SkillManager

Manages the skill tree (DAG), skill points and the injection of passive modifiers. Accessible via engine.skills.

import { SkillManager } from 'catalyst-engine';

Conceptual guide: Skill tree.

Constructor

new SkillManager(statManager: StatManager, eventBus: EngineEventBus)

Receives by dependency injection the StatManager (to inject the passive modifiers) and the EngineEventBus (to emit STAT_CHANGED). Instantiated automatically by the CatalystEngine.

Properties

Property	Type	Description
skillPoints (getter)	number	Available skill points.

Methods

loadSkillTree()

loadSkillTree(config: ISkillNode[]): void

Loads the tree nodes. Each node is cloned with currentLevel forced to 0.

engine.skills.loadSkillTree(skillTreeJson);

addSkillPoints()

addSkillPoints(points: number): void

Adds spendable skill points. The facade automatically adds 2 of them for each level gained.

getSkill()

getSkill(skillId: string): ISkillNode | undefined

Returns the skill node, or undefined if it does not exist.

upgradeSkill()

upgradeSkill(skillId: string, playerLevel: number): ISkillUnlockResult

Attempts to upgrade the skill by one level. It runs the checks in order and returns an ISkillUnlockResult. On success: it deducts the points, increments currentLevel, injects/updates the passive modifiers (for PASSIVE skills) and emits STAT_CHANGED.

Failure reason	Cause
NOT_FOUND	skill does not exist
MAX_LEVEL	already at maximum level
NO_POINTS	not enough points
LOW_LEVEL	player level too low
MISSING_PREREQUISITES	prerequisite not unlocked

const res = engine.skills.upgradeSkill('brute_force', engine.exp.currentLevel);
if (!res.success) console.log(res.reason);

exportState()

exportState(): { unspentPoints: number; unlockedSkills: Record<string, number> }

Exports unspent points and unlocked skills (id → level), including only those with currentLevel > 0. Used by save().

importState()

importState(state: { unspentPoints: number; unlockedSkills: Record<string, number> }): void

Restores skill points and levels, first resetting the entire tree, and re-injects the passive modifiers into the stats. Used by load().