From 19dff46c9b33b680c073003387cde3d812a9b77f Mon Sep 17 00:00:00 2001
From: Geoffrey Hendrey <geoff.hendrey@gmail.com>
Date: Wed, 30 Oct 2024 19:33:10 -0700
Subject: [PATCH] wip

---
 src/test/TemplateProcessor.test.js | 60 +++++++++++++++++++++++++++++-
 src/utils/GeneratorManager.ts      | 34 +++++++++++------
 2 files changed, 81 insertions(+), 13 deletions(-)

diff --git a/src/test/TemplateProcessor.test.js b/src/test/TemplateProcessor.test.js
index ad83e777..942e1519 100644
--- a/src/test/TemplateProcessor.test.js
+++ b/src/test/TemplateProcessor.test.js
@@ -3110,14 +3110,14 @@ test("test close", async () => {
     }
 });
 
-test("test generate", async () => {
+test("test generate array", async () => {
     const o = {
         "delayMs": 10,
         "a":"${[1..10]~>$generate(delayMs)}",
         "b": "${a}"
     };
 
-    const callCount = 10;
+    const callCount = 0;
     let resolvePromise;
     const allCallsMade = new Promise((resolve) => {
         resolvePromise = resolve;
@@ -3141,6 +3141,62 @@ test("test generate", async () => {
     }
 });
 
+test("test generate single item", async () => {
+    const o = {
+        "a":"${$generate(10)}",
+        "b": "${a}"
+    };
+
+    const callCount = 0;
+    let resolvePromise;
+    const allCallsMade = new Promise((resolve) => {
+        resolvePromise = resolve;
+    });
+
+    const changeHandler = jest.fn((data, ptr) => {
+        expect(ptr).toBe("/b"); // Ensure correct pointer
+        resolvePromise(); // Resolve the promise when callCount is reached
+    });
+    const tp = new TemplateProcessor(o);
+    tp.setDataChangeCallback('/b', changeHandler);
+    try {
+        await tp.initialize();
+        await allCallsMade;
+        expect(changeHandler).toHaveBeenCalledTimes(1);
+        expect(tp.output.b).toBe(10);
+    } finally {
+        await tp.close();
+    }
+});
+
+test("test generate function result", async () => {
+    const o = {
+        "a":"${$generate(function(){10})}",
+        "b": "${a}"
+    };
+    
+    let resolvePromise;
+    const allCallsMade = new Promise((resolve) => {
+        resolvePromise = resolve;
+    });
+
+    const changeHandler = jest.fn((data, ptr) => {
+        expect(ptr).toBe("/b"); // Ensure correct pointer
+        resolvePromise(); // Resolve the promise when callCount is reached
+    });
+
+    const tp = new TemplateProcessor(o);
+    tp.setDataChangeCallback('/b', changeHandler);
+    try {
+        await tp.initialize();
+        await allCallsMade;
+        expect(changeHandler).toHaveBeenCalledTimes(1);
+        expect(tp.output.b).toBe(10);
+    } finally {
+        await tp.close();
+    }
+});
+
 
 test("test lifecycle manager", async () => {
     const o = {
diff --git a/src/utils/GeneratorManager.ts b/src/utils/GeneratorManager.ts
index 586726e8..181e40a5 100644
--- a/src/utils/GeneratorManager.ts
+++ b/src/utils/GeneratorManager.ts
@@ -9,28 +9,40 @@ export class GeneratorManager{
     }
 
     /**
-     * Generates an asynchronous generator that yields items from the provided array,
+     * Generates an asynchronous generator that yields items from the provided generateMe,
      * separated by the specified timeout, and automatically registers the generator.
      *
-     * @param array The array of items to yield.
+     * @param generateMe The item or array of items to yield. If generate me is a function, the function is called to
+     * get a result, and recursively passed to generate()
      * @param timeout The delay in milliseconds between yields. Defaults to 0.
      * @returns The registered asynchronous generator.
      */
-    public generate = (array: any[], timeout: number = 0): AsyncGenerator<any, void, unknown> => {
+    public generate = (generateMe: any[]|any| (() => any), timeout: number = 0): AsyncGenerator<any, void, unknown> => {
         if (this.templateProcessor.isClosed) {
             throw new Error("generate() cannot be called on a closed TemplateProcessor");
         }
         const timerManager = this.templateProcessor.timerManager;
-
-        const generator = async function* () {
-            for (let i = 0; i < array.length; i++) {
-                yield array[i];
-                if (timeout > 0 && i < array.length - 1) {
-                    await new Promise<void>((resolve) => timerManager.setTimeout(resolve, timeout));
+        //yield array items separated by timeout
+        if(Array.isArray(generateMe)) {
+            return async function* () {
+                for (let i = 0; i < generateMe.length; i++) {
+                    yield generateMe[i];
+                    if (timeout > 0 && i < generateMe.length - 1) {
+                        await new Promise<void>((resolve) => timerManager.setTimeout(resolve, timeout));
+                    }
                 }
-            }
+            }();
+        }
+        //call function and return result
+        if(typeof generateMe === 'function'){
+            return async function*(){
+                yield (generateMe as ()=>any)();
+            }();
+        }
+        //yield individual item
+        return async function*(){
+            yield generateMe;
         }();
-        return generator;
     };