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elevator_core/sim/
construction.rs

1//! Simulation construction, validation, and topology assembly.
2//!
3//! Split out from `sim.rs` to keep each concern readable. Holds:
4//!
5//! - [`Simulation::new`] and [`Simulation::new_with_hooks`]
6//! - Config validation ([`Simulation::validate_config`] and helpers)
7//! - Legacy and explicit topology builders
8//! - [`Simulation::from_parts`] for snapshot restore
9//! - Dispatch, reposition, and hook registration helpers
10//!
11//! Since this is a child module of `crate::sim`, it can access `Simulation`'s
12//! private fields directly — no visibility relaxation required.
13
14use std::collections::{BTreeMap, HashMap, HashSet};
15use std::sync::Mutex;
16
17use crate::components::{Elevator, ElevatorPhase, Line, Orientation, Position, Stop, Velocity};
18use crate::config::SimConfig;
19use crate::dispatch::{
20    BuiltinReposition, BuiltinStrategy, DispatchStrategy, ElevatorGroup, LineInfo,
21    RepositionStrategy,
22};
23use crate::door::DoorState;
24use crate::entity::EntityId;
25use crate::error::SimError;
26use crate::events::EventBus;
27use crate::hooks::{Phase, PhaseHooks};
28use crate::ids::GroupId;
29use crate::metrics::Metrics;
30use crate::rider_index::RiderIndex;
31use crate::stop::StopId;
32use crate::time::TimeAdapter;
33use crate::topology::TopologyGraph;
34use crate::world::World;
35
36use super::Simulation;
37
38/// Bundled topology result: groups, dispatchers, and strategy IDs.
39type TopologyResult = (
40    Vec<ElevatorGroup>,
41    BTreeMap<GroupId, Box<dyn DispatchStrategy>>,
42    BTreeMap<GroupId, BuiltinStrategy>,
43);
44
45impl Simulation {
46    /// Create a new simulation from config and a dispatch strategy.
47    ///
48    /// Returns `Err` if the config is invalid (zero stops, duplicate IDs,
49    /// negative speeds, etc.).
50    ///
51    /// # Errors
52    ///
53    /// Returns [`SimError::InvalidConfig`] if the configuration has zero stops,
54    /// duplicate stop IDs, zero elevators, non-positive physics parameters,
55    /// invalid starting stops, or non-positive tick rate.
56    pub fn new(
57        config: &SimConfig,
58        dispatch: impl DispatchStrategy + 'static,
59    ) -> Result<Self, SimError> {
60        let mut dispatchers = BTreeMap::new();
61        dispatchers.insert(GroupId(0), Box::new(dispatch) as Box<dyn DispatchStrategy>);
62        Self::new_with_hooks(config, dispatchers, PhaseHooks::default())
63    }
64
65    /// Create a simulation with pre-configured lifecycle hooks.
66    ///
67    /// Used by [`SimulationBuilder`](crate::builder::SimulationBuilder).
68    #[allow(clippy::too_many_lines)]
69    pub(crate) fn new_with_hooks(
70        config: &SimConfig,
71        builder_dispatchers: BTreeMap<GroupId, Box<dyn DispatchStrategy>>,
72        hooks: PhaseHooks,
73    ) -> Result<Self, SimError> {
74        Self::validate_config(config)?;
75
76        let mut world = World::new();
77
78        // Create stop entities.
79        let mut stop_lookup: HashMap<StopId, EntityId> = HashMap::new();
80        for sc in &config.building.stops {
81            let eid = world.spawn();
82            world.set_stop(
83                eid,
84                Stop {
85                    name: sc.name.clone(),
86                    position: sc.position,
87                },
88            );
89            world.set_position(eid, Position { value: sc.position });
90            stop_lookup.insert(sc.id, eid);
91        }
92
93        // Build sorted-stops index for O(log n) PassingFloor detection.
94        let mut sorted: Vec<(f64, EntityId)> = world
95            .iter_stops()
96            .map(|(eid, stop)| (stop.position, eid))
97            .collect();
98        sorted.sort_by(|a, b| a.0.total_cmp(&b.0));
99        world.insert_resource(crate::world::SortedStops(sorted));
100
101        let (groups, dispatchers, strategy_ids) = if let Some(line_configs) = &config.building.lines
102        {
103            Self::build_explicit_topology(
104                &mut world,
105                config,
106                line_configs,
107                &stop_lookup,
108                builder_dispatchers,
109            )
110        } else {
111            Self::build_legacy_topology(&mut world, config, &stop_lookup, builder_dispatchers)
112        };
113
114        let dt = 1.0 / config.simulation.ticks_per_second;
115
116        world.insert_resource(crate::tagged_metrics::MetricTags::default());
117
118        // Collect line tag info (entity + name + elevator entities) before
119        // borrowing world mutably for MetricTags.
120        let line_tag_info: Vec<(EntityId, String, Vec<EntityId>)> = groups
121            .iter()
122            .flat_map(|group| {
123                group.lines().iter().filter_map(|li| {
124                    let line_comp = world.line(li.entity())?;
125                    Some((li.entity(), line_comp.name.clone(), li.elevators().to_vec()))
126                })
127            })
128            .collect();
129
130        // Tag line entities and their elevators with "line:{name}".
131        if let Some(tags) = world.resource_mut::<crate::tagged_metrics::MetricTags>() {
132            for (line_eid, name, elevators) in &line_tag_info {
133                let tag = format!("line:{name}");
134                tags.tag(*line_eid, tag.clone());
135                for elev_eid in elevators {
136                    tags.tag(*elev_eid, tag.clone());
137                }
138            }
139        }
140
141        // Wire reposition strategies from group configs.
142        let mut repositioners: BTreeMap<GroupId, Box<dyn RepositionStrategy>> = BTreeMap::new();
143        let mut reposition_ids: BTreeMap<GroupId, BuiltinReposition> = BTreeMap::new();
144        if let Some(group_configs) = &config.building.groups {
145            for gc in group_configs {
146                if let Some(ref repo_id) = gc.reposition
147                    && let Some(strategy) = repo_id.instantiate()
148                {
149                    let gid = GroupId(gc.id);
150                    repositioners.insert(gid, strategy);
151                    reposition_ids.insert(gid, repo_id.clone());
152                }
153            }
154        }
155
156        Ok(Self {
157            world,
158            events: EventBus::default(),
159            pending_output: Vec::new(),
160            tick: 0,
161            dt,
162            groups,
163            stop_lookup,
164            dispatchers,
165            strategy_ids,
166            repositioners,
167            reposition_ids,
168            metrics: Metrics::new(),
169            time: TimeAdapter::new(config.simulation.ticks_per_second),
170            hooks,
171            elevator_ids_buf: Vec::new(),
172            topo_graph: Mutex::new(TopologyGraph::new()),
173            rider_index: RiderIndex::default(),
174        })
175    }
176
177    /// Spawn a single elevator entity from an `ElevatorConfig` onto `line`.
178    ///
179    /// Sets position, velocity, all `Elevator` fields, optional energy profile,
180    /// optional service mode, and an empty `DestinationQueue`.
181    /// Returns the new entity ID.
182    fn spawn_elevator_entity(
183        world: &mut World,
184        ec: &crate::config::ElevatorConfig,
185        line: EntityId,
186        stop_lookup: &HashMap<StopId, EntityId>,
187        start_pos_lookup: &[crate::stop::StopConfig],
188    ) -> EntityId {
189        let eid = world.spawn();
190        let start_pos = start_pos_lookup
191            .iter()
192            .find(|s| s.id == ec.starting_stop)
193            .map_or(0.0, |s| s.position);
194        world.set_position(eid, Position { value: start_pos });
195        world.set_velocity(eid, Velocity { value: 0.0 });
196        let restricted: HashSet<EntityId> = ec
197            .restricted_stops
198            .iter()
199            .filter_map(|sid| stop_lookup.get(sid).copied())
200            .collect();
201        world.set_elevator(
202            eid,
203            Elevator {
204                phase: ElevatorPhase::Idle,
205                door: DoorState::Closed,
206                max_speed: ec.max_speed,
207                acceleration: ec.acceleration,
208                deceleration: ec.deceleration,
209                weight_capacity: ec.weight_capacity,
210                current_load: 0.0,
211                riders: Vec::new(),
212                target_stop: None,
213                door_transition_ticks: ec.door_transition_ticks,
214                door_open_ticks: ec.door_open_ticks,
215                line,
216                repositioning: false,
217                restricted_stops: restricted,
218                inspection_speed_factor: ec.inspection_speed_factor,
219                going_up: true,
220                going_down: true,
221                move_count: 0,
222            },
223        );
224        #[cfg(feature = "energy")]
225        if let Some(ref profile) = ec.energy_profile {
226            world.set_energy_profile(eid, profile.clone());
227            world.set_energy_metrics(eid, crate::energy::EnergyMetrics::default());
228        }
229        if let Some(mode) = ec.service_mode {
230            world.set_service_mode(eid, mode);
231        }
232        world.set_destination_queue(eid, crate::components::DestinationQueue::new());
233        eid
234    }
235
236    /// Build topology from the legacy flat elevator list (single default line + group).
237    fn build_legacy_topology(
238        world: &mut World,
239        config: &SimConfig,
240        stop_lookup: &HashMap<StopId, EntityId>,
241        builder_dispatchers: BTreeMap<GroupId, Box<dyn DispatchStrategy>>,
242    ) -> TopologyResult {
243        let all_stop_entities: Vec<EntityId> = stop_lookup.values().copied().collect();
244        let stop_positions: Vec<f64> = config.building.stops.iter().map(|s| s.position).collect();
245        let min_pos = stop_positions.iter().copied().fold(f64::INFINITY, f64::min);
246        let max_pos = stop_positions
247            .iter()
248            .copied()
249            .fold(f64::NEG_INFINITY, f64::max);
250
251        let default_line_eid = world.spawn();
252        world.set_line(
253            default_line_eid,
254            Line {
255                name: "Default".into(),
256                group: GroupId(0),
257                orientation: Orientation::Vertical,
258                position: None,
259                min_position: min_pos,
260                max_position: max_pos,
261                max_cars: None,
262            },
263        );
264
265        let mut elevator_entities = Vec::new();
266        for ec in &config.elevators {
267            let eid = Self::spawn_elevator_entity(
268                world,
269                ec,
270                default_line_eid,
271                stop_lookup,
272                &config.building.stops,
273            );
274            elevator_entities.push(eid);
275        }
276
277        let default_line_info =
278            LineInfo::new(default_line_eid, elevator_entities, all_stop_entities);
279
280        let group = ElevatorGroup::new(GroupId(0), "Default".into(), vec![default_line_info]);
281
282        // Use builder-provided dispatcher or default Scan.
283        let mut dispatchers = BTreeMap::new();
284        let dispatch = builder_dispatchers.into_iter().next().map_or_else(
285            || Box::new(crate::dispatch::scan::ScanDispatch::new()) as Box<dyn DispatchStrategy>,
286            |(_, d)| d,
287        );
288        dispatchers.insert(GroupId(0), dispatch);
289
290        let mut strategy_ids = BTreeMap::new();
291        strategy_ids.insert(GroupId(0), BuiltinStrategy::Scan);
292
293        (vec![group], dispatchers, strategy_ids)
294    }
295
296    /// Build topology from explicit `LineConfig`/`GroupConfig` definitions.
297    #[allow(clippy::too_many_lines)]
298    fn build_explicit_topology(
299        world: &mut World,
300        config: &SimConfig,
301        line_configs: &[crate::config::LineConfig],
302        stop_lookup: &HashMap<StopId, EntityId>,
303        builder_dispatchers: BTreeMap<GroupId, Box<dyn DispatchStrategy>>,
304    ) -> TopologyResult {
305        // Map line config id → (line EntityId, LineInfo).
306        let mut line_map: HashMap<u32, (EntityId, LineInfo)> = HashMap::new();
307
308        for lc in line_configs {
309            // Resolve served stop entities.
310            let served_entities: Vec<EntityId> = lc
311                .serves
312                .iter()
313                .filter_map(|sid| stop_lookup.get(sid).copied())
314                .collect();
315
316            // Compute min/max from stops if not explicitly set.
317            let stop_positions: Vec<f64> = lc
318                .serves
319                .iter()
320                .filter_map(|sid| {
321                    config
322                        .building
323                        .stops
324                        .iter()
325                        .find(|s| s.id == *sid)
326                        .map(|s| s.position)
327                })
328                .collect();
329            let auto_min = stop_positions.iter().copied().fold(f64::INFINITY, f64::min);
330            let auto_max = stop_positions
331                .iter()
332                .copied()
333                .fold(f64::NEG_INFINITY, f64::max);
334
335            let min_pos = lc.min_position.unwrap_or(auto_min);
336            let max_pos = lc.max_position.unwrap_or(auto_max);
337
338            let line_eid = world.spawn();
339            // The group assignment will be set when we process GroupConfigs.
340            // Default to GroupId(0) initially.
341            world.set_line(
342                line_eid,
343                Line {
344                    name: lc.name.clone(),
345                    group: GroupId(0),
346                    orientation: lc.orientation,
347                    position: lc.position,
348                    min_position: min_pos,
349                    max_position: max_pos,
350                    max_cars: lc.max_cars,
351                },
352            );
353
354            // Spawn elevators for this line.
355            let mut elevator_entities = Vec::new();
356            for ec in &lc.elevators {
357                let eid = Self::spawn_elevator_entity(
358                    world,
359                    ec,
360                    line_eid,
361                    stop_lookup,
362                    &config.building.stops,
363                );
364                elevator_entities.push(eid);
365            }
366
367            let line_info = LineInfo::new(line_eid, elevator_entities, served_entities);
368            line_map.insert(lc.id, (line_eid, line_info));
369        }
370
371        // Build groups from GroupConfigs, or auto-infer a single group.
372        let group_configs = config.building.groups.as_deref();
373        let mut groups = Vec::new();
374        let mut dispatchers = BTreeMap::new();
375        let mut strategy_ids = BTreeMap::new();
376
377        if let Some(gcs) = group_configs {
378            for gc in gcs {
379                let group_id = GroupId(gc.id);
380
381                let mut group_lines = Vec::new();
382
383                for &lid in &gc.lines {
384                    if let Some((line_eid, li)) = line_map.get(&lid) {
385                        // Update the line's group assignment.
386                        if let Some(line_comp) = world.line_mut(*line_eid) {
387                            line_comp.group = group_id;
388                        }
389                        group_lines.push(li.clone());
390                    }
391                }
392
393                let group = ElevatorGroup::new(group_id, gc.name.clone(), group_lines);
394                groups.push(group);
395
396                // GroupConfig strategy; builder overrides applied after this loop.
397                let dispatch: Box<dyn DispatchStrategy> = gc
398                    .dispatch
399                    .instantiate()
400                    .unwrap_or_else(|| Box::new(crate::dispatch::scan::ScanDispatch::new()));
401                dispatchers.insert(group_id, dispatch);
402                strategy_ids.insert(group_id, gc.dispatch.clone());
403            }
404        } else {
405            // No explicit groups — create a single default group with all lines.
406            let group_id = GroupId(0);
407            let mut group_lines = Vec::new();
408
409            for (line_eid, li) in line_map.values() {
410                if let Some(line_comp) = world.line_mut(*line_eid) {
411                    line_comp.group = group_id;
412                }
413                group_lines.push(li.clone());
414            }
415
416            let group = ElevatorGroup::new(group_id, "Default".into(), group_lines);
417            groups.push(group);
418
419            let dispatch: Box<dyn DispatchStrategy> =
420                Box::new(crate::dispatch::scan::ScanDispatch::new());
421            dispatchers.insert(group_id, dispatch);
422            strategy_ids.insert(group_id, BuiltinStrategy::Scan);
423        }
424
425        // Override with builder-provided dispatchers (they take precedence).
426        for (gid, d) in builder_dispatchers {
427            dispatchers.insert(gid, d);
428        }
429
430        (groups, dispatchers, strategy_ids)
431    }
432
433    /// Restore a simulation from pre-built parts (used by snapshot restore).
434    #[allow(clippy::too_many_arguments)]
435    pub(crate) fn from_parts(
436        world: World,
437        tick: u64,
438        dt: f64,
439        groups: Vec<ElevatorGroup>,
440        stop_lookup: HashMap<StopId, EntityId>,
441        dispatchers: BTreeMap<GroupId, Box<dyn DispatchStrategy>>,
442        strategy_ids: BTreeMap<GroupId, crate::dispatch::BuiltinStrategy>,
443        metrics: Metrics,
444        ticks_per_second: f64,
445    ) -> Self {
446        let mut rider_index = RiderIndex::default();
447        rider_index.rebuild(&world);
448        Self {
449            world,
450            events: EventBus::default(),
451            pending_output: Vec::new(),
452            tick,
453            dt,
454            groups,
455            stop_lookup,
456            dispatchers,
457            strategy_ids,
458            repositioners: BTreeMap::new(),
459            reposition_ids: BTreeMap::new(),
460            metrics,
461            time: TimeAdapter::new(ticks_per_second),
462            hooks: PhaseHooks::default(),
463            elevator_ids_buf: Vec::new(),
464            topo_graph: Mutex::new(TopologyGraph::new()),
465            rider_index,
466        }
467    }
468
469    /// Validate configuration before constructing the simulation.
470    pub(crate) fn validate_config(config: &SimConfig) -> Result<(), SimError> {
471        if config.building.stops.is_empty() {
472            return Err(SimError::InvalidConfig {
473                field: "building.stops",
474                reason: "at least one stop is required".into(),
475            });
476        }
477
478        // Check for duplicate stop IDs.
479        let mut seen_ids = HashSet::new();
480        for stop in &config.building.stops {
481            if !seen_ids.insert(stop.id) {
482                return Err(SimError::InvalidConfig {
483                    field: "building.stops",
484                    reason: format!("duplicate {}", stop.id),
485                });
486            }
487        }
488
489        let stop_ids: HashSet<StopId> = config.building.stops.iter().map(|s| s.id).collect();
490
491        if let Some(line_configs) = &config.building.lines {
492            // ── Explicit topology validation ──
493            Self::validate_explicit_topology(line_configs, &stop_ids, &config.building)?;
494        } else {
495            // ── Legacy flat elevator list validation ──
496            Self::validate_legacy_elevators(&config.elevators, &config.building)?;
497        }
498
499        if config.simulation.ticks_per_second <= 0.0 {
500            return Err(SimError::InvalidConfig {
501                field: "simulation.ticks_per_second",
502                reason: format!(
503                    "must be positive, got {}",
504                    config.simulation.ticks_per_second
505                ),
506            });
507        }
508
509        Ok(())
510    }
511
512    /// Validate the legacy flat elevator list.
513    fn validate_legacy_elevators(
514        elevators: &[crate::config::ElevatorConfig],
515        building: &crate::config::BuildingConfig,
516    ) -> Result<(), SimError> {
517        if elevators.is_empty() {
518            return Err(SimError::InvalidConfig {
519                field: "elevators",
520                reason: "at least one elevator is required".into(),
521            });
522        }
523
524        for elev in elevators {
525            Self::validate_elevator_config(elev, building)?;
526        }
527
528        Ok(())
529    }
530
531    /// Validate a single elevator config's physics and starting stop.
532    fn validate_elevator_config(
533        elev: &crate::config::ElevatorConfig,
534        building: &crate::config::BuildingConfig,
535    ) -> Result<(), SimError> {
536        if elev.max_speed <= 0.0 {
537            return Err(SimError::InvalidConfig {
538                field: "elevators.max_speed",
539                reason: format!("must be positive, got {}", elev.max_speed),
540            });
541        }
542        if elev.acceleration <= 0.0 {
543            return Err(SimError::InvalidConfig {
544                field: "elevators.acceleration",
545                reason: format!("must be positive, got {}", elev.acceleration),
546            });
547        }
548        if elev.deceleration <= 0.0 {
549            return Err(SimError::InvalidConfig {
550                field: "elevators.deceleration",
551                reason: format!("must be positive, got {}", elev.deceleration),
552            });
553        }
554        if elev.weight_capacity <= 0.0 {
555            return Err(SimError::InvalidConfig {
556                field: "elevators.weight_capacity",
557                reason: format!("must be positive, got {}", elev.weight_capacity),
558            });
559        }
560        if elev.inspection_speed_factor <= 0.0 {
561            return Err(SimError::InvalidConfig {
562                field: "elevators.inspection_speed_factor",
563                reason: format!("must be positive, got {}", elev.inspection_speed_factor),
564            });
565        }
566        if !building.stops.iter().any(|s| s.id == elev.starting_stop) {
567            return Err(SimError::InvalidConfig {
568                field: "elevators.starting_stop",
569                reason: format!("references non-existent {}", elev.starting_stop),
570            });
571        }
572        Ok(())
573    }
574
575    /// Validate explicit line/group topology.
576    fn validate_explicit_topology(
577        line_configs: &[crate::config::LineConfig],
578        stop_ids: &HashSet<StopId>,
579        building: &crate::config::BuildingConfig,
580    ) -> Result<(), SimError> {
581        // No duplicate line IDs.
582        let mut seen_line_ids = HashSet::new();
583        for lc in line_configs {
584            if !seen_line_ids.insert(lc.id) {
585                return Err(SimError::InvalidConfig {
586                    field: "building.lines",
587                    reason: format!("duplicate line id {}", lc.id),
588                });
589            }
590        }
591
592        // Every line's serves must reference existing stops.
593        for lc in line_configs {
594            for sid in &lc.serves {
595                if !stop_ids.contains(sid) {
596                    return Err(SimError::InvalidConfig {
597                        field: "building.lines.serves",
598                        reason: format!("line {} references non-existent {}", lc.id, sid),
599                    });
600                }
601            }
602            // Validate elevators within each line.
603            for ec in &lc.elevators {
604                Self::validate_elevator_config(ec, building)?;
605            }
606
607            // Validate max_cars is not exceeded.
608            if let Some(max) = lc.max_cars
609                && lc.elevators.len() > max
610            {
611                return Err(SimError::InvalidConfig {
612                    field: "building.lines.max_cars",
613                    reason: format!(
614                        "line {} has {} elevators but max_cars is {max}",
615                        lc.id,
616                        lc.elevators.len()
617                    ),
618                });
619            }
620        }
621
622        // At least one line with at least one elevator.
623        let has_elevator = line_configs.iter().any(|lc| !lc.elevators.is_empty());
624        if !has_elevator {
625            return Err(SimError::InvalidConfig {
626                field: "building.lines",
627                reason: "at least one line must have at least one elevator".into(),
628            });
629        }
630
631        // No orphaned stops: every stop must be served by at least one line.
632        let served: HashSet<StopId> = line_configs
633            .iter()
634            .flat_map(|lc| lc.serves.iter().copied())
635            .collect();
636        for sid in stop_ids {
637            if !served.contains(sid) {
638                return Err(SimError::InvalidConfig {
639                    field: "building.lines",
640                    reason: format!("orphaned stop {sid} not served by any line"),
641                });
642            }
643        }
644
645        // Validate groups if present.
646        if let Some(group_configs) = &building.groups {
647            let line_id_set: HashSet<u32> = line_configs.iter().map(|lc| lc.id).collect();
648
649            let mut seen_group_ids = HashSet::new();
650            for gc in group_configs {
651                if !seen_group_ids.insert(gc.id) {
652                    return Err(SimError::InvalidConfig {
653                        field: "building.groups",
654                        reason: format!("duplicate group id {}", gc.id),
655                    });
656                }
657                for &lid in &gc.lines {
658                    if !line_id_set.contains(&lid) {
659                        return Err(SimError::InvalidConfig {
660                            field: "building.groups.lines",
661                            reason: format!(
662                                "group {} references non-existent line id {}",
663                                gc.id, lid
664                            ),
665                        });
666                    }
667                }
668            }
669
670            // Check for orphaned lines (not referenced by any group).
671            let referenced_line_ids: HashSet<u32> = group_configs
672                .iter()
673                .flat_map(|g| g.lines.iter().copied())
674                .collect();
675            for lc in line_configs {
676                if !referenced_line_ids.contains(&lc.id) {
677                    return Err(SimError::InvalidConfig {
678                        field: "building.lines",
679                        reason: format!("line {} is not assigned to any group", lc.id),
680                    });
681                }
682            }
683        }
684
685        Ok(())
686    }
687
688    // ── Dispatch management ──────────────────────────────────────────
689
690    /// Replace the dispatch strategy for a group.
691    ///
692    /// The `id` parameter identifies the strategy for snapshot serialization.
693    /// Use `BuiltinStrategy::Custom("name")` for custom strategies.
694    pub fn set_dispatch(
695        &mut self,
696        group: GroupId,
697        strategy: Box<dyn DispatchStrategy>,
698        id: crate::dispatch::BuiltinStrategy,
699    ) {
700        self.dispatchers.insert(group, strategy);
701        self.strategy_ids.insert(group, id);
702    }
703
704    // ── Reposition management ─────────────────────────────────────────
705
706    /// Set the reposition strategy for a group.
707    ///
708    /// Enables the reposition phase for this group. Idle elevators will
709    /// be repositioned according to the strategy after each dispatch phase.
710    pub fn set_reposition(
711        &mut self,
712        group: GroupId,
713        strategy: Box<dyn RepositionStrategy>,
714        id: BuiltinReposition,
715    ) {
716        self.repositioners.insert(group, strategy);
717        self.reposition_ids.insert(group, id);
718    }
719
720    /// Remove the reposition strategy for a group, disabling repositioning.
721    pub fn remove_reposition(&mut self, group: GroupId) {
722        self.repositioners.remove(&group);
723        self.reposition_ids.remove(&group);
724    }
725
726    /// Get the reposition strategy identifier for a group.
727    #[must_use]
728    pub fn reposition_id(&self, group: GroupId) -> Option<&BuiltinReposition> {
729        self.reposition_ids.get(&group)
730    }
731
732    // ── Hooks ────────────────────────────────────────────────────────
733
734    /// Register a hook to run before a simulation phase.
735    ///
736    /// Hooks are called in registration order. The hook receives mutable
737    /// access to the world, allowing entity inspection or modification.
738    pub fn add_before_hook(
739        &mut self,
740        phase: Phase,
741        hook: impl Fn(&mut World) + Send + Sync + 'static,
742    ) {
743        self.hooks.add_before(phase, Box::new(hook));
744    }
745
746    /// Register a hook to run after a simulation phase.
747    ///
748    /// Hooks are called in registration order. The hook receives mutable
749    /// access to the world, allowing entity inspection or modification.
750    pub fn add_after_hook(
751        &mut self,
752        phase: Phase,
753        hook: impl Fn(&mut World) + Send + Sync + 'static,
754    ) {
755        self.hooks.add_after(phase, Box::new(hook));
756    }
757
758    /// Register a hook to run before a phase for a specific group.
759    pub fn add_before_group_hook(
760        &mut self,
761        phase: Phase,
762        group: GroupId,
763        hook: impl Fn(&mut World) + Send + Sync + 'static,
764    ) {
765        self.hooks.add_before_group(phase, group, Box::new(hook));
766    }
767
768    /// Register a hook to run after a phase for a specific group.
769    pub fn add_after_group_hook(
770        &mut self,
771        phase: Phase,
772        group: GroupId,
773        hook: impl Fn(&mut World) + Send + Sync + 'static,
774    ) {
775        self.hooks.add_after_group(phase, group, Box::new(hook));
776    }
777}