settled-reach/server/src/simulation/input.rs

// Input processing system
// Timestamped player input events for deterministic simulation (D-010 principle 4)
// PlayerInput: semantic actions (MoveNorth, Interact, UsePerceptionMode, ToggleStance)

use crate::bridge::types::{PlayerAction, PlayerInput};
use crate::knowledge::{EntityRegistry, StableId};
use crate::perception::vision_cone::{facing_from_delta, Facing};
use crate::simulation::inventory::{
    find_next_slot, occupied_slots_for, CarriedBy, InventorySlot, ItemName, MAX_INVENTORY_SLOTS,
};
use crate::simulation::movement::{MoveIntent, PlayerCharacter, TilePosition};
use crate::simulation::stance::{PlayerMoveCooldown, Stance};
use crate::simulation::time::{SimulationTime, TickRate};
use crate::test_world::reset::{RoomResetTrigger, RoomSnapshots};
use bevy_ecs::prelude::*;
use std::collections::VecDeque;

/// Maximum number of inputs the queue will hold before dropping oldest.
/// Prevents unbounded memory growth from input flooding.
pub const INPUT_QUEUE_CAPACITY: usize = 1000;

/// Queue of pending player inputs, ordered by tick
#[derive(Resource, Debug, Default)]
pub struct InputQueue {
    queue: VecDeque<PlayerInput>,
}

impl InputQueue {
    /// Add a new input to the queue.
    /// Inputs must be pushed in tick order for deterministic processing.
    /// Panics in debug builds if tick ordering is violated.
    /// Drops oldest inputs when capacity is exceeded.
    pub fn push(&mut self, input: PlayerInput) {
        debug_assert!(
            self.queue.back().is_none_or(|last| last.tick <= input.tick),
            "InputQueue: tick ordering violated (last={}, new={})",
            self.queue.back().map_or(0, |last| last.tick),
            input.tick,
        );
        if self.queue.len() >= INPUT_QUEUE_CAPACITY {
            let dropped = self.queue.pop_front();
            tracing::warn!(
                "InputQueue at capacity ({}), dropping oldest input (tick={})",
                INPUT_QUEUE_CAPACITY,
                dropped.map_or(0, |d| d.tick),
            );
        }
        self.queue.push_back(input);
    }

    /// Drain all inputs for ticks <= the given tick
    /// Returns inputs in FIFO order
    pub fn drain_for_tick(&mut self, tick: u64) -> Vec<PlayerInput> {
        let mut result = Vec::new();
        while let Some(front) = self.queue.front() {
            if front.tick <= tick {
                result.push(self.queue.pop_front().unwrap());
            } else {
                break;
            }
        }
        result
    }

    /// Get the current queue length
    pub fn len(&self) -> usize {
        self.queue.len()
    }

    /// Check if the queue is empty
    pub fn is_empty(&self) -> bool {
        self.queue.is_empty()
    }
}

/// Drains InputQueue for the current tick, converts PlayerActions to ECS components.
/// Handles stance toggling (D-053), movement cooldown, and Take/Place verbs (#424).
#[allow(clippy::type_complexity, clippy::too_many_arguments)]
pub fn process_player_input(
    mut input_queue: ResMut<InputQueue>,
    mut time: ResMut<SimulationTime>,
    mut commands: Commands,
    registry: Res<EntityRegistry>,
    mut player_query: Query<
        (
            Entity,
            &TilePosition,
            Option<&mut Stance>,
            Option<&mut PlayerMoveCooldown>,
        ),
        With<PlayerCharacter>,
    >,
    inventory_items: Query<(Entity, &CarriedBy, &ItemName, &InventorySlot)>,
    all_positions: Query<&TilePosition>,
    reset_triggers: Query<&RoomResetTrigger>,
    mut room_snapshots: Option<ResMut<RoomSnapshots>>,
) {
    let current_tick = time.tick;
    let paused = time.paused();
    let inputs = input_queue.drain_for_tick(current_tick);

    // Track whether any movement was attempted this tick (for cooldown tick advance)
    let mut move_attempted = false;

    for input in inputs {
        // Discard all gameplay actions while paused (D-052, R2-OQ-01).
        // Only Pause/Unpause/TeleportToHub are processed — everything else is discarded.
        // TeleportToHub is exempted because it's a Gauntlet QA action (#491).
        if paused
            && !matches!(
                input.action,
                PlayerAction::Pause | PlayerAction::Unpause | PlayerAction::TeleportToHub
            )
        {
            continue;
        }
        match input.action {
            PlayerAction::MoveNorth => {
                move_attempted = true;
                apply_move(&mut player_query, &mut commands, 0, -1);
            }
            PlayerAction::MoveSouth => {
                move_attempted = true;
                apply_move(&mut player_query, &mut commands, 0, 1);
            }
            PlayerAction::MoveEast => {
                move_attempted = true;
                apply_move(&mut player_query, &mut commands, 1, 0);
            }
            PlayerAction::MoveWest => {
                move_attempted = true;
                apply_move(&mut player_query, &mut commands, -1, 0);
            }
            PlayerAction::MoveNortheast => {
                move_attempted = true;
                apply_move(&mut player_query, &mut commands, 1, -1);
            }
            PlayerAction::MoveNorthwest => {
                move_attempted = true;
                apply_move(&mut player_query, &mut commands, -1, -1);
            }
            PlayerAction::MoveSoutheast => {
                move_attempted = true;
                apply_move(&mut player_query, &mut commands, 1, 1);
            }
            PlayerAction::MoveSouthwest => {
                move_attempted = true;
                apply_move(&mut player_query, &mut commands, -1, 1);
            }
            PlayerAction::ToggleStanceUp => {
                if let Ok((_, _, Some(mut stance), _)) = player_query.single_mut() {
                    let new_stance = stance.0.step_up();
                    if new_stance != stance.0 {
                        tracing::debug!("Stance up: {:?} -> {:?}", stance.0, new_stance);
                        stance.0 = new_stance;
                    }
                }
            }
            PlayerAction::ToggleStanceDown => {
                if let Ok((_, _, Some(mut stance), _)) = player_query.single_mut() {
                    let new_stance = stance.0.step_down();
                    if new_stance != stance.0 {
                        tracing::debug!("Stance down: {:?} -> {:?}", stance.0, new_stance);
                        stance.0 = new_stance;
                    }
                }
            }
            PlayerAction::Pause => {
                time.tick_rate = TickRate::Paused;
                tracing::debug!("Simulation paused by player input");
            }
            PlayerAction::Unpause => {
                time.tick_rate = TickRate::Full;
                tracing::debug!("Simulation unpaused by player input");
            }
            PlayerAction::SetTickRate(rate) => {
                time.tick_rate = rate;
                tracing::debug!("Tick rate set to {:?} by player input", rate);
            }
            PlayerAction::Interact {
                target_entity_id,
                ref verb,
            } => match verb.as_deref() {
                Some("Take") => {
                    handle_take(
                        &mut commands,
                        &registry,
                        &player_query,
                        &inventory_items,
                        target_entity_id,
                    );
                }
                Some("Place") => {
                    handle_place(&mut commands, &registry, &player_query, target_entity_id);
                }
                Some("Talk") => {
                    handle_talk(
                        &mut commands,
                        &registry,
                        &player_query,
                        &all_positions,
                        target_entity_id,
                    );
                }
                Some("Confront") => {
                    handle_confront(
                        &mut commands,
                        &registry,
                        &player_query,
                        &all_positions,
                        target_entity_id,
                    );
                }
                Some("Reset") => {
                    handle_reset(
                        &mut commands,
                        &registry,
                        &reset_triggers,
                        &mut room_snapshots,
                        target_entity_id,
                        current_tick,
                    );
                }
                _ => {
                    tracing::info!(
                        "Interact: target={:?}, verb={:?} — logged only",
                        target_entity_id,
                        verb,
                    );
                }
            },
            PlayerAction::WalkAway => {
                if let Ok((player_entity, _, _, _)) = player_query.single() {
                    commands
                        .entity(player_entity)
                        .insert(crate::simulation::dialogue::WalkAwayRequest);
                    tracing::debug!("WalkAway: marker set on player");
                }
            }
            PlayerAction::TeleportToHub => {
                handle_teleport_to_hub(&mut player_query, &mut commands);
            }
            PlayerAction::UsePerceptionMode(ref mode) => {
                tracing::trace!("UsePerceptionMode({}) — no-op for Sprint 1", mode);
            }
        }
    }

    // If no movement was attempted this tick, still advance cooldown counter
    if !move_attempted {
        if let Ok((_, _, _, Some(mut cooldown))) = player_query.single_mut() {
            cooldown.tick();
        }
    }
}

/// Apply a movement action with stance-based cooldown enforcement.
/// If the player has a Stance and PlayerMoveCooldown, movement is throttled
/// according to the stance's ticks_per_move. Without these components,
/// movement is unrestricted (backward compatibility).
#[allow(clippy::type_complexity)]
fn apply_move(
    player_query: &mut Query<
        (
            Entity,
            &TilePosition,
            Option<&mut Stance>,
            Option<&mut PlayerMoveCooldown>,
        ),
        With<PlayerCharacter>,
    >,
    commands: &mut Commands,
    dx: i32,
    dy: i32,
) {
    let (entity, pos, stance_opt, cooldown_opt) = player_query
        .single_mut()
        .expect("PlayerCharacter entity must exist when processing input");

    let stance = stance_opt.map(|s| s.0).unwrap_or_default();

    // Check cooldown if present
    if let Some(mut cooldown) = cooldown_opt {
        if !cooldown.try_move(stance) {
            tracing::trace!("Movement throttled by stance {:?} cooldown", stance);
            return;
        }
    }

    commands.entity(entity).insert(MoveIntent {
        target: TilePosition::new(pos.x + dx, pos.y + dy, pos.z),
    });
    // Update facing direction based on movement (D-015 vision cone)
    commands
        .entity(entity)
        .insert(Facing(facing_from_delta(dx, dy)));
}

/// Handle Take verb: pick up an item entity and add it to the player's inventory.
/// Removes TilePosition (item is no longer on the ground — info boundary enforcement),
/// adds CarriedBy + InventorySlot components.
#[allow(clippy::type_complexity)]
fn handle_take(
    commands: &mut Commands,
    registry: &EntityRegistry,
    player_query: &Query<
        (
            Entity,
            &TilePosition,
            Option<&mut Stance>,
            Option<&mut PlayerMoveCooldown>,
        ),
        With<PlayerCharacter>,
    >,
    inventory_items: &Query<(Entity, &CarriedBy, &ItemName, &InventorySlot)>,
    target_entity_id: Option<u64>,
) {
    let Some(target_id) = target_entity_id else {
        tracing::warn!("Take verb without target_entity_id");
        return;
    };

    let Ok((player_entity, _, _, _)) = player_query.single() else {
        return;
    };

    let Some(player_sid) = registry.to_stable(player_entity) else {
        tracing::error!("Player entity not in EntityRegistry");
        return;
    };

    // Resolve wire ID to ECS entity
    let target_stable = StableId(target_id);
    let Some(target_entity) = registry.to_entity(&target_stable) else {
        tracing::warn!(target_id, "Take: target entity not in registry");
        return;
    };

    // Check inventory capacity
    let occupied = occupied_slots_for(player_sid, inventory_items);
    let Some(slot) = find_next_slot(&occupied) else {
        tracing::info!(
            "Inventory full ({} slots), cannot take item",
            MAX_INVENTORY_SLOTS
        );
        return;
    };

    // Remove TilePosition (item leaves the ground), add CarriedBy + InventorySlot
    commands
        .entity(target_entity)
        .remove::<TilePosition>()
        .insert((CarriedBy(player_sid), InventorySlot(slot)));

    tracing::info!(
        target_id,
        slot,
        "Take: item picked up and added to inventory slot",
    );
}

/// Handle Talk verb: set TalkRequest marker on the player entity for the target NPC.
/// The actual dialogue pipeline runs in process_talk_interaction (dialogue.rs).
/// Server-side range check: Talk requires CLOSE_RANGE (same as interaction system).
#[allow(clippy::type_complexity)]
fn handle_talk(
    commands: &mut Commands,
    registry: &EntityRegistry,
    player_query: &Query<
        (
            Entity,
            &TilePosition,
            Option<&mut Stance>,
            Option<&mut PlayerMoveCooldown>,
        ),
        With<PlayerCharacter>,
    >,
    all_positions: &Query<&TilePosition>,
    target_entity_id: Option<u64>,
) {
    let Some(target_id) = target_entity_id else {
        tracing::warn!("Talk verb without target_entity_id");
        return;
    };

    let Ok((player_entity, player_pos, _, _)) = player_query.single() else {
        return;
    };

    let target_stable = StableId(target_id);
    let Some(target_entity) = registry.to_entity(&target_stable) else {
        tracing::warn!(target_id, "Talk: target entity not in registry");
        return;
    };

    // Server-side range check: reject Talk if target is beyond close range
    if let Ok(target_pos) = all_positions.get(target_entity) {
        let distance = player_pos
            .manhattan_distance(target_pos)
            .unwrap_or(u32::MAX);
        if distance > crate::simulation::interaction::CLOSE_RANGE {
            tracing::info!(
                target_id,
                distance,
                "Talk: target out of range (max {})",
                crate::simulation::interaction::CLOSE_RANGE,
            );
            return;
        }
    }

    commands
        .entity(player_entity)
        .insert(crate::simulation::dialogue::TalkRequest {
            target: target_entity,
        });

    tracing::debug!(target_id, "Talk: TalkRequest marker set on player");
}

/// Handle Confront verb: set ConfrontationDelivered marker on the player entity (#520, D-063).
/// The confrontation response system runs in process_confrontation_response (dialogue.rs).
/// Server-side range check: Confront requires CLOSE_RANGE (same as Talk).
#[allow(clippy::type_complexity)]
fn handle_confront(
    commands: &mut Commands,
    registry: &EntityRegistry,
    player_query: &Query<
        (
            Entity,
            &TilePosition,
            Option<&mut Stance>,
            Option<&mut PlayerMoveCooldown>,
        ),
        With<PlayerCharacter>,
    >,
    all_positions: &Query<&TilePosition>,
    target_entity_id: Option<u64>,
) {
    let Some(target_id) = target_entity_id else {
        tracing::warn!("Confront verb without target_entity_id");
        return;
    };

    let Ok((player_entity, player_pos, _, _)) = player_query.single() else {
        return;
    };

    let target_stable = StableId(target_id);
    let Some(target_entity) = registry.to_entity(&target_stable) else {
        tracing::warn!(target_id, "Confront: target entity not in registry");
        return;
    };

    // Server-side range check: reject Confront if target is beyond close range
    if let Ok(target_pos) = all_positions.get(target_entity) {
        let distance = player_pos
            .manhattan_distance(target_pos)
            .unwrap_or(u32::MAX);
        if distance > crate::simulation::interaction::CLOSE_RANGE {
            tracing::info!(
                target_id,
                distance,
                "Confront: target out of range (max {})",
                crate::simulation::interaction::CLOSE_RANGE,
            );
            return;
        }
    }

    commands
        .entity(player_entity)
        .insert(crate::simulation::dialogue::ConfrontationDelivered {
            target: target_entity,
        });

    tracing::debug!(target_id, "Confront: ConfrontationDelivered marker set on player");
}

/// Handle Place verb: remove an item from inventory and place it on the ground
/// at the player's current position. Removes CarriedBy + InventorySlot, adds
/// TilePosition at the player's current tile.
#[allow(clippy::type_complexity)]
fn handle_place(
    commands: &mut Commands,
    registry: &EntityRegistry,
    player_query: &Query<
        (
            Entity,
            &TilePosition,
            Option<&mut Stance>,
            Option<&mut PlayerMoveCooldown>,
        ),
        With<PlayerCharacter>,
    >,
    target_entity_id: Option<u64>,
) {
    let Some(target_id) = target_entity_id else {
        tracing::warn!("Place verb without target_entity_id");
        return;
    };

    let Ok((_, player_pos, _, _)) = player_query.single() else {
        return;
    };

    let target_stable = StableId(target_id);
    let Some(target_entity) = registry.to_entity(&target_stable) else {
        tracing::warn!(target_id, "Place: target entity not in registry");
        return;
    };

    let place_pos = *player_pos;

    // Remove inventory components, place item at player's tile
    commands
        .entity(target_entity)
        .remove::<CarriedBy>()
        .remove::<InventorySlot>()
        .insert(place_pos);

    tracing::info!(
        target_id,
        x = place_pos.x,
        y = place_pos.y,
        z = place_pos.z,
        "Place: item dropped at player position",
    );
}

/// Handle Reset verb: restore a room's entities to their initial positions.
/// Target entity must have a RoomResetTrigger component. Respects debounce.
fn handle_reset(
    commands: &mut Commands,
    registry: &EntityRegistry,
    reset_triggers: &Query<&RoomResetTrigger>,
    room_snapshots: &mut Option<ResMut<RoomSnapshots>>,
    target_entity_id: Option<u64>,
    current_tick: u64,
) {
    let Some(target_id) = target_entity_id else {
        tracing::warn!("Reset verb without target_entity_id");
        return;
    };

    let Some(snapshots) = room_snapshots.as_mut() else {
        tracing::warn!("Reset verb but RoomSnapshots resource not available");
        return;
    };

    let target_stable = StableId(target_id);
    let Some(target_entity) = registry.to_entity(&target_stable) else {
        tracing::warn!(target_id, "Reset: target entity not in registry");
        return;
    };

    let Ok(trigger) = reset_triggers.get(target_entity) else {
        tracing::warn!(target_id, "Reset: target is not a reset trigger");
        return;
    };

    let Some(changes) = snapshots.plan_reset(&trigger.room_name, current_tick) else {
        tracing::info!(
            room = trigger.room_name.as_str(),
            "Reset: debounced or unknown room"
        );
        return;
    };

    let mut restored = 0;
    for (entity, position, is_floor_item) in changes {
        if is_floor_item {
            commands
                .entity(entity)
                .remove::<CarriedBy>()
                .remove::<InventorySlot>()
                .insert(position);
        } else {
            commands.entity(entity).insert(position);
        }
        restored += 1;
    }

    tracing::info!(
        room = trigger.room_name.as_str(),
        restored,
        current_tick,
        "Room reset executed via Reset verb"
    );
}

/// Handle TeleportToHub: move player to hub spawn, clear interaction state (#491).
///
/// Gauntlet-only action. On non-Gauntlet maps (feature disabled), logs a warning
/// and returns. On Gauntlet maps, moves the player to HUB.spawn and removes
/// dialogue, monologue, and interaction markers to prevent stale state.
///
/// Does NOT affect: room state, inventory, game time, knowledge graph.
#[allow(clippy::type_complexity)]
fn handle_teleport_to_hub(
    player_query: &mut Query<
        (
            Entity,
            &TilePosition,
            Option<&mut Stance>,
            Option<&mut PlayerMoveCooldown>,
        ),
        With<PlayerCharacter>,
    >,
    commands: &mut Commands,
) {
    #[cfg(not(feature = "gauntlet"))]
    {
        tracing::warn!("TeleportToHub rejected: not a Gauntlet map");
        return;
    }

    #[cfg(feature = "gauntlet")]
    {
        let Ok((player_entity, _, _, _)) = player_query.single() else {
            return;
        };

        let hub_spawn = crate::test_world::constants::HUB.spawn;

        // Move player to hub spawn
        commands.entity(player_entity).insert(hub_spawn);

        // Clear any pending movement
        commands.entity(player_entity).remove::<MoveIntent>();

        // Clear dialogue/interaction markers
        commands
            .entity(player_entity)
            .remove::<crate::simulation::dialogue::TalkRequest>()
            .remove::<crate::simulation::dialogue::ActiveDialogue>()
            .remove::<crate::simulation::dialogue::WalkAwayRequest>();

        tracing::info!(
            x = hub_spawn.x,
            y = hub_spawn.y,
            z = hub_spawn.z,
            "TeleportToHub: player moved to hub spawn"
        );
    }
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn drain_returns_inputs_up_to_tick() {
        let mut queue = InputQueue::default();
        queue.push(PlayerInput {
            tick: 1,
            action: PlayerAction::MoveNorth,
        });
        queue.push(PlayerInput {
            tick: 2,
            action: PlayerAction::MoveSouth,
        });
        queue.push(PlayerInput {
            tick: 5,
            action: PlayerAction::Interact {
                target_entity_id: None,
                verb: None,
            },
        });
        let inputs = queue.drain_for_tick(3);
        assert_eq!(inputs.len(), 2);
        assert_eq!(queue.len(), 1);
    }

    #[test]
    fn drain_empty_queue_returns_empty() {
        let mut queue = InputQueue::default();
        let inputs = queue.drain_for_tick(10);
        assert!(inputs.is_empty());
    }

    #[test]
    #[should_panic(expected = "tick ordering violated")]
    fn push_rejects_out_of_order_in_debug() {
        let mut queue = InputQueue::default();
        queue.push(PlayerInput {
            tick: 5,
            action: PlayerAction::MoveNorth,
        });
        queue.push(PlayerInput {
            tick: 2,
            action: PlayerAction::MoveSouth,
        });
    }

    #[test]
    fn process_input_move_creates_intent() {
        let mut world = bevy_ecs::world::World::new();
        world.insert_resource(InputQueue::default());
        world.insert_resource(SimulationTime::default());
        world.init_resource::<crate::knowledge::EntityRegistry>();

        let player = world
            .spawn((PlayerCharacter, TilePosition::new(5, 5, 0)))
            .id();

        world.resource_mut::<InputQueue>().push(PlayerInput {
            tick: 0,
            action: PlayerAction::MoveNorth,
        });

        let mut schedule = bevy_ecs::schedule::Schedule::default();
        schedule.add_systems(process_player_input);
        schedule.run(&mut world);

        let intent = world.get::<MoveIntent>(player).unwrap();
        assert_eq!(intent.target, TilePosition::new(5, 4, 0));
    }

    #[test]
    fn process_input_pause_sets_paused() {
        let mut world = bevy_ecs::world::World::new();
        world.insert_resource(InputQueue::default());
        world.insert_resource(SimulationTime::default());
        world.init_resource::<crate::knowledge::EntityRegistry>();

        world.resource_mut::<InputQueue>().push(PlayerInput {
            tick: 0,
            action: PlayerAction::Pause,
        });

        let mut schedule = bevy_ecs::schedule::Schedule::default();
        schedule.add_systems(process_player_input);
        schedule.run(&mut world);

        assert_eq!(
            world.resource::<SimulationTime>().tick_rate,
            TickRate::Paused
        );
    }

    #[test]
    fn process_input_set_tick_rate() {
        let mut world = bevy_ecs::world::World::new();
        world.insert_resource(InputQueue::default());
        world.insert_resource(SimulationTime::default());
        world.init_resource::<crate::knowledge::EntityRegistry>();

        world.resource_mut::<InputQueue>().push(PlayerInput {
            tick: 0,
            action: PlayerAction::SetTickRate(TickRate::Half),
        });

        let mut schedule = bevy_ecs::schedule::Schedule::default();
        schedule.add_systems(process_player_input);
        schedule.run(&mut world);

        assert_eq!(world.resource::<SimulationTime>().tick_rate, TickRate::Half);
    }

    #[test]
    #[should_panic(expected = "PlayerCharacter entity must exist")]
    fn process_input_no_player_panics() {
        let mut world = bevy_ecs::world::World::new();
        world.insert_resource(InputQueue::default());
        world.insert_resource(SimulationTime::default());
        world.init_resource::<crate::knowledge::EntityRegistry>();

        world.resource_mut::<InputQueue>().push(PlayerInput {
            tick: 0,
            action: PlayerAction::MoveNorth,
        });

        let mut schedule = bevy_ecs::schedule::Schedule::default();
        schedule.add_systems(process_player_input);
        schedule.run(&mut world);
    }

    #[test]
    fn process_input_future_tick_ignored() {
        let mut world = bevy_ecs::world::World::new();
        world.insert_resource(InputQueue::default());
        world.insert_resource(SimulationTime::default());
        world.init_resource::<crate::knowledge::EntityRegistry>();

        let player = world
            .spawn((PlayerCharacter, TilePosition::new(5, 5, 0)))
            .id();

        world.resource_mut::<InputQueue>().push(PlayerInput {
            tick: 5,
            action: PlayerAction::MoveNorth,
        });

        let mut schedule = bevy_ecs::schedule::Schedule::default();
        schedule.add_systems(process_player_input);
        schedule.run(&mut world);

        // No MoveIntent should be created (input for future tick)
        assert!(world.get::<MoveIntent>(player).is_none());
    }

    use crate::bridge::types::MovementStance;

    #[test]
    fn toggle_stance_up_changes_stance() {
        let mut world = bevy_ecs::world::World::new();
        world.insert_resource(InputQueue::default());
        world.insert_resource(SimulationTime::default());
        world.init_resource::<crate::knowledge::EntityRegistry>();

        world.spawn((
            PlayerCharacter,
            TilePosition::new(5, 5, 0),
            Stance::default(),
            PlayerMoveCooldown::default(),
        ));

        world.resource_mut::<InputQueue>().push(PlayerInput {
            tick: 0,
            action: PlayerAction::ToggleStanceUp,
        });

        let mut schedule = bevy_ecs::schedule::Schedule::default();
        schedule.add_systems(process_player_input);
        schedule.run(&mut world);

        let mut query = world.query::<&Stance>();
        let stance = query.single(&world).unwrap();
        assert_eq!(stance.0, MovementStance::Sprint);
    }

    #[test]
    fn toggle_stance_down_changes_stance() {
        let mut world = bevy_ecs::world::World::new();
        world.insert_resource(InputQueue::default());
        world.insert_resource(SimulationTime::default());
        world.init_resource::<crate::knowledge::EntityRegistry>();

        world.spawn((
            PlayerCharacter,
            TilePosition::new(5, 5, 0),
            Stance::default(),
            PlayerMoveCooldown::default(),
        ));

        world.resource_mut::<InputQueue>().push(PlayerInput {
            tick: 0,
            action: PlayerAction::ToggleStanceDown,
        });

        let mut schedule = bevy_ecs::schedule::Schedule::default();
        schedule.add_systems(process_player_input);
        schedule.run(&mut world);

        let mut query = world.query::<&Stance>();
        let stance = query.single(&world).unwrap();
        assert_eq!(stance.0, MovementStance::Careful);
    }

    #[test]
    fn walk_stance_throttles_movement_to_every_2_ticks() {
        let mut world = bevy_ecs::world::World::new();
        world.insert_resource(InputQueue::default());
        world.insert_resource(SimulationTime::default());
        world.init_resource::<crate::knowledge::EntityRegistry>();

        let player = world
            .spawn((
                PlayerCharacter,
                TilePosition::new(5, 5, 0),
                Stance::default(), // Walk
                PlayerMoveCooldown::default(),
            ))
            .id();

        let mut schedule = bevy_ecs::schedule::Schedule::default();
        schedule.add_systems(process_player_input);

        // Tick 0: move north — should succeed (first move)
        world.resource_mut::<InputQueue>().push(PlayerInput {
            tick: 0,
            action: PlayerAction::MoveNorth,
        });
        schedule.run(&mut world);
        assert!(
            world.get::<MoveIntent>(player).is_some(),
            "first move should succeed"
        );

        // Remove MoveIntent (simulating validate_movement consuming it)
        world.entity_mut(player).remove::<MoveIntent>();

        // Tick 0 again: move north — should be throttled (cooldown)
        world.resource_mut::<InputQueue>().push(PlayerInput {
            tick: 0,
            action: PlayerAction::MoveNorth,
        });
        schedule.run(&mut world);
        assert!(
            world.get::<MoveIntent>(player).is_none(),
            "second move should be throttled"
        );

        // Tick 0 again: move north — should succeed (cooldown elapsed)
        world.resource_mut::<InputQueue>().push(PlayerInput {
            tick: 0,
            action: PlayerAction::MoveNorth,
        });
        schedule.run(&mut world);
        assert!(
            world.get::<MoveIntent>(player).is_some(),
            "third move should succeed after cooldown"
        );
    }

    #[test]
    fn sprint_stance_allows_every_tick() {
        let mut world = bevy_ecs::world::World::new();
        world.insert_resource(InputQueue::default());
        world.insert_resource(SimulationTime::default());
        world.init_resource::<crate::knowledge::EntityRegistry>();

        let player = world
            .spawn((
                PlayerCharacter,
                TilePosition::new(5, 5, 0),
                Stance(MovementStance::Sprint),
                PlayerMoveCooldown::default(),
            ))
            .id();

        let mut schedule = bevy_ecs::schedule::Schedule::default();
        schedule.add_systems(process_player_input);

        // First move
        world.resource_mut::<InputQueue>().push(PlayerInput {
            tick: 0,
            action: PlayerAction::MoveNorth,
        });
        schedule.run(&mut world);
        assert!(world.get::<MoveIntent>(player).is_some());
        world.entity_mut(player).remove::<MoveIntent>();

        // Second move — sprint allows every tick
        world.resource_mut::<InputQueue>().push(PlayerInput {
            tick: 0,
            action: PlayerAction::MoveNorth,
        });
        schedule.run(&mut world);
        assert!(
            world.get::<MoveIntent>(player).is_some(),
            "sprint should allow every tick"
        );
    }

    #[test]
    fn no_stance_component_moves_unrestricted() {
        // Backward compatibility: entities without Stance/Cooldown move freely
        let mut world = bevy_ecs::world::World::new();
        world.insert_resource(InputQueue::default());
        world.insert_resource(SimulationTime::default());
        world.init_resource::<crate::knowledge::EntityRegistry>();

        let player = world
            .spawn((PlayerCharacter, TilePosition::new(5, 5, 0)))
            .id();

        let mut schedule = bevy_ecs::schedule::Schedule::default();
        schedule.add_systems(process_player_input);

        world.resource_mut::<InputQueue>().push(PlayerInput {
            tick: 0,
            action: PlayerAction::MoveNorth,
        });
        schedule.run(&mut world);
        assert!(world.get::<MoveIntent>(player).is_some());
        world.entity_mut(player).remove::<MoveIntent>();

        // Second move immediately — no throttle without components
        world.resource_mut::<InputQueue>().push(PlayerInput {
            tick: 0,
            action: PlayerAction::MoveNorth,
        });
        schedule.run(&mut world);
        assert!(world.get::<MoveIntent>(player).is_some());
    }

    #[test]
    fn take_verb_picks_up_item() {
        let mut world = bevy_ecs::world::World::new();
        world.insert_resource(InputQueue::default());
        world.insert_resource(SimulationTime::default());
        world.init_resource::<crate::knowledge::EntityRegistry>();

        // Spawn player and register
        let player = world
            .spawn((PlayerCharacter, TilePosition::new(5, 5, 0)))
            .id();
        let player_sid = world
            .resource_mut::<crate::knowledge::EntityRegistry>()
            .register(player);

        // Spawn item near player
        let item = world
            .spawn((TilePosition::new(5, 4, 0), ItemName("Manifest Copy".into())))
            .id();
        let item_sid = world
            .resource_mut::<crate::knowledge::EntityRegistry>()
            .register(item);

        // Issue Take verb
        world.resource_mut::<InputQueue>().push(PlayerInput {
            tick: 0,
            action: PlayerAction::Interact {
                target_entity_id: Some(item_sid.0),
                verb: Some("Take".into()),
            },
        });

        let mut schedule = bevy_ecs::schedule::Schedule::default();
        schedule.add_systems(process_player_input);
        schedule.run(&mut world);

        // Item should have CarriedBy + InventorySlot, no TilePosition
        assert!(
            world.get::<TilePosition>(item).is_none(),
            "item should leave the ground"
        );
        let carried = world
            .get::<CarriedBy>(item)
            .expect("item should have CarriedBy");
        assert_eq!(carried.0, player_sid);
        let slot = world
            .get::<InventorySlot>(item)
            .expect("item should have slot");
        assert_eq!(slot.0, 0, "first item goes to slot 0");
    }

    #[test]
    fn place_verb_drops_item() {
        let mut world = bevy_ecs::world::World::new();
        world.insert_resource(InputQueue::default());
        world.insert_resource(SimulationTime::default());
        world.init_resource::<crate::knowledge::EntityRegistry>();

        let player = world
            .spawn((PlayerCharacter, TilePosition::new(5, 5, 0)))
            .id();
        let player_sid = world
            .resource_mut::<crate::knowledge::EntityRegistry>()
            .register(player);

        // Spawn item already in inventory (no TilePosition)
        let item = world
            .spawn((
                CarriedBy(player_sid),
                ItemName("Manifest Copy".into()),
                InventorySlot(0),
            ))
            .id();
        let item_sid = world
            .resource_mut::<crate::knowledge::EntityRegistry>()
            .register(item);

        // Issue Place verb
        world.resource_mut::<InputQueue>().push(PlayerInput {
            tick: 0,
            action: PlayerAction::Interact {
                target_entity_id: Some(item_sid.0),
                verb: Some("Place".into()),
            },
        });

        let mut schedule = bevy_ecs::schedule::Schedule::default();
        schedule.add_systems(process_player_input);
        schedule.run(&mut world);

        // Item should have TilePosition at player's location, no CarriedBy/InventorySlot
        let pos = world
            .get::<TilePosition>(item)
            .expect("item should be on ground");
        assert_eq!(
            *pos,
            TilePosition::new(5, 5, 0),
            "placed at player position"
        );
        assert!(world.get::<CarriedBy>(item).is_none(), "CarriedBy removed");
        assert!(
            world.get::<InventorySlot>(item).is_none(),
            "InventorySlot removed"
        );
    }

    #[test]
    fn take_verb_assigns_sequential_slots() {
        let mut world = bevy_ecs::world::World::new();
        world.insert_resource(InputQueue::default());
        world.insert_resource(SimulationTime::default());
        world.init_resource::<crate::knowledge::EntityRegistry>();

        let player = world
            .spawn((PlayerCharacter, TilePosition::new(5, 5, 0)))
            .id();
        let player_sid = world
            .resource_mut::<crate::knowledge::EntityRegistry>()
            .register(player);

        // Item already in slot 0
        world.spawn((
            CarriedBy(player_sid),
            ItemName("Manifest".into()),
            InventorySlot(0),
        ));

        // New item on the ground
        let item2 = world
            .spawn((TilePosition::new(5, 4, 0), ItemName("Token".into())))
            .id();
        let item2_sid = world
            .resource_mut::<crate::knowledge::EntityRegistry>()
            .register(item2);

        world.resource_mut::<InputQueue>().push(PlayerInput {
            tick: 0,
            action: PlayerAction::Interact {
                target_entity_id: Some(item2_sid.0),
                verb: Some("Take".into()),
            },
        });

        let mut schedule = bevy_ecs::schedule::Schedule::default();
        schedule.add_systems(process_player_input);
        schedule.run(&mut world);

        let slot = world
            .get::<InventorySlot>(item2)
            .expect("item should have slot");
        assert_eq!(slot.0, 1, "second item goes to slot 1");
    }

    #[test]
    fn take_verb_full_inventory_rejected() {
        let mut world = bevy_ecs::world::World::new();
        world.insert_resource(InputQueue::default());
        world.insert_resource(SimulationTime::default());
        world.init_resource::<crate::knowledge::EntityRegistry>();

        let player = world
            .spawn((PlayerCharacter, TilePosition::new(5, 5, 0)))
            .id();
        let player_sid = world
            .resource_mut::<crate::knowledge::EntityRegistry>()
            .register(player);

        // Fill all 9 slots
        for slot in 0..MAX_INVENTORY_SLOTS {
            world.spawn((
                CarriedBy(player_sid),
                ItemName(format!("Item {}", slot)),
                InventorySlot(slot),
            ));
        }

        // Try to take another item
        let item = world
            .spawn((TilePosition::new(5, 4, 0), ItemName("Overflow".into())))
            .id();
        let item_sid = world
            .resource_mut::<crate::knowledge::EntityRegistry>()
            .register(item);

        world.resource_mut::<InputQueue>().push(PlayerInput {
            tick: 0,
            action: PlayerAction::Interact {
                target_entity_id: Some(item_sid.0),
                verb: Some("Take".into()),
            },
        });

        let mut schedule = bevy_ecs::schedule::Schedule::default();
        schedule.add_systems(process_player_input);
        schedule.run(&mut world);

        // Item should still be on the ground
        assert!(
            world.get::<TilePosition>(item).is_some(),
            "item stays on ground"
        );
        assert!(
            world.get::<CarriedBy>(item).is_none(),
            "no CarriedBy when full"
        );
    }

    #[test]
    fn take_then_place_roundtrip() {
        // D-065: full cycle — item on ground → Take → carried → Place → ground again
        let mut world = bevy_ecs::world::World::new();
        world.insert_resource(InputQueue::default());
        world.insert_resource(SimulationTime::default());
        world.init_resource::<crate::knowledge::EntityRegistry>();

        let player = world
            .spawn((PlayerCharacter, TilePosition::new(5, 5, 0)))
            .id();
        let player_sid = world
            .resource_mut::<crate::knowledge::EntityRegistry>()
            .register(player);

        let item = world
            .spawn((TilePosition::new(5, 4, 0), ItemName("Manifest Copy".into())))
            .id();
        let item_sid = world
            .resource_mut::<crate::knowledge::EntityRegistry>()
            .register(item);

        let mut schedule = bevy_ecs::schedule::Schedule::default();
        schedule.add_systems(process_player_input);

        // Step 1: Take
        world.resource_mut::<InputQueue>().push(PlayerInput {
            tick: 0,
            action: PlayerAction::Interact {
                target_entity_id: Some(item_sid.0),
                verb: Some("Take".into()),
            },
        });
        schedule.run(&mut world);

        assert!(
            world.get::<TilePosition>(item).is_none(),
            "item off ground after Take"
        );
        assert_eq!(world.get::<CarriedBy>(item).unwrap().0, player_sid);
        assert_eq!(world.get::<InventorySlot>(item).unwrap().0, 0);

        // Step 2: Place
        world.resource_mut::<InputQueue>().push(PlayerInput {
            tick: 1,
            action: PlayerAction::Interact {
                target_entity_id: Some(item_sid.0),
                verb: Some("Place".into()),
            },
        });
        world.resource_mut::<SimulationTime>().tick = 1;
        schedule.run(&mut world);

        let pos = world
            .get::<TilePosition>(item)
            .expect("item back on ground after Place");
        assert_eq!(
            *pos,
            TilePosition::new(5, 5, 0),
            "placed at player position"
        );
        assert!(
            world.get::<CarriedBy>(item).is_none(),
            "CarriedBy removed after Place"
        );
        assert!(
            world.get::<InventorySlot>(item).is_none(),
            "InventorySlot removed after Place"
        );
    }

    // === Pause Guard Tests (#461, #462, #463) ===
    // Prevent Bug #3 recurrence: player movement while paused.
    // The pause guard at process_player_input discards movement inputs
    // when SimulationTime.tick_rate == TickRate::Paused (D-052).

    #[test]
    fn movement_discarded_while_paused() {
        // #461: Movement input rejected while paused — prevents Bug #3 recurrence.
        let mut world = bevy_ecs::world::World::new();
        world.insert_resource(InputQueue::default());
        let mut time = SimulationTime::default();
        time.tick_rate = TickRate::Paused;
        world.insert_resource(time);
        world.init_resource::<crate::knowledge::EntityRegistry>();

        let player = world
            .spawn((PlayerCharacter, TilePosition::new(5, 5, 0)))
            .id();

        world.resource_mut::<InputQueue>().push(PlayerInput {
            tick: 0,
            action: PlayerAction::MoveNorth,
        });

        let mut schedule = bevy_ecs::schedule::Schedule::default();
        schedule.add_systems(process_player_input);
        schedule.run(&mut world);

        // Movement must be discarded — no MoveIntent created
        assert!(
            world.get::<MoveIntent>(player).is_none(),
            "MoveNorth must be discarded while paused (Bug #3 guard)"
        );
    }

    #[test]
    fn unpause_accepted_while_paused() {
        // #462: Unpause command is the one control action allowed while paused.
        let mut world = bevy_ecs::world::World::new();
        world.insert_resource(InputQueue::default());
        let mut time = SimulationTime::default();
        time.tick_rate = TickRate::Paused;
        world.insert_resource(time);
        world.init_resource::<crate::knowledge::EntityRegistry>();

        // Player entity required for process_player_input (even if no movement)
        world.spawn((PlayerCharacter, TilePosition::new(5, 5, 0)));

        world.resource_mut::<InputQueue>().push(PlayerInput {
            tick: 0,
            action: PlayerAction::Unpause,
        });

        let mut schedule = bevy_ecs::schedule::Schedule::default();
        schedule.add_systems(process_player_input);
        schedule.run(&mut world);

        assert_eq!(
            world.resource::<SimulationTime>().tick_rate,
            TickRate::Full,
            "Unpause must be accepted while paused"
        );
    }

    #[test]
    fn pause_unpause_roundtrip_with_movement() {
        // #463: Full cycle — pause -> move (rejected) -> unpause -> move (accepted).
        let mut world = bevy_ecs::world::World::new();
        world.insert_resource(InputQueue::default());
        world.insert_resource(SimulationTime::default());
        world.init_resource::<crate::knowledge::EntityRegistry>();

        let player = world
            .spawn((PlayerCharacter, TilePosition::new(5, 5, 0)))
            .id();

        let mut schedule = bevy_ecs::schedule::Schedule::default();
        schedule.add_systems(process_player_input);

        // Step 1: Pause
        world.resource_mut::<InputQueue>().push(PlayerInput {
            tick: 0,
            action: PlayerAction::Pause,
        });
        schedule.run(&mut world);
        assert_eq!(
            world.resource::<SimulationTime>().tick_rate,
            TickRate::Paused,
            "Step 1: game should be paused"
        );

        // Step 2: Move while paused — must be rejected
        world.resource_mut::<InputQueue>().push(PlayerInput {
            tick: 0,
            action: PlayerAction::MoveNorth,
        });
        schedule.run(&mut world);
        assert!(
            world.get::<MoveIntent>(player).is_none(),
            "Step 2: movement must be rejected while paused"
        );

        // Step 3: Unpause
        world.resource_mut::<InputQueue>().push(PlayerInput {
            tick: 0,
            action: PlayerAction::Unpause,
        });
        schedule.run(&mut world);
        assert_eq!(
            world.resource::<SimulationTime>().tick_rate,
            TickRate::Full,
            "Step 3: game should be unpaused"
        );

        // Step 4: Move after unpause — must succeed
        world.resource_mut::<InputQueue>().push(PlayerInput {
            tick: 0,
            action: PlayerAction::MoveNorth,
        });
        schedule.run(&mut world);
        assert!(
            world.get::<MoveIntent>(player).is_some(),
            "Step 4: movement must succeed after unpause"
        );
    }

    // === Remaining Pause Guard Tests (#468) ===
    // Edge cases: stance, interact, batch discard, and SetTickRate while paused.

    #[test]
    fn stance_toggle_rejected_while_paused() {
        // #468: Stance toggle rejected while paused.
        let mut world = bevy_ecs::world::World::new();
        world.insert_resource(InputQueue::default());
        let mut time = SimulationTime::default();
        time.tick_rate = TickRate::Paused;
        world.insert_resource(time);
        world.init_resource::<crate::knowledge::EntityRegistry>();

        world.spawn((
            PlayerCharacter,
            TilePosition::new(5, 5, 0),
            Stance::default(), // Walk
            PlayerMoveCooldown::default(),
        ));

        world.resource_mut::<InputQueue>().push(PlayerInput {
            tick: 0,
            action: PlayerAction::ToggleStanceUp,
        });

        let mut schedule = bevy_ecs::schedule::Schedule::default();
        schedule.add_systems(process_player_input);
        schedule.run(&mut world);

        let mut query = world.query::<&Stance>();
        let stance = query.single(&world).unwrap();
        assert_eq!(
            stance.0,
            MovementStance::Walk,
            "Stance toggle must be rejected while paused"
        );
    }

    #[test]
    fn interact_rejected_while_paused() {
        // #468: Interact rejected while paused.
        // This test verifies no panic and no side effects — interact is a no-op while paused.
        let mut world = bevy_ecs::world::World::new();
        world.insert_resource(InputQueue::default());
        let mut time = SimulationTime::default();
        time.tick_rate = TickRate::Paused;
        world.insert_resource(time);
        world.init_resource::<crate::knowledge::EntityRegistry>();

        let player = world
            .spawn((PlayerCharacter, TilePosition::new(5, 5, 0)))
            .id();
        world
            .resource_mut::<crate::knowledge::EntityRegistry>()
            .register(player);

        // Spawn item on the ground
        let item = world
            .spawn((TilePosition::new(5, 4, 0), ItemName("Manifest Copy".into())))
            .id();
        let item_sid = world
            .resource_mut::<crate::knowledge::EntityRegistry>()
            .register(item);

        world.resource_mut::<InputQueue>().push(PlayerInput {
            tick: 0,
            action: PlayerAction::Interact {
                target_entity_id: Some(item_sid.0),
                verb: Some("Take".into()),
            },
        });

        let mut schedule = bevy_ecs::schedule::Schedule::default();
        schedule.add_systems(process_player_input);
        schedule.run(&mut world);

        // Item must remain on ground — Take rejected while paused
        assert!(
            world.get::<TilePosition>(item).is_some(),
            "Item must stay on ground — interact rejected while paused"
        );
        assert!(
            world.get::<CarriedBy>(item).is_none(),
            "Item must not be picked up while paused"
        );
    }

    #[test]
    fn batch_discard_while_paused() {
        // #468: All inputs in a batch discarded while paused (except Pause/Unpause).
        let mut world = bevy_ecs::world::World::new();
        world.insert_resource(InputQueue::default());
        let mut time = SimulationTime::default();
        time.tick_rate = TickRate::Paused;
        world.insert_resource(time);
        world.init_resource::<crate::knowledge::EntityRegistry>();

        let player = world
            .spawn((
                PlayerCharacter,
                TilePosition::new(5, 5, 0),
                Stance::default(),
                PlayerMoveCooldown::default(),
            ))
            .id();

        // Push a batch of mixed inputs — all should be discarded except Unpause
        let queue = &mut world.resource_mut::<InputQueue>();
        queue.push(PlayerInput {
            tick: 0,
            action: PlayerAction::MoveNorth,
        });
        queue.push(PlayerInput {
            tick: 0,
            action: PlayerAction::ToggleStanceUp,
        });
        queue.push(PlayerInput {
            tick: 0,
            action: PlayerAction::SetTickRate(TickRate::Half),
        });

        let mut schedule = bevy_ecs::schedule::Schedule::default();
        schedule.add_systems(process_player_input);
        schedule.run(&mut world);

        // All gameplay actions discarded
        assert!(
            world.get::<MoveIntent>(player).is_none(),
            "Movement discarded in batch"
        );
        let mut query = world.query::<&Stance>();
        let stance = query.single(&world).unwrap();
        assert_eq!(stance.0, MovementStance::Walk, "Stance unchanged in batch");
        assert_eq!(
            world.resource::<SimulationTime>().tick_rate,
            TickRate::Paused,
            "SetTickRate discarded in batch — still paused"
        );
    }

    #[test]
    fn set_tick_rate_rejected_while_paused() {
        // #468 / R2-OQ-01: SetTickRate(Half) while paused is a bug — must be rejected.
        let mut world = bevy_ecs::world::World::new();
        world.insert_resource(InputQueue::default());
        let mut time = SimulationTime::default();
        time.tick_rate = TickRate::Paused;
        world.insert_resource(time);
        world.init_resource::<crate::knowledge::EntityRegistry>();

        world.spawn((PlayerCharacter, TilePosition::new(5, 5, 0)));

        world.resource_mut::<InputQueue>().push(PlayerInput {
            tick: 0,
            action: PlayerAction::SetTickRate(TickRate::Half),
        });

        let mut schedule = bevy_ecs::schedule::Schedule::default();
        schedule.add_systems(process_player_input);
        schedule.run(&mut world);

        assert_eq!(
            world.resource::<SimulationTime>().tick_rate,
            TickRate::Paused,
            "SetTickRate must be rejected while paused (R2-OQ-01)"
        );
    }

    #[test]
    fn take_without_target_id_is_noop() {
        // Edge case: Take verb with no target_entity_id should not panic
        let mut world = bevy_ecs::world::World::new();
        world.insert_resource(InputQueue::default());
        world.insert_resource(SimulationTime::default());
        world.init_resource::<crate::knowledge::EntityRegistry>();

        world.spawn((PlayerCharacter, TilePosition::new(5, 5, 0)));

        world.resource_mut::<InputQueue>().push(PlayerInput {
            tick: 0,
            action: PlayerAction::Interact {
                target_entity_id: None,
                verb: Some("Take".into()),
            },
        });

        let mut schedule = bevy_ecs::schedule::Schedule::default();
        schedule.add_systems(process_player_input);
        schedule.run(&mut world); // should not panic
    }

    #[test]
    fn place_without_target_id_is_noop() {
        // Edge case: Place verb with no target_entity_id should not panic
        let mut world = bevy_ecs::world::World::new();
        world.insert_resource(InputQueue::default());
        world.insert_resource(SimulationTime::default());
        world.init_resource::<crate::knowledge::EntityRegistry>();

        world.spawn((PlayerCharacter, TilePosition::new(5, 5, 0)));

        world.resource_mut::<InputQueue>().push(PlayerInput {
            tick: 0,
            action: PlayerAction::Interact {
                target_entity_id: None,
                verb: Some("Place".into()),
            },
        });

        let mut schedule = bevy_ecs::schedule::Schedule::default();
        schedule.add_systems(process_player_input);
        schedule.run(&mut world); // should not panic
    }

    // === Room Reset Tests (#490) ===

    #[test]
    fn reset_verb_restores_floor_item() {
        // #490: Take a floor item, then Reset verb restores it to original position.
        let mut world = bevy_ecs::world::World::new();
        world.insert_resource(InputQueue::default());
        world.insert_resource(SimulationTime::default());
        world.init_resource::<crate::knowledge::EntityRegistry>();

        // Player
        let player = world
            .spawn((PlayerCharacter, TilePosition::new(5, 5, 0)))
            .id();
        let player_sid = world
            .resource_mut::<crate::knowledge::EntityRegistry>()
            .register(player);

        // Floor item at (5, 4)
        let item = world
            .spawn((TilePosition::new(5, 4, 0), ItemName("Keycard".into())))
            .id();
        let item_sid = world
            .resource_mut::<crate::knowledge::EntityRegistry>()
            .register(item);

        // Reset plate entity
        let plate = world
            .spawn((
                crate::simulation::interaction::Interactable,
                RoomResetTrigger {
                    room_name: "test_room".to_string(),
                },
                TilePosition::new(5, 3, 0),
            ))
            .id();
        let plate_sid = world
            .resource_mut::<crate::knowledge::EntityRegistry>()
            .register(plate);

        // Record snapshot: item is a floor item at its original position
        let mut snapshots = RoomSnapshots::default();
        snapshots.record("test_room", item, TilePosition::new(5, 4, 0), true);
        world.insert_resource(snapshots);

        let mut schedule = bevy_ecs::schedule::Schedule::default();
        schedule.add_systems(process_player_input);

        // Step 1: Take the item
        world.resource_mut::<InputQueue>().push(PlayerInput {
            tick: 0,
            action: PlayerAction::Interact {
                target_entity_id: Some(item_sid.0),
                verb: Some("Take".into()),
            },
        });
        schedule.run(&mut world);

        assert!(
            world.get::<TilePosition>(item).is_none(),
            "Item should be picked up"
        );
        assert_eq!(world.get::<CarriedBy>(item).unwrap().0, player_sid);

        // Step 2: Reset via verb
        world.resource_mut::<InputQueue>().push(PlayerInput {
            tick: 1,
            action: PlayerAction::Interact {
                target_entity_id: Some(plate_sid.0),
                verb: Some("Reset".into()),
            },
        });
        world.resource_mut::<SimulationTime>().tick = 1;
        schedule.run(&mut world);

        // Item should be back on the ground at original position
        let pos = world
            .get::<TilePosition>(item)
            .expect("Item should be restored to ground");
        assert_eq!(
            *pos,
            TilePosition::new(5, 4, 0),
            "Item at original position"
        );
        assert!(
            world.get::<CarriedBy>(item).is_none(),
            "CarriedBy removed after reset"
        );
        assert!(
            world.get::<InventorySlot>(item).is_none(),
            "InventorySlot removed after reset"
        );
    }

    #[test]
    fn reset_verb_debounces() {
        // #490: Reset debounce prevents rapid-fire resets.
        let mut world = bevy_ecs::world::World::new();
        world.insert_resource(InputQueue::default());
        world.insert_resource(SimulationTime::default());
        world.init_resource::<crate::knowledge::EntityRegistry>();

        let _player = world
            .spawn((PlayerCharacter, TilePosition::new(5, 5, 0)))
            .id();

        // NPC entity
        let npc = world.spawn(TilePosition::new(10, 10, 0)).id();
        world
            .resource_mut::<crate::knowledge::EntityRegistry>()
            .register(npc);

        // Reset plate
        let plate = world
            .spawn((
                crate::simulation::interaction::Interactable,
                RoomResetTrigger {
                    room_name: "test_room".to_string(),
                },
                TilePosition::new(5, 3, 0),
            ))
            .id();
        let plate_sid = world
            .resource_mut::<crate::knowledge::EntityRegistry>()
            .register(plate);

        let mut snapshots = RoomSnapshots::default();
        snapshots.record("test_room", npc, TilePosition::new(10, 10, 0), false);
        world.insert_resource(snapshots);

        let mut schedule = bevy_ecs::schedule::Schedule::default();
        schedule.add_systems(process_player_input);

        // First reset at tick 0 — should succeed
        world.resource_mut::<InputQueue>().push(PlayerInput {
            tick: 0,
            action: PlayerAction::Interact {
                target_entity_id: Some(plate_sid.0),
                verb: Some("Reset".into()),
            },
        });
        schedule.run(&mut world);

        // Move NPC to verify debounce blocks second reset
        *world.get_mut::<TilePosition>(npc).unwrap() = TilePosition::new(20, 20, 0);

        // Second reset at tick 5 — should be debounced (< 10 ticks)
        world.resource_mut::<InputQueue>().push(PlayerInput {
            tick: 5,
            action: PlayerAction::Interact {
                target_entity_id: Some(plate_sid.0),
                verb: Some("Reset".into()),
            },
        });
        world.resource_mut::<SimulationTime>().tick = 5;
        schedule.run(&mut world);

        // NPC should still be at moved position (reset was debounced)
        assert_eq!(
            world.get::<TilePosition>(npc).unwrap().x,
            20,
            "NPC not reset — debounced"
        );

        // Third reset at tick 10 — should succeed
        world.resource_mut::<InputQueue>().push(PlayerInput {
            tick: 10,
            action: PlayerAction::Interact {
                target_entity_id: Some(plate_sid.0),
                verb: Some("Reset".into()),
            },
        });
        world.resource_mut::<SimulationTime>().tick = 10;
        schedule.run(&mut world);

        // NPC should be back at original position
        assert_eq!(
            world.get::<TilePosition>(npc).unwrap().x,
            10,
            "NPC reset after debounce elapsed"
        );
    }

    #[test]
    fn reset_verb_without_snapshots_is_noop() {
        // Reset verb when no RoomSnapshots resource exists should not panic.
        let mut world = bevy_ecs::world::World::new();
        world.insert_resource(InputQueue::default());
        world.insert_resource(SimulationTime::default());
        world.init_resource::<crate::knowledge::EntityRegistry>();

        world.spawn((PlayerCharacter, TilePosition::new(5, 5, 0)));

        let plate = world
            .spawn((
                crate::simulation::interaction::Interactable,
                RoomResetTrigger {
                    room_name: "test_room".to_string(),
                },
                TilePosition::new(5, 3, 0),
            ))
            .id();
        let plate_sid = world
            .resource_mut::<crate::knowledge::EntityRegistry>()
            .register(plate);

        // No RoomSnapshots resource inserted — should be gracefully handled
        world.resource_mut::<InputQueue>().push(PlayerInput {
            tick: 0,
            action: PlayerAction::Interact {
                target_entity_id: Some(plate_sid.0),
                verb: Some("Reset".into()),
            },
        });

        let mut schedule = bevy_ecs::schedule::Schedule::default();
        schedule.add_systems(process_player_input);
        schedule.run(&mut world); // should not panic
    }

    // === TeleportToHub Tests (#491) ===

    #[cfg(feature = "gauntlet")]
    #[test]
    fn teleport_to_hub_moves_player() {
        // #491: TeleportToHub moves player to hub spawn position.
        let mut world = bevy_ecs::world::World::new();
        world.insert_resource(InputQueue::default());
        world.insert_resource(SimulationTime::default());
        world.init_resource::<crate::knowledge::EntityRegistry>();

        // Spawn player at a non-hub position
        let player = world
            .spawn((PlayerCharacter, TilePosition::new(84, 58, 0)))
            .id();

        world.resource_mut::<InputQueue>().push(PlayerInput {
            tick: 0,
            action: PlayerAction::TeleportToHub,
        });

        let mut schedule = bevy_ecs::schedule::Schedule::default();
        schedule.add_systems(process_player_input);
        schedule.run(&mut world);

        let pos = world.get::<TilePosition>(player).expect("player has position");
        let hub_spawn = crate::test_world::constants::HUB.spawn;
        assert_eq!(pos.x, hub_spawn.x, "player x at hub spawn");
        assert_eq!(pos.y, hub_spawn.y, "player y at hub spawn");
        assert_eq!(pos.z, hub_spawn.z, "player z at hub spawn");
    }

    #[cfg(feature = "gauntlet")]
    #[test]
    fn teleport_to_hub_clears_dialogue_markers() {
        // #491: TeleportToHub removes ActiveDialogue and TalkRequest.
        let mut world = bevy_ecs::world::World::new();
        world.insert_resource(InputQueue::default());
        world.insert_resource(SimulationTime::default());
        world.init_resource::<crate::knowledge::EntityRegistry>();

        // Spawn a fake NPC target
        let npc = world.spawn(TilePosition::new(10, 10, 0)).id();

        // Spawn player with active dialogue state
        let player = world
            .spawn((
                PlayerCharacter,
                TilePosition::new(84, 58, 0),
                crate::simulation::dialogue::TalkRequest { target: npc },
                crate::simulation::dialogue::ActiveDialogue {
                    target: npc,
                    interaction_type: crate::knowledge::events::InteractionType::Talk,
                    started_tick: 0,
                },
            ))
            .id();

        world.resource_mut::<InputQueue>().push(PlayerInput {
            tick: 0,
            action: PlayerAction::TeleportToHub,
        });

        let mut schedule = bevy_ecs::schedule::Schedule::default();
        schedule.add_systems(process_player_input);
        schedule.run(&mut world);

        assert!(
            world
                .get::<crate::simulation::dialogue::TalkRequest>(player)
                .is_none(),
            "TalkRequest cleared after teleport"
        );
        assert!(
            world
                .get::<crate::simulation::dialogue::ActiveDialogue>(player)
                .is_none(),
            "ActiveDialogue cleared after teleport"
        );
    }

    #[cfg(feature = "gauntlet")]
    #[test]
    fn teleport_to_hub_clears_move_intent() {
        // #491: TeleportToHub removes any pending MoveIntent.
        let mut world = bevy_ecs::world::World::new();
        world.insert_resource(InputQueue::default());
        world.insert_resource(SimulationTime::default());
        world.init_resource::<crate::knowledge::EntityRegistry>();

        let player = world
            .spawn((
                PlayerCharacter,
                TilePosition::new(84, 58, 0),
                MoveIntent {
                    target: TilePosition::new(85, 58, 0),
                },
            ))
            .id();

        world.resource_mut::<InputQueue>().push(PlayerInput {
            tick: 0,
            action: PlayerAction::TeleportToHub,
        });

        let mut schedule = bevy_ecs::schedule::Schedule::default();
        schedule.add_systems(process_player_input);
        schedule.run(&mut world);

        assert!(
            world.get::<MoveIntent>(player).is_none(),
            "MoveIntent cleared after teleport"
        );
    }

    #[cfg(feature = "gauntlet")]
    #[test]
    fn teleport_to_hub_allowed_while_paused() {
        // #491: TeleportToHub is a QA action — allowed even when paused.
        let mut world = bevy_ecs::world::World::new();
        world.insert_resource(InputQueue::default());
        let mut time = SimulationTime::default();
        time.tick_rate = TickRate::Paused;
        world.insert_resource(time);
        world.init_resource::<crate::knowledge::EntityRegistry>();

        let player = world
            .spawn((PlayerCharacter, TilePosition::new(84, 58, 0)))
            .id();

        world.resource_mut::<InputQueue>().push(PlayerInput {
            tick: 0,
            action: PlayerAction::TeleportToHub,
        });

        let mut schedule = bevy_ecs::schedule::Schedule::default();
        schedule.add_systems(process_player_input);
        schedule.run(&mut world);

        let pos = world.get::<TilePosition>(player).expect("player has position");
        let hub_spawn = crate::test_world::constants::HUB.spawn;
        assert_eq!(pos.x, hub_spawn.x, "teleport works while paused");
    }
}