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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                door_command_queue: Vec::new(),
223                manual_target_velocity: None,
224            },
225        );
226        #[cfg(feature = "energy")]
227        if let Some(ref profile) = ec.energy_profile {
228            world.set_energy_profile(eid, profile.clone());
229            world.set_energy_metrics(eid, crate::energy::EnergyMetrics::default());
230        }
231        if let Some(mode) = ec.service_mode {
232            world.set_service_mode(eid, mode);
233        }
234        world.set_destination_queue(eid, crate::components::DestinationQueue::new());
235        eid
236    }
237
238    /// Build topology from the legacy flat elevator list (single default line + group).
239    fn build_legacy_topology(
240        world: &mut World,
241        config: &SimConfig,
242        stop_lookup: &HashMap<StopId, EntityId>,
243        builder_dispatchers: BTreeMap<GroupId, Box<dyn DispatchStrategy>>,
244    ) -> TopologyResult {
245        let all_stop_entities: Vec<EntityId> = stop_lookup.values().copied().collect();
246        let stop_positions: Vec<f64> = config.building.stops.iter().map(|s| s.position).collect();
247        let min_pos = stop_positions.iter().copied().fold(f64::INFINITY, f64::min);
248        let max_pos = stop_positions
249            .iter()
250            .copied()
251            .fold(f64::NEG_INFINITY, f64::max);
252
253        let default_line_eid = world.spawn();
254        world.set_line(
255            default_line_eid,
256            Line {
257                name: "Default".into(),
258                group: GroupId(0),
259                orientation: Orientation::Vertical,
260                position: None,
261                min_position: min_pos,
262                max_position: max_pos,
263                max_cars: None,
264            },
265        );
266
267        let mut elevator_entities = Vec::new();
268        for ec in &config.elevators {
269            let eid = Self::spawn_elevator_entity(
270                world,
271                ec,
272                default_line_eid,
273                stop_lookup,
274                &config.building.stops,
275            );
276            elevator_entities.push(eid);
277        }
278
279        let default_line_info =
280            LineInfo::new(default_line_eid, elevator_entities, all_stop_entities);
281
282        let group = ElevatorGroup::new(GroupId(0), "Default".into(), vec![default_line_info]);
283
284        // Use builder-provided dispatcher or default Scan.
285        let mut dispatchers = BTreeMap::new();
286        let dispatch = builder_dispatchers.into_iter().next().map_or_else(
287            || Box::new(crate::dispatch::scan::ScanDispatch::new()) as Box<dyn DispatchStrategy>,
288            |(_, d)| d,
289        );
290        dispatchers.insert(GroupId(0), dispatch);
291
292        let mut strategy_ids = BTreeMap::new();
293        strategy_ids.insert(GroupId(0), BuiltinStrategy::Scan);
294
295        (vec![group], dispatchers, strategy_ids)
296    }
297
298    /// Build topology from explicit `LineConfig`/`GroupConfig` definitions.
299    #[allow(clippy::too_many_lines)]
300    fn build_explicit_topology(
301        world: &mut World,
302        config: &SimConfig,
303        line_configs: &[crate::config::LineConfig],
304        stop_lookup: &HashMap<StopId, EntityId>,
305        builder_dispatchers: BTreeMap<GroupId, Box<dyn DispatchStrategy>>,
306    ) -> TopologyResult {
307        // Map line config id → (line EntityId, LineInfo).
308        let mut line_map: HashMap<u32, (EntityId, LineInfo)> = HashMap::new();
309
310        for lc in line_configs {
311            // Resolve served stop entities.
312            let served_entities: Vec<EntityId> = lc
313                .serves
314                .iter()
315                .filter_map(|sid| stop_lookup.get(sid).copied())
316                .collect();
317
318            // Compute min/max from stops if not explicitly set.
319            let stop_positions: Vec<f64> = lc
320                .serves
321                .iter()
322                .filter_map(|sid| {
323                    config
324                        .building
325                        .stops
326                        .iter()
327                        .find(|s| s.id == *sid)
328                        .map(|s| s.position)
329                })
330                .collect();
331            let auto_min = stop_positions.iter().copied().fold(f64::INFINITY, f64::min);
332            let auto_max = stop_positions
333                .iter()
334                .copied()
335                .fold(f64::NEG_INFINITY, f64::max);
336
337            let min_pos = lc.min_position.unwrap_or(auto_min);
338            let max_pos = lc.max_position.unwrap_or(auto_max);
339
340            let line_eid = world.spawn();
341            // The group assignment will be set when we process GroupConfigs.
342            // Default to GroupId(0) initially.
343            world.set_line(
344                line_eid,
345                Line {
346                    name: lc.name.clone(),
347                    group: GroupId(0),
348                    orientation: lc.orientation,
349                    position: lc.position,
350                    min_position: min_pos,
351                    max_position: max_pos,
352                    max_cars: lc.max_cars,
353                },
354            );
355
356            // Spawn elevators for this line.
357            let mut elevator_entities = Vec::new();
358            for ec in &lc.elevators {
359                let eid = Self::spawn_elevator_entity(
360                    world,
361                    ec,
362                    line_eid,
363                    stop_lookup,
364                    &config.building.stops,
365                );
366                elevator_entities.push(eid);
367            }
368
369            let line_info = LineInfo::new(line_eid, elevator_entities, served_entities);
370            line_map.insert(lc.id, (line_eid, line_info));
371        }
372
373        // Build groups from GroupConfigs, or auto-infer a single group.
374        let group_configs = config.building.groups.as_deref();
375        let mut groups = Vec::new();
376        let mut dispatchers = BTreeMap::new();
377        let mut strategy_ids = BTreeMap::new();
378
379        if let Some(gcs) = group_configs {
380            for gc in gcs {
381                let group_id = GroupId(gc.id);
382
383                let mut group_lines = Vec::new();
384
385                for &lid in &gc.lines {
386                    if let Some((line_eid, li)) = line_map.get(&lid) {
387                        // Update the line's group assignment.
388                        if let Some(line_comp) = world.line_mut(*line_eid) {
389                            line_comp.group = group_id;
390                        }
391                        group_lines.push(li.clone());
392                    }
393                }
394
395                let group = ElevatorGroup::new(group_id, gc.name.clone(), group_lines);
396                groups.push(group);
397
398                // GroupConfig strategy; builder overrides applied after this loop.
399                let dispatch: Box<dyn DispatchStrategy> = gc
400                    .dispatch
401                    .instantiate()
402                    .unwrap_or_else(|| Box::new(crate::dispatch::scan::ScanDispatch::new()));
403                dispatchers.insert(group_id, dispatch);
404                strategy_ids.insert(group_id, gc.dispatch.clone());
405            }
406        } else {
407            // No explicit groups — create a single default group with all lines.
408            let group_id = GroupId(0);
409            let mut group_lines = Vec::new();
410
411            for (line_eid, li) in line_map.values() {
412                if let Some(line_comp) = world.line_mut(*line_eid) {
413                    line_comp.group = group_id;
414                }
415                group_lines.push(li.clone());
416            }
417
418            let group = ElevatorGroup::new(group_id, "Default".into(), group_lines);
419            groups.push(group);
420
421            let dispatch: Box<dyn DispatchStrategy> =
422                Box::new(crate::dispatch::scan::ScanDispatch::new());
423            dispatchers.insert(group_id, dispatch);
424            strategy_ids.insert(group_id, BuiltinStrategy::Scan);
425        }
426
427        // Override with builder-provided dispatchers (they take precedence).
428        for (gid, d) in builder_dispatchers {
429            dispatchers.insert(gid, d);
430        }
431
432        (groups, dispatchers, strategy_ids)
433    }
434
435    /// Restore a simulation from pre-built parts (used by snapshot restore).
436    #[allow(clippy::too_many_arguments)]
437    pub(crate) fn from_parts(
438        world: World,
439        tick: u64,
440        dt: f64,
441        groups: Vec<ElevatorGroup>,
442        stop_lookup: HashMap<StopId, EntityId>,
443        dispatchers: BTreeMap<GroupId, Box<dyn DispatchStrategy>>,
444        strategy_ids: BTreeMap<GroupId, crate::dispatch::BuiltinStrategy>,
445        metrics: Metrics,
446        ticks_per_second: f64,
447    ) -> Self {
448        let mut rider_index = RiderIndex::default();
449        rider_index.rebuild(&world);
450        Self {
451            world,
452            events: EventBus::default(),
453            pending_output: Vec::new(),
454            tick,
455            dt,
456            groups,
457            stop_lookup,
458            dispatchers,
459            strategy_ids,
460            repositioners: BTreeMap::new(),
461            reposition_ids: BTreeMap::new(),
462            metrics,
463            time: TimeAdapter::new(ticks_per_second),
464            hooks: PhaseHooks::default(),
465            elevator_ids_buf: Vec::new(),
466            topo_graph: Mutex::new(TopologyGraph::new()),
467            rider_index,
468        }
469    }
470
471    /// Validate configuration before constructing the simulation.
472    pub(crate) fn validate_config(config: &SimConfig) -> Result<(), SimError> {
473        if config.building.stops.is_empty() {
474            return Err(SimError::InvalidConfig {
475                field: "building.stops",
476                reason: "at least one stop is required".into(),
477            });
478        }
479
480        // Check for duplicate stop IDs.
481        let mut seen_ids = HashSet::new();
482        for stop in &config.building.stops {
483            if !seen_ids.insert(stop.id) {
484                return Err(SimError::InvalidConfig {
485                    field: "building.stops",
486                    reason: format!("duplicate {}", stop.id),
487                });
488            }
489        }
490
491        let stop_ids: HashSet<StopId> = config.building.stops.iter().map(|s| s.id).collect();
492
493        if let Some(line_configs) = &config.building.lines {
494            // ── Explicit topology validation ──
495            Self::validate_explicit_topology(line_configs, &stop_ids, &config.building)?;
496        } else {
497            // ── Legacy flat elevator list validation ──
498            Self::validate_legacy_elevators(&config.elevators, &config.building)?;
499        }
500
501        if config.simulation.ticks_per_second <= 0.0 {
502            return Err(SimError::InvalidConfig {
503                field: "simulation.ticks_per_second",
504                reason: format!(
505                    "must be positive, got {}",
506                    config.simulation.ticks_per_second
507                ),
508            });
509        }
510
511        Ok(())
512    }
513
514    /// Validate the legacy flat elevator list.
515    fn validate_legacy_elevators(
516        elevators: &[crate::config::ElevatorConfig],
517        building: &crate::config::BuildingConfig,
518    ) -> Result<(), SimError> {
519        if elevators.is_empty() {
520            return Err(SimError::InvalidConfig {
521                field: "elevators",
522                reason: "at least one elevator is required".into(),
523            });
524        }
525
526        for elev in elevators {
527            Self::validate_elevator_config(elev, building)?;
528        }
529
530        Ok(())
531    }
532
533    /// Validate a single elevator config's physics and starting stop.
534    fn validate_elevator_config(
535        elev: &crate::config::ElevatorConfig,
536        building: &crate::config::BuildingConfig,
537    ) -> Result<(), SimError> {
538        if elev.max_speed <= 0.0 {
539            return Err(SimError::InvalidConfig {
540                field: "elevators.max_speed",
541                reason: format!("must be positive, got {}", elev.max_speed),
542            });
543        }
544        if elev.acceleration <= 0.0 {
545            return Err(SimError::InvalidConfig {
546                field: "elevators.acceleration",
547                reason: format!("must be positive, got {}", elev.acceleration),
548            });
549        }
550        if elev.deceleration <= 0.0 {
551            return Err(SimError::InvalidConfig {
552                field: "elevators.deceleration",
553                reason: format!("must be positive, got {}", elev.deceleration),
554            });
555        }
556        if elev.weight_capacity <= 0.0 {
557            return Err(SimError::InvalidConfig {
558                field: "elevators.weight_capacity",
559                reason: format!("must be positive, got {}", elev.weight_capacity),
560            });
561        }
562        if elev.inspection_speed_factor <= 0.0 {
563            return Err(SimError::InvalidConfig {
564                field: "elevators.inspection_speed_factor",
565                reason: format!("must be positive, got {}", elev.inspection_speed_factor),
566            });
567        }
568        if !building.stops.iter().any(|s| s.id == elev.starting_stop) {
569            return Err(SimError::InvalidConfig {
570                field: "elevators.starting_stop",
571                reason: format!("references non-existent {}", elev.starting_stop),
572            });
573        }
574        Ok(())
575    }
576
577    /// Validate explicit line/group topology.
578    fn validate_explicit_topology(
579        line_configs: &[crate::config::LineConfig],
580        stop_ids: &HashSet<StopId>,
581        building: &crate::config::BuildingConfig,
582    ) -> Result<(), SimError> {
583        // No duplicate line IDs.
584        let mut seen_line_ids = HashSet::new();
585        for lc in line_configs {
586            if !seen_line_ids.insert(lc.id) {
587                return Err(SimError::InvalidConfig {
588                    field: "building.lines",
589                    reason: format!("duplicate line id {}", lc.id),
590                });
591            }
592        }
593
594        // Every line's serves must reference existing stops.
595        for lc in line_configs {
596            for sid in &lc.serves {
597                if !stop_ids.contains(sid) {
598                    return Err(SimError::InvalidConfig {
599                        field: "building.lines.serves",
600                        reason: format!("line {} references non-existent {}", lc.id, sid),
601                    });
602                }
603            }
604            // Validate elevators within each line.
605            for ec in &lc.elevators {
606                Self::validate_elevator_config(ec, building)?;
607            }
608
609            // Validate max_cars is not exceeded.
610            if let Some(max) = lc.max_cars
611                && lc.elevators.len() > max
612            {
613                return Err(SimError::InvalidConfig {
614                    field: "building.lines.max_cars",
615                    reason: format!(
616                        "line {} has {} elevators but max_cars is {max}",
617                        lc.id,
618                        lc.elevators.len()
619                    ),
620                });
621            }
622        }
623
624        // At least one line with at least one elevator.
625        let has_elevator = line_configs.iter().any(|lc| !lc.elevators.is_empty());
626        if !has_elevator {
627            return Err(SimError::InvalidConfig {
628                field: "building.lines",
629                reason: "at least one line must have at least one elevator".into(),
630            });
631        }
632
633        // No orphaned stops: every stop must be served by at least one line.
634        let served: HashSet<StopId> = line_configs
635            .iter()
636            .flat_map(|lc| lc.serves.iter().copied())
637            .collect();
638        for sid in stop_ids {
639            if !served.contains(sid) {
640                return Err(SimError::InvalidConfig {
641                    field: "building.lines",
642                    reason: format!("orphaned stop {sid} not served by any line"),
643                });
644            }
645        }
646
647        // Validate groups if present.
648        if let Some(group_configs) = &building.groups {
649            let line_id_set: HashSet<u32> = line_configs.iter().map(|lc| lc.id).collect();
650
651            let mut seen_group_ids = HashSet::new();
652            for gc in group_configs {
653                if !seen_group_ids.insert(gc.id) {
654                    return Err(SimError::InvalidConfig {
655                        field: "building.groups",
656                        reason: format!("duplicate group id {}", gc.id),
657                    });
658                }
659                for &lid in &gc.lines {
660                    if !line_id_set.contains(&lid) {
661                        return Err(SimError::InvalidConfig {
662                            field: "building.groups.lines",
663                            reason: format!(
664                                "group {} references non-existent line id {}",
665                                gc.id, lid
666                            ),
667                        });
668                    }
669                }
670            }
671
672            // Check for orphaned lines (not referenced by any group).
673            let referenced_line_ids: HashSet<u32> = group_configs
674                .iter()
675                .flat_map(|g| g.lines.iter().copied())
676                .collect();
677            for lc in line_configs {
678                if !referenced_line_ids.contains(&lc.id) {
679                    return Err(SimError::InvalidConfig {
680                        field: "building.lines",
681                        reason: format!("line {} is not assigned to any group", lc.id),
682                    });
683                }
684            }
685        }
686
687        Ok(())
688    }
689
690    // ── Dispatch management ──────────────────────────────────────────
691
692    /// Replace the dispatch strategy for a group.
693    ///
694    /// The `id` parameter identifies the strategy for snapshot serialization.
695    /// Use `BuiltinStrategy::Custom("name")` for custom strategies.
696    pub fn set_dispatch(
697        &mut self,
698        group: GroupId,
699        strategy: Box<dyn DispatchStrategy>,
700        id: crate::dispatch::BuiltinStrategy,
701    ) {
702        self.dispatchers.insert(group, strategy);
703        self.strategy_ids.insert(group, id);
704    }
705
706    // ── Reposition management ─────────────────────────────────────────
707
708    /// Set the reposition strategy for a group.
709    ///
710    /// Enables the reposition phase for this group. Idle elevators will
711    /// be repositioned according to the strategy after each dispatch phase.
712    pub fn set_reposition(
713        &mut self,
714        group: GroupId,
715        strategy: Box<dyn RepositionStrategy>,
716        id: BuiltinReposition,
717    ) {
718        self.repositioners.insert(group, strategy);
719        self.reposition_ids.insert(group, id);
720    }
721
722    /// Remove the reposition strategy for a group, disabling repositioning.
723    pub fn remove_reposition(&mut self, group: GroupId) {
724        self.repositioners.remove(&group);
725        self.reposition_ids.remove(&group);
726    }
727
728    /// Get the reposition strategy identifier for a group.
729    #[must_use]
730    pub fn reposition_id(&self, group: GroupId) -> Option<&BuiltinReposition> {
731        self.reposition_ids.get(&group)
732    }
733
734    // ── Hooks ────────────────────────────────────────────────────────
735
736    /// Register a hook to run before a simulation phase.
737    ///
738    /// Hooks are called in registration order. The hook receives mutable
739    /// access to the world, allowing entity inspection or modification.
740    pub fn add_before_hook(
741        &mut self,
742        phase: Phase,
743        hook: impl Fn(&mut World) + Send + Sync + 'static,
744    ) {
745        self.hooks.add_before(phase, Box::new(hook));
746    }
747
748    /// Register a hook to run after a simulation phase.
749    ///
750    /// Hooks are called in registration order. The hook receives mutable
751    /// access to the world, allowing entity inspection or modification.
752    pub fn add_after_hook(
753        &mut self,
754        phase: Phase,
755        hook: impl Fn(&mut World) + Send + Sync + 'static,
756    ) {
757        self.hooks.add_after(phase, Box::new(hook));
758    }
759
760    /// Register a hook to run before a phase for a specific group.
761    pub fn add_before_group_hook(
762        &mut self,
763        phase: Phase,
764        group: GroupId,
765        hook: impl Fn(&mut World) + Send + Sync + 'static,
766    ) {
767        self.hooks.add_before_group(phase, group, Box::new(hook));
768    }
769
770    /// Register a hook to run after a phase for a specific group.
771    pub fn add_after_group_hook(
772        &mut self,
773        phase: Phase,
774        group: GroupId,
775        hook: impl Fn(&mut World) + Send + Sync + 'static,
776    ) {
777        self.hooks.add_after_group(phase, group, Box::new(hook));
778    }
779}