This commit is contained in:
Generated
Vendored
+37
@@ -0,0 +1,37 @@
|
||||
export type FSMLifecycleFn<StatesT extends string, EventsT extends string> = (meta: LifecycleFnMeta<StatesT, EventsT>) => void;
|
||||
export type LifecycleFnMeta<StatesT extends string, EventsT extends string> = {
|
||||
from: StatesT | null;
|
||||
to: StatesT;
|
||||
event: EventsT | null;
|
||||
args: unknown;
|
||||
};
|
||||
export declare function isLifecycleFnMeta<StatesT extends string, EventsT extends string>(meta: unknown): meta is LifecycleFnMeta<StatesT, EventsT>;
|
||||
export type FSMLifecycle = "_enter" | "_exit";
|
||||
export type ActionFn<StatesT> = (...args: unknown[]) => StatesT | void;
|
||||
export type Action<StatesT> = StatesT | ActionFn<StatesT>;
|
||||
export type StateHandler<StatesT extends string, EventsT extends string> = {
|
||||
[e in EventsT]?: Action<StatesT>;
|
||||
} & {
|
||||
[k in FSMLifecycle]?: FSMLifecycleFn<StatesT, EventsT>;
|
||||
};
|
||||
export type Transition<StatesT extends string, EventsT extends string> = {
|
||||
[s in StatesT]: StateHandler<StatesT, EventsT>;
|
||||
} & {
|
||||
"*"?: StateHandler<StatesT, EventsT>;
|
||||
};
|
||||
/**
|
||||
* Defines a strongly-typed finite state machine.
|
||||
*
|
||||
* @see {@link https://runed.dev/docs/utilities/finite-state-machine}
|
||||
*/
|
||||
export declare class FiniteStateMachine<StatesT extends string, EventsT extends string> {
|
||||
#private;
|
||||
readonly states: Transition<StatesT, EventsT>;
|
||||
constructor(initial: StatesT, states: Transition<StatesT, EventsT>);
|
||||
/** Triggers a new event and returns the new state. */
|
||||
send(event: EventsT, ...args: unknown[]): StatesT;
|
||||
/** Debounces the triggering of an event. */
|
||||
debounce(wait: number | undefined, event: EventsT, ...args: unknown[]): Promise<StatesT>;
|
||||
/** The current state. */
|
||||
get current(): StatesT;
|
||||
}
|
||||
Generated
Vendored
+78
@@ -0,0 +1,78 @@
|
||||
export function isLifecycleFnMeta(meta) {
|
||||
return (!!meta &&
|
||||
typeof meta === "object" &&
|
||||
"to" in meta &&
|
||||
"from" in meta &&
|
||||
"event" in meta &&
|
||||
"args" in meta);
|
||||
}
|
||||
/**
|
||||
* Defines a strongly-typed finite state machine.
|
||||
*
|
||||
* @see {@link https://runed.dev/docs/utilities/finite-state-machine}
|
||||
*/
|
||||
export class FiniteStateMachine {
|
||||
#current = $state();
|
||||
states;
|
||||
#timeout = {};
|
||||
constructor(initial, states) {
|
||||
this.#current = initial;
|
||||
this.states = states;
|
||||
this.send = this.send.bind(this);
|
||||
this.debounce = this.debounce.bind(this);
|
||||
// synthetically trigger _enter for the initial state.
|
||||
this.#dispatch("_enter", { from: null, to: initial, event: null, args: [] });
|
||||
}
|
||||
#transition(newState, event, args) {
|
||||
const metadata = { from: this.#current, to: newState, event, args };
|
||||
this.#dispatch("_exit", metadata);
|
||||
this.#current = newState;
|
||||
this.#dispatch("_enter", metadata);
|
||||
}
|
||||
#dispatch(event, ...args) {
|
||||
const action = this.states[this.#current]?.[event] ?? this.states["*"]?.[event];
|
||||
if (action instanceof Function) {
|
||||
if (event === "_enter" || event === "_exit") {
|
||||
if (isLifecycleFnMeta(args[0])) {
|
||||
action(args[0]);
|
||||
}
|
||||
else {
|
||||
console.warn("Invalid metadata passed to lifecycle function of the FSM.");
|
||||
}
|
||||
}
|
||||
else {
|
||||
return action(...args);
|
||||
}
|
||||
}
|
||||
else if (typeof action === "string") {
|
||||
return action;
|
||||
}
|
||||
else if (event !== "_enter" && event !== "_exit") {
|
||||
console.warn("No action defined for event", event, "in state", this.#current);
|
||||
}
|
||||
}
|
||||
/** Triggers a new event and returns the new state. */
|
||||
send(event, ...args) {
|
||||
const newState = this.#dispatch(event, ...args);
|
||||
if (newState && newState !== this.#current) {
|
||||
this.#transition(newState, event, args);
|
||||
}
|
||||
return this.#current;
|
||||
}
|
||||
/** Debounces the triggering of an event. */
|
||||
async debounce(wait = 500, event, ...args) {
|
||||
if (this.#timeout[event]) {
|
||||
clearTimeout(this.#timeout[event]);
|
||||
}
|
||||
return new Promise((resolve) => {
|
||||
this.#timeout[event] = setTimeout(() => {
|
||||
delete this.#timeout[event];
|
||||
resolve(this.send(event, ...args));
|
||||
}, wait);
|
||||
});
|
||||
}
|
||||
/** The current state. */
|
||||
get current() {
|
||||
return this.#current;
|
||||
}
|
||||
}
|
||||
+1
@@ -0,0 +1 @@
|
||||
export * from "./finite-state-machine.svelte.js";
|
||||
+1
@@ -0,0 +1 @@
|
||||
export * from "./finite-state-machine.svelte.js";
|
||||
Reference in New Issue
Block a user