Move code to make sure a clean-up happens on each run.

color.js

@@ -0,0 +1,75 @@
+/**
+ * Calculate light or darker color based on the luminance arg.
+ *
+ * @param  {String} hex Color hex string to calculate on.
+ * @param  {Number} lum Luminance.
+ * @return {String}     The new color hex string.
+ */
+export const colorLuminance = (hex, lum) => {
+  // validate hex string
+  hex = String(hex).replace(/[^0-9a-f]/gi, '');
+  if (hex.length < 6) {
+    hex = hex[0] + hex[0] + hex[1] + hex[1] + hex[2] + hex[2];
+  }
+  lum = lum || 0;
+  // convert to decimal and change luminosity
+  let rgb = '#';
+  let c;
+  let i;
+  for (i = 0; i < 3; i++) {
+    c = parseInt(hex.substr(i * 2, 2), 16);
+    c = Math.round(Math.min(Math.max(0, c + (c * lum)), 255)).toString(16);
+    rgb += ('00' + c).substr(c.length);
+  }
+
+  return rgb;
+}
+
+/**
+ * Calculate an appropriate contrast color.
+ *
+ * @param  {String} hex   Hex string of the color we're searching for the right contrast.
+ * @param  {String} dark  Dark color to return. Defaults to #000000.
+ * @param  {String} light Light color to return. Defaults to #ffffff.
+ * @return {String}       Hex color string with the appropriate contrast color.
+ */
+export const contrastTextColor = (hex, dark, light) => {
+  dark = dark || '#000000';
+  light = light || '#ffffff';
+  const result = /^#?([a-f\d]{2})([a-f\d]{2})([a-f\d]{2})$/i.exec(hex);
+  if (!result) {
+    return dark;
+  }
+  const red = parseInt(result[1], 16);
+  const green = parseInt(result[2], 16);
+  const blue = parseInt(result[3], 16);
+  let brightness;
+  brightness = (red * 299) + (green * 587) + (blue * 114);
+  brightness /= 255000;
+  // values range from 0 to 1
+  // anything greater than 0.6 should be bright enough for dark text
+  if (brightness >= 0.6) {
+    return dark;
+  }
+
+  return light;
+}
+
+/**
+ * Convert rgb(r, g, b) to hex.
+ *
+ * @param  {String} rgb   Rgb string to convert.
+ * @return {String}       The hex string.
+ */
+export const rgbToHex = rgb => {
+  const matches = rgb.match(/rgb\(([0-9]+), ([0-9]+), ([0-9]+)\)/);
+  if (matches.length !== 4) {
+    return '';
+  }
+
+  // From https://gist.github.com/lrvick/2080648.
+  const bin = matches[1] << 16 | matches[2] << 8 | matches[3];
+  return (function(h) {
+    return '#' + new Array(7 - h.length).join('0') + h;
+  })(bin.toString(16).toLowerCase());
+}

package.json

@@ -1,6 +1,6 @@
 {
   "name": "@tp/helpers",
-  "version": "2.3.0",
+  "version": "2.7.1",
   "description": "",
   "main": "closest.js",
   "scripts": {

position.js

@@ -21,6 +21,10 @@ export const Position = function(superClass) {
       el.style.position = 'fixed';
       el.style.zIndex = 1001;
 
+      // Reset max-height and overflow in case the element has been positioned before.
+      el.style.maxHeight = '';
+      el.style.overflowY = '';
+
       // Test if the target is in a different stacking context.
       el.style.left = '0px';
       el.style.top = '0px';
@@ -52,6 +56,12 @@ export const Position = function(superClass) {
         }
       }
 
+      // Ensure top never goes below 0
+      if (top < 0) {
+        compTop += Math.abs(top);
+        top = 0;
+      }
+
       if (options.halign === 'left') {
         left = anchorRect.left;
       }
@@ -74,6 +84,13 @@ export const Position = function(superClass) {
         left = 0;
       }
 
+      // Constrain height to viewport - calculate available height from final top position
+      const availableHeight = window.innerHeight - top;
+      if (elRect.height > availableHeight) {
+        el.style.maxHeight = availableHeight + 'px';
+        el.style.overflowY = 'auto';
+      }
+
       el.style.top = (top - fixTop) + 'px';
       el.style.left = (left - fixLeft) + 'px';
 

reach.js

@@ -1,4 +1,6 @@
 export const reach = (path, data) => {
+  if (!data) return;
+
   const parts = path.split('.');
   let part;
   while (part = parts.shift()) {

upload-files.js

@@ -8,7 +8,7 @@ export const upload = function(superClass) {
      * @param {Object} opts Upload options
      * @returns Promise
      */
-    uploadFiles(url, files, data = {}) {
+    uploadFiles(url, files = [], data = {}) {
       return new Promise((resolve, reject) => {
         const request = new XMLHttpRequest();
         const formData = new FormData();

visibility.js

@@ -0,0 +1,52 @@
+/**
+@license
+Copyright (c) 2025 trading_peter
+This program is available under Apache License Version 2.0
+*/
+
+/**
+ * Orchastrates a intersetion observer to execute code if the element becomes visible or hidden/disconnected.
+ */
+export const Visibility = function(superClass) {
+  return class extends superClass {
+
+    constructor() {
+      super();
+      
+      // Create intersection observer
+      this._observer = new IntersectionObserver(entries => {
+        entries.forEach(entry => {
+          if (entry.isIntersecting) {
+            this.visibilityChanged(true);
+          } else {
+            this.visibilityChanged(false);
+          }
+        });
+      });
+    }
+
+    /**
+     * Invoked when the element becomes either visible / connected or hidden / disconnected.
+     * The callback's logic must be able to handle multiple, successive calls with the same state.
+     * @param {boolean} visible
+     */
+    visibilityChanged(visible) {
+      console.warn(this.tagName, 'should override onVisible');
+    }
+
+    connectedCallback() {
+      super.connectedCallback();
+      // Start observing this element
+      this._observer.observe(this);
+    }
+
+    disconnectedCallback() {
+      super.disconnectedCallback();
+      // Clean up
+      this._observer.unobserve(this);
+      this._observer.disconnect();
+
+      this.visibilityChanged(false);
+    }
+  };
+}

wait-for.js

@@ -0,0 +1,28 @@
+/**
+ * Wait for some test to be true, returns a promise that resolves when condition is met.
+ * Useful to wait for element render, for example. Uses requestAnimationFrame.
+ *
+ * @param  {Function} testFn    Test function to call. Should return true to resolve and false to continue testing.
+ * @param  {Number}   maxTries  Maximum number of rounds to test. If exceeded, the promise rejects. Defaults to 5000.
+ * @return {Promise}  Promise that resolves when test passes or rejects when maxTries is reached
+ */
+export const waitFor = (testFn, maxTries = 5000) => {
+  return new Promise((resolve, reject) => {
+    let tries = 0;
+    const boundTestFn = testFn.bind(this);
+
+    function waiter() {
+      if (tries === maxTries) {
+        return reject(new Error('waitFor: maximum tries exceeded'));
+      }
+      if (!boundTestFn()) {
+        window.requestAnimationFrame(waiter);
+        tries++;
+        return;
+      }
+      resolve(true);
+    }
+
+    waiter();
+  });
+}