MOBILE-4632 database: Load styles from site plugins

src/addons/mod/data/components/index/addon-mod-data-index.html

@@ -75,9 +75,7 @@
     </ng-container>
 
     <div class="addon-data-contents addon-data-entries addon-data-entries-{{database.id}}" *ngIf="!isEmpty && database">
-        <core-style [css]="database.csstemplate" prefix="div.addon-data-entries.addon-data-entries-{{database.id}}" />
-
-        <core-compile-html [text]="entriesRendered" [jsData]="jsData" [extraImports]="extraImports" />
+        <core-compile-html [text]="entriesRendered" [jsData]="jsData" [extraImports]="extraImports" [cssCode]="database.csstemplate" />
     </div>
 
 

src/addons/mod/data/pages/edit/edit.html

@@ -21,10 +21,9 @@ <h1>
             [courseId]="database?.course" />
 
         <div class="addon-data-contents addon-data-edit-entry {{cssClass}}" *ngIf="database">
-            <core-style [css]="database.csstemplate" prefix="div.addon-data-edit-entry.{{cssClass}}" />
-
             <form (ngSubmit)="save($event)" [formGroup]="editForm" #editFormEl>
-                <core-compile-html [text]="editFormRender" [jsData]="jsData" [extraImports]="extraImports" />
+                <core-compile-html [text]="editFormRender" [jsData]="jsData" [extraImports]="extraImports"
+                    [cssCode]="database.csstemplate" />
             </form>
         </div>
     </core-loading>

src/addons/mod/data/pages/entry/entry.html

@@ -28,9 +28,8 @@ <h1>
             [courseId]="courseId" />
 
         <div class="addon-data-contents addon-data-entry addon-data-entries-{{database.id}}" *ngIf="database && entry">
-            <core-style [css]="database.csstemplate" prefix="div.addon-data-entry.addon-data-entries-{{database.id}}" />
-
-            <core-compile-html [text]="entryHtml" [jsData]="jsData" [extraImports]="extraImports" (compiling)="setRenderingEntry($event)" />
+            <core-compile-html [text]="entryHtml" [jsData]="jsData" [extraImports]="extraImports" (compiling)="setRenderingEntry($event)"
+                [cssCode]="database.csstemplate" />
         </div>
 
         <core-rating-rate *ngIf="database && entry && ratingInfo && (!database.approval || entry.approved)" [ratingInfo]="ratingInfo"

src/core/components/components.module.ts

@@ -100,6 +100,7 @@ import { CoreSitesListComponent } from './sites-list/sites-list';
         CoreShowPasswordComponent,
         CoreSitePickerComponent,
         CoreSplitViewComponent,
+        // eslint-disable-next-line deprecation/deprecation
         CoreStyleComponent,
         CoreSwipeSlidesComponent,
         CoreTabComponent,
@@ -155,6 +156,7 @@ import { CoreSitesListComponent } from './sites-list/sites-list';
         CoreShowPasswordComponent,
         CoreSitePickerComponent,
         CoreSplitViewComponent,
+        // eslint-disable-next-line deprecation/deprecation
         CoreStyleComponent,
         CoreSwipeSlidesComponent,
         CoreTabComponent,

src/core/components/style/style.ts

@@ -13,6 +13,7 @@
 // limitations under the License.
 
 import { Component, ElementRef, Input, OnChanges } from '@angular/core';
+import { CoreDom } from '@singletons/dom';
 
 /**
  * Component to add a <style> tag.
@@ -23,6 +24,7 @@ import { Component, ElementRef, Input, OnChanges } from '@angular/core';
  * Example:
  *
  * <core-style [css]="'p { color: red; }'" prefix=".custom-rules"></core-style>
+ * @deprecated since 4.5.0. Not needed anymore, core-compile-html accepts now CSS code.
  */
 @Component({
     selector: 'core-style',
@@ -41,37 +43,11 @@ export class CoreStyleComponent implements OnChanges {
     ngOnChanges(): void {
         if (this.element && this.element.nativeElement) {
             const style = document.createElement('style');
-            style.innerHTML = this.prefixCSS(this.css, this.prefix);
+            style.innerHTML = CoreDom.prefixCSS(this.css, this.prefix);
 
             this.element.nativeElement.innerHTML = '';
             this.element.nativeElement.appendChild(style);
         }
     }
 
-    /**
-     * Add a prefix to all rules in a CSS string.
-     *
-     * @param css CSS code to be prefixed.
-     * @param prefix Prefix css selector.
-     * @returns Prefixed CSS.
-     */
-    protected prefixCSS(css: string, prefix: string): string {
-        if (!css) {
-            return '';
-        }
-
-        if (!prefix) {
-            return css;
-        }
-
-        // Remove comments first.
-        let regExp = /\/\*[\s\S]*?\*\/|([^:]|^)\/\/.*$/gm;
-        css = css.replace(regExp, '');
-
-        // Add prefix.
-        regExp = /([^]*?)({[^]*?}|,)/g;
-
-        return css.replace(regExp, prefix + ' $1 $2');
-    }
-
 }

src/core/features/compile/components/compile-html/compile-html.ts

@@ -38,6 +38,8 @@ import { CorePromisedValue } from '@classes/promised-value';
 import { CoreCompile } from '@features/compile/services/compile';
 import { CoreDomUtils } from '@services/utils/dom';
 import { CoreUtils } from '@services/utils/utils';
+import { CoreWS } from '@services/ws';
+import { CoreDom } from '@singletons/dom';
 
 /**
  * This component has a behaviour similar to $compile for AngularJS. Given an HTML code, it will compile it so all its
@@ -64,6 +66,8 @@ export class CoreCompileHtmlComponent implements OnChanges, OnDestroy, DoCheck {
     @Input() text!: string; // The HTML text to display.
     @Input() javascript?: string; // The Javascript to execute in the component.
     @Input() jsData?: Record<string, unknown>; // Data to pass to the fake component.
+    @Input() cssCode?: string; // The styles to apply.
+    @Input() stylesPath?: string; // The styles URL to apply (only if cssCode is not set).
     @Input() extraImports: unknown[] = []; // Extra import modules.
     @Input() extraProviders: Type<unknown>[] = []; // Extra providers.
     @Input() forceCompile = false; // Set it to true to force compile even if the text/javascript hasn't changed.
@@ -101,12 +105,13 @@ export class CoreCompileHtmlComponent implements OnChanges, OnDestroy, DoCheck {
 
         // Check if there's any change in the jsData object.
         const changes = this.differ.diff(this.jsData || {});
-        if (changes) {
-            this.setInputData();
+        if (!changes) {
+            return;
+        }
+        this.setInputData();
 
-            if (this.componentInstance.ngOnChanges) {
-                this.componentInstance.ngOnChanges(CoreDomUtils.createChangesFromKeyValueDiff(changes));
-            }
+        if (this.componentInstance.ngOnChanges) {
+            this.componentInstance.ngOnChanges(CoreDomUtils.createChangesFromKeyValueDiff(changes));
         }
     }
 
@@ -116,7 +121,8 @@ export class CoreCompileHtmlComponent implements OnChanges, OnDestroy, DoCheck {
     async ngOnChanges(changes: Record<string, SimpleChange>): Promise<void> {
         // Only compile if text/javascript has changed or the forceCompile flag has been set to true.
         if (this.text === undefined ||
-            !(changes.text || changes.javascript || (changes.forceCompile && CoreUtils.isTrueOrOne(this.forceCompile)))) {
+            !(changes.text || changes.javascript || changes.cssCode || changes.stylesPath ||
+                (changes.forceCompile && CoreUtils.isTrueOrOne(this.forceCompile)))) {
             return;
         }
 
@@ -132,11 +138,14 @@ export class CoreCompileHtmlComponent implements OnChanges, OnDestroy, DoCheck {
 
             // Create the component.
             if (this.container) {
+                await this.loadCSSCode();
+
                 this.componentRef = await CoreCompile.createAndCompileComponent(
                     this.text,
                     componentClass,
                     this.container,
                     this.extraImports,
+                    this.cssCode,
                 );
 
                 this.element.addEventListener('submit', (event) => {
@@ -163,6 +172,30 @@ export class CoreCompileHtmlComponent implements OnChanges, OnDestroy, DoCheck {
         this.componentRef?.destroy();
     }
 
+    /**
+     * Retrieve the CSS code from the stylesPath if not loaded yet.
+     */
+    protected async loadCSSCode(): Promise<void> {
+        // Do not allow (yet) to load CSS code to a component that doesn't have text.
+        if (!this.text) {
+            this.cssCode = '';
+
+            return;
+        }
+
+        if (this.stylesPath && !this.cssCode) {
+            this.cssCode = await CoreUtils.ignoreErrors(CoreWS.getText(this.stylesPath));
+        }
+
+        // Prepend all CSS rules with :host to avoid conflicts.
+        if (this.cssCode) {
+            if (!this.cssCode.includes(':host')) {
+                this.cssCode =  CoreDom.prefixCSS(this.cssCode, ':host ::ng-deep', ':host');
+            }
+
+        }
+    }
+
     /**
      * Get a class that defines the dynamic component.
      *

src/core/features/compile/services/compile.ts

@@ -175,19 +175,25 @@ export class CoreCompileProvider {
      * @param componentClass The JS class of the component.
      * @param viewContainerRef View container reference to inject the component.
      * @param extraImports Extra imported modules if needed and not imported by this class.
+     * @param styles CSS code to apply to the component.
      * @returns Promise resolved with the component reference.
      */
     async createAndCompileComponent<T = unknown>(
         template: string,
         componentClass: Type<T>,
         viewContainerRef: ViewContainerRef,
         extraImports: any[] = [], // eslint-disable-line @typescript-eslint/no-explicit-any
+        styles?: string,
     ): Promise<ComponentRef<T> | undefined> {
         // Import the Angular compiler to be able to compile components in runtime.
         await import('@angular/compiler');
 
         // Create the component using the template and the class.
-        const component = Component({ template, host: { 'compiled-component-id': String(this.componentId++) } })(componentClass);
+        const component = Component({
+            template,
+            host: { 'compiled-component-id': String(this.componentId++) },
+            styles,
+        })(componentClass);
 
         const lazyImports = await Promise.all(this.LAZY_IMPORTS.map(getModules => getModules()));
         const imports = [

src/core/features/siteplugins/classes/call-ws-directive.ts

@@ -127,7 +127,7 @@ export class CoreSitePluginsCallWSBaseDirective implements OnInit, OnDestroy {
     }
 
     /**
-     * Directive destroyed.
+     * @inheritdoc
      */
     ngOnDestroy(): void {
         this.invalidateObserver?.unsubscribe();

src/core/services/platform.ts

@@ -22,6 +22,8 @@ import { Device, makeSingleton } from '@singletons';
 @Injectable({ providedIn: 'root' })
 export class CorePlatformService extends Platform {
 
+    private static cssNesting?: boolean;
+
     /**
      * Get platform major version number.
      *
@@ -117,6 +119,38 @@ export class CorePlatformService extends Platform {
         return 'WebAssembly' in window;
     }
 
+    /**
+     * Check if the browser supports CSS nesting.
+     *
+     * @returns Whether the browser supports CSS nesting.
+     */
+    supportsCSSNesting(): boolean {
+        if (CorePlatformService.cssNesting !== undefined) {
+            return CorePlatformService.cssNesting;
+        }
+
+        // Add nested CSS to DOM and check if it's supported.
+        const style = document.createElement('style');
+        style.innerHTML = 'div.nested { &.css { color: red; } }';
+        document.head.appendChild(style);
+
+        // Add an element to check if the nested CSS is applied.
+        const div = document.createElement('div');
+        div.className = 'nested css';
+        document.body.appendChild(div);
+
+        const color = window.getComputedStyle(div).color;
+
+        // Check if color is red.
+        CorePlatformService.cssNesting = color === 'rgb(255, 0, 0)';
+
+        // Clean the DOM.
+        document.head.removeChild(style);
+        document.body.removeChild(div);
+
+        return CorePlatformService.cssNesting;
+    }
+
 }
 
 export const CorePlatform = makeSingleton(CorePlatformService);

src/core/singletons/dom.ts

@@ -16,6 +16,7 @@ import { CoreCancellablePromise } from '@classes/cancellable-promise';
 import { CoreDomUtils } from '@services/utils/dom';
 import { CoreUtils } from '@services/utils/utils';
 import { CoreEventObserver } from '@singletons/events';
+import { CorePlatform } from '@services/platform';
 
 /**
  * Singleton with helper functions for dom.
@@ -684,6 +685,44 @@ export class CoreDom {
         return element;
     }
 
+    /**
+     * Prefix CSS rules.
+     *
+     * @param css CSS code.
+     * @param prefix Prefix to add to CSS rules.
+     * @param prefixIfNested Prefix to add to CSS rules if nested. It may happend we need different prefixes.
+     *          Ie: If nested is supported ::ng-deep is not needed.
+     * @returns Prefixed CSS.
+     */
+    static prefixCSS(css: string, prefix: string, prefixIfNested?: string): string {
+        if (!css) {
+            return '';
+        }
+
+        if (!prefix) {
+            return css;
+        }
+
+        // Check if browser supports CSS nesting.
+        const supportsNesting = CorePlatform.supportsCSSNesting();
+        if (supportsNesting) {
+            prefixIfNested = prefixIfNested ?? prefix;
+
+            // Wrap the CSS with the prefix.
+            return `${prefixIfNested} { ${css} }`;
+        }
+
+        // Fallback.
+        // Remove comments first.
+        let regExp = /\/\*[\s\S]*?\*\/|([^:]|^)\/\/.*$/gm;
+        css = css.replace(regExp, '');
+
+        // Add prefix.
+        regExp = /([^]*?)({[^]*?}|,)/g;
+
+        return css.replace(regExp, prefix + ' $1 $2');
+    }
+
 }
 
 /**