Merge pull request #2020 from hashicorp/01-popover-float-popover-modi…

…fier

`RichTooltip/Popover` component - `hds-anchored-position` modifier [01]

.changeset/metal-zoos-push.md

@@ -0,0 +1,5 @@
+---
+"@hashicorp/design-system-components": minor
+---
+
+Added `hds-anchored-position` modifier (for internal use)

.changeset/soft-lions-warn.md

@@ -0,0 +1,5 @@
+---
+"@hashicorp/design-system-components": minor
+---
+
+Initial commit to open PR (to be removed later)

packages/components/package.json

@@ -37,6 +37,7 @@
     "@ember/string": "^3.1.1",
     "@ember/test-waiters": "^3.1.0",
     "@embroider/addon-shim": "^1.8.7",
+    "@floating-ui/dom": "^1.6.3",
     "@hashicorp/design-system-tokens": "^2.1.0",
     "@hashicorp/ember-flight-icons": "^5.0.1",
     "ember-a11y-refocus": "^3.0.2",
@@ -255,6 +256,7 @@
       "./components/hds/yield/index.js": "./dist/_app_/components/hds/yield/index.js",
       "./helpers/hds-link-to-models.js": "./dist/_app_/helpers/hds-link-to-models.js",
       "./helpers/hds-link-to-query.js": "./dist/_app_/helpers/hds-link-to-query.js",
+      "./modifiers/hds-anchored-position.js": "./dist/_app_/modifiers/hds-anchored-position.js",
       "./modifiers/hds-clipboard.js": "./dist/_app_/modifiers/hds-clipboard.js",
       "./modifiers/hds-tooltip.js": "./dist/_app_/modifiers/hds-tooltip.js"
     }

packages/components/src/modifiers/hds-anchored-position.js

@@ -0,0 +1,228 @@
+import { modifier } from 'ember-modifier';
+import { assert } from '@ember/debug';
+
+import {
+  autoUpdate,
+  computePosition,
+  offset,
+  flip,
+  shift,
+  limitShift,
+  autoPlacement,
+  arrow,
+  // ---
+  // this could be used in the future if we want to give consumers an option to hide the "floating" element when the "anchor" hides from the viewport
+  // see: https://floating-ui.com/docs/hide
+  // hide,
+  // ---
+  // this could be used in the future if we want to give consumers an option to:
+  // - let the "floating" element auto-resize when there is not enough space (usually vertical) in the viewport to contain the entire "floating" element
+  // - let the "floating" element match the width of the "trigger" (it may have min/max width/heigh via CSS too)
+  // see: https://floating-ui.com/docs/size
+  // notice: below you can find a preliminary code implementation that was tested and worked relatively well
+  // size,
+  // ---
+} from '@floating-ui/dom';
+
+export const DEFAULT_PLACEMENT = 'bottom';
+export const PLACEMENTS = [
+  'top',
+  'top-start',
+  'top-end',
+  'right',
+  'right-start',
+  'right-end',
+  'bottom',
+  'bottom-start',
+  'bottom-end',
+  'left',
+  'left-start',
+  'left-end',
+];
+
+// share the same default value of "padding" for `flip/shift/autoPlacement` options
+// this refers to the minimum distance from the boundaries' edges (the viewport)
+// before the floating element changes its position (flips, shifts, or autoplace itself)
+const DEFAULT_EDGE_DISTANCE = 8;
+
+// we use this function to process all the options provided to the modifier in a single place,
+// in relation to the Floating UI APIs, and keep the modifier code more clean/simple
+export const getFloatingUIOptions = (options) => {
+  let {
+    placement = DEFAULT_PLACEMENT,
+    strategy = 'absolute', // we don't need to use `fixed` if we use the Popover API for the "floating" element (it puts the element in the `top-layer`)
+    offsetOptions,
+    flipOptions = { padding: DEFAULT_EDGE_DISTANCE },
+    shiftOptions = { padding: DEFAULT_EDGE_DISTANCE, limiter: limitShift() },
+    autoPlacementOptions = { padding: DEFAULT_EDGE_DISTANCE },
+    middlewareExtra = [],
+    enableCollisionDetection,
+    arrowElement,
+    arrowPadding,
+  } = options;
+
+  // we build dynamically the list of middleware functions to invoke, depending on the options provided
+
+  const middleware = [];
+
+  // https://floating-ui.com/docs/offset
+  middleware.push(offset(offsetOptions));
+
+  // https://floating-ui.com/docs/flip
+  // https://floating-ui.com/docs/shift
+  // https://floating-ui.com/docs/autoPlacement
+  if (
+    enableCollisionDetection === true ||
+    enableCollisionDetection === 'flip'
+  ) {
+    middleware.push(flip(flipOptions));
+  }
+  if (
+    enableCollisionDetection === true ||
+    enableCollisionDetection === 'shift'
+  ) {
+    middleware.push(shift(shiftOptions));
+  }
+  if (enableCollisionDetection === 'auto') {
+    middleware.push(autoPlacement(autoPlacementOptions));
+  }
+
+  // https://floating-ui.com/docs/arrow
+  if (arrowElement) {
+    middleware.push(
+      arrow({
+        element: arrowElement,
+        padding: arrowPadding ?? 0,
+      })
+    );
+  }
+
+  // TODO? commenting this for now, will need to make this conditional to some argument (and understand how this relates to the `@height` argument)
+  // https://floating-ui.com/docs/size#match-reference-width
+  // size({
+  //   apply({ rects, elements }) {
+  //     Object.assign(elements.floating.style, {
+  //       width: `${rects.reference.width}px`,
+  //     });
+  //   },
+  // });
+  // size({
+  //   apply: ({ availableWidth, availableHeight, middlewareData }) => {
+  //     middlewareData.size = { availableWidth, availableHeight };
+  //   },
+  // }),
+
+  middleware.push(...middlewareExtra);
+
+  return {
+    placement,
+    strategy,
+    middleware,
+  };
+};
+
+// Notice: we use a function-based modifier here instead of a class-based one
+// because it's quite simple in its logic, and doesn't require injecting services
+// see: https://github.com/ember-modifier/ember-modifier#function-based-modifiers
+
+export default modifier((element, positional, named = {}) => {
+  // the element that "floats" next to the "anchor" (whose position is calculated in relation to the anchor)
+  // notice: this is the element the Ember modifier is attached to
+  const floatingElement = element;
+
+  // the element that acts as an "anchor" for the "floating" element
+  // it can be a DOM (string) selector or a DOM element
+  // notice: it's expressed as "positional" argument (array of arguments) for the modifier
+  const _anchorTarget = positional[0];
+  const anchorElement =
+    typeof _anchorTarget === 'string'
+      ? document.querySelector(_anchorTarget)
+      : _anchorTarget;
+
+  assert(
+    '`hds-anchored-position` modifier - the provided "anchoring" element is not defined correctly',
+    anchorElement instanceof HTMLElement || anchorElement instanceof SVGElement
+  );
+
+  // the "arrow" element (optional) associated with the "floating" element
+  // it can be a DOM selector (string) or a DOM element
+  // notice: it's declared inside the "named" argument (object) for the modifier
+  // but we need to extract it also here so it can be used to assign inline styles to it
+  let arrowElement;
+  if (named.arrowElement) {
+    assert(
+      '`hds-anchored-position` modifier - the `element` provided for the "arrow" element is not a valid DOM node',
+      named.arrowElement instanceof HTMLElement ||
+        named.arrowElement instanceof SVGElement
+    );
+
+    arrowElement = named.arrowElement;
+  } else if (named.arrowSelector) {
+    assert(
+      '`hds-anchored-position` modifier - the `selector` provided for the "arrow" element must be a string',
+      typeof named.arrowSelector === 'string'
+    );
+
+    arrowElement = document.querySelector(named.arrowSelector);
+
+    assert(
+      '`hds-anchored-position` modifier - the `selector` provided for the "arrow" element is not a valid DOM selector',
+      arrowElement
+    );
+  }
+
+  // the Floating UI "options" to apply to the "floating" element
+  // notice: we spread the `named` argument and override its `arrowElement` value instead of setting it directly because Ember complains that modifier's arguments must be immutable
+  const floatingOptions = getFloatingUIOptions({ ...named, arrowElement });
+
+  const computeFloatingPosition = async () => {
+    // important to know: `computePosition()` is not stateful, it only positions the "floating" element once
+    // see: https://floating-ui.com/docs/computePosition
+    const state = await computePosition(
+      anchorElement,
+      floatingElement,
+      floatingOptions
+    );
+
+    let { x, y, placement, strategy, middlewareData } = state;
+
+    Object.assign(floatingElement.style, {
+      position: strategy,
+      top: `${y}px`,
+      left: `${x}px`,
+      // TODO? commenting this for now, will need to make this conditional to some argument (and understand how this relates to the `@height` argument)
+      // maxHeight: `${middlewareData.size.availableHeight - 10}px`,
+    });
+
+    if (arrowElement && middlewareData.arrow) {
+      // we assign a "data" attribute to the "arrow" element so we can use CSS (in the consuming components) to position/rotate it accordingly and we avoid calculating at runtime values that technically we already know
+      // (similar to what Tippy.js does: https://github.com/atomiks/tippyjs/blob/master/src/scss/svg-arrow.scss)
+      // IMPORTANT: floating-ui assumes the "arrow" container is square!
+      arrowElement.setAttribute('data-hds-anchored-arrow-placement', placement);
+
+      // we set `x` or `y` value (depends on the position of the arrow in relation to the "floating" element placement)
+      // see: https://floating-ui.com/docs/arrow#usage
+      Object.assign(arrowElement.style, {
+        left:
+          middlewareData.arrow.x != null ? `${middlewareData.arrow.x}px` : '',
+        top:
+          middlewareData.arrow.y != null ? `${middlewareData.arrow.y}px` : '',
+      });
+    }
+  };
+
+  // the `autoUpdate` function automatically updates the position of the floating element when necessary.
+  // it should only be called when the floating element is mounted on the DOM or visible on the screen.
+  // it returns a "cleanup" function that should be invoked when the floating element is removed from the DOM or hidden from the screen.
+  // see: https://floating-ui.com/docs/autoUpdate
+  const cleanupFloatingUI = autoUpdate(
+    anchorElement,
+    floatingElement,
+    computeFloatingPosition
+  );
+
+  // this (teardown) function is run when the element is removed from the DOM
+  return () => {
+    cleanupFloatingUI();
+  };
+});