Blame for tasks/imdb/tests/oracle-runtime/clone/backend/db.py

"""SQLite persistence layer for the IMDb offline clone persistent backend.

Owns the durable, server-side state: frozen titles, people and credits,
the home carousel capture rows, the two synthetic fixture accounts,
watchlist entries, ratings, and custom lists.

Contract highlights:
- WAL journal mode, foreign keys ON, busy timeout for reload robustness.
- Ordered migrations tracked in schema_migrations (legacy -> head safe).
- Seeded rows are dated facts frozen at the 2026-07-25 capture; local
  mutations never touch the seeded aggregate columns.
- The database file lives under WEBSITEBENCH_DATA_DIR (with the historical
  compatibility alias still accepted; default
  materials/imdb/data), always outside the candidate clone/ tree.

Aggregate-rating policy (applied generically to every title): the displayed
IMDb aggregate and its source vote count are immutable dated seeds. A local
user rating is stored and displayed separately and never modifies or
impersonates the IMDb aggregate.

Optimistic concurrency note: titles are immutable in this fixture and
watchlist reordering is not a captured source behavior, so there is no
user-editable versioned resource; stale-version conflict handling is
honestly N/A rather than simulated.
"""

from __future__ import annotations

import json
import sqlite3
from collections.abc import Iterable

from . import ASSETS_BASE, CATALOG_ASSETS_BASE, FROZEN_CLOCK, SITE_ID, db_path
from .catalog import (
    PERSON_CREDITS,
    complete_catalog_titles,
    extra_people,
    extra_titles,
)

FOREIGN_LIST_ID = "ls-510448718"

# ---------------------------------------------------------------------------
# Frozen seed data (dated facts captured 2026-07-25; never mutated locally)
# ---------------------------------------------------------------------------

SEED_ACCOUNTS = (
    ("alex", "ur-alex-green", "Alex Green"),
    ("jordan", "ur-jordan-lee", "Jordan Lee"),
)

SEED_TITLES = (
    {
        "id": "tt0468569",
        "title": "The Dark Knight",
        "year": "2008",
        "cert": "PG-13",
        "runtime": "2h 32m",
        "imdb_rating": "9.1",
        "votes": "3.2M",
        "metascore": "85",
        "popularity": "31",
        "watchlist_count": "4.2M",
        "top_rank": "Top rated movie #3",
        "plot": (
            "When a menace known as the Joker wreaks havoc and chaos on the "
            "people of Gotham, Batman, James Gordon and Harvey Dent must "
            "work together to put an end to the madness."
        ),
        "director": "Christopher Nolan",
        "writers": "Jonathan Nolan, Christopher Nolan, David S. Goyer",
        "stars": "Christian Bale, Heath Ledger, Aaron Eckhart",
        "genres": [
            "DC", "Action Epic", "Epic", "Psychological Drama",
            "Psychological Thriller", "Superhero", "Crime", "Thriller",
        ],
        "poster": f"{ASSETS_BASE}/title-dark-knight/poster-tt0468569-main-380x562.jpg",
        "card": f"{ASSETS_BASE}/watchlist-page/poster-tt0468569-280x414.jpg",
    },
    {
        "id": "tt0816692",
        "title": "Interstellar",
        "year": "2014",
        "cert": "PG-13",
        "runtime": "2h 49m",
        "imdb_rating": "8.7",
        "votes": "2.6M",
        "metascore": "74",
        "popularity": "15",
        "watchlist_count": "4.4M",
        "top_rank": "Top rated movie #17",
        "plot": (
            "In a dystopian future where Earth has become near-uninhabitable, "
            "a team of astronauts embark on a mission to find a new home for "
            "humanity."
        ),
        "director": "Christopher Nolan",
        "writers": "Jonathan Nolan, Christopher Nolan",
        "stars": "Matthew McConaughey, Anne Hathaway, Jessica Chastain",
        "genres": [
            "Adventure Epic", "Epic", "Psychological Drama", "Quest",
            "Sci-Fi Epic", "Space Sci-Fi", "Time Travel", "Adventure",
            "Drama", "Sci-Fi",
        ],
        "poster": f"{ASSETS_BASE}/title-interstellar/poster-tt0816692-main-380x562.jpg",
        "card": f"{ASSETS_BASE}/watchlist-page/poster-tt0816692-280x414.jpg",
    },
    {
        "id": "tt0110912",
        "title": "Pulp Fiction",
        "year": "1994",
        "cert": "R",
        "runtime": "2h 34m",
        "imdb_rating": "8.8",
        "votes": "2.5M",
        "metascore": "95",
        "popularity": "130",
        "watchlist_count": "4.0M",
        "top_rank": "Top rated movie #9",
        "plot": (
            "The lives of two mob hitmen, a boxer, a gangster and his wife, "
            "and a pair of diner bandits intertwine in four tales of "
            "violence and redemption."
        ),
        "director": "Quentin Tarantino",
        "writers": "Quentin Tarantino, Roger Avary",
        "stars": "John Travolta, Uma Thurman, Samuel L. Jackson",
        "genres": ["Dark Comedy", "Drug Crime", "Gangster", "Crime", "Drama"],
        "poster": f"{ASSETS_BASE}/title-pulp-fiction/poster-tt0110912-main-380x562.jpg",
        "card": f"{ASSETS_BASE}/watchlist-page/poster-tt0110912-280x414.jpg",
    },
) + extra_titles(ASSETS_BASE)

# ``SEED_TITLES`` retains the historical 36-title focus identity.  The
# actionable directory is its exact union with the unchanged Top 250 and
# Popular 81 catalog contracts (302 additional IDs, 338 total).
ALL_TITLES = complete_catalog_titles(SEED_TITLES)

SEED_HOME_CAROUSEL = (
    # (kind, position, image, heading, caption, duration)
    (
        "hero", 1, f"{ASSETS_BASE}/home/home-hero-1-760x428.jpg",
        "\u201cLanterns\u201d",
        "Watch the Official Trailer From Comic-Con", "2:57",
    ),
    (
        "hero", 2, f"{ASSETS_BASE}/home/home-hero-2-760x428.jpg",
        "\u201cThe Lord of the Rings: The Rings of Power\u201d Season 3",
        "Watch the Comic-Con Teaser", "1:38",
    ),
    (
        "hero", 3, f"{ASSETS_BASE}/home/home-hero-3-760x428.jpg",
        "Get Into 'The Odyssey' Craziness With Christopher Nolan "
        "and the Cast",
        "Watch Our Interview", "9:23",
    ),
    (
        "hero", 4, f"{ASSETS_BASE}/home/home-hero-4-760x428.jpg",
        "Eddie Marsan Is 'Clayface'",
        "Watch the Trailer", "2:29",
    ),
    ("fanpick", 1, f"{ASSETS_BASE}/home/home-fanpick-1-280x414.jpg", "", "", ""),
    ("fanpick", 2, f"{ASSETS_BASE}/home/home-fanpick-2-280x414.jpg", "", "", ""),
    ("fanpick", 3, f"{ASSETS_BASE}/home/home-fanpick-3-280x414.jpg", "", "", ""),
    ("fanpick", 4, f"{ASSETS_BASE}/home/home-fanpick-4-280x414.jpg", "", "", ""),
)

SEED_FIXTURE_LISTS = (
    # Jordan pre-owns a private list so foreign-owner 403 paths are testable.
    (FOREIGN_LIST_ID, "jordan", "Jordan's Noir Classics", "Titles", "Private"),
)

# Exact seeded aggregate ballots behind the captured one-decimal displays.
# (title_id, seed_vote_count, seed_rating_avg). Realistic multi-million
# counts mean a single local vote shifts the display negligibly but
# deterministically -- the generic rule for every title row.
SEED_TITLE_AGGREGATES = (
    ("tt0468569", 3_248_112, 9.1),
    ("tt0816692", 2_637_845, 8.7),
    ("tt0110912", 2_524_930, 8.8),
) + tuple(
    (title["id"], title["seed_vote_count"], title["seed_rating_avg"])
    for title in SEED_TITLES[3:]
)

ALL_TITLE_AGGREGATES = SEED_TITLE_AGGREGATES + tuple(
    (title["id"], title["seed_vote_count"], title["seed_rating_avg"])
    for title in ALL_TITLES
    if title["id"] not in {item[0] for item in SEED_TITLE_AGGREGATES}
    and title.get("seed_vote_count") is not None
    and title.get("seed_rating_avg") is not None
)

SEED_PEOPLE = (
    # (id, name, roles, known_for, thumb, match_terms)
    (
        "nm0000384",
        "Danny Elfman",
        "Music Department, Composer, Actor",
        "The Nightmare Before Christmas (1993)",
        f"{CATALOG_ASSETS_BASE}/catalog-people/nm0000384.svg",
        ["dark knight"],
    ),
) + extra_people(ASSETS_BASE)

SEED_SEARCH_CATALOG = (
    # (rank, display_title, local_title_id, year, runtime, cert, metascore,
    #  rating, votes, thumb, match_terms)
    # Ratings/votes for locally captured titles are computed live from the
    # aggregate ballots; the static columns hold the frozen capture values
    # for rows whose full title pages were not captured.
    (
        10, "The Dark Knight", "tt0468569", "2008", "2h 32m", "PG-13",
        "85", "9.1", "3.2M",
        f"{ASSETS_BASE}/find-search/search-thumb-tt0468569-180x266.jpg",
        [],
    ),
    (
        20, "The Dark Knight Rises", None, "2012", "2h 44m", "PG-13",
        "78", "8.4", "2M",
        f"{ASSETS_BASE}/find-search/search-thumb-dark-knight-rises-180x266.jpg",
        [],
    ),
    (
        30, "Citizen Vigilante", None, "2026", "1h 29m", "Not Rated",
        None, "5.9", "33K",
        f"{ASSETS_BASE}/find-search/search-thumb-result-3-180x266.jpg",
        ["dark knight"],
    ),
    (
        40, "Batman: The Dark Knight Returns, Part 2", None, "2013",
        "1h 16m", "PG-13", None, "8.3", "62K",
        f"{ASSETS_BASE}/find-search/search-thumb-result-4-180x266.jpg",
        [],
    ),
    (
        50, "Batman: The Dark Knight Returns, Part 1", None, "2012",
        "1h 16m", "PG-13", None, "7.9", "68K",
        f"{ASSETS_BASE}/find-search/search-thumb-result-5-180x266.jpg",
        [],
    ),
    (
        60, "Interstellar", "tt0816692", "2014", "2h 49m", "PG-13",
        "74", "8.7", "2.6M",
        f"{ASSETS_BASE}/watchlist-page/poster-tt0816692-280x414.jpg",
        [],
    ),
    (
        70, "Pulp Fiction", "tt0110912", "1994", "2h 34m", "R",
        "95", "8.8", "2.5M",
        f"{ASSETS_BASE}/watchlist-page/poster-tt0110912-280x414.jpg",
        [],
    ),
)

SEED_HOME_TITLE_RAILS = (
    # (rail, position, title_id)
    ("fan-favorites", 1, "tt0816692"),
    ("fan-favorites", 2, "tt0110912"),
)

# ---------------------------------------------------------------------------
# Migrations (ordered; tracked in schema_migrations)
# ---------------------------------------------------------------------------

MIGRATIONS: tuple[tuple[str, str], ...] = (
    (
        "0001-initial-schema",
        """
        CREATE TABLE accounts (
            key TEXT PRIMARY KEY,
            public_id TEXT NOT NULL UNIQUE,
            display_name TEXT NOT NULL
        );
        CREATE TABLE titles (
            id TEXT PRIMARY KEY,
            title TEXT NOT NULL,
            year TEXT NOT NULL,
            cert TEXT NOT NULL,
            runtime TEXT NOT NULL,
            imdb_rating TEXT NOT NULL,
            votes TEXT NOT NULL,
            metascore TEXT NOT NULL,
            popularity TEXT NOT NULL,
            watchlist_count TEXT NOT NULL,
            top_rank TEXT NOT NULL,
            plot TEXT NOT NULL,
            director TEXT NOT NULL,
            writers TEXT NOT NULL,
            stars TEXT NOT NULL,
            genres_json TEXT NOT NULL,
            poster TEXT NOT NULL,
            card TEXT NOT NULL
        );
        CREATE TABLE home_carousel (
            kind TEXT NOT NULL,
            position INTEGER NOT NULL,
            image TEXT NOT NULL,
            heading TEXT NOT NULL,
            caption TEXT NOT NULL,
            duration TEXT NOT NULL,
            PRIMARY KEY (kind, position)
        );
        CREATE TABLE watchlist_entries (
            account_key TEXT NOT NULL REFERENCES accounts(key),
            title_id TEXT NOT NULL REFERENCES titles(id),
            PRIMARY KEY (account_key, title_id)
        );
        CREATE TABLE ratings (
            account_key TEXT NOT NULL REFERENCES accounts(key),
            title_id TEXT NOT NULL REFERENCES titles(id),
            value INTEGER NOT NULL CHECK (value BETWEEN 1 AND 10),
            PRIMARY KEY (account_key, title_id)
        );
        CREATE TABLE lists (
            id TEXT PRIMARY KEY,
            owner_key TEXT NOT NULL REFERENCES accounts(key),
            name TEXT NOT NULL,
            list_type TEXT NOT NULL,
            privacy TEXT NOT NULL
        );
        CREATE TABLE list_members (
            list_id TEXT NOT NULL REFERENCES lists(id) ON DELETE CASCADE,
            title_id TEXT NOT NULL REFERENCES titles(id),
            PRIMARY KEY (list_id, title_id)
        );
        """,
    ),
    (
        "0002-frozen-clock-audit-columns",
        f"""
        ALTER TABLE watchlist_entries
            ADD COLUMN added_at TEXT NOT NULL DEFAULT '{FROZEN_CLOCK}';
        ALTER TABLE ratings
            ADD COLUMN updated_at TEXT NOT NULL DEFAULT '{FROZEN_CLOCK}';
        ALTER TABLE lists
            ADD COLUMN created_at TEXT NOT NULL DEFAULT '{FROZEN_CLOCK}';
        """,
    ),
    (
        "0003-catalog-aggregates-people-search",
        """
        CREATE TABLE title_aggregates (
            title_id TEXT PRIMARY KEY REFERENCES titles(id),
            seed_vote_count INTEGER NOT NULL CHECK (seed_vote_count > 0),
            seed_rating_avg REAL NOT NULL
                CHECK (seed_rating_avg BETWEEN 1.0 AND 10.0)
        );
        CREATE TABLE people (
            id TEXT PRIMARY KEY,
            name TEXT NOT NULL,
            roles TEXT NOT NULL,
            known_for TEXT NOT NULL,
            thumb TEXT NOT NULL,
            match_terms_json TEXT NOT NULL
        );
        CREATE TABLE search_catalog (
            rank INTEGER PRIMARY KEY,
            display_title TEXT NOT NULL,
            local_title_id TEXT REFERENCES titles(id),
            year TEXT NOT NULL,
            runtime TEXT NOT NULL,
            cert TEXT NOT NULL,
            metascore TEXT,
            rating TEXT NOT NULL,
            votes TEXT NOT NULL,
            thumb TEXT NOT NULL,
            match_terms_json TEXT NOT NULL
        );
        CREATE TABLE home_title_rails (
            rail TEXT NOT NULL,
            position INTEGER NOT NULL,
            title_id TEXT NOT NULL REFERENCES titles(id),
            PRIMARY KEY (rail, position)
        );
        """,
    ),
)

HEAD_VERSION = MIGRATIONS[-1][0]

# WebsiteBench owns this additive site schema through the runtime-declared
# migration hook.  The historical three-version migration ledger remains
# intact for tasks 901–905 compatibility; new entities have their own current
# site migration identity.
SITE_SCHEMA_VERSION = "0001-directory-reviews-lists"
SITE_SCHEMA_SQL = """
CREATE TABLE IF NOT EXISTS websitebench_imdb_migrations (
    version TEXT PRIMARY KEY,
    applied_at TEXT NOT NULL
);
CREATE TABLE IF NOT EXISTS title_details (
    title_id TEXT PRIMARY KEY REFERENCES titles(id) ON DELETE CASCADE,
    title_type TEXT NOT NULL CHECK (title_type IN ('movie','series','episode')),
    series_id TEXT REFERENCES titles(id),
    season_number INTEGER,
    episode_number INTEGER,
    asset_group TEXT NOT NULL,
    catalog_credit TEXT NOT NULL DEFAULT ''
);
CREATE TABLE IF NOT EXISTS credits (
    title_id TEXT NOT NULL REFERENCES titles(id) ON DELETE CASCADE,
    person_id TEXT NOT NULL REFERENCES people(id) ON DELETE CASCADE,
    category TEXT NOT NULL,
    character_name TEXT NOT NULL DEFAULT '',
    position INTEGER NOT NULL DEFAULT 0,
    PRIMARY KEY (title_id, person_id, category, character_name)
);
CREATE TABLE IF NOT EXISTS media (
    id TEXT PRIMARY KEY,
    title_id TEXT NOT NULL REFERENCES titles(id) ON DELETE CASCADE,
    media_type TEXT NOT NULL CHECK (media_type IN ('image','video')),
    local_path TEXT NOT NULL,
    caption TEXT NOT NULL,
    position INTEGER NOT NULL,
    UNIQUE (title_id, media_type, position)
);
CREATE TABLE IF NOT EXISTS reviews (
    id INTEGER PRIMARY KEY AUTOINCREMENT,
    account_key TEXT NOT NULL REFERENCES accounts(key) ON DELETE CASCADE,
    title_id TEXT NOT NULL REFERENCES titles(id) ON DELETE CASCADE,
    summary TEXT NOT NULL,
    body TEXT NOT NULL,
    spoiler INTEGER NOT NULL DEFAULT 0 CHECK (spoiler IN (0,1)),
    created_at TEXT NOT NULL,
    updated_at TEXT NOT NULL,
    UNIQUE (account_key, title_id)
);
CREATE TABLE IF NOT EXISTS list_profiles (
    list_id TEXT PRIMARY KEY REFERENCES lists(id) ON DELETE CASCADE,
    description TEXT NOT NULL DEFAULT '',
    updated_at TEXT NOT NULL
);
CREATE INDEX IF NOT EXISTS reviews_title_idx
    ON reviews(title_id, updated_at DESC, id DESC);
CREATE INDEX IF NOT EXISTS credits_person_idx
    ON credits(person_id, position, title_id);
CREATE UNIQUE INDEX IF NOT EXISTS lists_owner_name_ci
    ON lists(owner_key, name COLLATE NOCASE);
"""


def connect() -> sqlite3.Connection:
    """Open the fixture database with WAL and foreign keys enabled."""
    path = db_path()
    path.parent.mkdir(parents=True, exist_ok=True)
    conn = sqlite3.connect(path, timeout=10, isolation_level=None)
    conn.row_factory = sqlite3.Row
    conn.execute("PRAGMA journal_mode=WAL")
    conn.execute("PRAGMA foreign_keys=ON")
    conn.execute("PRAGMA busy_timeout=10000")
    return conn


def applied_versions(conn: sqlite3.Connection) -> list[str]:
    conn.execute(
        """
        CREATE TABLE IF NOT EXISTS schema_migrations (
            version TEXT PRIMARY KEY,
            applied_at TEXT NOT NULL
        )
        """
    )
    rows = conn.execute(
        "SELECT version FROM schema_migrations ORDER BY version"
    ).fetchall()
    return [row["version"] for row in rows]


def apply_migrations(
    conn: sqlite3.Connection, upto: str | None = None
) -> list[str]:
    """Apply pending migrations in order; return newly applied versions.

    Each migration runs atomically: statements are executed one by one
    inside an explicit transaction (sqlite3.executescript would issue an
    implicit COMMIT, breaking atomicity), and the version row is recorded
    in the same transaction.
    """
    done = set(applied_versions(conn))
    applied: list[str] = []
    for version, script in MIGRATIONS:
        if version not in done:
            nested = conn.in_transaction
            if nested:
                conn.execute("SAVEPOINT imdb_schema_migration")
            else:
                conn.execute("BEGIN")
            try:
                for statement in script.split(";"):
                    if statement.strip():
                        conn.execute(statement)
                conn.execute(
                    "INSERT INTO schema_migrations (version, applied_at) "
                    "VALUES (?, ?)",
                    (version, FROZEN_CLOCK),
                )
                conn.execute(
                    "RELEASE SAVEPOINT imdb_schema_migration"
                    if nested else "COMMIT"
                )
            except sqlite3.Error:
                if nested:
                    conn.execute("ROLLBACK TO SAVEPOINT imdb_schema_migration")
                    conn.execute("RELEASE SAVEPOINT imdb_schema_migration")
                else:
                    conn.execute("ROLLBACK")
                raise
            applied.append(version)
        if upto is not None and version == upto:
            break
    migration_count = int(
        conn.execute("SELECT COUNT(*) FROM schema_migrations").fetchone()[0]
    )
    conn.execute(f"PRAGMA user_version = {migration_count}")
    return applied


def apply_site_backend_migrations(conn: sqlite3.Connection) -> None:
    """Runtime-declared, idempotent IMDb business migration hook."""

    apply_migrations(conn)
    conn.executescript(SITE_SCHEMA_SQL) if not conn.in_transaction else _execute_sql(
        conn, SITE_SCHEMA_SQL
    )
    _ensure_site_schema_columns(conn)
    conn.execute(
        "INSERT OR IGNORE INTO websitebench_imdb_migrations(version, applied_at) "
        "VALUES (?, ?)",
        (SITE_SCHEMA_VERSION, FROZEN_CLOCK),
    )
    seed_fixtures(conn)


def seed_site_backend(conn: sqlite3.Connection) -> None:
    """Runtime-declared seed hook for a newly bound site database."""

    seed_fixtures(conn)


def _ensure_site_schema_columns(conn: sqlite3.Connection) -> None:
    """Apply additive columns to databases created by earlier site revisions."""

    columns = {
        row["name"] for row in conn.execute("PRAGMA table_info(title_details)")
    }
    if "catalog_credit" not in columns:
        conn.execute(
            "ALTER TABLE title_details "
            "ADD COLUMN catalog_credit TEXT NOT NULL DEFAULT ''"
        )


def _execute_sql(conn: sqlite3.Connection, script: str) -> None:
    """Execute a simple schema script without stealing an outer transaction."""

    for statement in script.split(";"):
        if statement.strip():
            conn.execute(statement)


def seed_fixtures(conn: sqlite3.Connection) -> None:
    """Reconcile immutable catalog seeds without overwriting user state."""
    nested = conn.in_transaction
    if nested:
        conn.execute("SAVEPOINT imdb_seed")
    else:
        conn.execute("BEGIN")
    try:
        for key, public_id, display_name in SEED_ACCOUNTS:
            conn.execute(
                "INSERT OR IGNORE INTO accounts "
                "(key, public_id, display_name) VALUES (?, ?, ?)",
                (key, public_id, display_name),
            )
        for title in ALL_TITLES:
            conn.execute(
                """
                INSERT INTO titles (
                    id, title, year, cert, runtime, imdb_rating, votes,
                    metascore, popularity, watchlist_count, top_rank, plot,
                    director, writers, stars, genres_json, poster, card
                ) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)
                ON CONFLICT(id) DO UPDATE SET
                    title=excluded.title, year=excluded.year, cert=excluded.cert,
                    runtime=excluded.runtime, imdb_rating=excluded.imdb_rating,
                    votes=excluded.votes, metascore=excluded.metascore,
                    popularity=excluded.popularity,
                    watchlist_count=excluded.watchlist_count,
                    top_rank=excluded.top_rank, plot=excluded.plot,
                    director=excluded.director, writers=excluded.writers,
                    stars=excluded.stars, genres_json=excluded.genres_json,
                    poster=excluded.poster, card=excluded.card
                """,
                (
                    title["id"], title["title"], title["year"], title["cert"],
                    title["runtime"], title["imdb_rating"], title["votes"],
                    title["metascore"], title["popularity"],
                    title["watchlist_count"], title["top_rank"],
                    title["plot"], title["director"], title["writers"],
                    title["stars"], json.dumps(title["genres"]),
                    title["poster"], title["card"],
                ),
            )
        for kind, position, image, heading, caption, duration in (
            SEED_HOME_CAROUSEL
        ):
            conn.execute(
                "INSERT OR IGNORE INTO home_carousel "
                "(kind, position, image, heading, caption, duration) "
                "VALUES (?, ?, ?, ?, ?, ?)",
                (kind, position, image, heading, caption, duration),
            )
        for list_id, owner_key, name, list_type, privacy in SEED_FIXTURE_LISTS:
            conn.execute(
                "INSERT OR IGNORE INTO lists "
                "(id, owner_key, name, list_type, privacy, created_at) "
                "VALUES (?, ?, ?, ?, ?, ?)",
                (list_id, owner_key, name, list_type, privacy, FROZEN_CLOCK),
            )
        for title_id, seed_votes, seed_avg in ALL_TITLE_AGGREGATES:
            conn.execute(
                "INSERT INTO title_aggregates "
                "(title_id, seed_vote_count, seed_rating_avg) "
                "VALUES (?, ?, ?) ON CONFLICT(title_id) DO UPDATE SET "
                "seed_vote_count=excluded.seed_vote_count, "
                "seed_rating_avg=excluded.seed_rating_avg",
                (title_id, seed_votes, seed_avg),
            )
        # Credits and people are immutable directory rows. Reconcile them on
        # every seed so an upgraded persistent database converges to the same
        # exact 20-person catalog without touching any user-owned entity.
        conn.execute("DELETE FROM credits")
        person_ids = [person[0] for person in SEED_PEOPLE]
        placeholders = ",".join("?" for _ in person_ids)
        conn.execute(
            f"DELETE FROM people WHERE id NOT IN ({placeholders})", person_ids
        )
        for person_id, name, roles, known_for, thumb, terms in SEED_PEOPLE:
            conn.execute(
                "INSERT INTO people "
                "(id, name, roles, known_for, thumb, match_terms_json) "
                "VALUES (?, ?, ?, ?, ?, ?) ON CONFLICT(id) DO UPDATE SET "
                "name=excluded.name, roles=excluded.roles, "
                "known_for=excluded.known_for, thumb=excluded.thumb, "
                "match_terms_json=excluded.match_terms_json",
                (person_id, name, roles, known_for, thumb, json.dumps(terms)),
            )
        for index, title in enumerate(ALL_TITLES[3:], start=1):
            conn.execute(
                "INSERT INTO search_catalog ("
                "rank, display_title, local_title_id, year, runtime, cert, "
                "metascore, rating, votes, thumb, match_terms_json"
                ") VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?) "
                "ON CONFLICT(rank) DO UPDATE SET "
                "display_title=excluded.display_title, "
                "local_title_id=excluded.local_title_id, year=excluded.year, "
                "runtime=excluded.runtime, cert=excluded.cert, "
                "metascore=excluded.metascore, rating=excluded.rating, "
                "votes=excluded.votes, thumb=excluded.thumb, "
                "match_terms_json=excluded.match_terms_json",
                (
                    1000 + index,
                    title["title"],
                    title["id"],
                    title["year"],
                    title["runtime"],
                    title["cert"],
                    title["metascore"],
                    title["imdb_rating"],
                    (
                        _format_count(int(title["seed_vote_count"]))
                        if title.get("seed_vote_count") is not None
                        else "No ratings"
                    ),
                    title["card"],
                    json.dumps([title["director"], *title["genres"]]),
                ),
            )
        for (
            rank, display_title, local_title_id, year, runtime, cert,
            metascore, rating, votes, thumb, terms,
        ) in SEED_SEARCH_CATALOG:
            conn.execute(
                """
                INSERT INTO search_catalog (
                    rank, display_title, local_title_id, year, runtime,
                    cert, metascore, rating, votes, thumb, match_terms_json
                ) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)
                ON CONFLICT(rank) DO UPDATE SET
                    display_title=excluded.display_title,
                    local_title_id=excluded.local_title_id, year=excluded.year,
                    runtime=excluded.runtime, cert=excluded.cert,
                    metascore=excluded.metascore, rating=excluded.rating,
                    votes=excluded.votes, thumb=excluded.thumb,
                    match_terms_json=excluded.match_terms_json
                """,
                (
                    rank, display_title, local_title_id, year, runtime,
                    cert, metascore, rating, votes, thumb, json.dumps(terms),
                ),
            )
        for rail, position, title_id in SEED_HOME_TITLE_RAILS:
            conn.execute(
                "INSERT OR IGNORE INTO home_title_rails "
                "(rail, position, title_id) VALUES (?, ?, ?)",
                (rail, position, title_id),
            )
        detail_defaults = {
            "tt0468569": "title-dark-knight",
            "tt0816692": "title-interstellar",
            "tt0110912": "title-pulp-fiction",
        }
        for title in ALL_TITLES:
            title_type = title.get("title_type", "movie")
            conn.execute(
                "INSERT INTO title_details ("
                "title_id, title_type, series_id, season_number, "
                "episode_number, asset_group, catalog_credit) "
                "VALUES (?, ?, ?, ?, ?, ?, ?) "
                "ON CONFLICT(title_id) DO UPDATE SET "
                "title_type=excluded.title_type, series_id=excluded.series_id, "
                "season_number=excluded.season_number, "
                "episode_number=excluded.episode_number, "
                "asset_group=excluded.asset_group, "
                "catalog_credit=excluded.catalog_credit",
                (
                    title["id"],
                    title_type,
                    title.get("series_id"),
                    title.get("season_number"),
                    title.get("episode_number"),
                    title.get("asset_group") or detail_defaults[title["id"]],
                    title.get("catalog_credit", ""),
                ),
            )
            conn.execute(
                "INSERT INTO media ("
                "id, title_id, media_type, local_path, caption, position"
                ") VALUES (?, ?, 'image', ?, ?, 1) "
                "ON CONFLICT(id) DO UPDATE SET "
                "local_path=excluded.local_path, caption=excluded.caption, "
                "position=excluded.position",
                (
                    f"media-{title['id']}-poster",
                    title["id"],
                    title["poster"],
                    f"{title['title']} poster",
                ),
            )
        for position, (title_id, person_id, category, character) in enumerate(
            PERSON_CREDITS, start=1
        ):
            conn.execute(
                "INSERT OR IGNORE INTO credits ("
                "title_id, person_id, category, character_name, position"
                ") VALUES (?, ?, ?, ?, ?)",
                (title_id, person_id, category, character, position),
            )
        for list_id, *_ in SEED_FIXTURE_LISTS:
            conn.execute(
                "INSERT OR IGNORE INTO list_profiles "
                "(list_id, description, updated_at) VALUES (?, '', ?)",
                (list_id, FROZEN_CLOCK),
            )
        conn.execute("RELEASE SAVEPOINT imdb_seed" if nested else "COMMIT")
    except sqlite3.Error:
        if nested:
            conn.execute("ROLLBACK TO SAVEPOINT imdb_seed")
            conn.execute("RELEASE SAVEPOINT imdb_seed")
        elif conn.in_transaction:
            conn.execute("ROLLBACK")
        raise


def ensure_database() -> None:
    """Create/migrate/seed the database. Safe to call on every startup."""
    conn = connect()
    try:
        # Historical direct-db test helpers predate the runtime seam. Bind the
        # same site identity before they create business tables so the next
        # canonical SiteBackend.open() still fails closed for foreign data.
        conn.execute(
            "CREATE TABLE IF NOT EXISTS websitebench_site_binding ("
            "singleton INTEGER PRIMARY KEY CHECK (singleton=1), "
            "site_id TEXT NOT NULL UNIQUE, bound_at TEXT NOT NULL)"
        )
        conn.execute(
            "INSERT OR IGNORE INTO websitebench_site_binding"
            "(singleton,site_id,bound_at) VALUES (1,?,?)",
            (SITE_ID, FROZEN_CLOCK),
        )
        apply_migrations(conn)
        _execute_sql(conn, SITE_SCHEMA_SQL)
        _ensure_site_schema_columns(conn)
        conn.execute(
            "INSERT OR IGNORE INTO websitebench_imdb_migrations"
            "(version, applied_at) VALUES (?, ?)",
            (SITE_SCHEMA_VERSION, FROZEN_CLOCK),
        )
        seed_fixtures(conn)
    finally:
        conn.close()


def reset_database() -> dict[str, int]:
    """Wipe all site-local auth and business state, then re-seed fixtures."""
    ensure_database()
    conn = connect()
    try:
        conn.execute("BEGIN IMMEDIATE")
        removed = {
            "watchlist_entries": conn.execute(
                "DELETE FROM watchlist_entries"
            ).rowcount,
            "ratings": conn.execute("DELETE FROM ratings").rowcount,
            "list_members": conn.execute("DELETE FROM list_members").rowcount,
            "lists": conn.execute("DELETE FROM lists").rowcount,
            "reviews": conn.execute("DELETE FROM reviews").rowcount,
        }
        # Fixture reset is a reproducibility boundary, not merely a row wipe.
        # Review edit/delete routes carry the local integer id, so reset the
        # SQLite allocator as well and keep replay ids deterministic.
        conn.execute("DELETE FROM sqlite_sequence WHERE name = 'reviews'")
        auth_tables = (
            "local_auth_mail_outbox",
            "local_auth_password_reset_flows",
            "local_auth_registration_flows",
            "local_auth_mail_rate_limits",
            "local_auth_sessions",
            "local_auth_accounts",
        )
        existing = {
            row["name"]
            for row in conn.execute(
                "SELECT name FROM sqlite_master WHERE type='table'"
            ).fetchall()
        }
        for table in auth_tables:
            if table in existing:
                removed[table] = conn.execute(f"DELETE FROM {table}").rowcount
        conn.execute("COMMIT")
        seed_fixtures(conn)
        return removed
    finally:
        conn.close()


# ---------------------------------------------------------------------------
# Read helpers
# ---------------------------------------------------------------------------

def _format_count(count: int) -> str:
    """Format an exact ballot count the way the source site abbreviates it."""
    if count >= 1_000_000:
        text = f"{count / 1_000_000:.1f}"
        if text.endswith(".0"):
            text = text[:-2]
        return f"{text}M"
    if count >= 10_000:
        return f"{count // 1_000}K"
    if count >= 1_000:
        text = f"{count / 1_000:.1f}"
        if text.endswith(".0"):
            text = text[:-2]
        return f"{text}K"
    return str(count)


def title_aggregate(conn: sqlite3.Connection, title_id: str) -> dict | None:
    """Return the immutable captured aggregate plus separate local counts.

    A local rating is user-owned benchmark state and never changes or
    impersonates an IMDb aggregate. ``vote_count`` remains a historical
    diagnostic count for tasks 901–905; UI fields ``rating`` and ``votes``
    are derived exclusively from the frozen source seed.
    """
    seed = conn.execute(
        "SELECT seed_vote_count, seed_rating_avg FROM title_aggregates "
        "WHERE title_id = ?",
        (title_id,),
    ).fetchone()
    if seed is None:
        return None
    user = conn.execute(
        "SELECT COUNT(*) AS n "
        "FROM ratings WHERE title_id = ?",
        (title_id,),
    ).fetchone()
    source_vote_count = int(seed["seed_vote_count"])
    local_vote_count = int(user["n"])
    return {
        "rating": f"{float(seed['seed_rating_avg']):.1f}",
        "votes": _format_count(source_vote_count),
        "source_vote_count": source_vote_count,
        "local_vote_count": local_vote_count,
        "vote_count": source_vote_count + local_vote_count,
    }


def _title_dict(
    row: sqlite3.Row, conn: sqlite3.Connection | None = None
) -> dict:
    data = dict(row)
    data["genres"] = json.loads(data.pop("genres_json"))
    if conn is not None:
        aggregate = title_aggregate(conn, data["id"])
        if aggregate is not None:
            data["imdb_rating"] = aggregate["rating"]
            data["votes"] = aggregate["votes"]
        detail = conn.execute(
            "SELECT title_type, series_id, season_number, episode_number, "
            "asset_group, catalog_credit FROM title_details WHERE title_id = ?",
            (data["id"],),
        ).fetchone()
        if detail is not None:
            data.update(dict(detail))
            if data.get("series_id"):
                series = conn.execute(
                    "SELECT title FROM titles WHERE id=?", (data["series_id"],)
                ).fetchone()
                data["series_title"] = series["title"] if series else None
    return data


def account_by_key(conn: sqlite3.Connection, key: str) -> dict | None:
    row = conn.execute(
        "SELECT key, public_id, display_name FROM accounts WHERE key = ?",
        (key,),
    ).fetchone()
    if row is None:
        return None
    return {"key": row["key"], "id": row["public_id"], "name": row["display_name"]}


def create_registered_account(
    conn: sqlite3.Connection, registration: dict[str, str]
) -> str:
    """Create the business subject inside the auth registration transaction."""

    suffix = registration["account_id"].removeprefix("account_")[:24]
    key = f"member-{suffix}"
    conn.execute(
        "INSERT INTO accounts(key, public_id, display_name) VALUES (?, ?, ?)",
        (key, f"ur-{suffix}", registration["display_name"]),
    )
    return key


def all_accounts(conn: sqlite3.Connection) -> dict[str, dict]:
    rows = conn.execute(
        "SELECT key, public_id, display_name FROM accounts ORDER BY key"
    ).fetchall()
    return {
        row["key"]: {"id": row["public_id"], "name": row["display_name"]}
        for row in rows
    }


def get_title(conn: sqlite3.Connection, title_id: str) -> dict | None:
    row = conn.execute(
        "SELECT * FROM titles WHERE id = ?", (title_id,)
    ).fetchone()
    return _title_dict(row, conn) if row else None


def title_ids(conn: sqlite3.Connection) -> set[str]:
    return {
        row["id"] for row in conn.execute("SELECT id FROM titles").fetchall()
    }


def home_carousel(conn: sqlite3.Connection, kind: str) -> list[dict]:
    rows = conn.execute(
        "SELECT image, heading, caption, duration FROM home_carousel "
        "WHERE kind = ? ORDER BY position",
        (kind,),
    ).fetchall()
    return [dict(row) for row in rows]


def home_rail_titles(conn: sqlite3.Connection, rail: str) -> list[dict]:
    rows = conn.execute(
        """
        SELECT titles.* FROM home_title_rails
        JOIN titles ON titles.id = home_title_rails.title_id
        WHERE home_title_rails.rail = ?
        ORDER BY home_title_rails.position
        """,
        (rail,),
    ).fetchall()
    return [_title_dict(row, conn) for row in rows]


def all_titles(
    conn: sqlite3.Connection, *, title_type: str | None = None
) -> list[dict]:
    """Return the fixed local directory in title order."""

    if title_type is None:
        rows = conn.execute("SELECT * FROM titles ORDER BY title COLLATE NOCASE").fetchall()
    else:
        rows = conn.execute(
            "SELECT titles.* FROM titles JOIN title_details "
            "ON title_details.title_id=titles.id "
            "WHERE title_details.title_type=? ORDER BY titles.title COLLATE NOCASE",
            (title_type,),
        ).fetchall()
    return [_title_dict(row, conn) for row in rows]


def chart_titles(conn: sqlite3.Connection, chart: str) -> list[dict]:
    order = (
        "title_aggregates.seed_rating_avg DESC, "
        "title_aggregates.seed_vote_count DESC"
        if chart == "top"
        else "CAST(titles.popularity AS INTEGER), titles.title COLLATE NOCASE"
    )
    rows = conn.execute(
        "SELECT titles.* FROM titles JOIN title_details "
        "ON title_details.title_id=titles.id JOIN title_aggregates "
        "ON title_aggregates.title_id=titles.id "
        "WHERE title_details.title_type='movie' ORDER BY " + order
    ).fetchall()
    return [_title_dict(row, conn) for row in rows]


def get_person(conn: sqlite3.Connection, person_id: str) -> dict | None:
    row = conn.execute("SELECT * FROM people WHERE id=?", (person_id,)).fetchone()
    if row is None:
        return None
    result = dict(row)
    result["match_terms"] = json.loads(result.pop("match_terms_json"))
    result["credits"] = credits_for_person(conn, person_id)
    return result


def all_people(conn: sqlite3.Connection) -> list[dict]:
    """Return the complete fixed people directory in display-name order."""

    rows = conn.execute(
        "SELECT id FROM people ORDER BY name COLLATE NOCASE, id"
    ).fetchall()
    return [get_person(conn, row["id"]) for row in rows]


def credits_for_person(conn: sqlite3.Connection, person_id: str) -> list[dict]:
    rows = conn.execute(
        "SELECT credits.category, credits.character_name, titles.* "
        "FROM credits JOIN titles ON titles.id=credits.title_id "
        "WHERE credits.person_id=? ORDER BY credits.position, titles.year DESC",
        (person_id,),
    ).fetchall()
    results: list[dict] = []
    for row in rows:
        item = dict(row)
        category = item.pop("category")
        character = item.pop("character_name")
        title = item
        title["genres"] = json.loads(title.pop("genres_json"))
        title["category"] = category
        title["character_name"] = character
        results.append(title)
    return results


def credits_for_title(conn: sqlite3.Connection, title_id: str) -> list[dict]:
    rows = conn.execute(
        "SELECT people.id, people.name, people.roles, people.known_for, "
        "people.thumb, credits.category, credits.character_name "
        "FROM credits JOIN people ON people.id=credits.person_id "
        "WHERE credits.title_id=? ORDER BY credits.position, people.name",
        (title_id,),
    ).fetchall()
    return [dict(row) for row in rows]


def media_for_title(conn: sqlite3.Connection, title_id: str) -> list[dict]:
    rows = conn.execute(
        "SELECT id, media_type, local_path, caption, position FROM media "
        "WHERE title_id=? ORDER BY position, id",
        (title_id,),
    ).fetchall()
    return [dict(row) for row in rows]


# ---------------------------------------------------------------------------
# Search (DB-backed; matches against titles and captured search catalog)
# ---------------------------------------------------------------------------

def _matches(query_folded: str, candidates: Iterable[str]) -> bool:
    # A one-character title such as ``M`` must not match every query that
    # happens to contain that character. Search is query-within-field; aliases
    # are already represented as their own candidate fields.
    return any(term and query_folded in term for term in candidates)


def search_titles(conn: sqlite3.Connection, query: str) -> list[dict]:
    """Return search rows whose title (or captured match term) fits query."""
    folded = query.casefold().strip()
    if not folded:
        return []
    results: list[dict] = []
    for row in conn.execute(
        "SELECT * FROM search_catalog ORDER BY rank"
    ).fetchall():
        terms = [row["display_title"].casefold()]
        terms.extend(
            term.casefold()
            for term in json.loads(row["match_terms_json"])
        )
        if not _matches(folded, terms):
            continue
        rating = row["rating"]
        votes = row["votes"]
        if row["local_title_id"]:
            aggregate = title_aggregate(conn, row["local_title_id"])
            if aggregate is not None:
                rating = aggregate["rating"]
                votes = aggregate["votes"]
        results.append(
            {
                "title": row["display_title"],
                "local_id": row["local_title_id"],
                "year": row["year"],
                "runtime": row["runtime"],
                "cert": row["cert"],
                "metascore": row["metascore"],
                "rating": rating,
                "votes": votes,
                "thumb": row["thumb"],
            }
        )
    return results


def search_people(conn: sqlite3.Connection, query: str) -> list[dict]:
    folded = query.casefold().strip()
    if not folded:
        return []
    results: list[dict] = []
    for row in conn.execute("SELECT * FROM people ORDER BY id").fetchall():
        terms = [row["name"].casefold()]
        terms.extend(
            term.casefold()
            for term in json.loads(row["match_terms_json"])
        )
        if not _matches(folded, terms):
            continue
        results.append(
            {
                "id": row["id"],
                "name": row["name"],
                "roles": row["roles"],
                "known_for": row["known_for"],
                "thumb": row["thumb"],
            }
        )
    return results


# ---------------------------------------------------------------------------
# Watchlist (server-owned; idempotent per (account, title))
# ---------------------------------------------------------------------------

def watchlist_title_ids(conn: sqlite3.Connection, account_key: str) -> list[str]:
    rows = conn.execute(
        "SELECT title_id FROM watchlist_entries WHERE account_key = ? "
        "ORDER BY rowid",
        (account_key,),
    ).fetchall()
    return [row["title_id"] for row in rows]


def watchlist_titles(conn: sqlite3.Connection, account_key: str) -> list[dict]:
    rows = conn.execute(
        """
        SELECT titles.* FROM watchlist_entries
        JOIN titles ON titles.id = watchlist_entries.title_id
        WHERE watchlist_entries.account_key = ?
        ORDER BY watchlist_entries.rowid
        """,
        (account_key,),
    ).fetchall()
    return [_title_dict(row, conn) for row in rows]


def watchlist_add(
    conn: sqlite3.Connection, account_key: str, title_id: str
) -> str:
    """Idempotent add; returns 'added' or 'exists'."""
    cursor = conn.execute(
        "INSERT OR IGNORE INTO watchlist_entries "
        "(account_key, title_id, added_at) VALUES (?, ?, ?)",
        (account_key, title_id, FROZEN_CLOCK),
    )
    return "added" if cursor.rowcount else "exists"


def watchlist_remove(
    conn: sqlite3.Connection, account_key: str, title_id: str
) -> bool:
    cursor = conn.execute(
        "DELETE FROM watchlist_entries WHERE account_key = ? AND title_id = ?",
        (account_key, title_id),
    )
    return bool(cursor.rowcount)


# ---------------------------------------------------------------------------
# Ratings (1-10 integer; single row per account+title; deletable)
# ---------------------------------------------------------------------------

def get_rating(
    conn: sqlite3.Connection, account_key: str, title_id: str
) -> int | None:
    row = conn.execute(
        "SELECT value FROM ratings WHERE account_key = ? AND title_id = ?",
        (account_key, title_id),
    ).fetchone()
    return row["value"] if row else None


def ratings_for_account(
    conn: sqlite3.Connection, account_key: str
) -> dict[str, int]:
    rows = conn.execute(
        "SELECT title_id, value FROM ratings WHERE account_key = ?",
        (account_key,),
    ).fetchall()
    return {row["title_id"]: row["value"] for row in rows}


def set_rating(
    conn: sqlite3.Connection, account_key: str, title_id: str, value: int
) -> None:
    if not isinstance(value, int) or not 1 <= value <= 10:
        raise ValueError("rating must be an integer between 1 and 10")
    conn.execute(
        """
        INSERT INTO ratings (account_key, title_id, value, updated_at)
        VALUES (?, ?, ?, ?)
        ON CONFLICT (account_key, title_id)
        DO UPDATE SET value = excluded.value, updated_at = excluded.updated_at
        """,
        (account_key, title_id, value, FROZEN_CLOCK),
    )


def delete_rating(
    conn: sqlite3.Connection, account_key: str, title_id: str
) -> bool:
    cursor = conn.execute(
        "DELETE FROM ratings WHERE account_key = ? AND title_id = ?",
        (account_key, title_id),
    )
    return bool(cursor.rowcount)


# ---------------------------------------------------------------------------
# Custom lists (server-owned; membership idempotent; owner-scoped)
# ---------------------------------------------------------------------------

def _list_dict(conn: sqlite3.Connection, row: sqlite3.Row) -> dict:
    members = [
        member["title_id"]
        for member in conn.execute(
            "SELECT title_id FROM list_members WHERE list_id = ? "
            "ORDER BY rowid",
            (row["id"],),
        ).fetchall()
    ]
    profile = conn.execute(
        "SELECT description, updated_at FROM list_profiles WHERE list_id=?",
        (row["id"],),
    ).fetchone()
    return {
        "id": row["id"],
        "owner_key": row["owner_key"],
        "name": row["name"],
        "list_type": row["list_type"],
        "privacy": row["privacy"],
        "description": profile["description"] if profile else "",
        "updated_at": profile["updated_at"] if profile else row["created_at"],
        "members": members,
    }


def get_list(conn: sqlite3.Connection, list_id: str) -> dict | None:
    row = conn.execute(
        "SELECT * FROM lists WHERE id = ?", (list_id,)
    ).fetchone()
    return _list_dict(conn, row) if row else None


def lists_for_account(
    conn: sqlite3.Connection, account_key: str
) -> list[dict]:
    rows = conn.execute(
        "SELECT * FROM lists WHERE owner_key = ? ORDER BY rowid",
        (account_key,),
    ).fetchall()
    return [_list_dict(conn, row) for row in rows]


def find_list_by_name(
    conn: sqlite3.Connection, account_key: str, name: str
) -> dict | None:
    row = conn.execute(
        "SELECT * FROM lists WHERE owner_key = ? AND name = ? COLLATE NOCASE",
        (account_key, name),
    ).fetchone()
    return _list_dict(conn, row) if row else None


def _existing_list_ids(conn: sqlite3.Connection) -> set[str]:
    return {
        row["id"] for row in conn.execute("SELECT id FROM lists").fetchall()
    }


def next_list_id(conn: sqlite3.Connection) -> str:
    taken = _existing_list_ids(conn)
    sequence = 1
    while True:
        candidate = f"ls-5000009{sequence:02d}"
        if candidate not in taken:
            return candidate
        sequence += 1


def create_list(
    conn: sqlite3.Connection,
    account_key: str,
    name: str,
    list_type: str,
    privacy: str,
    description: str = "",
) -> dict:
    list_id = next_list_id(conn)
    conn.execute(
        "INSERT INTO lists (id, owner_key, name, list_type, privacy, "
        "created_at) VALUES (?, ?, ?, ?, ?, ?)",
        (list_id, account_key, name, list_type, privacy, FROZEN_CLOCK),
    )
    conn.execute(
        "INSERT INTO list_profiles(list_id, description, updated_at) "
        "VALUES (?, ?, ?)",
        (list_id, description, FROZEN_CLOCK),
    )
    return {
        "id": list_id,
        "owner_key": account_key,
        "name": name,
        "list_type": list_type,
        "privacy": privacy,
        "description": description,
        "updated_at": FROZEN_CLOCK,
        "members": [],
    }


def list_add_member(
    conn: sqlite3.Connection, list_id: str, title_id: str
) -> str:
    """Idempotent membership add; returns 'added' or 'exists'."""
    cursor = conn.execute(
        "INSERT OR IGNORE INTO list_members (list_id, title_id) "
        "VALUES (?, ?)",
        (list_id, title_id),
    )
    return "added" if cursor.rowcount else "exists"


def list_member_titles(
    conn: sqlite3.Connection, list_id: str
) -> list[dict]:
    rows = conn.execute(
        """
        SELECT titles.* FROM list_members
        JOIN titles ON titles.id = list_members.title_id
        WHERE list_members.list_id = ?
        ORDER BY list_members.rowid
        """,
        (list_id,),
    ).fetchall()
    return [_title_dict(row, conn) for row in rows]


def update_list(
    conn: sqlite3.Connection,
    list_id: str,
    *,
    name: str,
    description: str,
    privacy: str,
) -> dict:
    conn.execute(
        "UPDATE lists SET name=?, privacy=? WHERE id=?",
        (name, privacy, list_id),
    )
    conn.execute(
        "INSERT INTO list_profiles(list_id, description, updated_at) "
        "VALUES (?, ?, ?) ON CONFLICT(list_id) DO UPDATE SET "
        "description=excluded.description, updated_at=excluded.updated_at",
        (list_id, description, FROZEN_CLOCK),
    )
    updated = get_list(conn, list_id)
    if updated is None:
        raise LookupError(list_id)
    return updated


def delete_list(conn: sqlite3.Connection, list_id: str) -> bool:
    return bool(conn.execute("DELETE FROM lists WHERE id=?", (list_id,)).rowcount)


def list_remove_member(
    conn: sqlite3.Connection, list_id: str, title_id: str
) -> bool:
    return bool(
        conn.execute(
            "DELETE FROM list_members WHERE list_id=? AND title_id=?",
            (list_id, title_id),
        ).rowcount
    )


# ---------------------------------------------------------------------------
# Reviews (one editable local review per account and title)
# ---------------------------------------------------------------------------

def reviews_for_title(conn: sqlite3.Connection, title_id: str) -> list[dict]:
    rows = conn.execute(
        "SELECT reviews.*, accounts.display_name FROM reviews JOIN accounts "
        "ON accounts.key=reviews.account_key WHERE reviews.title_id=? "
        "ORDER BY reviews.updated_at DESC, reviews.id DESC",
        (title_id,),
    ).fetchall()
    return [dict(row) for row in rows]


def get_review(conn: sqlite3.Connection, review_id: int) -> dict | None:
    row = conn.execute(
        "SELECT reviews.*, accounts.display_name FROM reviews JOIN accounts "
        "ON accounts.key=reviews.account_key WHERE reviews.id=?",
        (review_id,),
    ).fetchone()
    return dict(row) if row else None


def review_for_account(
    conn: sqlite3.Connection, account_key: str, title_id: str
) -> dict | None:
    row = conn.execute(
        "SELECT * FROM reviews WHERE account_key=? AND title_id=?",
        (account_key, title_id),
    ).fetchone()
    return dict(row) if row else None


def create_review(
    conn: sqlite3.Connection,
    account_key: str,
    title_id: str,
    *,
    summary: str,
    body: str,
    spoiler: bool,
) -> dict:
    cursor = conn.execute(
        "INSERT INTO reviews(account_key,title_id,summary,body,spoiler,created_at,updated_at) "
        "VALUES (?,?,?,?,?,?,?)",
        (account_key, title_id, summary, body, int(spoiler), FROZEN_CLOCK, FROZEN_CLOCK),
    )
    result = get_review(conn, int(cursor.lastrowid))
    if result is None:
        raise RuntimeError("review insert was not readable")
    return result


def update_review(
    conn: sqlite3.Connection,
    review_id: int,
    *,
    summary: str,
    body: str,
    spoiler: bool,
) -> dict:
    conn.execute(
        "UPDATE reviews SET summary=?, body=?, spoiler=?, updated_at=? WHERE id=?",
        (summary, body, int(spoiler), FROZEN_CLOCK, review_id),
    )
    result = get_review(conn, review_id)
    if result is None:
        raise LookupError(review_id)
    return result


def delete_review(conn: sqlite3.Connection, review_id: int) -> bool:
    return bool(conn.execute("DELETE FROM reviews WHERE id=?", (review_id,)).rowcount)


# ---------------------------------------------------------------------------
# Introspection helpers (tests + health)
# ---------------------------------------------------------------------------

def journal_mode(conn: sqlite3.Connection) -> str:
    return conn.execute("PRAGMA journal_mode").fetchone()[0]


def store_snapshot(account_keys: Iterable[str] = ("alex", "jordan")) -> dict:
    """Legacy-shaped snapshot of all account state (test compatibility)."""
    ensure_database()
    conn = connect()
    try:
        accounts: dict[str, dict] = {}
        for key in account_keys:
            accounts[key] = {
                "watchlist": watchlist_title_ids(conn, key),
                "ratings": ratings_for_account(conn, key),
                "lists": {
                    item["id"]: item for item in lists_for_account(conn, key)
                },
            }
        return {"accounts": accounts}
    finally:
        conn.close()