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@@ -0,0 +1,38 @@
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+import { tick } from 'svelte';
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+import type { ActionReturn } from 'svelte/action';
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+
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+interface Attributes {
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+ 'on:image-error'?: (e: CustomEvent) => void;
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+ 'on:image-load'?: (e: CustomEvent) => void;
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+}
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+
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+export function imageLoad(img: HTMLImageElement): ActionReturn<void, Attributes> {
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+ const onImageError = () => img.dispatchEvent(new CustomEvent('image-error'));
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+ const onImageLoaded = () => img.dispatchEvent(new CustomEvent('image-load'));
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+
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+ if (img.complete) {
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+ // Browser has fetched the image, naturalHeight is used to check
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+ // if any loading errors have occurred.
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+ const loadingError = img.naturalHeight === 0;
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+
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+ // Report status after a tick, to make sure event listeners are registered.
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+ if (loadingError) {
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+ tick().then(onImageError);
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+ } else {
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+ tick().then(onImageLoaded);
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+ }
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+
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+ return {};
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+ }
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+
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+ // Image has not been loaded yet, report status with event listeners.
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+ img.addEventListener('load', onImageLoaded, { once: true });
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+ img.addEventListener('error', onImageError, { once: true });
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+
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+ return {
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+ destroy() {
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+ img.removeEventListener('load', onImageLoaded);
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+ img.removeEventListener('error', onImageError);
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+ }
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+ };
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+}
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