extends Node
## Pure signal hub — notification-only, no state, no callbacks back into singletons.
##
## Subsystems mutate themselves; this bus only spreads the news. Add signals as
## features land — keep this file readable. See docs/architecture.md.

# Sim
signal sim_tick(tick_number: int)    ## Emitted once per sim tick at the current speed.
signal speed_changed(new_speed: int) ## Emitted when Sim.current_speed changes; value is Speed enum cast to int.

# Phase 2 will add pawn-state signals (selected, deselected, walking, …).

# Phase 5 — Designation paint mode.
signal designation_added(cell: Vector2i, tool: StringName)   ## Ghost placed + job queued.
signal designation_cleared(cell: Vector2i)                   ## Ghost removed (job cancelled).

# Phase 8 — Mood system.
signal pawn_mood_changed(pawn, mood: float)  ## Emitted by Pawn._recompute_mood() whenever mood is recalculated.

# Phase 9 — HP + Status system.
signal pawn_took_damage(pawn, amount: float)   ## Emitted by Pawn.take_damage() after HP is reduced.
signal pawn_status_added(pawn, status)         ## Emitted by Pawn.add_status() when a new status is appended.
signal pawn_status_removed(pawn, status)       ## Emitted by Pawn.remove_status_by_id() when a status is dropped.

# Phase 12 — Seasons + Weather.
signal season_changed(season: StringName)      ## Emitted by Clock when current_season() rolls over (Spring → Summer → Autumn → Winter).
signal weather_changed(weather: StringName)    ## Emitted by Weather autoload when the daily roll resolves to a new weather kind.

# Phase 13 — Rooms + Roofing + Beauty + Dirtiness + Cleaning.
signal room_changed(room_id: int)              ## Emitted when a room is created, destroyed, or recomputed (id may be invalid post-destroy).
signal room_too_large(top_left: Vector2i, cell_count: int) ## Emitted when BFS hits ROOM_MAX_CELLS — surfaces the "split with interior wall" banner.
signal tile_beauty_changed(tile: Vector2i, beauty: float)  ## Emitted when beauty recomputes for a tile (Phase 13 beauty system).
signal tile_dirtiness_changed(tile: Vector2i, dirt: float) ## Emitted when dirtiness crosses a tier threshold (clean/dirty/filthy).

# Phase 14 — Death + corpses + burial.
signal pawn_arrived_at_destination(pawn, tile: Vector2i) ## Emitted by Pawn when a walk-toil completes. DirtinessSystem uses this for traffic-dirt bumps.
signal pawn_died(pawn, cause: StringName)          ## Emitted right before Pawn is unregistered; corpse spawn handler listens here.
signal corpse_spawned(corpse)                      ## Emitted when a Corpse entity is added to the world (right after pawn_died handler).
signal corpse_buried(corpse, grave_marker)         ## Emitted when a corpse reaches a GraveSlot and converts to a permanent GraveMarker.
signal corpse_cremated(corpse, pyre)               ## Emitted when a corpse is consumed by a cremation pyre recipe.
signal corpse_rotted_away(corpse)                  ## Emitted when an un-handled corpse hits decay 100 and is destroyed.

# Phase 15 — Storyteller.
signal storyteller_event_fired(event)              ## Emitted when Storyteller selects an event and is about to display it (carries EventDef).
signal storyteller_event_resolved(event, choice_index: int) ## Emitted after the player dismisses or chooses (choice 0 = dismiss/first option).
signal storyteller_tension_changed(tension: float) ## Emitted when running tension score changes (0..100).
signal storyteller_ghost_state_entered                ## Emitted when all colonists are dead/gone — wanderer recovery clock starts.
signal storyteller_ghost_state_exited                ## Emitted when a wanderer joins and the colony is alive again.

# Phase 16 — Save/load.
signal save_started(slot: StringName)              ## Emitted by SaveSystem.write_save before file IO.
signal save_finished(slot: StringName, ok: bool)   ## Emitted after file IO; ok=false on write failure.
signal load_started(slot: StringName)              ## Emitted by SaveSystem.apply_save before clear_all.
signal load_finished(slot: StringName, ok: bool, real_seconds_away: int) ## Emitted after respawn; real_seconds_away drives the "you've been away X" toast.

# Phase 17 — Touch UX completion.
signal pawn_selected(pawn)                         ## Emitted when Selection picks a pawn — opens PawnDetailPanel.
signal pawn_deselected                             ## Emitted when Selection clears — closes PawnDetailPanel.
signal workbench_selected(workbench)
signal workbench_deselected
signal stockpile_selected(zone)                    ## Emitted when Selection picks a StockpileZone — opens StockpilePanel for filter editing.
signal stockpile_deselected                        ## Emitted when Selection clears the active stockpile.
signal pawn_priority_changed(pawn, category: StringName, level: int) ## Emitted when priority matrix updates a cell.
signal alert_added(severity: StringName, text: String, focus_tile: Vector2i) ## Emitted by gameplay subsystems to surface a player notice. severity = info | warn | danger.
signal request_wolf_spawn(count: int)              ## Phase 15 EventCatalog → WolfSpawner. Decouples threat-event effects from spawner.
signal wolf_spawned(wolves: Array)                 ## Emitted by WolfSpawner AFTER a raid wave has been instantiated; carries the spawned Wolf nodes. Audio uses this for raid-warning sting.
signal request_pawn_spawn(skills: Dictionary)      ## Phase 17 EventCatalog wanderer events → World scene. skills dict is forwarded to pawn.setup; empty dict = random skills.
signal day_ended(summary: Dictionary)              ## Emitted by Clock at dusk→night boundary; carries the end-of-day recap dict.

# Phase 19 — Onboarding (hint system + help section).
signal help_requested                              ## Settings "Help" button → opens HelpModal.
signal hint_dismissed(hint_id: StringName)         ## Emitted by HintOverlay when player closes a hint; HintSystem persists the dismissal.
signal ui_panel_opened(panel_id: StringName)       ## Emitted by UI panels (build_drawer, work_matrix, ...) when they become visible. HintSystem subscribes for tour gating.

# Accessibility (Phase 19 completion).
signal settings_changed                            ## Emitted by SettingsMenu._on_save_pressed() after GameState.apply_settings(); UI panels that honour accessibility flags re-read them here.

# Phase 18 — Alert wiring (dangling signals surfaced to AlertsLog).
signal no_stockpile_accepts(item_type: StringName, tile: Vector2i) ## Emitted by HaulingProvider when an item needs haul but no stockpile accepts it (rate-limited per item_type).
signal stockpile_layout_changed                                    ## Emitted when any stockpile is added, removed, or has its filter/priority edited. HaulingProvider listens to reset haul_rejected items.
signal bill_blocked(recipe_label: String, reason: StringName, focus_tile: Vector2i) ## Emitted by CraftingProvider when a bill cannot proceed. reason: missing_ingredient | skill_too_low | no_workbench.
