clay-borg/crates/cb-render-html/src/lib.rs

//! `cb-render-html` — stage 1's renderer (ADR-0007).
//!
//! Emits HTML with inline SVG and one small piece of inline JavaScript;
//! the browser draws it. **Marginal AM-4a cost: zero** — this crate has no
//! third-party dependencies at all, and adding one requires an argument
//! against ADR-0007 §Decision 3.
//!
//! ## What this is not
//!
//! It is **not** `cb-render-api`, and there is no `cb-render-null`.
//! ADR-0007 Decision 2 withdrew the port: a capability port designed
//! against one implementation that emits whole documents acquires a
//! document's shape, and stage 2's `wgpu` renderer would find it
//! unimplementable. INTENT's rule is the one that binds —
//!
//! > *No concept becomes canonical merely because it looks general. It
//! > becomes canonical after surviving a second concrete use.*
//!
//! — so this renders against the existing [`cb_game_runtime::Project`]
//! trait, which is a real interface with real implementations, and the
//! port is declared at stage 2 when there are two.
//!
//! ## The controls, and why they exist
//!
//! CB-WP-0011 established that a renderer's defect class is **silent
//! omission**: every assertion a renderer test naturally makes is
//! satisfied by a renderer showing a third of the state. This crate moves
//! the interactive half of stage 1 into a language `cargo test`,
//! `clippy` and `M-D1-MUT` cannot reach, so two controls carry that
//! finding across the boundary:
//!
//! * [`input`] — **JavaScript may not construct commands.** The page
//!   reports raw pointer facts; Rust decides what they mean, against the
//!   legal list the aggregate already offered.
//! * the coverage gate below — asserts over the **parsed emitted
//!   document**, not over the Rust that emits it. Asserting over the
//!   emitting code would reproduce CB-WP-0011's original defect one layer
//!   up.
//!
//! And [`serve`] carries the four that make a loopback listener safe to
//! have, of which the load-bearing one is a test that a token-less request
//! is refused.

pub mod doc;
pub mod input;
#[cfg(any(test, feature = "js-harness"))]
pub mod jsrun;
pub mod serve;

pub use doc::{document, text_of, Endpoints};

/// The endpoint pair every test in this crate posts to.
#[cfg(test)]
const TEST_ENDPOINTS: Endpoints<'static> = Endpoints {
    command: "/command?t=x",
    note: "/note?t=x",
};
pub use input::{resolve, Note, PointerFact};
pub use serve::{Guard, Refusal, Request};

#[cfg(test)]
mod coverage {
    //! **ADR-0007 control 6.** The HTML counterpart of `cb-play`'s
    //! `every_view_field_is_classified`.
    //!
    //! Same shape as CB-WP-0011's gate, one layer further out: walk the
    //! serialized `GroundView` for every leaf *path*, and require each to
    //! be either rendered — with a token that must appear in the **parsed
    //! document** — or omitted with a stated reason. A new field on
    //! `GroundView` that is in neither list fails the build.
    //!
    //! Paths, not keys: `problem` occurs under a DARVO target, a GROUND
    //! choice and a Selection, and a key-set walk would let one vouch for
    //! the other two.

    use cb_kernel::PlayerId;
    use games_ground::view::GroundView;

    use crate::doc::{document, text_of};

    /// Every leaf path in the serialized view.
    fn paths(v: &serde_json::Value, prefix: &str, out: &mut Vec<String>) {
        match v {
            serde_json::Value::Object(m) if !m.is_empty() => {
                for (k, val) in m {
                    let p = if prefix.is_empty() {
                        k.clone()
                    } else {
                        format!("{prefix}.{k}")
                    };
                    paths(val, &p, out);
                }
            }
            serde_json::Value::Array(a) if !a.is_empty() => {
                for item in a {
                    paths(item, &format!("{prefix}.*"), out);
                }
            }
            _ => out.push(prefix.to_string()),
        }
    }

    /// Collapse map keys to `*` so the classification is over fields, not
    /// over whichever seats and priorities the fixture happens to hold.
    fn normalize(path: &str) -> String {
        const MAPS: &[&str] = &[
            "players",
            "relations",
            "problems",
            "focus",
            "selections",
            "ground_modes",
            "ground_choices",
            "support_responses",
            "darvo_targets",
            "personal",
        ];
        let mut parts: Vec<String> = Vec::new();
        let mut prev_is_map = false;
        for seg in path.split('.') {
            if prev_is_map && seg != "*" {
                parts.push("*".to_string());
            } else {
                parts.push(seg.to_string());
            }
            prev_is_map = MAPS.contains(&seg);
        }
        parts.join(".")
    }

    /// `(leaf path, a token the parsed document must contain)`.
    const RENDERED: &[(&str, &str)] = &[
        ("round", "round 3"),
        ("lead", "lead P2"),
        ("step", "step Select"),
        ("mode", "scoring BondedCoalitions"),
        ("viewer", "viewing as P1"),
        ("solution_deck_len", "draw pile: 17 remaining"),
        ("solution_discard.*.suit", "discard Repair Change"),
        ("players.*.stress", "stress 5"),
        ("players.*.protection", "protect 2"),
        ("players.*.darvo", "darvo Reverse"),
        ("players.*.freedom_ready", "READY"),
        ("players.*.freedom_gate_lifted", "gate lifted"),
        ("players.*.blame_from.*", "blamed by P3"),
        // The empty case is a leaf path of its own, and renders as an
        // explicit absence rather than as nothing at all.
        ("players.*.blame_from", "blamed by none"),
        ("players.*.hand.*.suit", "hand Clarify Boundary"),
        ("players.*.hand_size", "cards)"),
        ("relations.*", "Rivalry"),
        ("problems.*.state", "face down"),
        ("problems.*.suit", "Change 6"),
        ("problems.*.value", "Change 6"),
        ("problems.*.denied", "denied"),
        ("problems.*.claimed_by", "claimed by P2"),
        ("problems.*.protected_this_round", "protected"),
        ("focus.*", "\u{2192}P3"),
        ("selections.*.state", "face down"),
        // CB-WP-0020 T04: words, not Debug. These tokens were
        // `action: Attack` / `target: Some(PlayerId(1))` /
        // `problem: Some(7)` — the shape a player was being shown.
        ("selections.*.action", "selected Attack"),
        ("selections.*.target", "Attack on P2"),
        ("selections.*.problem", "for problem 7"),
        ("ground_modes.*", "ground mode Gr"),
        ("ground_choices.*.choice", "ProtectProblem"),
        ("ground_choices.*.problem", "problem: 7 }"),
        ("support_responses.*", "support AcceptBond"),
        ("darvo_targets.*.problem", "problem: Some(1)"),
        ("darvo_targets.*.player", "player: Some(PlayerId(1))"),
        ("outcome.total", "total 9"),
        ("outcome.threshold", "of 12"),
        ("outcome.group_success", "failure"),
        ("outcome.personal.*", "P1 +3"),
        ("outcome.coalitions.*.members.*", "members: [PlayerId(1)"),
        ("outcome.coalitions.*.score", "score: 4"),
        ("outcome.mastery", "mastery +1"),
        ("outcome.winners.*", "winners P1"),
    ];

    /// Deliberate omissions, each with a reason.
    const OMITTED: &[(&str, &str)] = &[(
        "players.*.hand",
        "null for a non-viewer seat; the absence is rendered as a count",
    )];

    fn fixture() -> GroundView {
        crate::testfix::view(Some(PlayerId(0)))
    }

    fn rendered_document(view: &GroundView) -> String {
        text_of(&document(
            view,
            &[],
            crate::TEST_ENDPOINTS.command,
            Some(PlayerId(0)),
            false,
        ))
    }

    #[test]
    fn every_view_field_is_classified_in_the_emitted_document() {
        let view = fixture();
        let json = serde_json::to_value(&view).expect("view serializes");
        let mut raw = Vec::new();
        paths(&json, "", &mut raw);
        let all: std::collections::BTreeSet<String> = raw.iter().map(|p| normalize(p)).collect();

        // EXPECT-VACUOUS floor. A coverage test over zero paths passes
        // trivially, and that is precisely how this check would rot.
        assert!(
            all.len() >= 30,
            "the walk found {} leaf path(s) — it is not walking the view",
            all.len()
        );

        let claimed: std::collections::BTreeSet<&str> = RENDERED
            .iter()
            .map(|(p, _)| *p)
            .chain(OMITTED.iter().map(|(p, _)| *p))
            .collect();

        let unclassified: Vec<&String> = all
            .iter()
            .filter(|p| !claimed.contains(p.as_str()))
            .collect();
        assert!(
            unclassified.is_empty(),
            "unclassified path(s) in GroundView: {unclassified:?} \
             — add each to RENDERED with a token, or to OMITTED with a reason"
        );

        let stale: Vec<&&str> = claimed.iter().filter(|p| !all.contains(**p)).collect();
        assert!(
            stale.is_empty(),
            "classified path(s) no longer exist in GroundView: {stale:?}"
        );

        // The half that makes it a rendering gate rather than a bookkeeping
        // one: the token must be in the *parsed document*.
        let text = rendered_document(&view);
        let missing: Vec<&str> = RENDERED
            .iter()
            .filter(|(_, tok)| !text.contains(tok))
            .map(|(p, _)| *p)
            .collect();
        assert!(
            missing.is_empty(),
            "claimed rendered, but absent from the emitted document: {missing:?}"
        );
    }

    /// The parse must be a parse. If `text_of` returned the raw source, a
    /// token hiding in a comment, a style rule or the script would count
    /// as rendered — which is the loophole control 6 exists to close.
    #[test]
    fn the_parse_does_not_see_script_or_style_contents() {
        let html = "<style>.x{content:'STYLETOKEN'}</style><p id=\"pid\">seen</p>\
                    <script>var s='SCRIPTTOKEN';</script>";
        let text = text_of(html);
        assert!(text.contains("seen"));
        assert!(text.contains("pid"), "element ids are addressable surface");
        assert!(
            !text.contains("STYLETOKEN"),
            "style contents leaked into the text"
        );
        assert!(
            !text.contains("SCRIPTTOKEN"),
            "script contents leaked into the text"
        );
    }

    /// Control 5, asserted at the document level: the emitted JavaScript
    /// must contain no game vocabulary. If a rule ever needs to live in
    /// the page, ADR-0007 says revisit the decision, not widen this.
    #[test]
    fn the_emitted_javascript_contains_no_game_vocabulary() {
        let doc = document(&fixture(), &[], "/command?t=x", Some(PlayerId(0)), false);
        let script = doc
            .split_once("<script>")
            .and_then(|(_, r)| r.rsplit_once("</script>"))
            .map(|(s, _)| s.to_string())
            .expect("the document carries a script");
        for word in [
            "Investigate",
            "Solve",
            "Support",
            "Attack",
            "Ground",
            "darvo",
            "DARVO",
            "stress",
            "freedom",
            "problem",
            "coalition",
            "reveal",
            "resolve",
        ] {
            assert!(
                !script.contains(word),
                "the emitted JavaScript mentions {word:?} — control 5 is breached"
            );
        }
        // And it must still be doing its one job.
        assert!(script.contains("pointerdown") && script.contains("pointerup"));
    }

    /// The renderer must not invent a hand it was never given.
    ///
    /// Scoped deliberately: the *projection's* hiding rules are asserted
    /// where they live, and re-asserting them here would be a duplicated
    /// fact that drifts. What this checks is the renderer's own failure
    /// mode — that `hand: None` renders as an absence, for every seat, and
    /// that a spectator's document contains no open hand at all.
    #[test]
    fn the_renderer_never_invents_a_hand_it_was_not_given() {
        for seat in [0u8, 1, 2] {
            let view = crate::testfix::view(Some(PlayerId(seat)));
            let text = rendered_document(&view);
            let shown = text.matches("cards)").count();
            assert_eq!(
                shown,
                1,
                "P{} sees {shown} open hands in the document; it was given exactly one",
                seat + 1
            );
            assert_eq!(
                text.matches("card(s), hidden").count(),
                2,
                "the other two seats' hands must render as an absence with a count"
            );
        }
        let text = rendered_document(&crate::testfix::view(None));
        assert_eq!(
            text.matches("cards)").count(),
            0,
            "a spectator document shows an open hand"
        );
        assert!(text.contains("a spectator (no hands)"));
    }
}

/// CB-WP-0016 T03: every affordance the page offers must name an element
/// the page actually contains.
///
/// **This is the check that closes the class the human check found.** On
/// 2026-08-02 the maintainer ran `cb-play --serve 0` and could not drag an
/// action onto a seat. Every test in the repo was green. The cause: the
/// visible seat cards carried no `id`, so `seat-{n}` existed only on the
/// 26 px circles inside the relationship graph, while every action card
/// read *"drag Attack onto a seat…"*.
///
/// Nothing could catch it. `jsrun::gesture` feeds element ids straight
/// into a synthetic `{target:{id}}` and never hit-tests, so it establishes
/// *"the script posts the ids it was given"* — never *"there is an element
/// there to give."* The 42-path coverage gate asserts each view field is
/// present in the parsed document, which a `<div>` with no id satisfies.
///
/// So: drive a real game, and at every decision point require that both
/// halves of every offered affordance appear as real `id` attributes.
#[cfg(test)]
mod affordances {
    use std::cell::RefCell;
    use std::rc::Rc;

    use cb_game_runtime::{Project, ScenarioGame, Setup, Viewer};
    use cb_kernel::PlayerId;
    use games_ground::bot::{play, Choice, Policy, RandomPolicy};
    use games_ground::{GroundCommand, GroundState};

    use crate::{doc, input};

    fn fresh(seed: u64) -> GroundState {
        GroundState::setup(
            &Setup {
                players: 3,
                preset: "standard-3p".into(),
                patch: std::collections::BTreeMap::new(),
            },
            seed,
        )
        .expect("a standard 3p deal")
    }

    /// Renders the page at every real decision point and checks it, then
    /// delegates the actual choice.
    ///
    /// Hooking `Policy` rather than re-driving the game by hand matters:
    /// these are the *same* decision points `cb-play --serve` renders at,
    /// with the same `legal` list. A hand-rolled walk would be a second
    /// implementation of the loop, and could agree with itself while
    /// disagreeing with the thing shipped.
    struct CheckingPolicy {
        inner: RandomPolicy,
        checked: Rc<RefCell<usize>>,
    }

    impl Policy for CheckingPolicy {
        fn name(&self) -> &'static str {
            "affordance-checking"
        }

        fn choose(
            &mut self,
            state: &GroundState,
            seat: PlayerId,
            legal: &[GroundCommand],
            may_pass: bool,
        ) -> Choice {
            let view = state.project(Viewer::Player(seat));
            let html = doc::document(&view, legal, "/command?t=x", Some(seat), may_pass);
            let present = doc::drop_keys(&html);

            for cmd in legal {
                let Some((from, to)) = input::affordance(cmd, seat) else {
                    // A command with no affordance is offered through the
                    // numbered-button path instead. That is a stated
                    // shape, not a missing element.
                    continue;
                };
                assert!(
                    present.contains(&from),
                    "the page offers {cmd:?} whose GRAB id {from:?} is not an \
                     element in the document (seat {seat:?}, step {:?})",
                    state.step
                );
                assert!(
                    present.contains(&to),
                    "the page offers {cmd:?} whose DROP id {to:?} is not an \
                     element in the document (seat {seat:?}, step {:?}). \
                     Present ids: {present:?}",
                    state.step
                );
            }
            *self.checked.borrow_mut() += 1;
            self.inner.choose(state, seat, legal, may_pass)
        }
    }

    /// **The check that closes the class the human check found.**
    ///
    /// On 2026-08-02 the maintainer ran `cb-play --serve 0` and could not
    /// drag an action onto a seat. Every test in the repo was green. The
    /// cause: the visible seat cards carried no `id`, so `seat-{n}` existed
    /// only on the 26 px circles inside the relationship graph, while every
    /// action card read *"drag Attack onto a seat…"*.
    ///
    /// Nothing could catch it. `jsrun::gesture` feeds element ids straight
    /// into a synthetic `{target:{id}}` and never hit-tests, so it
    /// establishes *"the script posts the ids it was given"* — never
    /// *"there is an element there to give."* The coverage gate asserts
    /// each view field appears in the parsed document, which a `<div>` with
    /// no id satisfies perfectly.
    ///
    /// An affordance naming an element that does not exist is the
    /// harness-does-nothing shape in the presentation layer, and until now
    /// it had no detector at all.
    #[test]
    fn every_offered_affordance_names_an_element_that_exists() {
        let checked = Rc::new(RefCell::new(0usize));
        for seed in 0..4u64 {
            let mut policies: Vec<Box<dyn Policy>> = (0..3)
                .map(|i| {
                    Box::new(CheckingPolicy {
                        inner: RandomPolicy::new(seed * 10 + i),
                        checked: checked.clone(),
                    }) as Box<dyn Policy>
                })
                .collect();
            play(fresh(seed), &mut policies).expect("a bot game completes");
        }
        // Positive control: a run that rendered nothing would assert
        // nothing and read as a pass — the exact failure this test exists
        // to catch, one level up.
        let n = *checked.borrow();
        assert!(n >= 50, "checked only {n} decision point(s)");
    }

    /// **ADR-0010 Decision 2, property 2.** A target the page marks legal
    /// must resolve.
    ///
    /// If the page can advertise a drop that Rust then refuses, the two
    /// have drifted and the highlighting is *worse* than none — it teaches
    /// the player something false. This walks real games and checks the
    /// emitted `data-targets` against `resolve` itself, so the page's
    /// promise and the referee's answer cannot disagree.
    #[test]
    fn everything_the_page_advertises_actually_resolves() {
        let checked = Rc::new(RefCell::new(0usize));
        for seed in 0..4u64 {
            let mut policies: Vec<Box<dyn Policy>> = (0..3)
                .map(|i| {
                    Box::new(AdvertisedPolicy {
                        inner: RandomPolicy::new(seed * 7 + i),
                        checked: checked.clone(),
                    }) as Box<dyn Policy>
                })
                .collect();
            play(fresh(seed), &mut policies).expect("a bot game completes");
        }
        let n = *checked.borrow();
        assert!(n >= 50, "checked only {n} advertised target(s)");
    }

    struct AdvertisedPolicy {
        inner: RandomPolicy,
        checked: Rc<RefCell<usize>>,
    }

    impl Policy for AdvertisedPolicy {
        fn name(&self) -> &'static str {
            "advertised-target-checking"
        }

        fn choose(
            &mut self,
            state: &GroundState,
            seat: PlayerId,
            legal: &[GroundCommand],
            may_pass: bool,
        ) -> Choice {
            let view = state.project(Viewer::Player(seat));
            let html = doc::document(&view, legal, "/command?t=x", Some(seat), may_pass);

            for (grab, targets) in crate::jsrun::droppables(&html) {
                let Some(spec) = targets else { continue };
                for drop in spec.split(' ').filter(|s| !s.is_empty()) {
                    let fact = crate::PointerFact::new(&grab, drop);
                    assert!(
                        crate::resolve(&fact, legal, seat).is_ok(),
                        "the page advertises {grab} -> {drop} but resolve refuses it \
                         (seat {seat:?}, step {:?})",
                        state.step
                    );
                    *self.checked.borrow_mut() += 1;
                }
            }
            self.inner.choose(state, seat, legal, may_pass)
        }
    }

    /// **The regression test for the defect actually reported**, and the
    /// reason the check above is not sufficient on its own.
    ///
    /// `every_offered_affordance_names_an_element_that_exists` passes on
    /// the broken tree. `seat-0` *did* exist — on the 26 px circle in the
    /// relationship graph — so an existence check over the whole document
    /// cannot see that the seat *card*, which is what the instruction text
    /// points at, was not droppable.
    ///
    /// A seat is drawn twice and both drawings are the seat. This asserts
    /// the card specifically, by requiring the drop key on the element
    /// that also carries `data-viewer` — the card, and nothing else.
    #[test]
    fn every_seat_card_is_a_drop_target_not_only_the_graph_node() {
        let view = crate::testfix::view(Some(PlayerId(0)));
        let html = doc::document(&view, &[], "/command?t=x", Some(PlayerId(0)), false);

        for seat in view.players.keys() {
            let card = format!(
                "data-viewer=\"{}\" data-drop=\"seat-{}\"",
                view.viewer == Some(*seat),
                seat.0
            );
            assert!(
                html.contains(&card),
                "seat {seat:?} has a card that is not a drop target; looked for {card:?}"
            );
        }

        // And the graph node keeps working — someone will have learned to
        // aim at the circle, and this fix must not take that away.
        let keys = doc::drop_keys(&html);
        for seat in view.players.keys() {
            assert!(keys.contains(&format!("seat-{}", seat.0)));
        }
        assert_eq!(
            html.matches("data-drop=\"seat-0\"").count(),
            2,
            "seat 0 should be droppable in exactly two places: card and graph node"
        );
    }
}

#[cfg(test)]
mod gamelog {
    //! CB-WP-0018 T02.

    use crate::doc::{document_with_log, LogLine};
    use cb_kernel::PlayerId;

    fn line(effects: &[&str]) -> LogLine {
        LogLine {
            who: "P1".into(),
            what: "select_action action=SOLVE problem=1".into(),
            effects: effects.iter().map(|s| (*s).to_string()).collect(),
        }
    }

    fn page(log: &[LogLine]) -> String {
        document_with_log(
            &crate::testfix::view(Some(PlayerId(0))),
            &[],
            crate::TEST_ENDPOINTS,
            Some(PlayerId(0)),
            false,
            log,
            &[],
        )
    }

    /// **The case the pass was reported for.** A SOLVE that cannot be
    /// fulfilled produces no events, and a log built only from events
    /// would render nothing for it — reproducing the silence the
    /// maintainer hit when the same move did nothing three rounds
    /// running.
    #[test]
    fn a_command_that_produced_nothing_says_so() {
        let html = page(&[line(&[])]);
        assert!(
            html.contains("no effect"),
            "a command with no events rendered as if it had done something"
        );
        let text = crate::text_of(&html);
        assert!(text.contains("select_action action=SOLVE problem=1"));
    }

    #[test]
    fn effects_are_listed_and_an_empty_log_says_it_is_empty() {
        let text = crate::text_of(&page(&[line(&["problem 1 claimed by P1"])]));
        assert!(text.contains("problem 1 claimed by P1"));
        assert!(
            !text.contains("no effect"),
            "a command WITH effects was marked as having none"
        );
        assert!(crate::text_of(&page(&[])).contains("nothing has happened yet"));
    }
}

/// CB-WP-0024 T02 — the draw and discard stacks as objects on the table.
///
/// The maintainer asked for the piles to be visible and for the discard
/// to show a shuffle when the draw runs out. **The reshuffle is real** —
/// `games/ground/src/lib.rs::draw_solution` implements the U4 default
/// (deterministic reshuffle of the discard; skip the draw if both are
/// empty), which ground-game confirmed on 2026-08-03. So this renders the
/// state in which the next draw triggers it, rather than inventing a rule.
#[cfg(test)]
mod piles {
    use cb_kernel::PlayerId;
    use games_ground::view::GroundView;

    use crate::doc::document;

    fn view() -> GroundView {
        crate::testfix::view(Some(PlayerId(0)))
    }

    fn html(v: &GroundView) -> String {
        document(v, &[], "/command?t=x", Some(PlayerId(0)), false)
    }

    /// The counts must come from the projection, never be recomputed.
    #[test]
    fn both_counts_are_the_views_own_numbers() {
        let mut v = view();
        v.solution_deck_len = 5;
        let doc = crate::text_of(&html(&v));
        assert!(
            doc.contains("draw pile: 5 remaining"),
            "the drawn deck count is not the view's: {doc}"
        );
        let n = v.solution_discard.len();
        assert!(
            doc.contains(&format!("discard pile: {n} remaining")),
            "the drawn discard count is not the view's ({n}): {doc}"
        );
    }

    /// An empty discard is an EMPTY pile, not a missing one. A absent slot
    /// reads as "this game has no discard", which is a different claim.
    #[test]
    fn an_empty_pile_is_drawn_rather_than_omitted() {
        let mut v = view();
        v.solution_discard.clear();
        let doc = crate::text_of(&html(&v));
        assert!(
            doc.contains("discard pile: 0 remaining"),
            "an empty discard vanished instead of rendering as empty: {doc}"
        );
    }

    /// The U4 state: deck empty, discard holding cards. The next draw
    /// reshuffles, and the table should say so.
    #[test]
    fn an_exhausted_deck_says_the_discard_shuffles_back_in() {
        let mut v = view();
        v.solution_deck_len = 0;
        assert!(!v.solution_discard.is_empty(), "fixture needs a discard");
        let doc = crate::text_of(&html(&v));
        assert!(
            doc.contains("shuffles in on next draw"),
            "an exhausted deck did not announce the U4 reshuffle: {doc}"
        );

        // And the negative half: with cards left, no shuffle is promised.
        let mut full = view();
        full.solution_deck_len = 12;
        assert!(
            !crate::text_of(&html(&full)).contains("shuffles in on next draw"),
            "a stocked deck claimed a reshuffle was coming"
        );
    }
}

/// CB-WP-0028 T03 — one overhead table, not three diagrams.
#[cfg(test)]
mod overhead_table {
    use cb_game_runtime::{Project, ScenarioGame, Setup, Viewer};
    use cb_kernel::PlayerId;
    use games_ground::GroundState;

    /// Seat circle centres, read out of the emitted SVG.
    ///
    /// Keyed on `class="seat"`, not on `<circle>`: CB-WP-0029 put token
    /// discs and track stops on the table, which are also circles, and a
    /// looser match reported them as overlapping seats.
    fn seat_centres(html: &str) -> Vec<(f64, f64)> {
        html.match_indices("<circle class=\"seat\" cx=\"")
            .filter_map(|(i, _)| {
                let rest = &html[i + 25..];
                let (x, rest) = rest.split_once("\" cy=\"")?;
                let (y, _) = rest.split_once('"')?;
                Some((x.parse().ok()?, y.parse().ok()?))
            })
            .collect()
    }

    fn view_of(players: u8) -> games_ground::view::GroundView {
        GroundState::setup(
            &Setup {
                players,
                preset: format!("standard-{players}p"),
                patch: Default::default(),
            },
            7,
        )
        .expect("preset")
        .project(Viewer::Player(PlayerId(0)))
    }

    /// **Every seat count lays out, and no two seats land on each other.**
    /// Asserted per count rather than eyeballed at three, which is the
    /// only count anyone ever looks at.
    #[test]
    fn two_through_six_seats_all_lay_out_without_overlap() {
        for players in 2..=6u8 {
            let v = view_of(players);
            let html = crate::doc::document(&v, &[], "/command?t=x", Some(PlayerId(0)), false);

            let seats = seat_centres(&html);
            assert_eq!(
                seats.len(),
                players as usize,
                "{players}p: expected one circle per seat, got {seats:?}"
            );
            for (i, a) in seats.iter().enumerate() {
                for b in &seats[i + 1..] {
                    let d = ((a.0 - b.0).powi(2) + (a.1 - b.1).powi(2)).sqrt();
                    assert!(
                        d > 64.0,
                        "{players}p: two seats are {d:.0}px apart and the circles are r=34 — \
                         they overlap"
                    );
                }
            }
        }
    }

    /// A table where you cannot find yourself is worse than a list.
    #[test]
    fn the_viewers_own_seat_is_marked() {
        let v = view_of(4);
        let html = crate::doc::document(&v, &[], "/command?t=x", Some(PlayerId(0)), false);
        assert!(
            crate::text_of(&html).contains("P1 (you)"),
            "the viewer's seat is not identifiable"
        );
        assert!(
            html.contains("stroke=\"#9cf\" stroke-width=\"3\""),
            "the viewer's seat should also be visually distinct, not only labelled"
        );
        // A spectator has no seat to mark, and must not claim one.
        let spec = GroundState::setup(
            &Setup {
                players: 4,
                preset: "standard-4p".into(),
                patch: Default::default(),
            },
            7,
        )
        .expect("preset")
        .project(Viewer::Spectator);
        assert!(
            !crate::text_of(&crate::doc::document(&spec, &[], "/x", None, false)).contains("(you)"),
            "a spectator was given a seat"
        );
    }

    /// **Observation 1: the seats were ON the table, not around it.**
    /// Every seat circle must lie outside the ellipse.
    #[test]
    fn the_seats_sit_outside_the_table_not_on_it() {
        for players in 2..=6u8 {
            let v = view_of(players);
            let html = crate::doc::document(&v, &[], "/command?t=x", Some(PlayerId(0)), false);
            let (cx, cy, rx, ry) = (380.0f64, 215.0f64, 200.0f64, 118.0f64);
            for (x, y) in seat_centres(&html) {
                // Outside an ellipse: (dx/rx)^2 + (dy/ry)^2 > 1, with the
                // seat's own radius kept clear of the rim.
                let d = ((x - cx) / (rx + 30.0)).powi(2) + ((y - cy) / (ry + 30.0)).powi(2);
                assert!(
                    d > 1.0,
                    "{players}p: a seat at ({x:.0},{y:.0}) is on or inside the table"
                );
            }
        }
    }

    /// **Observations 3 and 4: the table you can see is the table you drop
    /// on, and the game must be playable.** A `table` drop target that is
    /// not the drawn table is why a player could not find where to drop.
    #[test]
    fn the_drawn_table_is_the_drop_target_and_there_is_only_one() {
        let v = view_of(3);
        let html = crate::doc::document(&v, &[], "/command?t=x", Some(PlayerId(0)), false);
        assert_eq!(
            html.matches("data-drop=\"table\"").count(),
            1,
            "two elements claim to be the table; a player cannot tell which to use"
        );
        let table = html
            .split("aria-label=\"the table, seen from above\"")
            .nth(1)
            .and_then(|s| s.split("</svg>").next())
            .expect("one table svg");
        assert!(
            table.contains("data-drop=\"table\""),
            "the drop target is not on the drawn table"
        );
        assert!(
            table.contains("<ellipse"),
            "the drop target should be the surface itself"
        );
    }

    /// **The reason the game became unplayable.** The table was 620px
    /// tall, so the action cards sat a screen below the Problems — and you
    /// cannot drag between two things never on screen together.
    ///
    /// The limit is **derived, not guessed**. A viewport is ~800px tall;
    /// the header costs ~120 and the move controls ~150, leaving ~530 for
    /// the table. The version that broke dragging declared 620. 500 keeps
    /// headroom without being the arbitrary 460 this test first used —
    /// **the original number had no derivation, which is why raising it
    /// here is fixing the measurement rather than lowering a floor.**
    #[test]
    fn the_table_is_short_enough_to_drag_from() {
        let v = view_of(6);
        let html = crate::doc::document(&v, &[], "/command?t=x", Some(PlayerId(0)), false);
        let vb = html
            .split("viewBox=\"0 0 760 ")
            .nth(1)
            .and_then(|s| s.split('"').next())
            .expect("the table declares a viewBox");
        let h: f64 = vb.parse().expect("a number");
        assert!(
            h <= 500.0,
            "the table is {h}px tall; the action cards end up off-screen and \
             dragging to a Problem becomes impossible"
        );
    }

    /// **CB-WP-0029 T02: Stress and DARVO are tracks, not numbers.**
    ///
    /// The track is the point: DARVO arms at Stress 5 (GR-R08), so a
    /// marker approaching the end of a 0–5 track says *"one more Attack
    /// and I trigger"* — which the number 4 does not.
    #[test]
    fn stress_and_darvo_are_tracks_a_player_can_read_ahead_on() {
        let mut v = view_of(3);
        let seats: Vec<PlayerId> = v.players.keys().copied().collect();
        if let Some(p) = v.players.get_mut(&seats[0]) {
            p.stress = 4;
            p.darvo = games_ground::DarvoStage::Deny;
        }
        let html = crate::doc::document(&v, &[], "/command?t=x", Some(seats[0]), false);
        assert!(
            html.contains("<title>Stress 4 of 5</title>"),
            "the Stress track must say where the marker is, out of what"
        );
        assert!(
            html.contains("<title>DARVO Deny</title>"),
            "the DARVO pawn must name its stage"
        );
        // Six stops for Stress, four for DARVO — a track with the wrong
        // number of stops is a picture, not a track.
        let track_stops = html.matches("<circle cx=").count();
        assert!(
            track_stops >= 3 * (6 + 4),
            "three seats need 6 Stress stops and 4 DARVO stops each: {track_stops}"
        );
    }

    /// A seat with nothing renders as a seat with nothing — the empty
    /// case is the one that silently vanishes.
    #[test]
    fn a_seat_with_no_tokens_still_has_its_tracks() {
        let mut v = view_of(2);
        let seats: Vec<PlayerId> = v.players.keys().copied().collect();
        if let Some(p) = v.players.get_mut(&seats[0]) {
            p.stress = 0;
            p.protection = 0;
            p.blame_from.clear();
            p.freedom_ready = false;
            p.darvo = games_ground::DarvoStage::Off;
        }
        let html = crate::doc::document(&v, &[], "/command?t=x", Some(seats[0]), false);
        assert!(html.contains("<title>Stress 0 of 5</title>"));
        assert!(html.contains("<title>DARVO Off</title>"));
        assert!(
            html.contains("<title>Freedom spent</title>"),
            "a spent Freedom disc is still a disc — it flips, it does not vanish"
        );
    }

    /// Lead and Round belong to the table, not to a seat (ADR-0016 D4).
    #[test]
    fn the_lead_and_round_markers_are_on_the_table() {
        let v = view_of(4);
        let html = crate::doc::document(&v, &[], "/command?t=x", Some(PlayerId(0)), false);
        let table = html
            .split("aria-label=\"the table, seen from above\"")
            .nth(1)
            .and_then(|s| s.split("</svg>").next())
            .expect("one table svg");
        assert!(
            table.contains("Lead marker:"),
            "the Lead marker is not on the table"
        );
        assert!(
            table.contains("Round marker:"),
            "the Round marker is not on the table"
        );
    }

    /// The three diagrams became one: the relationship circle and the
    /// piles picture are gone as separate views, and their content is on
    /// the table.
    #[test]
    fn the_stacks_and_the_relations_are_on_the_table() {
        let v = view_of(3);
        let html = crate::doc::document(&v, &[], "/command?t=x", Some(PlayerId(0)), false);
        let table = html
            .split("aria-label=\"the table, seen from above\"")
            .nth(1)
            .and_then(|s| s.split("</svg>").next())
            .expect("one table svg");
        assert!(
            table.contains("draw pile:"),
            "the draw stack is not on the table"
        );
        assert!(
            table.contains("discard pile:"),
            "the discard is not on the table"
        );
        assert!(
            !html.contains("relationship graph"),
            "the old separate relationship diagram is still being drawn"
        );
    }
}

/// CB-WP-0028 T02 — the cards say what they do, in the edition's words.
#[cfg(test)]
mod card_words {
    use cb_kernel::PlayerId;
    use games_ground::{Action, GroundCommand};

    /// The GROUND card's own tagline reaches the page. This is finding
    /// F18's acceptance test and it has a person attached to it: the
    /// maintainer said he did not understand this card.
    #[test]
    fn the_ground_card_explains_itself_on_the_page() {
        let legal = vec![GroundCommand::SelectAction {
            action: Action::Ground,
            target: None,
            problem: None,
        }];
        let html = crate::doc::document(
            &crate::testfix::view(Some(PlayerId(0))),
            &legal,
            "/command?t=x",
            Some(PlayerId(0)),
            false,
        );
        let text = crate::text_of(&html);
        assert!(
            text.contains("Regulate. Restore the frame. Decide."),
            "the GROUND card's tagline did not reach the page: {text}"
        );
        assert!(
            text.contains("Ground & Restate"),
            "its rules text must be available on demand"
        );
        // From the dataset, not from us.
        let from_edition = games_ground::edition::actions()
            .expect("actions")
            .into_iter()
            .any(|c| c.title == "GROUND" && text.contains(&c.tagline));
        assert!(from_edition, "the tagline on the page is not the edition's");
    }

    /// A Problem shows its own name. The page said `Repair 2` for a card
    /// that reads "Missed Deadline", using columns vendored eight days
    /// earlier and discarded at parse time (ADR-0015 D1).
    #[test]
    fn a_problem_shows_the_name_the_card_has() {
        let titles: Vec<String> = games_ground::edition::problem_texts("SCN_01")
            .expect("SCN_01")
            .into_iter()
            .map(|t| t.title)
            .collect();
        assert!(!titles.is_empty());

        let mut view = crate::testfix::view(Some(PlayerId(0)));
        // Priorities the fixture uses must exist in the edition for the
        // lookup to resolve; use the edition's own.
        let real = games_ground::edition::problem_texts("SCN_01").expect("SCN_01");
        let keys: Vec<u32> = view.problems.keys().copied().collect();
        for (k, t) in keys.iter().zip(real.iter()) {
            if let Some(p) = view.problems.remove(k) {
                view.problems.insert(u32::from(t.priority), p);
            }
        }
        let text = crate::text_of(&crate::doc::document(
            &view,
            &[],
            "/command?t=x",
            Some(PlayerId(0)),
            false,
        ));
        assert!(
            titles.iter().any(|t| text.contains(t.as_str())),
            "no Problem title from the edition appears on the page: {text}"
        );
    }
}

/// CB-WP-0027 T03 — the note channel, and the two things it must not do.
#[cfg(test)]
mod notes {
    use cb_kernel::PlayerId;

    use crate::doc::{document_with_log, text_of};
    use crate::input::{resolve, Note, PointerFact};

    /// **The load-bearing control (ADR-0014 D1).** A note whose text is a
    /// perfectly well-formed pointer fact must not become a move.
    ///
    /// Structural, not vigilance: `Note::parse` returns a `Note`,
    /// `resolve` takes a `PointerFact`, and nothing converts between
    /// them. This asserts the behaviour anyway, because "the types don't
    /// connect" is a claim about code layout until something checks it.
    #[test]
    fn a_note_that_looks_like_a_move_is_not_one() {
        let hostile = "note=down%3Daction-solve%26up%3Dproblem-1";
        let note = Note::parse(hostile).expect("it parses as a note");
        assert_eq!(
            note.text, "down=action-solve&up=problem-1",
            "the text is stored verbatim, uninterpreted"
        );

        // And the command parser refuses the same body outright — the two
        // channels do not overlap even at the wire level.
        assert!(
            PointerFact::parse(hostile).is_err(),
            "the command channel accepted a note body"
        );
        // The reverse, so this is not vacuous: a real pointer fact IS a
        // command, and is NOT a note.
        assert!(PointerFact::parse("down=a&up=b").is_ok());
        assert!(
            Note::parse("down=a&up=b").is_err(),
            "the note channel accepted a pointer fact"
        );

        // Nothing in the crate turns a Note into a command. `resolve`'s
        // signature is the proof; this pins it against a careless change.
        let legal: Vec<games_ground::GroundCommand> = vec![];
        assert!(resolve(&PointerFact::new("x", "y"), &legal, PlayerId(0)).is_err());
    }

    /// An empty note is refused, not stored — a blank row is noise in the
    /// register.
    #[test]
    fn an_empty_note_is_refused() {
        assert!(Note::parse("note=").is_err());
        assert!(Note::parse("note=%20%20").is_err(), "whitespace is empty");
        assert_eq!(
            Note::parse("note=%20hello%20").expect("real text").text,
            "hello",
            "surrounding whitespace is trimmed"
        );
    }

    /// Percent and `+` decoding, since the form posts urlencoded.
    #[test]
    fn the_players_words_survive_the_wire() {
        let n = Note::parse("note=why+is+SOLVE+doing+nothing%3F").expect("parses");
        assert_eq!(n.text, "why is SOLVE doing nothing?");
    }

    /// **The first hostile input this renderer has handled.** Until now
    /// `esc()` escaped suit names.
    #[test]
    fn a_note_containing_markup_renders_as_text() {
        let hostile = "<script>alert(1)</script> & \"quoted\"";
        let html = document_with_log(
            &crate::testfix::view(Some(PlayerId(0))),
            &[],
            crate::TEST_ENDPOINTS,
            Some(PlayerId(0)),
            false,
            &[],
            &[hostile.to_string()],
        );
        assert!(
            !html.contains("<script>alert(1)</script>"),
            "a note's markup reached the document unescaped"
        );
        assert!(
            html.contains("&lt;script&gt;"),
            "the note should still be visible, escaped"
        );
        assert!(
            text_of(&html).contains("alert(1)"),
            "escaping must not eat the player's words — they still read what they wrote"
        );
    }

    /// The comment box is always offered, and the page works without it
    /// being used. A control that appears only sometimes trains a player
    /// not to look for it.
    #[test]
    fn the_comment_box_is_always_there() {
        let html = document_with_log(
            &crate::testfix::view(Some(PlayerId(0))),
            &[],
            crate::TEST_ENDPOINTS,
            Some(PlayerId(0)),
            false,
            &[],
            &[],
        );
        assert!(
            html.contains("action=\"/note?t=x\""),
            "the form must carry the session token"
        );
        assert!(
            html.contains("method=\"post\""),
            "a plain form, so it works with the script disabled"
        );
    }
}

/// CB-WP-0027 T02 — the table on the left, the meta on the right.
#[cfg(test)]
mod two_columns {
    use cb_kernel::PlayerId;

    use crate::doc::document_with_log;

    fn page(meta: &[String]) -> String {
        document_with_log(
            &crate::testfix::view(Some(PlayerId(0))),
            &[],
            crate::TEST_ENDPOINTS,
            Some(PlayerId(0)),
            false,
            &[],
            meta,
        )
    }

    /// The columns exist, and the game is in the left one.
    #[test]
    fn the_table_is_in_the_game_column_and_the_log_is_not() {
        let html = page(&[]);
        let game = html
            .split("class=\"cb-game\"")
            .nth(1)
            .and_then(|s| s.split("class=\"cb-meta\"").next())
            .expect("a game column followed by a meta column");
        assert!(
            game.contains("<h2>the table</h2>"),
            "the table must be in the game column"
        );
        assert!(
            !game.contains("<h2>log</h2>"),
            "the log belongs in the meta column — it is commentary on the game, not part of it"
        );
    }

    /// **A player who writes nothing must not be worse off.** An empty
    /// meta panel renders as nothing, not as an empty heading.
    #[test]
    fn an_empty_meta_panel_adds_no_furniture() {
        assert!(
            !page(&[]).contains("this session"),
            "an empty session panel drew a heading with nothing under it"
        );
        assert!(
            page(&["2 games this session".into()]).contains("this session"),
            "a non-empty panel must appear — otherwise the test above passes for a panel that never renders"
        );
    }

    /// The single-column fallback is deliberate, not incidental. Asserted
    /// on the stylesheet because there is no browser here to resize —
    /// which is a weaker test than laying it out, and is said so rather
    /// than dressed up.
    #[test]
    fn the_layout_collapses_to_one_column_on_a_narrow_viewport() {
        let html = page(&[]);
        assert!(
            html.contains("@media (max-width:64rem)"),
            "no narrow-viewport rule: the two-column layout would overlap on a laptop"
        );
        assert!(
            html.contains("minmax(0,1fr)"),
            "grid children default to min-content width; without minmax(0,…) the SVG table \
             refuses to shrink and pushes the meta column off-screen"
        );
    }
}

/// CB-WP-0024 T03 — what the other seats played, drawn as cards.
///
/// The maintainer could follow the other players only by reading the log.
/// The data was already projected and already rendered — as sentences.
/// This adds the picture without touching the hiding rule, which is the
/// only part that could do harm.
#[cfg(test)]
mod played_cards {
    use cb_kernel::PlayerId;
    use games_ground::view::{GroundView, SelectionView};
    use games_ground::{Action, Selection};

    use crate::doc::document;

    fn html(v: &GroundView) -> String {
        document(v, &[], "/command?t=x", Some(PlayerId(0)), false)
    }

    /// A seat's revealed play is drawn, not only written.
    #[test]
    fn a_revealed_play_is_drawn_as_a_card() {
        let mut v = crate::testfix::view(Some(PlayerId(0)));
        v.selections.insert(
            PlayerId(1),
            SelectionView::Shown(Selection {
                action: Action::Solve,
                target: None,
                problem: Some(3),
            }),
        );
        let doc = html(&v);
        assert!(
            doc.contains("played Solve"),
            "the revealed play was not drawn as a card"
        );
        assert!(
            crate::text_of(&doc).contains("selected Solve"),
            "the sentence must survive alongside the picture — the log is the record"
        );
    }

    /// **The leak test.** Nothing in the emitted document may vary with
    /// another seat's hidden selection.
    ///
    /// The shape is `view.rs`'s own
    /// `a_seat_never_sees_another_seats_face_down_selection`: assert the
    /// absence, then assert the same view AFTER reveal shows it —
    /// otherwise the first assertion passes for a renderer that draws
    /// nothing at all.
    #[test]
    fn a_hidden_play_renders_identically_whatever_it_is() {
        let render_hidden = |action, problem| {
            let mut v = crate::testfix::view(Some(PlayerId(0)));
            // The seat HAS chosen; the viewer may not see what.
            v.selections.insert(PlayerId(1), SelectionView::Hidden);
            // A different real choice underneath, which must not reach us.
            v.selections.insert(
                PlayerId(2),
                SelectionView::Shown(Selection {
                    action,
                    target: None,
                    problem,
                }),
            );
            html(&v)
        };

        // Two different hidden situations must produce the same markup for
        // the hidden seat. Compare the card backs directly.
        let a = render_hidden(Action::Solve, Some(1));
        let b = render_hidden(Action::Attack, Some(9));
        let back = |h: &str| {
            let i = h
                .find("<title>face down</title>")
                .expect("a face-down card");
            h[i.saturating_sub(200)..i + 200].to_string()
        };
        assert_eq!(
            back(&a),
            back(&b),
            "the face-down card differed between two games — it varies with something"
        );

        // The other half: revealed, the same renderer DOES show it.
        let mut shown = crate::testfix::view(Some(PlayerId(0)));
        shown.selections.insert(
            PlayerId(1),
            SelectionView::Shown(Selection {
                action: Action::Attack,
                target: Some(PlayerId(2)),
                problem: None,
            }),
        );
        assert!(
            html(&shown).contains("played Attack"),
            "the assertion above would pass for a renderer that draws nothing"
        );
    }
}

/// CB-WP-0024 T01 — the ending page's one control.
///
/// The maintainer reported it as *"the button says 'I need to read this'
/// — why? the UI is not closing."* Two defects wearing one button: the
/// label described a reading while the control stopped a server, and
/// acknowledging it changed nothing on screen, leaving a live-looking
/// table and a `play again` pointing at a closed port.
#[cfg(test)]
mod ending_page {
    use cb_kernel::PlayerId;

    use crate::{doc, jsrun};

    fn page() -> String {
        doc::ending(None, "the game ended", "/command?t=x", &[], &[])
    }

    /// The label must say what the control DOES. Asserted on the rendered
    /// text so reverting the wording turns this red — a comment would not.
    #[test]
    fn the_control_is_labelled_by_its_effect_not_by_a_reading() {
        let text = crate::text_of(&page());
        assert!(
            text.contains("end session") && text.contains("stops the game server"),
            "the ending control must name its effect: {text}"
        );
        assert!(
            !text.contains("I have read this"),
            "the label claimed the player had read something; it stops a server"
        );
    }

    /// The defect the maintainer actually saw. After the server says the
    /// session is closed, `play again` must stop being offered — it now
    /// points at a port nobody is listening on.
    #[test]
    fn acknowledging_the_end_stops_the_page_offering_anything() {
        let html = page();
        let before = doc::drop_keys(&html);
        assert!(
            before.contains("again") && before.contains("done"),
            "fixture must start with both controls: {before:?}"
        );

        let (live, status) =
            jsrun::gesture_with_reply(&html, "done", "done", "closed — the session has ended")
                .expect("run the page");

        assert!(
            !live.contains(&"again".to_string()),
            "`play again` survived the session ending and would post to a closed port: {live:?}"
        );
        assert!(
            live.is_empty(),
            "every control must be sealed once the server stops, not only `again`: {live:?}"
        );
        assert!(
            status.contains("session has ended"),
            "the page must say what happened: {status:?}"
        );
        // The WHOLE page goes inert, not only the controls. A greyed
        // button beside a full-colour table reads as a live game with one
        // broken control.
        assert!(
            status.contains("sealed-page"),
            "the page itself was not marked ended: {status:?}"
        );
    }

    /// The controls sit **below** the log: you read what happened, then
    /// decide what to do next.
    #[test]
    fn the_controls_come_after_the_log() {
        let html = page();
        let log = html.find("<h2>log</h2>").expect("a log section");
        let again = html
            .find("data-drop=\"again\"")
            .expect("a play-again control");
        assert!(
            again > log,
            "the controls are above the log; the reader decides before reading"
        );
    }

    /// **A thing you click must not look like a thing you drag.**
    ///
    /// Reported two ways at once: *"the button shows a hand to pick up
    /// that it probably shouldn't"* and *"I can't start another game"*.
    /// They are one defect — a grab cursor invites a drag, and a drag
    /// released over nothing posts nothing, so the button looks dead.
    #[test]
    fn click_targets_do_not_wear_the_drag_affordance() {
        let pages = [
            doc::ending(None, "m", "/command?t=x", &[], &[]),
            doc::document(
                &crate::testfix::view(Some(PlayerId(0))),
                &[games_ground::GroundCommand::SelectAction {
                    action: games_ground::Action::Investigate,
                    target: None,
                    problem: Some(2),
                }],
                "/command?t=x",
                Some(PlayerId(0)),
                true,
            ),
        ];
        for html in &pages {
            for key in ["again", "done", "pass"] {
                let Some(i) = html.find(&format!("data-drop=\"{key}\"")) else {
                    continue;
                };
                let tag = &html[html[..i].rfind('<').expect("an opening tag")..i];
                assert!(
                    !tag.contains("pick"),
                    "`{key}` is a click target wearing `.pick`, which is cursor:grab — \
                     it invites a drag, and a drag onto nothing posts nothing"
                );
                assert!(
                    tag.contains("tap"),
                    "`{key}` must still look pressable: {tag}"
                );
            }
        }
        // The inverse, or this passes for a page with no affordances at
        // all: a real draggable still carries `.pick`.
        assert!(
            pages[1].contains("class=\"card act pick\""),
            "action cards must still be draggable"
        );
    }

    /// **CB-WP-0028 T06, asserted both ways.** A test that only checked
    /// the win case would pass for a page that always says "solved".
    #[test]
    fn a_won_game_is_solved_and_a_lost_one_is_over() {
        let mut won = crate::testfix::view(None);
        if let Some(o) = won.outcome.as_mut() {
            o.group_success = true;
        }
        let mut lost = crate::testfix::view(None);
        if let Some(o) = lost.outcome.as_mut() {
            o.group_success = false;
        }
        let head = |v: &games_ground::view::GroundView| {
            crate::text_of(&doc::ending(Some(v), "m", "/command?t=x", &[], &[]))
        };
        assert!(
            head(&won).contains("game solved"),
            "a won game said otherwise"
        );
        assert!(
            !head(&won).contains("game over"),
            "\"game over\" is arcade vocabulary for a failure state"
        );
        assert!(
            head(&lost).contains("game over"),
            "a lost game said otherwise"
        );
        assert!(!head(&lost).contains("game solved"));

        // And a game with no outcome claims neither.
        let none = crate::text_of(&doc::ending(
            None,
            "P1 ran out of input",
            "/command?t=x",
            &[],
            &[],
        ));
        assert!(!none.contains("game solved") && !none.contains("game over"));
    }

    /// **CB-WP-0028 T07.** Every ranking names its source, and the
    /// co-operative mode is not ranked at all — the game says its
    /// tiebreak is "Not applicable", and ranking it anyway would invent
    /// scoring the rules do not have.
    #[test]
    fn a_cooperative_game_shows_contributions_and_refuses_to_rank_them() {
        let mut v = crate::testfix::view(None);
        v.mode = games_ground::ScoringMode::SharedGround;
        let text = crate::text_of(&doc::ending(Some(&v), "m", "/command?t=x", &[], &[]));

        assert!(
            text.contains("problems solved"),
            "the countable fact is missing"
        );
        assert!(
            text.contains("not ranked"),
            "SHARED GROUND must not be ranked: {text}"
        );
        assert!(
            !text.contains("clay-borg's reading"),
            "a reading must not be offered where the game defines no ranking"
        );
    }

    /// And the inverse, or the test above passes for a page that never
    /// ranks anything. A ranked mode cites the GAME's tiebreak and marks
    /// anything derived as ours.
    #[test]
    fn a_ranked_mode_cites_the_games_own_tiebreak() {
        let mut v = crate::testfix::view(None);
        v.mode = games_ground::ScoringMode::BondedCoalitions;
        let text = crate::text_of(&doc::ending(Some(&v), "m", "/command?t=x", &[], &[]));

        assert!(
            text.contains("Lower combined Stress"),
            "the tiebreak shown must be the edition's own words: {text}"
        );
        assert!(
            text.contains("clay-borg&#39;s reading") || text.contains("clay-borg's reading"),
            "a derived superlative must be marked as ours, not as a rule"
        );
    }

    /// The negative control. If `seal` fired on any reply, this test would
    /// pass for a page that tears itself down whenever it is touched —
    /// which would break `play again` in the ordinary case.
    #[test]
    fn a_dealing_reply_leaves_the_controls_alone() {
        let html = page();
        let (live, _) = jsrun::gesture_with_reply(&html, "again", "again", "ok: dealing")
            .expect("run the page");
        assert!(
            live.contains(&"again".to_string()) && live.contains(&"done".to_string()),
            "an 'ok' reply must not seal the page: {live:?}"
        );
        let (_, status) =
            jsrun::gesture_with_reply(&html, "again", "again", "ok: dealing").expect("run");
        assert!(
            !status.contains("sealed-page"),
            "a dealing reply greyed out a page that is about to be reused"
        );
    }
}

#[cfg(test)]
mod testfix;