feat(downstate): docs + implementation for example components (#2520)

* feat(downstate): docs + implementation for example components

* docs: update mdx

* docs: reorg, stories live within foundations

* docs: decorator for down state dimension tokens

* docs: fix mdx hierarchy console error

* fix: small iconOnly button gets min perspective

* docs: use markdown, update language

* fix: disabled, readonly checkbox doesnt have down state

* chore(button,checkbox): update package versions

.storybook/decorators/index.js

@@ -2,6 +2,7 @@ import { makeDecorator, useEffect } from "@storybook/preview-api";
 import { html } from "lit";
 
 export { withContextWrapper } from "./contextsWrapper.js";
+export { withDownStateDimensionCapture } from "./withDownStateDimensionCapture.js";
 export { withTestingPreviewWrapper } from "./withTestingPreviewWrapper.js";
 
 /**

.storybook/decorators/withDownStateDimensionCapture.js

@@ -0,0 +1,19 @@
+export const withDownStateDimensionCapture = (selector) => (Story, context) => {
+  const captureDownStateDimensions = () => {
+    const components = document.querySelectorAll(selector);
+    components.forEach((component) => {
+      const { width, height } = component.getBoundingClientRect();
+      component.style.setProperty('--spectrum-downstate-width', `${width}px`);
+      component.style.setProperty('--spectrum-downstate-height', `${height}px`);
+    });
+  };
+
+  document.addEventListener("DOMContentLoaded", () => {
+    // Wait to make sure the story is fully rendered (otherwise width/height can be wrong)
+    setTimeout(() => {
+        captureDownStateDimensions();
+    }, 100);
+  });
+
+  return Story(context);
+};

.storybook/foundations/down-state/button-down-state.stories.js

@@ -0,0 +1,32 @@
+import { Template } from "../../../components/button/stories/template";
+
+export default {
+	title: "Foundations/Down state",
+	description:
+		"Buttons allow users to perform an action or to navigate to another page. They have multiple styles for various needs, and are ideal for calling attention to where a user needs to do something in order to move forward in a flow.",
+	component: "Button",
+	args: {
+		rootClass: "spectrum-Button",
+	},
+	parameters: {
+		actions: {
+			handles: ['click .spectrum-Button'],
+		},
+		status: {
+			type: process.env.MIGRATED_PACKAGES.includes("button")
+				? "migrated"
+				: undefined,
+		},
+	},
+	tags: ['foundation'],
+};
+
+export const ButtonDownState = Template.bind({});
+ButtonDownState.args = {
+	label: "Edit",
+	variant: "accent",
+	customStyles: {
+		"--spectrum-downstate-width": "72px",
+		"--spectrum-downstate-height": "32px"
+	}
+};

.storybook/foundations/down-state/checkbox-down-state.stories.js

@@ -0,0 +1,27 @@
+import { Template } from "../../../components/checkbox/stories/template";
+
+export default {
+	title: "Foundations/Down state",
+	description:
+		"Checkboxes allow users to select multiple items from a list of individual items, or mark one individual item as selected.",
+	component: "Checkbox",
+	args: {
+		rootClass: "spectrum-Checkbox",
+	},
+	parameters: {
+		actions: {
+			handles: ['click input[type="checkbox"]'],
+		},
+		status: {
+			type: process.env.MIGRATED_PACKAGES.includes("checkbox")
+				? "migrated"
+				: undefined,
+		},
+	},
+	tags: ['foundation'],
+};
+
+export const CheckboxDownState = Template.bind({});
+CheckboxDownState.args = {
+	label: "Checkbox",
+};

.storybook/foundations/down-state/down-state.mdx

@@ -0,0 +1,44 @@
+import { Meta, Story } from '@storybook/blocks';
+import * as Checkbox from './checkbox-down-state.stories.js';
+import * as Button from './button-down-state.stories.js';
+
+<Meta title="Foundations/Down state" />
+
+# Down state
+
+Down state is a Spectrum 2 feature that creates the illusion of components being pressed-in when active. This functionality is already included in Spectrum 2 components that require down state in this project. It is implemented with a CSS transform. The implementation depends on the size of the interactable element, as shown in the examples below.
+
+## Examples
+
+### Minimum perspective
+
+For elements that have a width of 24px or less, the minimum perspective token is used to apply the down state. One example of a component that uses this token is the checkbox:
+
+<Story of={Checkbox.CheckboxDownState} />
+
+In this case, we use the minimum perspective token:
+
+```
+transform:
+  perspective(var(--spectrum-component-size-minimum-perspective-down))
+  translateZ(var(--spectrum-component-size-difference-down));
+```
+
+### Calculated perspective
+
+For elements that have a width of greater than 24px, we need to use the component's width and height to apply the down state. One example of a component that uses this logic is the button:
+
+<Story of={Button.ButtonDownState} />
+
+In this case, we use a max formula to calculate the perspective based on component width and height (this helps us account for components that may be very wide):
+
+```
+transform:
+  perspective(max(
+    var(--spectrum-downstate-height),
+    var(--spectrum-downstate-width) * var(--spectrum-component-size-width-ratio-down)
+  ))
+  translateZ(var(--spectrum-component-size-difference-down));
+```
+
+*Note that in this case, users are required to develop an implementation to determine the width and height of the component. Assign these values to the `--spectrum-downstate-width` and `--spectrum-downstate-height` custom properties in a `style` attribute on the HTML element to expose them for use in the CSS.*

.storybook/main.js

@@ -12,6 +12,8 @@ module.exports = {
 	stories: [
 		"../components/*/stories/*.stories.js",
 		"./guides/*.mdx",
+		"./foundations/*/*.mdx",
+		"./foundations/*/*.stories.js",
 		"./deprecated/*/*.stories.js",
 	],
 	rootDir: "../",

.storybook/manager.js

@@ -50,7 +50,7 @@ addons.setConfig({
 	sidebar: {
 		showRoots: false,
 		filters: {
-			patterns: (item) => !item.id.includes('forced-colors'),
+			patterns: (item) => !(item.id.includes('forced-colors') || item.tags.includes('foundation')),
 		}
 	},
 });

.storybook/preview.js

@@ -3,11 +3,11 @@ import DocumentationTemplate from './DocumentationTemplate.mdx';
 
 import { withActions } from "@storybook/addon-actions/decorator";
 import {
-	withContextWrapper,
-	withLanguageWrapper,
-	withReducedMotionWrapper,
-	withTestingPreviewWrapper,
-	withTextDirectionWrapper,
+  withContextWrapper,
+  withLanguageWrapper,
+  withReducedMotionWrapper,
+  withTestingPreviewWrapper,
+  withTextDirectionWrapper,
 } from "./decorators/index.js";
 
 // https://github.com/storybookjs/storybook-addon-console
@@ -191,7 +191,7 @@ export const parameters = {
 	options: {
 		storySort: {
 			method: "alphabetical",
-			order: ['Guides', ['Contributing', '*', 'Adobe Code of Conduct', 'Changelog'], 'Components', ['Docs', 'Default', '*'], '*'],
+			order: ['Guides', ['Contributing', '*', 'Adobe Code of Conduct', 'Changelog'], 'Foundations', 'Components', ['Docs', 'Default', '*'], '*'],
 			includeNames: true,
 		},
 	},

components/button/index.css

@@ -26,7 +26,12 @@ governing permissions and limitations under the License.
   --spectrum-button-focus-indicator-color: var(--spectrum-focus-indicator-color);
   --spectrum-button-intended-icon-size: var(--spectrum-workflow-icon-size-50);
 
+<<<<<<< HEAD
   --mod-progress-circle-position: absolute;
+=======
+  /* stylelint-disable-next-line spectrum-tools/no-unknown-custom-properties */
+  --spectrum-downstate-perspective: max(var(--spectrum-downstate-height), var(--spectrum-downstate-width) * var(--spectrum-component-size-width-ratio-down));
+>>>>>>> 5a532e656 (feat(downstate): docs + implementation for example components (#2520))
 }
 
 .spectrum-Button--sizeS {
@@ -45,6 +50,10 @@ governing permissions and limitations under the License.
   --spectrum-button-bottom-to-text: var(--spectrum-button-bottom-to-text-small);
   --spectrum-button-top-to-icon: var(--spectrum-component-top-to-workflow-icon-75);
   --spectrum-button-intended-icon-size: var(--spectrum-workflow-icon-size-75);
+
+  &.spectrum-Button--iconOnly {
+    --spectrum-downstate-perspective: var(--spectrum-component-size-minimum-perspective-down);
+  }
 }
 
 .spectrum-Button--sizeM {
@@ -131,6 +140,10 @@ governing permissions and limitations under the License.
     box-shadow: none;
   }
 
+  &:active {
+    transform: perspective(var(--spectrum-downstate-perspective)) translateZ(var(--spectrum-component-size-difference-down));
+  }
+
   .spectrum-Icon {
     /* Any block-size difference between the intended workflow icon size and actual icon used.
        Helps support any existing use of smaller UI icons instead of intended Workflow icons. */

components/button/package.json

@@ -1,6 +1,6 @@
 {
 	"name": "@spectrum-css/button",
-	"version": "13.0.0",
+	"version": "14.0.0-next.2",
 	"description": "The Spectrum CSS button component",
 	"license": "Apache-2.0",
 	"author": "Adobe",

components/button/stories/button.stories.js

@@ -1,5 +1,7 @@
 import { html } from "lit";
 import { styleMap } from "lit/directives/style-map.js";
+import { when } from "lit/directives/when.js";
+import { withDownStateDimensionCapture } from "../../../.storybook/decorators";
 
 import { default as IconStories } from "@spectrum-css/icon/stories/icon.stories.js";
 import { Template as Typography } from "@spectrum-css/typography/stories/template.js";
@@ -12,6 +14,7 @@ import { Template } from "./template";
 export default {
 	title: "Components/Button",
 	component: "Button",
+	decorators: [withDownStateDimensionCapture('.spectrum-Button:not(:disabled)')],
 	argTypes: {
 		size: {
 			name: "Size",

components/checkbox/index.css

@@ -152,6 +152,12 @@ governing permissions and limitations under the License.
     }
   }
 
+  &:not(.is-readOnly):active {
+    .spectrum-Checkbox-input:not(:disabled) + .spectrum-Checkbox-box {
+      transform: perspective(var(--spectrum-component-size-minimum-perspective-down)) translateZ(var(--spectrum-component-size-difference-down));
+    }
+  }
+
   /* Selected Invalid */
   &.is-invalid {
     .spectrum-Checkbox-input:checked + .spectrum-Checkbox-box,