import type { UnlockDef, UnlockState } from "../game/unlocks.js";
export interface TechNodeDef extends UnlockDef {
    requires?: readonly string[];
    cost?: Readonly<Record<string, number>>;
    grants?: readonly string[];
    recipe?: string;
}
export type TechState = UnlockState;
export type TechRejection = {
    reason: "unknown-node";
} | {
    reason: "already-unlocked";
} | {
    reason: "missing-prerequisites";
    missing: readonly string[];
};
export type TechCheck = {
    ok: true;
} | ({
    ok: false;
} & TechRejection);
/** @internal */
export declare function techPrerequisitesMet(state: TechState, node: TechNodeDef): boolean;
/** @internal */
export declare function missingPrerequisites(state: TechState, node: TechNodeDef): string[];
/** @internal */
export declare function canUnlockTech(defs: readonly TechNodeDef[], state: TechState, id: string): TechCheck;
/** @internal */
export declare function grantTech(state: TechState, node: TechNodeDef): string[];
/**
 * Research/tech nodes gated by prerequisites that unlock recipes and capabilities as they are granted.
 *
 * @capability tech-tree research nodes with prerequisites that unlock recipes
  * @internal
  */
export declare function availableTech(defs: readonly TechNodeDef[], state: TechState): TechNodeDef[];
/** @internal */
export declare function unlockedRecipes(defs: readonly TechNodeDef[], state: TechState): string[];
export interface TechTree {
    has(userId: string, id: string): boolean;
    canUnlock(userId: string, id: string): TechCheck;
    unlock(userId: string, id: string): TechCheck;
    available(userId: string): TechNodeDef[];
    recipes(userId: string): string[];
    list(userId: string): string[];
    tree(categoryId: string): UnlockDef[];
    node(id: string): TechNodeDef | null;
    snapshot(userId: string): string[];
    hydrate(userId: string, ids: string[]): void;
}
/** @internal */
export declare function createTechTree(defs?: readonly TechNodeDef[]): TechTree;