feat: version 2 beta

libraries/queue.ts

@@ -0,0 +1,100 @@
+export class Queue<T> {
+  status: Status;
+
+  #queue: Message<T>[];
+  #handle: Handler<T>;
+  #hooks: Hooks;
+
+  constructor(handler: Handler<T>, hooks: Hooks = {}) {
+    this.status = "idle";
+    this.#queue = [];
+    this.#handle = handler;
+    this.#hooks = hooks;
+  }
+
+  /*
+   |--------------------------------------------------------------------------------
+   | Utilities
+   |--------------------------------------------------------------------------------
+   */
+
+  is(status: Status): boolean {
+    return this.status === status;
+  }
+
+  push(message: T, resolve: MessagePromise["resolve"], reject: MessagePromise["reject"]): this {
+    this.#queue.push({ message, resolve, reject });
+    this.#process();
+    return this;
+  }
+
+  flush(filter?: Filter<Message<T>>): this {
+    if (filter) {
+      this.#queue = this.#queue.filter(filter);
+    } else {
+      this.#queue = [];
+    }
+    return this;
+  }
+
+  /*
+   |--------------------------------------------------------------------------------
+   | Processor
+   |--------------------------------------------------------------------------------
+   */
+
+  async #process(): Promise<this> {
+    if (this.is("working")) {
+      return this;
+    }
+
+    this.#setStatus("working");
+
+    const job = this.#queue.shift();
+    if (!job) {
+      return this.#setStatus("drained");
+    }
+
+    this.#handle(job.message)
+      .then(job.resolve)
+      .catch(job.reject)
+      .finally(() => {
+        this.#setStatus("idle").#process();
+      });
+
+    return this;
+  }
+
+  #setStatus(value: Status): this {
+    this.status = value;
+    if (value === "drained") {
+      this.#hooks.onDrained?.();
+    }
+    return this;
+  }
+}
+
+/*
+ |--------------------------------------------------------------------------------
+ | Types
+ |--------------------------------------------------------------------------------
+ */
+
+type Status = "idle" | "working" | "drained";
+
+type Handler<T> = (message: T) => Promise<any> | Promise<any[]>;
+
+type Hooks = {
+  onDrained?: () => void;
+};
+
+type Message<T> = {
+  message: T;
+} & MessagePromise;
+
+type MessagePromise = {
+  resolve: (value: any) => void;
+  reject: (reason?: any) => void;
+};
+
+type Filter<T> = (job: T) => boolean;