import { PerformanceItem } from "./PerformanceItem.js";
/**
 * TODO: This stores into memory. May cause memory leaks in the long run if not cleaned up!
 */
let timer: { [uniqueId: string]: number } = {};

/**
Function that lets you measure performance inside any function with ease.

Usage:

Firstly, make a performance array, and a unique execution id, and start the measurement, like so:

```ts
import { generateUniqueId, getNewPerformance, PerformanceItem, cleanupTimer } from "from-anywhere/node";

// at the start of your function

const executionId = generateUniqueId();
const performance: (PerformanceItem | undefined)[] = [];
getNewPerformance("start", executionId, true)
```


After that, push a new performance item at every step you want to measure. Provide your label describing what happened before this (the step you are measuring).


```ts
performance.push(getNewPerformance("your label", executionId));
```

At the end of your function, you can view your performance array by printing it on the console (or store it somewhere if you like)

Don't forget to run `cleanupTimer`, or you'll run into memory leaks!

```ts
cleanupTimer(executionId);
```

 */
export const getNewPerformance = (
  label: string,
  uniqueId: string,
  isNew?: boolean,
): PerformanceItem | undefined => {
  const timePrevious = timer[uniqueId];
  const timeNow = Date.now();
  timer[uniqueId] = timeNow;

  if (isNew) return;

  const durationMs = timeNow - timePrevious;

  return { label, durationMs };
};

/**
 * Ensure you run this after finishing the measurement, or you'll run into memory leaks!
 */
export const cleanupTimer = (uniqueId: string) => {
  delete timer[uniqueId];
};