"""Phase 58 E2E (Playwright): the 2x reading column on wide desktops —
measured bounding-box widths, not CSS pins.

TODO.md L5 (owner instruction 2026-08-31, roadmap confirmation D2 +
expansion): "The chat response needs to be 2x wider on wide desktops.
there's a lot of unused space." — extended to the document view. The
owner-locked contract: viewport >=1500px doubles ``--chat-column`` to
92rem (1472px at the 16px root) for the four reading shells —
``.chat-shell``, ``.shared-shell``, ``.doc-md`` and
``.doc-summary:has(+ .doc-md)`` — while everything below the breakpoint
renders exactly as before (46rem / 736px) and ``.tuning-shell`` (a
form, not a reading surface) never widens (CSS-pinned by the unit
suite, task 01 — the browser proof of the MEASURED width is this file).

Run in isolation (DB must be up: ``podman compose up -d db``):

    uv run pytest tests/e2e/test_wide_desktop_column.py -v --no-cov

Test → contract mapping:

1. ``test_chat_column_wide_vs_base`` — ``/`` at 1920×1080: the
   ``.chat-shell`` bounding box is 1472px (92rem, ±4px) and centered;
   at 1280×800 (below the wide breakpoint) it is back to 736px
   (46rem, ±4px).
2. ``test_document_column_wide_vs_base`` — a seeded markdown document
   that carries a summary: at 1920 both ``.doc-md`` and the adjacent
   ``.doc-summary:has(+ .doc-md)`` panel are 1472px; at 1280
   ``.doc-md`` is 736px.
3. ``test_shared_column_wide`` — a real auto-saved conversation shared
   by token: ``/shared/<token>`` at 1920 renders ``.shared-shell`` at
   1472px in a fresh anonymous context.
4. ``test_narrow_unchanged`` — 360px: no horizontal overflow and the
   ``.chat-shell`` is the existing mobile rule — full-bleed at the
   viewport width (the shell IS its .container; the 0.9rem mobile
   gutters live in its own padding, inside the measured box), 900px:
   the shell holds the 46rem base (736px, not the 1472px wide rule —
   at 900px a leaked wide override would pin the shell to the 860px
   content box instead, so 736px is the discriminator) — the wide
   rule does not leak below 1500px.

DB isolation: the shared-chat row is deleted in a ``finally`` (admin
cookie — the house pattern of test_share_chat.py, whose distinctive
question text keeps the auto-title unique); the fixture document rows
follow the story-fixture convention of the sibling suites (truncate +
re-import; the summary document is a direct row insert, the
test_document_viewer.py XSS-fixture pattern — the viewer is
database-only).
"""
from __future__ import annotations

import asyncio
import re
import time
from datetime import UTC, datetime
from pathlib import Path
from threading import Thread
from typing import Any

import httpx
from playwright.sync_api import Browser, Page, ViewportSize, expect
from sqlalchemy import text

from app.config import Settings
from app.db import SessionLocal
from app.models import Document
from app.rag.importer import ImportSummary, import_sources
from app.rag.llm import LLMClient
from e2e.auth_helpers import login

REPO = Path(__file__).resolve().parents[2]
FIXTURES = REPO / "tests" / "fixtures" / "docs"

# The two proof viewports (task spec): wide desktop vs just below the
# 1500px breakpoint, at the 16px root the phase-58 rem contract:
# 92rem = 1472px, 46rem = 736px. ±4px tolerance (task spec).
WIDE_PX = 92 * 16  # 1472px — the 2x wide override (>=1500px)
BASE_PX = 46 * 16  # 736px — the --chat-column base
TOL_PX = 4
WIDE_VIEWPORT: ViewportSize = {"width": 1920, "height": 1080}
BASE_VIEWPORT: ViewportSize = {"width": 1280, "height": 800}

MOCK_ANSWER_MARKER = "Deterministic mock answer for E2E"
SHARE_URL_RE = re.compile(r"^/shared/[0-9a-f-]{36}$")

#: The seeded markdown document (direct row insert — the viewer is
#: database-only, so no fixture file is needed). Encoded viewer URL
#: values: slashes come out as %2F, same as the chips build them.
FIXTURE_SOURCE = "docs"
FIXTURE_PATH = "notes/wide-column-fixture.md"
FIXTURE_TITLE = "Wide Column Fixture"
FIXTURE_DOC_URL = "/document.html?source=docs&path=notes%2Fwide-column-fixture.md"


# ---------------------------------------------------------------------------
# KB seeding (house pattern — test_document_viewer.py / test_share_chat.py)
# ---------------------------------------------------------------------------


async def _import_fixtures(mock_port: int) -> ImportSummary:
    kwargs: dict[str, Any] = {"_env_file": None, "llm_base_url": f"http://127.0.0.1:{mock_port}/v1"}
    settings = Settings(**kwargs)  # pyright: ignore[reportCallIssue]
    return await import_sources([FIXTURES], LLMClient(settings))


def _run_in_thread(coro: Any) -> Any:
    """Run a coroutine on a worker thread.

    Playwright's sync API keeps an asyncio loop running on the test
    thread, so ``asyncio.run`` cannot be called directly from a test
    body.
    """
    box: dict[str, Any] = {}

    def runner() -> None:
        try:
            box["value"] = asyncio.run(coro)
        except BaseException as e:  # noqa: BLE001 — re-raised on the test thread
            box["error"] = e

    t = Thread(target=runner)
    t.start()
    t.join()
    if "error" in box:
        raise box["error"]
    return box["value"]


def _reset_db(mock_port: int, seed: bool) -> ImportSummary | None:
    """Truncate the KB (and query log + steering notes — deterministic
    mock answers), then optionally re-import fixtures. ``saved_chats``
    is deliberately NOT touched: the shared test cleans up its own
    row in a ``finally``."""
    with SessionLocal() as db:
        db.execute(text("TRUNCATE chunks, documents, query_log, steering_notes"))
        db.commit()
    if not seed:
        return None
    return _run_in_thread(_import_fixtures(mock_port))


def _seed_summary_doc() -> None:
    """One markdown document carrying a stored summary — the ONLY shape
    that renders both reading-column pins on one page: ``.doc-summary``
    (the phase-36 panel) directly above ``.doc-md`` (the ``:has(
    + .doc-md)`` sibling match). Direct row insert — the viewer is
    database-only (the test_document_viewer.py XSS-fixture pattern)."""
    with SessionLocal() as db:
        db.add(
            Document(
                source=FIXTURE_SOURCE,
                path=FIXTURE_PATH,
                full_path="/tmp/wide-column-fixture.md",
                title=FIXTURE_TITLE,
                content=(
                    "# Wide Column Fixture\n\n"
                    "Phase-58 width pin: a markdown document with a "
                    "summary, so the viewer renders the .doc-summary "
                    "panel directly above the .doc-md column."
                ),
                summary="A phase-58 fixture summary for the wide-column pin.",
                content_hash="w" * 64,
                indexed_at=datetime.now(UTC),
            )
        )
        db.commit()


# ---------------------------------------------------------------------------
# Measurement + chat-turn helpers
# ---------------------------------------------------------------------------


def _assert_width(page: Page, selector: str, expected_px: int, label: str) -> None:
    """The element's bounding-box width is ``expected_px`` ±4px (task
    spec) — the measured rendered width, not the computed style."""
    box = page.locator(selector).first.bounding_box()
    assert box is not None, f"{selector} not rendered ({label})"
    assert abs(box["width"] - expected_px) <= TOL_PX, (
        f"{label}: {selector} is {box['width']:.1f}px, "
        f"want {expected_px}px ±{TOL_PX}px"
    )


def _assert_centered(page: Page, selector: str, viewport_w: int, label: str) -> None:
    """margin-inline: auto — the column center is within ±2% of the
    viewport center (the test_responsive_polish.py assertion style)."""
    box = page.locator(selector).first.bounding_box()
    assert box is not None, f"{selector} not rendered ({label})"
    center = box["x"] + box["width"] / 2
    assert abs(center - viewport_w / 2) <= 0.02 * viewport_w, (
        f"{label}: {selector} center {center:.1f}px is not within ±2% of "
        f"the {viewport_w}px viewport center"
    )


def _doc_overflow(page: Page) -> tuple[int, int]:
    """(scrollWidth, clientWidth) of the documentElement."""
    return page.evaluate(
        "() => [document.documentElement.scrollWidth, document.documentElement.clientWidth]"
    )  # pyright: ignore[reportReturnType]


def _assert_no_doc_overflow(page: Page, label: str) -> None:
    scroll, client = _doc_overflow(page)
    assert scroll <= client, f"horizontal overflow at {label}: {scroll} > {client}"


def _ask(page: Page, question: str) -> None:
    """Send one turn and wait until the grounded answer has fully
    landed (the ``done`` event restored the Send button)."""
    page.fill("#message-input", question)
    page.click("#send-btn")
    expect(page.locator(".msg.user .bubble").last).to_contain_text(question)
    expect(page.locator(".msg.brain .bubble").last).to_contain_text(
        MOCK_ANSWER_MARKER, timeout=30_000
    )
    expect(page.locator("#send-btn")).to_be_enabled()
    expect(page.locator("#send-label")).to_have_text("Send")


def _admin_cookies(page: Page) -> dict[str, str]:
    """The signed session cookies the browser holds after a form login."""
    return {
        c["name"]: c["value"]
        for c in page.context.cookies()
        if "name" in c and "value" in c
    }


def _auto_title(question: str) -> str:
    """The phase-50 auto-title convention: the first question,
    whitespace-collapsed, capped at 120 chars."""
    return " ".join(question.split())[:120]


def _chats(app_url: str, cookies: dict[str, str]) -> list[dict[str, Any]]:
    r = httpx.get(f"{app_url}/api/chats", timeout=10, cookies=cookies)
    assert r.status_code == 200
    return r.json()["chats"]


def _wait_saved_row(
    app_url: str,
    cookies: dict[str, str],
    title: str,
    messages: int = 2,
) -> dict[str, Any]:
    """Wait for the auto-saved row (phase 55: auto-saves are SILENT —
    poll the admin list until the row with the auto-title appears with
    the expected message count)."""
    deadline = time.monotonic() + 15
    last: dict[str, Any] | None = None
    while time.monotonic() < deadline:
        last = next(
            (c for c in _chats(app_url, cookies) if c["title"] == title), None
        )
        if last is not None and last["message_count"] >= messages:
            return last
        time.sleep(0.2)
    raise AssertionError(f"no auto-saved row for {title!r} (last: {last!r})")


def _delete_chat(app_url: str, cookies: dict[str, str], chat_id: str) -> None:
    """Best-effort row cleanup (a 404 — already deleted — is fine)."""
    httpx.delete(f"{app_url}/api/chats/{chat_id}", timeout=10, cookies=cookies)


# ---------------------------------------------------------------------------
# 1. Chat: 1472px at 1920, back to 736px at 1280 (centered both ways)
# ---------------------------------------------------------------------------


def test_chat_column_wide_vs_base(
    browser: Browser, app_url: str, db_ready: None
) -> None:
    """The chat page's .chat-shell doubles at the 1500px breakpoint:
    92rem (1472px, ±4px) at 1920×1080, centered; 46rem (736px, ±4px)
    at 1280×800 — the base below the breakpoint."""
    wide = browser.new_page(viewport=WIDE_VIEWPORT)
    try:
        wide.goto(f"{app_url}/")
        wide.locator("#suggestions .suggestion-chip").first.wait_for(
            state="visible", timeout=10_000
        )
        _assert_width(wide, ".chat-shell", WIDE_PX, "chat @ 1920px")
        _assert_centered(wide, ".chat-shell", 1920, "chat @ 1920px")
    finally:
        wide.close()

    base = browser.new_page(viewport=BASE_VIEWPORT)
    try:
        base.goto(f"{app_url}/")
        base.locator("#suggestions .suggestion-chip").first.wait_for(
            state="visible", timeout=10_000
        )
        _assert_width(base, ".chat-shell", BASE_PX, "chat @ 1280px")
        _assert_centered(base, ".chat-shell", 1280, "chat @ 1280px")
    finally:
        base.close()


# ---------------------------------------------------------------------------
# 2. Document viewer: .doc-md (and its .doc-summary panel) at both
#    widths — the owner-expanded surface
# ---------------------------------------------------------------------------


def test_document_column_wide_vs_base(
    browser: Browser, app_url: str, mock_llm: int, db_ready: None
) -> None:
    """A seeded md document (with a summary) renders .doc-md at 1472px
    at 1920 and 736px at 1280 — and the adjacent .doc-summary panel
    matches the column at 1920 (.doc-summary:has(+ .doc-md))."""
    _reset_db(mock_llm, seed=True)
    _seed_summary_doc()

    wide = browser.new_page(viewport=WIDE_VIEWPORT)
    try:
        wide.goto(app_url + FIXTURE_DOC_URL)
        expect(wide.locator("#doc-title")).to_have_text(FIXTURE_TITLE, timeout=15_000)
        expect(wide.locator("#doc-content .doc-md")).to_be_visible(timeout=15_000)
        expect(
            wide.locator(".doc-summary:has(+ .doc-md)")
        ).to_have_count(1, timeout=15_000)
        _assert_width(wide, "#doc-content .doc-md", WIDE_PX, "document @ 1920px")
        _assert_width(
            wide, ".doc-summary:has(+ .doc-md)", WIDE_PX, "summary panel @ 1920px"
        )
    finally:
        wide.close()

    base = browser.new_page(viewport=BASE_VIEWPORT)
    try:
        base.goto(app_url + FIXTURE_DOC_URL)
        expect(base.locator("#doc-title")).to_have_text(FIXTURE_TITLE, timeout=15_000)
        expect(base.locator("#doc-content .doc-md")).to_be_visible(timeout=15_000)
        _assert_width(base, "#doc-content .doc-md", BASE_PX, "document @ 1280px")
    finally:
        base.close()


# ---------------------------------------------------------------------------
# 3. Shared page: .shared-shell at 1472px for a guest at 1920
# ---------------------------------------------------------------------------


def test_shared_column_wide(
    page: Page,
    browser: Browser,
    app_url: str,
    mock_llm: int,
    db_ready: None,
) -> None:
    """A real auto-saved conversation, shared by token, renders its
    .shared-shell at 1472px (±4px) at 1920 in a FRESH anonymous
    context (no cookies — the guest's only credential is the token)."""
    _reset_db(mock_llm, seed=True)
    page.set_default_timeout(30_000)

    login(page, app_url, next="/")
    expect(page).to_have_url(app_url + "/", timeout=30_000)

    q = "How is my Kubernetes cluster set up? (wide-column)"
    _ask(page, q)

    cookies = _admin_cookies(page)
    row = _wait_saved_row(app_url, cookies, _auto_title(q))
    chat_id: str = row["id"]
    anon_ctx = None
    try:
        # Public since phase 55 — the share endpoint takes no session.
        r = httpx.post(f"{app_url}/api/chats/{chat_id}/share", timeout=10)
        assert r.status_code == 200
        share_url = r.json()["share_url"]
        assert SHARE_URL_RE.fullmatch(share_url), f"bad share_url shape: {share_url}"

        anon_ctx = browser.new_context(viewport=WIDE_VIEWPORT)
        anon = anon_ctx.new_page()
        anon.set_default_timeout(30_000)
        anon.goto(app_url + share_url)
        expect(anon.locator("#shared-title")).to_have_text(
            _auto_title(q), timeout=15_000
        )
        expect(anon.locator(".msg.brain .bubble")).to_contain_text(
            MOCK_ANSWER_MARKER, timeout=30_000
        )
        _assert_width(anon, ".shared-shell", WIDE_PX, "shared @ 1920px")
        _assert_centered(anon, ".shared-shell", 1920, "shared @ 1920px")
    finally:
        if anon_ctx is not None:
            anon_ctx.close()
        _delete_chat(app_url, cookies, chat_id)


# ---------------------------------------------------------------------------
# 4. Below the breakpoint: 360px and 900px are byte-for-byte the old
#    rules — no overflow, no leaked wide column
# ---------------------------------------------------------------------------


def test_narrow_unchanged(
    browser: Browser, app_url: str, db_ready: None
) -> None:
    """The min-width:1500px override must not leak below the
    breakpoint: at 360px no horizontal overflow and the shell is the
    existing mobile rule — full-bleed at the viewport width (the shell
    IS its .container, so the 0.9rem mobile gutters sit in its own
    padding, inside the measured box); at 900px the shell holds the
    46rem base (736px — a leaked 92rem rule would pin it to the 860px
    content box instead, so 736px is the discriminator)."""
    phone = browser.new_page(viewport={"width": 360, "height": 740})
    try:
        phone.goto(f"{app_url}/")
        phone.locator("#suggestions .suggestion-chip").first.wait_for(
            state="visible", timeout=10_000
        )
        _assert_no_doc_overflow(phone, "chat @ 360px")
        _assert_width(phone, ".chat-shell", 360, "chat @ 360px")
    finally:
        phone.close()

    tablet = browser.new_page(viewport={"width": 900, "height": 800})
    try:
        tablet.goto(f"{app_url}/")
        tablet.locator("#suggestions .suggestion-chip").first.wait_for(
            state="visible", timeout=10_000
        )
        _assert_no_doc_overflow(tablet, "chat @ 900px")
        _assert_width(tablet, ".chat-shell", BASE_PX, "chat @ 900px")
        _assert_centered(tablet, ".chat-shell", 900, "chat @ 900px")
    finally:
        tablet.close()