon), #sync-result (aria-live result
   * line), #sync-error-banner / #sync-error-text (error banner).
   */
  const syncBtn = root.querySelector("#sync-btn");
  const syncLabel = syncBtn ? syncBtn.querySelector(".sync-label") : null;
  const syncIcon = syncBtn ? syncBtn.querySelector(".sync-icon") : null;
  const syncResult = root.querySelector("#sync-result");
  const syncErrorBanner = root.querySelector("#sync-error-banner");
  const syncErrorText = root.querySelector("#sync-error-text");

  const SYNC_POLL_MS = 2000;
  let syncPollTimer = null;
  let lastSyncState = null;

  function emitSyncStatus(status) {
    lastSyncState = status.state;
    window.dispatchEvent(new CustomEvent("bor:sync-status", { detail: status }));
  }

  function stopSyncPolling() {
    if (syncPollTimer !== null) {
      clearTimeout(syncPollTimer);
      syncPollTimer = null;
    }
  }

  function fmtSyncTime(iso) {
    const d = new Date(iso);
    if (Number.isNaN(d.getTime())) return "";
    const pad = (n) => String(n).padStart(2, "0");
    return `${pad(d.getHours())}:${pad(d.getMinutes())}`;
  }

  /* Phase 64 (task 04): the live-file label. `kind` picks the prefix —
   * "sync" → "Syncing…", "upload" → "Importing" (the background scan's
   * word, A3). The current file — the status endpoint's full
   * source/relative/path (A4) — is appended while one is being processed;
   * the BARE prefix shows during the clone/pull (sync) or unpack (upload)
   * phase, before any file is indexed. The counts appear only once the
   * import has started (total > 0). CSS ellipsizes the button label; the
   * same untruncated text goes to the button title + #sync-result (the
   * aria-live announcer). */
  function fmtSyncLabel(kind, currentFile, done, total) {
    const prefix = kind === "upload" ? "Importing" : "Syncing…";
    let label = currentFile ? `${prefix} ${currentFile}` : prefix;
    if (total > 0) label += ` (${done}/${total})`;
    return label;
  }

  function fmtSyncResult(detail) {
    const d = detail || {};
    const added = d.added || 0;
    const updated = d.updated || 0;
    const parts = [`${added} added`];
    if (updated > 0) parts.push(`${updated} updated`);
    if ((d.unchanged || 0) > 0 || (added === 0 && updated === 0)) {
      parts.push(`${d.unchanged || 0} unchanged`);
    }
    if ((d.pruned || 0) > 0) parts.push(`${d.pruned} pruned`);
    return parts.join(" · ");
  }

  function sanitizeSyncError(message) {
    const text = String(message || "The sync failed.").replace(/\s+/g, " ").trim();
    return text.length > 200 ? `${text.slice(0, 200)}…` : text;
  }

  /* The single running-state entry point (phase 64 task 04: the label
   * carries the live file — `kind` "sync" | "upload", the status
   * endpoint's current_file + done/total). Same mechanics as before
   * (disabled, aria-busy, spinning icon, no is-error) plus: the full
   * untruncated path on the button title (removed when null — no file
   * yet) and in #sync-result (the aria-live announcer reads the full
   * live path; CSS ellipsizes the button's label span only). */
  function enterSyncRunningState(kind, currentFile, done, total) {
    if (!syncBtn) return;
    syncBtn.disabled = true;
    syncBtn.setAttribute("aria-busy", "true");
    if (currentFile) syncBtn.title = currentFile;
    else syncBtn.removeAttribute("title");
    syncBtn.setAttribute("aria-label", "Sync sources");
    syncBtn.classList.remove("is-error");
    if (syncIcon) syncIcon.classList.add("is-spinning");
    const label = fmtSyncLabel(kind, currentFile, done, total);
    if (syncLabel) syncLabel.textContent = label;
    if (syncResult) syncResult.textContent = label;
  }

  function settleSyncButton(label) {
    if (!syncBtn) return;
    syncBtn.disabled = false;
    syncBtn.removeAttribute("aria-busy");
    syncBtn.removeAttribute("title");
    syncBtn.setAttribute("aria-label", "Sync sources");
    syncBtn.classList.remove("is-error");
    if (syncIcon) syncIcon.classList.remove("is-spinning");
    if (syncLabel) syncLabel.textContent = label;
  }

  function showSyncError(detail) {
    if (syncErrorText) syncErrorText.textContent = detail || "The sync failed.";
    if (syncErrorBanner) syncErrorBanner.hidden = false;
  }

  function hideSyncError() {
    if (syncErrorText) syncErrorText.textContent = "";
    if (syncErrorBanner) syncErrorBanner.hidden = true;
  }

  /* ---------- sync failure modal (recreated here since the navbar button is gone) ---------- */
  let syncModal = null;
  let syncModalReturnFocus = null;

  function createSyncModal() {
    const backdrop = document.createElement("div");
    backdrop.className = "sync-modal-backdrop";
    backdrop.innerHTML =
      '<div class="sync-modal" role="alertdialog" aria-modal="true" ' +
      'aria-labelledby="sync-modal-title" aria-describedby="sync-modal-error">' +
      '<h2 id="sync-modal-title">Sync failed</h2>' +
      '<p id="sync-modal-error"></p>' +
      '<button type="button" class="sync-modal-close" aria-label="Close error dialog">\u00d7</button>' +
      "</div>";
    document.body.appendChild(backdrop);
    backdrop.querySelector(".sync-modal-close").addEventListener("click", closeSyncModal);
    backdrop.addEventListener("click", (e) => {
      if (e.target === backdrop) closeSyncModal();
    });
    document.addEventListener("keydown", (e) => {
      if (e.key === "Escape" && backdrop.classList.contains("is-open")) closeSyncModal();
    });
    return backdrop;
  }

  function showSyncModal(error) {
    if (!syncBtn || !document.body) return;
    if (!syncModal) syncModal = createSyncModal();
    syncModal.querySelector("#sync-modal-error").textContent = error;
    if (syncModal.classList.contains("is-open")) return;
    const active = document.activeElement;
    syncModalReturnFocus = active && active !== document.body ? active : syncBtn;
    syncModal.classList.add("is-open");
    syncModal.querySelector(".sync-modal-close").focus();
  }

  function closeSyncModal() {
    if (!syncModal || !syncModal.classList.contains("is-open")) return;
    syncModal.classList.remove("is-open");
    const target = syncModalReturnFocus;
    syncModalReturnFocus = null;
    if (target && document.contains(target)) target.focus();
  }

  function applySyncSuccess(status) {
    const time = fmtSyncTime(status.finished_at);
    settleSyncButton(time ? `Synced ${time}` : "Synced");
    if (syncResult) syncResult.textContent = fmtSyncResult(status.detail);
    hideSyncError();
    emitSyncStatus(status);
    // Refresh the catalog live — the KB just changed.
    loadDocs();
  }

  function applySyncFailure(status) {
    const error = sanitizeSyncError(status.error);
    settleSyncButton("Sync sources");
    if (syncBtn) {
      syncBtn.title = error;
      syncBtn.setAttribute("aria-label", error);
      syncBtn.classList.add("is-error");
    }
    if (syncResult) syncResult.textContent = "";
    showSyncError(error);
    emitSyncStatus(status);
    showSyncModal(error);
  }

  function applySyncIdle(status) {
    settleSyncButton("Sync sources");
    emitSyncStatus(status || { state: "idle" });
  }

  /* The 2 s poll (phase 64 task 04): each tick fetches BOTH jobs — the
   * sync AND the background upload scan — and applies the two-job
   * decision tree in order (see the section header). The 403 on the SYNC
   * fetch hides the button (the whoami backstop); a 403 on the UPLOAD
   * fetch is simply "no upload" (never a hide), and a network blip on
   * either fetch retries next tick. */
  function startSyncPolling() {
    if (syncPollTimer !== null) return;
    const tick = async () => {
      let syncStatus = null;
      let uploadStatus = null;
      let notAdmin = false;
      try {
        const r = await fetch("/api/sync/status");
        if (r.status === 403) notAdmin = true;
        else if (r.ok) syncStatus = await r.json();
      } catch { /* network blip — retry next tick */ }
      if (notAdmin) {
        stopSyncPolling();
        if (syncBtn) syncBtn.hidden = true;
        applySyncIdle();
        return;
      }
      // The SECOND job: the background upload scan (admin-only surface).
      try {
        const ur = await fetch("/api/git-sources/upload/status");
        if (ur.ok) uploadStatus = await ur.json();
      } catch { /* network blip — retry next tick */ }
      if (!syncStatus) {
        syncPollTimer = setTimeout(tick, SYNC_POLL_MS);
        return;
      }
      // 1. sync running: the live sync file (bare "Syncing…" until the
      //    import's first file — A4).
      if (syncStatus.state === "running") {
        enterSyncRunningState(
          "sync", syncStatus.current_file, syncStatus.files_done, syncStatus.files_total
        );
        syncPollTimer = setTimeout(tick, SYNC_POLL_MS);
        return;
      }
      // 2. upload running: the same animation, the upload's file (A3).
      if (uploadStatus && uploadStatus.state === "running") {
        enterSyncRunningState(
          "upload", uploadStatus.current_file, uploadStatus.files_done, uploadStatus.files_total
        );
        syncPollTimer = setTimeout(tick, SYNC_POLL_MS);
        return;
      }
      if (syncStatus.state === "success") {
        stopSyncPolling();
        applySyncSuccess(syncStatus);
        return;
      }
      if (syncStatus.state === "failed") {
        stopSyncPolling();
        applySyncFailure(syncStatus);
        return;
      }
      // 5. upload success: settle + catalog refresh (A3 — the upload's
      //    counts live on the Sources page; #sync-result stays empty).
      if (uploadStatus && uploadStatus.state === "success") {
        stopSyncPolling();
        settleSyncButton("Sync sources");
        if (syncResult) syncResult.textContent = "";
        hideSyncError();
        emitSyncStatus({ state: "idle" });
        loadDocs();
        return;
      }
      // 6. upload failed: settle only — the failure is the Sources page's
      //    error banner, never this page's (A3).
      if (uploadStatus && uploadStatus.state === "failed") {
        stopSyncPolling();
        settleSyncButton("Sync sources");
        if (syncResult) syncResult.textContent = "";
        hideSyncError();
        emitSyncStatus({ state: "idle" });
        return;
      }
      // 7. both idle: settle retry-ready.
      stopSyncPolling();
      applySyncIdle(syncStatus);
    };
    syncPollTimer = setTimeout(tick, SYNC_POLL_MS);
  }

  async function startSync() {
    let r;
    try {
      r = await fetch("/api/sync", { method: "POST" });
    } catch {
      applySyncFailure({
        state: "failed",
        error: "Could not reach the server to start the sync — try again.",
      });
      return;
    }
    if (r.status === 403) {
      stopSyncPolling();
      if (syncBtn) syncBtn.hidden = true;
      applySyncIdle();
      return;
    }
    if (r.status === 202 || r.status === 409) {
      // Phase 64: the run is just starting (model check / clone-pull) —
      // bare "Syncing…" until the first polled file (A4); entering the
      // running state also clears #sync-result with the same label.
      enterSyncRunningState("sync", null, 0, 0);
      hideSyncError();
      if (lastSyncState !== "running") emitSyncStatus({ state: "running" });
      startSyncPolling();
      return;
    }
    let detail = "";
    try { detail = (await r.json()).detail || ""; } catch { /* non-JSON */ }
    applySyncFailure({
      state: "failed",
      error: detail || `The server refused to start the sync (${r.status}).`,
    });
  }

  /* Load-time re-attach (ADMIN ONLY): a running run re-enters running
   * state, a terminal run renders its last result. Phase 64 (A3): with
   * the sync IDLE, an in-flight background upload scan adopts the button
   * the same way — the "user clicked upload, then opened sources" case;
   * a terminal upload is a no-op (the boot-time loadDocs() already shows
   * the current catalog). */
  async function initSyncButton() {
    if (!syncBtn) return;
    if (!(await fetchIsAdmin())) return;
    let status;
    try {
      const r = await fetch("/api/sync/status");
      if (r.status === 403) { syncBtn.hidden = true; return; }
      if (!r.ok) return;
      status = await r.json();
    } catch { return; }
    if (status.state === "running") {
      enterSyncRunningState(
        "sync", status.current_file, status.files_done, status.files_total
      );
      emitSyncStatus(status);
      startSyncPolling();
      return;
    }
    if (status.state === "success") {
      applySyncSuccess(status);
      return;
    }
    if (status.state === "failed") {
      applySyncFailure(status);
      return;
    }
    // Sync idle: check the SECOND job — an in-flight upload scan re-attaches.
    let upload;
    try {
      const ur = await fetch("/api/git-sources/upload/status");
      if (ur.ok) upload = await ur.json();
    } catch { /* network blip — the idle settle below is still honest */ }
    if (upload && upload.state === "running") {
      enterSyncRunningState(
        "upload", upload.current_file, upload.files_done, upload.files_total
      );
      emitSyncStatus({ state: "running" });
      startSyncPolling();
      return;
    }
    applySyncIdle(status);
  }

  if (syncBtn) {
    syncBtn.addEventListener("click", startSync);
    initSyncButton();
  }

  const tbody = root.querySelector("#docs-tbody");
  const emptyEl = root.querySelector("#sources-empty");
  const tableWrap = root.querySelector(".table-wrap");
  const statCards = root.querySelector("#stat-cards");
  const gateEl = root.querySelector("#sources-gate");
  const statDocs = root.querySelector("#stat-docs");
  const statChunks = root.querySelector("#stat-chunks");
  const statLast = root.querySelector("#stat-last");

  /* Phase 16: whoami BEFORE the docs fetch. Anonymous visitors get the
   * sign-in gate (stat cards + table hidden) and NO /api/docs call — the
   * catalog is admin-only. The document viewer itself stays public (the
   * soft rule), so the gate copy points at what keeps working.
   * Phase 76 (task 02): the whoami request is the shared header module's
   * cached promise — fetchIsAdmin(), the same single request the shell's
   * header boots (zero extra requests). */
  function fmtDate(iso) {
    try {
      return new Date(iso).toLocaleString();
    } catch {
      return iso;
    }
  }


  async function loadDocs() {
    let r;
    try {
      r = await fetch("/api/docs");
    } catch {
      showEmpty();
      return;
    }
    if (!r.ok) {
      showEmpty();
      return;
    }
    const { documents } = await r.json();
    if (!documents.length) {
      showEmpty();
      return;
    }

    tbody.replaceChildren();
    let totalChunks = 0;
    let last = "";
    for (const d of documents) {
      totalChunks += d.chunks;
      if (d.indexed_at > last) last = d.indexed_at;
      tbody.appendChild(makeRow(d));
    }
    statDocs.textContent = String(documents.length);
    statChunks.textContent = String(totalChunks);
    statLast.textContent = last ? fmtDate(last) : "–";
    emptyEl.hidden = true;
    tableWrap.hidden = false;
  }

  function makeRow(d) {
    const tr = document.createElement("tr");

    const sourceTd = document.createElement("td");
    sourceTd.textContent = d.source; // document-derived text — never innerHTML
    tr.appendChild(sourceTd);

    // Path cell: a link to the document (phase 10), full path as the
    // accessible/hover name (the column is ellipsized). Phase 26: the
    // left-click opens the same-page modal — no new tab (document-modal.js);
    // the href stays as the no-JS / context-menu escape hatch.
    const pathTd = document.createElement("td");
    pathTd.title = d.path; // full path on hover (column is ellipsized)
    const link = document.createElement("a");
    link.className = "doc-link";
    link.href = documentUrl(d.source, d.path);
    link.addEventListener("click", (e) => {
      e.preventDefault(); // no new tab (phase 26) — the modal takes over
      e.stopPropagation();
      openDocumentModal(d.source, d.path, link);
    });
    link.title = d.path; // full path as the link's hover/accessible name
    link.textContent = d.path;
    pathTd.appendChild(link);
    tr.appendChild(pathTd);

    for (const value of [d.title, String(d.chunks), fmtDate(d.indexed_at)]) {
      const td = document.createElement("td");
      td.textContent = value;
      tr.appendChild(td);
    }
    return tr;
  }

  function showEmpty() {
    statDocs.textContent = "0";
    statChunks.textContent = "0";
    statLast.textContent = "–";
    emptyEl.hidden = false;
    if (tableWrap) tableWrap.hidden = true;
  }


    /* ---------- view boot (phase 76 task 02) ----------
     * The shared header is NOT booted here — in the shell it runs
     * exactly once, via the chat module (app.js) at shell boot. The
     * admin gate reads fetchIsAdmin() — the SAME cached whoami promise
     * header.js exports (zero extra requests): the sync button joins
     * the admin reveal on that one whoami (no extra fetch), and the
     * anonymous branch gates the catalog in / out with NO /api/docs
     * request at all (the Sources-page soft rule, unchanged). */
    const admin = await fetchIsAdmin();
    if (syncBtn) syncBtn.hidden = !admin; // admin-only: ship-hidden, revealed on the same whoami
    if (!admin) {
      // Anonymous: gate in, catalog out, and no /api/docs request at all.
      if (statCards) statCards.hidden = true;
      if (tableWrap) tableWrap.hidden = true;
      if (emptyEl) emptyEl.hidden = true;
      if (gateEl) gateEl.hidden = false;
      return;
    }
    if (gateEl) gateEl.hidden = true;
    loadDocs();
  }