"""Unit: the phase-50 task-04 History contract.

Phase 76 (task 03): the History view is a view of the shell —
``frontend/history.html`` is deleted, its content lives in the shell's
``#view-history`` section, and ``history.js`` is a ``mount(root)`` view
module the router lazy-imports. This module pins the JS/CSS/HTML
markers the view depends on accordingly (the JS pins against
``history.js`` — brace-balanced slices, since phase 76 task 03 the
functions live inside ``mount(root)`` — the HTML pins against the
shell, scoped to the view where view-scoped); the browser behavior
itself is E2E-gated by the story suite (task 05), and a silent
regression is caught without a browser:

* the anonymous no-fetch gate (the gate in, the table out, and the
  single ``GET /api/chats`` fetch lives ONLY in ``loadChats`` —
  unreachable from the anonymous branch);
* the inline two-step Delete (the "Delete? [Yes] [No]" pair, focus to
  Yes, the row kept on No / a failed request, ``Deleted "<title>".``
  on success) and the ``window.confirm`` absence in ``history.js``
  (owner-locked 2026-08-29: no native confirm dialog on this page);
* the ``/?chat=<id>`` Open-link href shape (TODO.md L5 — "return to
  that history with a click");
* ``#nav-history`` on ALL surviving pages (the phase-34 one-bar
  contract — phase 76: the four folded navbar-view files are gone
  (tasks 01–03), so the page list is the shell + the surviving
documents) + ``header.js``'s reveal-for-admin block;
* the full-width table CSS (AGENTS.md rule 5) + the confirm pair +
  the empty-state row;
* the Stale column (phase 53, task 04): the READ-ONLY marker cell in
  ``makeRow`` (the rose ``.stale-pill`` from the row's ``stale`` flag
  + the em-dash fallback, the ``<td>`` aria-label in BOTH states —
  WCAG 2.1 AA, conveyed without the visual), the ``Stale`` ``<th>``
  between Updated and Share in the shell's History view, and the
  ``.stale-pill`` rose-family CSS in ``styles.css``.

The Containerfile stage-1 coverage (the shell copied, the view modules
bundled into the router) is pinned dynamically by
``tests/integration/test_containerfile_assets.py`` — a page or module
missing from stage 1 fails there.
"""
from __future__ import annotations

import re
from pathlib import Path

FRONTEND = Path(__file__).resolve().parents[2] / "frontend"
ASSETS = FRONTEND / "assets"

INDEX_HTML = FRONTEND / "index.html"
DOCUMENT_HTML = FRONTEND / "document.html"
LOGIN_HTML = FRONTEND / "login.html"
SHARED_HTML = FRONTEND / "shared.html"  # phase 51: the anonymous shared page
HISTORY_JS = ASSETS / "history.js"
HEADER_JS = ASSETS / "header.js"
STYLES_CSS = ASSETS / "styles.css"

#: The phase-34 one-bar contract + the shared page.
#: Phase 76 (task 01): the post-shell set — TUNING_HTML dropped (the
#: Tuning view is folded into the shell; its file is deleted).
#: Phase 76 (task 02): SOURCES_HTML + GIT_SOURCES_HTML dropped (both
#: views folded into the shell; both files deleted).
#: Phase 76 (task 03): HISTORY_HTML dropped (the History view is
#: folded into the shell; its file is deleted) — the shell + the
#: surviving documents.
ALL_PAGES = (
    INDEX_HTML,
    DOCUMENT_HTML,
    LOGIN_HTML,
    SHARED_HTML,
)


def _text(path: Path) -> str:
    assert path.is_file(), f"missing frontend file: {path}"
    return path.read_text(encoding="utf-8")


def _js() -> str:
    return _text(HISTORY_JS)


def _css() -> str:
    return _text(STYLES_CSS)


def _shell() -> str:
    return _text(INDEX_HTML)


def _view(html: str) -> str:
    """The shell's History view section — from the #view-history open
    tag to the container main's close (the view is the shell's LAST
    view section, so the slice ends at the first ``</main>`` after
    it)."""
    start = html.find('<section class="view" id="view-history"')
    assert start != -1, "the #view-history section must be in the shell"
    end = html.find("</main>", start)
    assert end != -1, "the container main must close after the view"
    return html[start:end]


def _fn(js: str, name: str) -> str:
    """The source of the first ``function <name>`` in history.js (brace
    balanced — since phase 76 task 03 the functions live inside
    mount(root), so the closing brace is indented, not line-leading;
    the house pin pattern from tests/unit/test_frontend_sync_upload.py).
    """
    fn = js.find(f"function {name}")
    assert fn != -1, f"{name} must be defined in history.js"
    open_idx = js.find("{", fn)
    depth = 0
    for i in range(open_idx, len(js)):
        c = js[i]
        if c == "{":
            depth += 1
        elif c == "}":
            depth -= 1
            if depth == 0:
                return js[fn : i + 1]
    raise AssertionError(f"unbalanced braces in {name}")


def _nav_history_tag(html: str) -> str:
    tag = re.search(r'<a[^>]*id="nav-history"[^>]*>', html)
    assert tag, "the #nav-history link is missing"
    return tag.group(0)


# ---------- the #nav-history link: all surviving pages ----------


def test_nav_history_present_on_all_surviving_pages() -> None:
    """The phase-34 one-bar contract extended by phase 50: the admin-only
    History link SHIPS hidden (revealed by header.js for admin) on every
    standalone page (the shell carries it once for its views — phase 76),
    after the Tuning link, pointing at /history.html. NO page's link is
    statically stamped active: in the shell the router is the SINGLE
    WRITER of the active state (client-side, per view — the old
    history.html page-level stamp is gone with the file), and the
    surviving documents keep their pre-shell no-stamp state."""
    for html in ALL_PAGES:
        text = _text(html)
        tag = _nav_history_tag(text)
        assert 'href="/history.html"' in tag
        assert "hidden" in tag, f"{html.name}: #nav-history must ship hidden"
        # Placed after the Tuning link (the owner-locked position).
        assert text.find('id="nav-tuning"') < text.find('id="nav-history"'), (
            f"{html.name}: #nav-history must follow #nav-tuning"
        )
        assert "is-active" not in tag, (
            f"{html.name}: no statically-current nav link (in the shell the "
            "active state is the router's single-writer job)"
        )
        assert 'aria-current="page"' not in tag


def test_nav_history_count_is_exactly_four_pages() -> None:
    """The pin counting occurrences across ``frontend/*.html`` — exactly
    one ``id="nav-history"`` per page, FOUR pages (phase 51: + the shared
    page; phase 76: the four folded navbar-view files are gone — task 01
    − Tuning, task 02 − RAG + Sources, task 03 − History — the shell's
    ONE link covers all its views), no duplicates and no extra page
    that forgot (or added twice)."""
    total = 0
    for html in sorted(FRONTEND.glob("*.html")):
        count = html.read_text(encoding="utf-8").count('id="nav-history"')
        assert count in (0, 1), f"{html.name}: #nav-history appears {count} times"
        total += count
    assert total == 4, f"expected #nav-history on 4 pages, found {total}"


def test_header_js_reveals_nav_history_for_admin() -> None:
    """header.js reveals #nav-history for admin exactly like
    #nav-tuning — the same ship-hidden / reveal-for-admin contract,
    inside initSharedHeader (null-safe: a page without the link is a
    no-op)."""
    js = _text(HEADER_JS)
    fn = js.find("function initSharedHeader")
    assert fn != -1
    body = js[fn : js.find("\n}", fn)]
    assert 'querySelector("#nav-history")' in body
    assert "navHistory.hidden = !admin" in body


# ---------- the shell's History view: the scaffold ----------


def test_history_view_scaffold_and_landmarks() -> None:
    """The shell's History view (formerly history.html — phase 76 task
    03): the shell's standard landmarks (skip link, the shared header,
    the steering panel + announcer — the shell's ONE header-owned pair,
    the view's copies dropped with the move) + the view section
    (hidden AND inert + focusable — the WCAG pair, AGENTS.md rule 5),
    the page-head, the gate (ship-hidden), the role="status" live
    region, the table inside the .table-wrap card, and the shell's ONE
    footer with the version span (the history page's footer copy is
    dropped — no duplicate #app-version)."""
    html = _shell()
    assert '<a class="skip-link" href="#main">' in html
    assert 'class="app-header"' in html
    assert 'nav class="app-nav" id="app-nav" aria-label="Primary"' in html
    assert html.count('id="steering-panel"') == 1, (
        "the shell carries its ONE steering panel (the view's copy is dropped)"
    )
    assert html.count('id="steering-announcer"') == 1
    assert html.count('<main id="main" class="app-main" tabindex="-1">') == 1
    # The view section: hidden AND inert (the WCAG pair) + focusable.
    view = re.search(r'<section[^>]*id="view-history"[^>]*>', html)
    assert view, "the #view-history section must be in the shell"
    view_tag = view.group(0)
    assert "hidden" in view_tag and "inert" in view_tag, (
        "the folded view ships hidden AND inert"
    )
    assert 'tabindex="-1"' in view_tag, "the target view is focusable"
    body = _view(html)
    assert '<h1>Saved chats</h1>' in body
    # The anonymous gate — the #sources-gate pattern, ship-hidden.
    gate = re.search(r'<section[^>]*id="history-gate"[^>]*>', body)
    assert gate and "hidden" in gate.group(0), "#history-gate must ship hidden"
    assert 'href="/login.html?next=/history.html"' in body, (
        "the gate's Sign in returns to the History view (no-JS fallback)"
    )
    # The action-feedback live region.
    assert re.search(r'<span[^>]*id="history-status"[^>]*role="status"[^>]*>', body)
    # The table wrapper: the .table-wrap card (scrollable) with its
    # own id, a labeled region, focusable.
    wrap = re.search(r'<div[^>]*class="table-wrap history-table-wrap"[^>]*>', body)
    assert wrap, "the table must live in the .table-wrap card"
    assert 'id="history-table-wrap"' in wrap.group(0)
    assert 'role="region"' in wrap.group(0) and 'tabindex="0"' in wrap.group(0)
    # The shell keeps its ONE footer with the version span (the history
    # page's footer copy is dropped — no duplicate #app-version).
    assert 'class="footer-version" id="app-version"' in html
    assert html.count('id="app-version"') == 1


def test_history_table_skeleton() -> None:
    """The table skeleton: ``.history-table`` with the six columns —
    Title | Messages | Updated | Stale (phase 53) | Share (phase 51) |
    Actions (the Actions header text is visually-hidden — the row
    buttons carry their own aria-labels) — and the empty-state row
    (ship-hidden, the exact copy). Phase 76 (task 03): scoped to the
    shell's History view section."""
    html = _view(_shell())
    assert '<table class="history-table">' in html
    for col in ('<th scope="col">Title</th>', '<th scope="col">Messages</th>',
                '<th scope="col">Updated</th>', '<th scope="col">Stale</th>',
                '<th scope="col">Share</th>'):
        assert col in html
    # The Stale column (phase 53) sits BETWEEN Updated and Share —
    # i.e. between Updated and Actions — so the phase-51 contract
    # (Share between Updated and Actions) still holds.
    assert (
        html.find('<th scope="col">Updated</th>')
        < html.find('<th scope="col">Stale</th>')
        < html.find('<th scope="col">Share</th>')
        < html.find('visually-hidden">Actions')
    ), "the Stale column must sit between Updated and Share"
    actions_th = re.search(
        r'<th scope="col">([^<]*)<span class="visually-hidden">Actions</span></th>',
        html,
    )
    assert actions_th, "the Actions column header must be visually-hidden text"
    assert actions_th.group(1) == "", "no visible text beside the hidden header"
    # The empty-state row: ship-hidden, colspan 6 (phase 51 added
    # Share, phase 53 added Stale), the exact copy.
    row = re.search(r'<tr[^>]*class="history-empty-row"[^>]*>', html)
    assert row, "the empty-state row must ship in the skeleton"
    assert "hidden" in row.group(0)
    assert 'id="history-empty-row"' in row.group(0)
    assert "<td colspan=\"6\">" in html
    # Phase 66 (owner-locked A3, 2026-09-01): the auto-save copy —
    # the Save button is retired (phase 55), every conversation
    # saves itself; the old "press Save" line is gone.
    assert (
        "No saved chats yet — start a conversation and it will be saved automatically."
    ) in html


def test_shell_scripts_and_no_cdn() -> None:
    """Shell script load order (the house pattern): brand.js classic
    FIRST, the app.js (chat) + router.js modules, NO direct history.js
    <script> tag (single-evaluation design — the router lazy-imports
    the view module on first show; in the image the Containerfile's
    esbuild stage inlines it into the router bundle). history.js keeps
    its relative shared-header import (it uses the cached whoami
    promise). No-CDN rule (AGENTS.md rule 6): no external
    script/link tags."""
    html = _shell()
    srcs = re.findall(r'<script[^>]*src="([^"]+)"', html)
    assert srcs[0] == "assets/brand.js", "brand.js (classic) must load first"
    assert "/assets/app.js" in srcs, "the shell loads the chat module"
    assert "/assets/router.js" in srcs, "the shell loads the router module"
    assert [s for s in srcs if "history.js" in s] == [], (
        "no direct history.js tag — the router lazy-imports the view module"
    )
    js = _js()
    assert 'from "./header.js"' in js, (
        "history.js must import the shared header module relatively"
    )
    assert '"/assets/header.js"' not in js
    assert 'src="http' not in html and 'href="http' not in html, (
        "no CDN: every asset is local (AGENTS.md rule 6)"
    )


# ---------- the anonymous no-fetch gate ----------


def test_anonymous_boot_makes_no_chats_request() -> None:
    """The whoami gate in ``mount(root)`` (phase 76 task 03 — the shell
    view module form): the view module does NOT boot the shared header
    (the shell's header boots exactly once, via the chat module
    (app.js) at shell boot — no call site, and the import carries ONLY
    the cached whoami promise), so the anonymous branch gates on
    ``fetchIsAdmin()`` alone (the SAME cached /api/whoami request —
    zero extra), hides the table, shows the gate, and RETURNS — no
    ``/api/chats`` request on the wire (the router 403s anonymous; the
    story E2E pins the request log). Only the admin path reaches
    ``loadChats()``. The single ``fetch("/api/chats")`` in the file
    lives in loadChats."""
    js = _js()
    assert js.count('fetch("/api/chats")') == 1, (
        "exactly ONE list fetch — the anonymous path must never add one"
    )
    load = _fn(js, "loadChats")
    assert 'fetch("/api/chats")' in load, "the list fetch lives in loadChats"

    # Phase 76 (task 03): the view module never boots the shell's
    # header — no CALL to the header boot (a docstring may name it;
    # a call may not) and no initSharedHeader in the import — the
    # shell's header boots via the chat module (app.js) at shell boot.
    assert "await initSharedHeader()" not in js, (
        "the view must not re-boot the shell's header"
    )
    import_lines = [line for line in js.splitlines() if line.strip().startswith("import")]
    assert all("initSharedHeader" not in line for line in import_lines), (
        "the view must not import the header boot — the shell's header boots "
        "via the chat module (app.js) at shell boot"
    )
    assert 'import { fetchIsAdmin } from "./header.js";' in js, (
        "the view imports ONLY the shared cached whoami promise"
    )
    mount_i = js.find("export async function mount(root)")
    assert mount_i != -1, "mount(root) must be the module's entry"
    gate_i = js.find("if (!(await fetchIsAdmin()))")
    assert gate_i > mount_i, "the whoami gate must run in mount"
    # The anonymous branch: gate in, table out, then a bare return —
    # and NO fetch call anywhere inside it.
    branch = js[gate_i : js.find("return;", gate_i)]
    assert "fetch(" not in branch, "the anonymous branch must not fetch anything"
    assert "tableWrap.hidden = true" in branch
    assert "gateEl.hidden = false" in branch
    # The admin path: the gate hides, then the list loads.
    after = js[js.find("return;", gate_i):]
    assert "gateEl.hidden = true" in after
    assert "loadChats();" in after


def test_admin_load_renders_rows_or_empty_state() -> None:
    """loadChats: a 0-row fetch (and non-2xx / a network failure)
    reveals the empty-state row; a populated fetch renders one row per
    chat, in the server's order (latest activity first)."""
    js = _js()
    load = _fn(js, "loadChats")
    # Every no-data outcome lands on the empty state.
    assert load.count("showEmptyState()") == 3, (
        "network failure, non-2xx and a 0-row list all show the empty state"
    )
    assert "chats.length" in load
    assert "makeRow(chat)" in load
    empty = _fn(js, "showEmptyState")
    assert "emptyRow.hidden = false" in empty


# ---------- the /?chat=<id> Open link ----------


def test_open_link_is_the_title_with_chat_href() -> None:
    """makeRow: the Title cell is the Open link — ``/?chat=<id>``
    ("return to that history with a click", TODO.md L5) — rendered
    through textContent (the auto-title is user-derived; never
    innerHTML). The Updated cell carries the locale date+time with the
    full ISO in the title attribute; Messages is the message_count."""
    js = _js()
    row = _fn(js, "makeRow")
    assert 'link.href = "/?chat=" + chat.id' in row, (
        "the Open link returns to /?chat=<id> (task 03's boot load)"
    )
    assert 'link.className = "history-title-link"' in row
    assert "link.textContent = chat.title" in row, "XSS contract: textContent only"
    assert 'innerHTML' not in row, "makeRow must never build HTML"
    assert "String(chat.message_count)" in row
    assert "updatedTd.title = chat.updated_at" in row, "full ISO on hover"
    assert "fmtDate(chat.updated_at)" in row
    assert "link.title" in row or "titleTd.title = chat.title" in row


# ---------- the inline two-step Delete ----------


def test_two_step_delete_confirm_pair() -> None:
    """makeDeleteControl: the first click swaps the Delete button for
    the "Delete? [Yes] [No]" pair IN PLACE (keyboard-reachable — focus
    moves to Yes); No restores the Delete button (focus returns); the
    Delete button carries a labeled aria-name."""
    js = _js()
    # Owner-locked 2026-08-29: no native confirm dialog in the file.
    assert "window.confirm" not in js, "history.js must use the inline two-step only"
    fn = _fn(js, "makeDeleteControl")
    assert 'del.className = "history-delete"' in fn
    assert 'del.setAttribute("aria-label", `Delete saved chat: ${chat.title}`)' in fn
    assert 'label.textContent = "Delete?"' in fn
    assert 'yes.className = "history-confirm-yes"' in fn
    assert 'no.className = "history-confirm-no"' in fn
    # The shipped state of the actions cell IS the Delete button
    # (before any click) — a cell that only gains the button on
    # restore would render an empty Actions column.
    append = fn.find("cell.appendChild(del)")
    ret = fn.rfind("return cell")
    assert -1 < append < ret, "the Delete button is appended before the return"
    # The swap + the focus handoff.
    assert "cell.replaceChildren(label, yes, no)" in fn
    yes_swap = fn.find("cell.replaceChildren(label, yes, no)")
    assert fn.find("yes.focus()", yes_swap) > 0, "focus moves to Yes after the swap"
    # No (and the restore helper) bring the Delete button back, focused.
    # (Brace-balanced — since phase 76 task 03 the helper lives inside
    # mount(root), so a line-leading-brace slice would not find it.)
    restore = _fn(js, "restoreDelete")
    assert "cell.replaceChildren(del)" in restore
    assert "del.focus()" in restore
    assert 'no.addEventListener("click", restoreDelete)' in fn


def test_confirmed_delete_outcomes() -> None:
    """confirmDelete: double-fire guarded; 2xx → the row is removed +
    the empty-state row reappears when it was the last + the live
    region `Deleted "<title>".`; a 404 (already gone) drops the stale
    row and says so; any other failure / a network error KEEPS the row
    (restore) and lands the error line."""
    js = _js()
    fn = _fn(js, "confirmDelete")
    assert "yesBtn.disabled = true" in fn
    assert "fetch(`/api/chats/${chat.id}`, { method: \"DELETE\" })" in fn
    # Success: remove + empty-state check + the exact live-region line.
    assert "row.remove()" in fn
    assert "showEmptyIfLast()" in fn
    assert 'announce(`Deleted "${chat.title}".`)' in fn
    # 404: the row is stale — drop it, no restore. (The branch slices
    # stop at the NEXT branch boundary — a template-literal `}` inside
    # an announce line must not end the slice early.)
    nf = fn.find("r.status === 404")
    assert nf != -1, "the 404 branch must be handled"
    notok = fn.find("if (!r.ok)")
    nf_branch = fn[nf:notok]
    assert "row.remove()" in nf_branch
    assert "already deleted" in nf_branch
    assert "restoreDelete()" not in nf_branch
    # !ok (non-404) and network: the row stays, the button is
    # retryable, and the error line lands.
    # !ok (non-404) and network: the row stays, the button is
    # retryable, and the error line lands. (The try/catch wraps the
    # FETCH, so it precedes the status branches; the !ok slice runs to
    # the function's close — the success tail after it carries neither
    # a restore nor that line.)
    assert notok != -1
    notok_branch = fn[notok:]
    assert "restoreDelete()" in notok_branch
    assert "try again" in notok_branch
    # The network-error catch: the reachable? line + the restore (the
    # catch wraps the fetch, so it precedes the status branches).
    catch_i = fn.find("} catch {")
    assert catch_i != -1
    catch_branch = fn[catch_i : fn.find("if (r.status === 404)")]
    assert "is the app reachable?" in catch_branch
    assert "restoreDelete()" in catch_branch
    # The empty-state row reappears exactly when the last data row is
    # gone (the hidden empty row itself ships in the tbody).
    empty = _fn(js, "showEmptyIfLast")
    assert "querySelectorAll(\"tr\").length > 1" in empty


# ---------- the table CSS ----------


def test_history_table_css_full_width_and_palette() -> None:
    """styles.css: .history-table is the full-width sources-table family
    (width 100%, --line borders, the brand-soft thead, row hover); the
    title link is the accent link (brand-ink, focus-visible); the
    confirm pair is Yes-on-error-rose + No-ghost; the empty-state row
    is the muted centered message. Every pair is Phase-08 AA
    (brand-ink/brand-soft 6.9:1, err 9.1:1, ink-soft >=6.9:1)."""
    css = _css()
    block = re.search(r"\.history-table \{([\s\S]*?)\n\}", css)
    assert block, "styles.css must style .history-table"
    body = block.group(1)
    assert "width: 100%" in body, "the table is FULL-WIDTH (AGENTS.md rule 5)"
    assert "min-width: 640px" in body
    th = re.search(r"\.history-table th \{([\s\S]*?)\n\}", css)
    assert th and "var(--brand-soft)" in th.group(1) and "var(--brand-ink)" in th.group(1)
    hover = re.search(r"\.history-table tbody tr:hover \{([^}]*)\}", css)
    assert hover, "row hover is part of the table family"
    link = re.search(r"\.history-title-link \{([\s\S]*?)\n\}", css)
    assert link and "var(--brand-ink)" in link.group(1), "the Open link is the accent link"
    assert re.search(r"\.history-title-link:focus-visible \{[^}]*outline[^}]*3px", css), (
        "the Open link keeps a :focus-visible outline"
    )
    yes = re.search(r"\.history-confirm-yes \{([\s\S]*?)\n\}", css)
    assert yes, "the confirm Yes button must be styled"
    ybody = yes.group(1)
    assert "var(--err-bg)" in ybody and "var(--err-ink)" in ybody and "var(--err-line)" in ybody
    no = re.search(r"\.history-confirm-no \{([\s\S]*?)\n\}", css)
    assert no and "background: transparent" in no.group(1), "No is the ghost"
    empty = re.search(r"\.history-empty-row td \{([\s\S]*?)\n\}", css)
    assert empty, "the empty-state row must be styled"
    ebody = empty.group(1)
    assert "text-align: center" in ebody and "var(--ink-soft)" in ebody


def test_history_table_mobile_behavior() -> None:
    """≤640px (the phase-07 responsive contract): the table keeps its
    full width (the .table-wrap's horizontal scroll already covers
    it) and the actions cell wraps so the two-step confirm pair fits
    the phone width."""
    css = _css()
    mobile = re.search(r"@media \(max-width: 640px\) \{([\s\S]*?)\n\}\n", css)
    assert mobile, "the mobile media query must exist"
    mbody = mobile.group(1)
    assert ".history-actions-cell { white-space: normal; }" in mbody
    assert ".history-actions { flex-wrap: wrap; }" in mbody


# ---------- the Share column (phase 51, owner-locked 2026-08-29) ----------


def test_make_row_inserts_share_cell_between_updated_and_actions() -> None:
    """makeRow: the Share <td> (with the share control) lands BETWEEN
    the Updated cell and the Actions cell — the column order in
    history.html is Title | Messages | Updated | Stale (phase 53) |
    Share | Actions."""
    js = _js()
    row = _fn(js, "makeRow")
    updated_i = row.find('updatedTd.className = "history-updated-cell"')
    stale_i = row.find('staleTd.className = "history-stale-cell"')
    share_i = row.find('shareTd.className = "history-share-cell"')
    actions_i = row.find('actionsTd.className = "history-actions-cell"')
    assert -1 < updated_i < stale_i < share_i < actions_i, (
        "the stale cell (phase 53) must sit between Updated and Share —"
        " i.e. the share cell must still sit between Updated and Actions"
    )
    assert "makeShareControl(chat)" in row
    seq = re.findall(r"tr\.appendChild\((\w+)\)", row)
    assert seq == [
        "titleTd", "countTd", "updatedTd", "staleTd", "shareTd", "actionsTd",
    ], f"row cell order must be title/count/updated/stale/share/actions, got {seq}"


# ---------- the Stale column (phase 53, task 04) ----------


def test_stale_cell_branches_on_row_flag_with_aria_label() -> None:
    """makeRow (phase 53 task 04): the Stale cell renders from the
    row's ``stale`` flag — the SERVER computes staleness (task 03),
    the client never does version math. Stale rows: the rose
    ``.stale-pill`` (the ``Stale`` text + the EXACT hover copy pointing
    at the Regenerate action on the chat page, task 05). Fresh rows:
    a plain em-dash (no pill). The <td> carries its own aria-label in
    BOTH states (WCAG 2.1 AA — the marker must be conveyed without the
    visual). READ-ONLY badge: the cell binds no events and creates no
    controls (the Regenerate button lives on the chat-page banner);
    textContent only (XSS contract)."""
    js = _js()
    row = _fn(js, "makeRow")
    assert 'staleTd.className = "history-stale-cell"' in row
    assert "tr.appendChild(staleTd)" in row
    assert "if (chat.stale)" in row, "the cell branches on the row's stale flag"
    branch = row[row.find("if (chat.stale)") : row.find("tr.appendChild(staleTd)")]
    # The stale branch: the rose pill with the exact hover copy.
    assert 'pill.className = "stale-pill"' in branch
    assert 'pill.textContent = "Stale"' in branch
    assert (
        'pill.title = "Sources have changed since this chat was saved'
        " — open the chat to Regenerate\";"
    ) in branch, "the pill's hover copy points at the Regenerate action (task 05)"
    # The fresh branch: the plain em-dash, never the pill.
    else_i = branch.find("} else {")
    assert else_i != -1, "the fresh branch must exist"
    fresh = branch[else_i:]
    assert 'staleTd.textContent = "—"' in fresh, "fresh rows render the em-dash"
    assert "stale-pill" not in fresh, "fresh rows render the em-dash, not the pill"
    # The <td> aria-label ships in BOTH states (conveyed without the
    # visual — WCAG 2.1 AA).
    assert branch.count('staleTd.setAttribute("aria-label"') == 2, (
        "the cell's aria-label must exist in the stale AND the fresh branch"
    )
    # READ-ONLY: no events, no controls, no innerHTML anywhere in the
    # cell's construction.
    assert "addEventListener" not in branch
    assert "createElement(\"button\")" not in branch
    assert "innerHTML" not in branch


def test_stale_column_css_rose_family() -> None:
    """styles.css (phase 53 task 04): ``.stale-pill`` is the rose
    family — the Stop-treatment tokens (err-ink on err-bg ≈9.3:1, the
    err-line border), theme-token based so it stays AA with the
    palette; a compact rounded pill (border-radius 999px, nowrap). The
    ``.history-stale-cell`` keeps the marker on one line and rides
    ink-soft (5.1:1 on --surface) for the fresh rows' em-dash."""
    css = _css()
    pill = re.search(r"\.stale-pill \{([\s\S]*?)\n\}", css)
    assert pill, "styles.css must style .stale-pill"
    body = pill.group(1)
    assert "background: var(--err-bg)" in body, "the Stop-treatment tokens"
    assert "color: var(--err-ink)" in body
    assert "border: 1px solid var(--err-line)" in body
    assert "border-radius: 999px" in body, "the pill shape"
    assert "white-space: nowrap" in body
    cell = re.search(r"\.history-stale-cell \{([^}]*)\}", css)
    assert cell, "the stale cell must be styled"
    cbody = cell.group(1)
    assert "white-space: nowrap" in cbody
    assert "var(--ink-soft)" in cbody, "the em-dash rides ink-soft (AA on --surface)"


def test_share_control_three_states_and_two_step_unshare() -> None:
    """The share cell's THREE states — unshared → [Create link];
    shared → [Copy] [Unshare]; confirming → "Unshare? [Yes] [No]" —
    plus the inline two-step unshare (the phase-50 Delete-confirm
    pattern: focus moves to Yes, No restores the shared state, no
    native dialog). The shipped state comes from the row's share_url
    (the list endpoint populates it — no second fetch)."""
    js = _js()
    assert "window.confirm" not in js, "history.js must use the inline two-step only"
    # makeShareControl: the shipped state branches on chat.share_url.
    make = _fn(js, "makeShareControl")
    assert "cell.className = \"history-share\"" in make
    assert "chat.share_url" in make
    assert "renderShareShared(chat, cell)" in make
    assert "renderShareUnshared(chat, cell)" in make
    # Unshared state: the Create link button (labeled, textContent).
    unshared = _fn(js, "renderShareUnshared")
    assert 'create.className = "history-share-create"' in unshared
    assert 'create.textContent = "Create link"' in unshared
    assert 'create.setAttribute("aria-label", `Create share link: ${chat.title}`)' in unshared
    assert "innerHTML" not in unshared, "XSS contract: textContent only"
    # Shared state: Copy + Unshare, then the two-step confirm.
    shared = _fn(js, "renderShareShared")
    assert 'copy.className = "history-share-copy"' in shared
    assert 'copy.textContent = "Copy"' in shared
    assert 'unshare.className = "history-unshare"' in shared
    assert 'unshare.textContent = "Unshare"' in shared
    assert 'label.textContent = "Unshare?"' in shared
    assert 'yes.className = "history-confirm-yes"' in shared, (
        "the unshare two-step reuses the phase-50 .history-confirm-* pair"
    )
    assert 'no.className = "history-confirm-no"' in shared
    assert "cell.replaceChildren(label, yes, no)" in shared
    swap_i = shared.find("cell.replaceChildren(label, yes, no)")
    assert shared.find("yes.focus(", swap_i) > 0, "focus moves to Yes after the swap"
    assert 'no.addEventListener("click", restoreShared)' in shared
    restore_i = shared.find("function restoreShared")
    assert restore_i != -1
    assert "cell.replaceChildren(copy, unshare)" in shared[restore_i:restore_i + 120], (
        "No (and a failed request) restore the shared state"
    )


def test_share_create_and_unshare_request_outcomes() -> None:
    """createShareLink: POST /api/chats/<id>/share → the response's
    share_url becomes the row's data, the cell re-renders shared, and
    the ABSOLUTE link is offered for copying (clipboard → fallback);
    non-2xx / network keep the unshared state (retryable) + the error
    line. confirmUnshare: POST /api/chats/<id>/unshare → the cell
    re-renders unshared + `Unshared "<title>".`; non-2xx / network
    restore the shared state + the error line. Both double-fire
    guarded."""
    js = _js()
    create = _fn(js, "createShareLink")
    assert "createBtn.disabled = true" in create
    assert 'fetch(`/api/chats/${chat.id}/share`, { method: "POST" })' in create
    assert "renderShareShared(chat, cell)" in create, "success re-renders the shared state"
    assert "chat.share_url = share_url" in create, "the row's data gains the link"
    assert "new URL(share_url, window.location.origin).toString()" in create, (
        "the ABSOLUTE link is what gets copied (the origin supplies scheme/host)"
    )
    assert (
        'announce(copied ? "Share link copied."'
        ' : "Share link ready — copy it from the field.")'
    ) in create
    assert "is the app reachable?" in create, "the network-error line"
    assert "try again" in create, "the non-2xx line"
    # A failed request keeps the button (re-enabled) — retryable.
    assert create.count("createBtn.disabled = false") == 2, (
        "both failure paths re-enable the Create link button"
    )
    unshare = _fn(js, "confirmUnshare")
    assert "yesBtn.disabled = true" in unshare
    assert 'fetch(`/api/chats/${chat.id}/unshare`, { method: "POST" })' in unshare
    assert "chat.share_url = null" in unshare, "a revoked link drops the row's share_url"
    assert "renderShareUnshared(chat, cell)" in unshare, "success re-renders the unshared state"
    assert 'announce(`Unshared "${chat.title}".`)' in unshare
    assert unshare.count("restoreShared()") == 2, (
        "non-2xx and network both restore the shared state (retryable)"
    )
    assert "is the app reachable?" in unshare
    assert "try again" in unshare


def test_share_copy_uses_own_per_page_clipboard_helper_with_fallback() -> None:
    """The per-page duplication house style: history.js keeps its OWN
    ~10-line copy of the clipboard + inline-link fallback helper (no
    import from app.js, no new shared module). A non-secure (http)
    origin rejects navigator.clipboard → a transient .share-link-fallback
    <a> field lands in the row's share cell (selects its full URL on
    focus — the range-based selectAllInField), one field at a time."""
    js = _js()
    import_lines = [line for line in js.splitlines() if line.strip().startswith("import")]
    assert all("app.js" not in line for line in import_lines), (
        "no cross-page import — the helper is duplicated per page"
    )
    copy = _fn(js, "copyShareLink")
    assert "navigator.clipboard.writeText(absoluteUrl)" in copy, "the clipboard try"
    assert 'cell.querySelectorAll(".share-link-fallback").forEach((el) => el.remove())' in copy, (
        "one field at a time — a new offer replaces the old"
    )
    assert 'field.className = "share-link-fallback"' in copy
    assert "field.href = absoluteUrl" in copy
    assert "field.textContent = absoluteUrl" in copy, "XSS contract: textContent only"
    assert 'field.addEventListener("focus", () => selectAllInField(field))' in copy
    assert "field.focus({ preventScroll: true })" in copy, "selects the URL on focus"
    sel = _fn(js, "selectAllInField")
    assert "document.createRange()" in sel and "selectNodeContents(el)" in sel
    # Copy (shared state) goes through the same helper.
    rowcopy = _fn(js, "copyRowShareLink")
    assert "copyShareLink(" in rowcopy
    assert (
        'announce(copied ? "Share link copied."'
        ' : "Share link ready — copy it from the field.")'
    ) in rowcopy


def test_share_column_css() -> None:
    """styles.css: the Share cell's ghost buttons (the Tune/Retry family
    — transparent, --line border, ink-soft, ≥44px) + Unshare's
    error-rose hover (it revokes — the Delete language) + the inline
    fallback field (input-like: mono, surface fill, --line border,
    ellipsis, 3px focus-visible). The unshare two-step reuses the
    .history-confirm-* pair CSS (no new confirm styles)."""
    css = _css()
    for cls in (".history-share-create", ".history-share-copy", ".history-unshare"):
        assert re.search(re.escape(cls), css), f"styles.css must style {cls}"
    btn = re.search(
        r"\.history-share-create,\n\.history-share-copy,\n\.history-unshare \{([\s\S]*?)\n\}",
        css,
    )
    assert btn, "the share buttons share one ghost-button block"
    body = btn.group(1)
    assert "min-height: 44px" in body, "≥44px comfortable target"
    assert "border: 1px solid var(--line)" in body
    assert "background: transparent" in body
    assert "var(--ink-soft)" in body
    assert (
        ".history-unshare:hover:not(:disabled) { background: var(--err-bg);"
        " color: var(--err-ink); border-color: var(--err-line); }"
    ) in css, "Unshare hovers the error rose (it revokes the link)"
    field = re.search(r"\.share-link-fallback \{([\s\S]*?)\n\}", css)
    assert field, "the inline fallback field must be styled"
    fbody = field.group(1)
    assert "var(--mono)" in fbody, "input-like: mono (the URL is data)"
    assert "background: var(--surface)" in fbody
    assert "border: 1px solid var(--line)" in fbody
    assert "text-overflow: ellipsis" in fbody
    assert re.search(r"\.share-link-fallback:focus-visible \{[^}]*outline[^}]*3px", css), (
        "the fallback field keeps a 3px :focus-visible outline"
    )