From dd2767fe8f1a6d73ab5f3983ebeebbac155741ff Mon Sep 17 00:00:00 2001
From: dojyorin <ota_droid@live.jp>
Date: Sun, 21 Jan 2024 03:29:23 +0900
Subject: [PATCH] feat: worker-task

---
 mod.test.ts         |  3 ++-
 mod.ts              |  1 +
 mod.universal.ts    |  3 ++-
 src/worker.ts       | 59 +++++++++++++++++++++++++++++++++++++++++++++
 test/worker.test.ts | 23 ++++++++++++++++++
 5 files changed, 87 insertions(+), 2 deletions(-)
 create mode 100644 src/worker.ts
 create mode 100644 test/worker.test.ts

diff --git a/mod.test.ts b/mod.test.ts
index 44d2d4b..fec756e 100644
--- a/mod.test.ts
+++ b/mod.test.ts
@@ -14,4 +14,5 @@ import "./test/platform.deno.test.ts";
 import "./test/process.deno.test.ts";
 import "./test/stream.test.ts";
 import "./test/text.test.ts";
-import "./test/time.test.ts";
\ No newline at end of file
+import "./test/time.test.ts";
+import "./test/worker.test.ts";
\ No newline at end of file
diff --git a/mod.ts b/mod.ts
index b1fd6ed..81ad9cc 100644
--- a/mod.ts
+++ b/mod.ts
@@ -9,6 +9,7 @@ export * from "./src/minipack.ts";
 export * from "./src/stream.ts";
 export * from "./src/text.ts";
 export * from "./src/time.ts";
+export * from "./src/worker.ts";
 
 export * from "./src/env.deno.ts";
 export * from "./src/json.deno.ts";
diff --git a/mod.universal.ts b/mod.universal.ts
index 51d84c2..5a28eaa 100644
--- a/mod.universal.ts
+++ b/mod.universal.ts
@@ -8,4 +8,5 @@ export * from "./src/import.ts";
 export * from "./src/minipack.ts";
 export * from "./src/stream.ts";
 export * from "./src/text.ts";
-export * from "./src/time.ts";
\ No newline at end of file
+export * from "./src/time.ts";
+export * from "./src/worker.ts";
\ No newline at end of file
diff --git a/src/worker.ts b/src/worker.ts
new file mode 100644
index 0000000..c8025e7
--- /dev/null
+++ b/src/worker.ts
@@ -0,0 +1,59 @@
+/**
+* WIP.
+*/
+export interface WorkerMessage<T>{
+    message: T;
+    transfer?: Transferable[];
+}
+
+/**
+* WIP.
+*/
+export type WorkerTask<T, K> = (message:T) => WorkerMessage<K> | Promise<WorkerMessage<K>>;
+
+/**
+* WIP.
+* @example
+* ```ts
+* const task = createTask(()=>{});
+* ```
+*/
+export function createTask<T, K>(task:WorkerTask<T, K>){
+    const script = task.toString();
+    const regist = /*js*/`
+        globalThis.onmessage = async({data})=>{
+            const {message, transfer} = await(${script})(data);
+            globalThis.postMessage(message, {
+                transfer: transfer
+            });
+        };
+    `;
+    const url = URL.createObjectURL(new Blob([regist]));
+
+    return (message:T, transfer?:Transferable[])=>{
+        return new Promise<K>((res, rej)=>{
+            const worker = new Worker(url, {
+                type: "module"
+            });
+
+            worker.onmessage = ({data})=>{
+                res(data);
+                worker.terminate();
+            };
+
+            worker.onerror = (e)=>{
+                rej(e);
+                worker.terminate();
+            };
+
+            worker.onmessageerror = (e)=>{
+                rej(e);
+                worker.terminate();
+            };
+
+            worker.postMessage(message, {
+                transfer: transfer
+            });
+        });
+    };
+}
\ No newline at end of file
diff --git a/test/worker.test.ts b/test/worker.test.ts
new file mode 100644
index 0000000..178cb72
--- /dev/null
+++ b/test/worker.test.ts
@@ -0,0 +1,23 @@
+import {assertEquals} from "../deps.test.ts";
+import {createTask} from "../src/worker.ts";
+
+const sample1 = new Uint8Array([1, 2, 3, 4]);
+const sample2 = new Uint8Array([1, 4, 6, 8]);
+
+Deno.test({
+    name: "Worker: Create Task.",
+    async fn(){
+        const task = createTask<Uint8Array, Uint8Array>((v)=>{
+            const result = v.map(n => n * 2);
+
+            return {
+                message: result,
+                transfer: [result]
+            };
+        });
+
+        const result = await task(sample1, [sample1]);
+
+        assertEquals(result, sample2);
+    }
+});
\ No newline at end of file