feat(pie-card): DSW-2426 image opacity when disabled

.changeset/mean-planets-begin.md

@@ -0,0 +1,5 @@
+---
+"@justeattakeaway/pie-card": minor
+---
+
+[Added] Ability to set images to 50% opacity when disabled

apps/pie-storybook/stories/pie-card.stories.ts

@@ -143,3 +143,18 @@ export const Default = createCardStory();
 export const Outline = createCardStory({ variant: 'outline' });
 export const Inverse = createCardStory({ variant: 'inverse' }, { bgColor: 'dark (container-dark)' });
 export const OutlineInverse = createCardStory({ variant: 'outline-inverse' }, { bgColor: 'dark (container-dark)' });
+export const CardWithImage = createCardStory({
+    ...defaultArgs,
+    slot: `<div style="font-size: calc(var(--dt-font-body-l-size) * 1px); font-family: var(--dt-font-interactive-l-family);">
+        <h2 style="margin-top: 0"> Card title </h2>
+        <p> Card content </p>
+        <p style="margin-bottom: 0"> Lorem ipsum dolor sit amet
+        consectetur adipisicing elit.
+        Fugiat dolore dolorem maxime,
+        quod, in minima esse fugit
+        distinctio, officia et soluta
+        dicta consequuntur commodi officiis
+        tempora asperiores aspernatur atque quas.</p>
+        <img src="https://picsum.photos/200/300?image=0" alt="Sample image" />
+    </div>`
+});

packages/components/pie-card/src/index.ts

@@ -1,9 +1,9 @@
 import {
-    html, LitElement, unsafeCSS, nothing, TemplateResult,
+    html, LitElement, unsafeCSS, nothing, TemplateResult, type PropertyValues,
 } from 'lit';
 import { classMap, type ClassInfo } from 'lit/directives/class-map.js';
 import { ifDefined } from 'lit/directives/if-defined.js';
-import { property } from 'lit/decorators.js';
+import { property, queryAssignedElements } from 'lit/decorators.js';
 import { validPropertyValues, defineCustomElement } from '@justeattakeaway/pie-webc-core';
 import styles from './card.scss?inline';
 import {
@@ -53,6 +53,9 @@ export class PieCard extends LitElement implements CardProps {
     @validPropertyValues(componentSelector, paddingValues, undefined)
     public padding?: CardProps['padding'];
 
+    @queryAssignedElements({ flatten: true })
+    private assignedElements?: HTMLElement[];
+
     /**
      * Renders the card as an anchor element.
      *
@@ -117,6 +120,57 @@ export class PieCard extends LitElement implements CardProps {
         return `padding: ${paddingCSS}`;
     }
 
+    /**
+     * Handles the slot change event and applies/removes opacity to images based on the `disabled` state.
+     *
+     * @private
+     */
+    private handleSlotChange () {
+        this.updateImagesOpacity();
+    }
+
+    /**
+     * Updates opacity of all images (slotted and non-slotted) based on the `disabled` property.
+     *
+     * @private
+     */
+    private updateImagesOpacity (): void {
+        if (this.assignedElements) {
+            // Handle images nested inside slotted elements
+            this.assignedElements.forEach((element) => {
+                const images = element.querySelectorAll('img');
+                this.applyOpacityToImages(images);
+            });
+        }
+
+        // Handle directly slotted images
+        const directImages = this.querySelectorAll('img');
+        this.applyOpacityToImages(directImages);
+    }
+
+    /**
+     * Applies or removes opacity from the given images based on the `disabled` property.
+     *
+     * @param images
+     * @private
+     */
+    private applyOpacityToImages (images: NodeListOf<HTMLImageElement>): void {
+        images.forEach((img) => {
+            img.style.opacity = this.disabled ? '0.5' : '';
+        });
+    }
+
+    /**
+     * Observes changes in the `disabled` property and triggers the update of images' opacity.
+     *
+     * @param changedProperties
+     */
+    updated (changedProperties: PropertyValues<this>) : void {
+        if (changedProperties.has('disabled')) {
+            this.updateImagesOpacity(); // Re-apply styles when disabled state changes
+        }
+    }
+
     render () {
         const {
             variant,
@@ -146,7 +200,7 @@ export class PieCard extends LitElement implements CardProps {
                     aria-label=${aria?.label || nothing}
                     aria-disabled=${disabled ? 'true' : 'false'}
                     style=${paddingCSS || ''}>
-                        <slot></slot>
+                        <slot @slotchange=${this.handleSlotChange}></slot>
                     </div>
                 </div>`;
     }

packages/components/pie-card/test/component/pie-card.spec.ts

@@ -304,4 +304,56 @@ test.describe('PieCard - Component tests', () => {
             });
         });
     });
+
+    test.describe('Prop: disabled', () => {
+        test.describe('when an image exists and the prop `disabled` is set to `true`', () => {
+            test('should set the opacity to 50%', async ({ mount, page }) => {
+                // Arrange
+                const slottedImageContent = `<div data-test-id="slot-content">
+                    <img alt="Sample Image" src="data:image/gif;base64,R0lGODlhAQABAIAAAAUEBA==" />
+                </div>`;
+
+                await mount(PieCard, {
+                    props: {
+                        disabled: true,
+                    } as CardProps,
+                    slots: {
+                        default: slottedImageContent,
+                    },
+                });
+
+                // Act
+                const component = page.locator('[data-test-id="slot-content"]');
+                const image = component.locator('img');
+
+                // Assert the image has the correct opacity
+                await expect(image).toHaveCSS('opacity', '0.5');
+            });
+        });
+
+        test.describe('when an image exists and the prop `disabled` is set to `false`', () => {
+            test('should not set the opacity style on the image element', async ({ mount, page }) => {
+                // Arrange
+                const slottedImageContent = `<div data-test-id="slot-content">
+                    <img alt="Sample Image" src="data:image/gif;base64,R0lGODlhAQABAIAAAAUEBA==" />
+                </div>`;
+
+                await mount(PieCard, {
+                    props: {
+                        disabled: false,
+                    } as CardProps,
+                    slots: {
+                        default: slottedImageContent,
+                    },
+                });
+
+                // Act
+                const component = page.locator('[data-test-id="slot-content"]');
+                const image = component.locator('img');
+
+                // Assert the image has the correct opacity
+                await expect(image).not.toHaveCSS('opacity', '0.5');
+            });
+        });
+    });
 });

packages/components/pie-card/test/visual/pie-card.spec.ts

@@ -1,4 +1,4 @@
-import { test } from '@sand4rt/experimental-ct-web';
+import { test, expect } from '@sand4rt/experimental-ct-web';
 import percySnapshot from '@percy/playwright';
 import type {
     PropObject, WebComponentPropValues, WebComponentTestInput,
@@ -95,3 +95,57 @@ test.describe('PieCard - `padding` prop', async () => {
         await percySnapshot(page, `PIE Card - Padding values | batch number: ${index}`, percyWidths);
     }));
 });
+
+test.describe('PieCard - Disabled Prop Visual Tests', () => {
+    const slotContent = `
+        <div style="padding: 16px;">
+            <h2> Card title </h2>
+            <img src="https://picsum.photos/200/300?image=0" alt="Sample image" />
+            <p> Card content </p>
+        </div>`;
+
+    const renderTestPieCard = (disabled: boolean) => `
+        <pie-card ${disabled ? 'disabled' : ''}>
+            ${slotContent}
+        </pie-card>`;
+
+    test('should set image opacity to 50% when disabled is true', async ({ page, mount }) => {
+        const testComponent = renderTestPieCard(true);
+
+        await mount(
+            WebComponentTestWrapper,
+            {
+                slots: {
+                    component: testComponent.trim(),
+                },
+            },
+        );
+
+        const image = page.locator('img');
+        const opacity = await image.evaluate((img) => getComputedStyle(img).opacity);
+
+        expect(opacity).toBe('0.5');
+
+        await percySnapshot(page, 'PIE Card - Disabled State & image set to opacity of 50%');
+    });
+
+    test('should not set image opacity style when disabled is false', async ({ page, mount }) => {
+        const testComponent = renderTestPieCard(false);
+
+        await mount(
+            WebComponentTestWrapper,
+            {
+                slots: {
+                    component: testComponent.trim(),
+                },
+            },
+        );
+
+        const image = page.locator('img');
+        const opacity = await image.evaluate((img) => getComputedStyle(img).opacity);
+
+        expect(opacity).not.toBe('0.5');
+
+        await percySnapshot(page, 'PIE Card - Enabled State & image opacity not set');
+    });
+});