<script lang="ts">
	import type { PageFragment } from '$gql/graphql';
	import { getSelectionContext } from '$lib/selection/Selection.svelte';
	import SelectionOverlay from '$lib/selection/SelectionOverlay.svelte';
	import { src } from '$lib/Utils';

	interface Props {
		page: PageFragment;
		index: number;
		open: (page: number) => void;
		updateCover: (page: number) => void;
	}

	let { page, index, open, updateCover }: Props = $props();

	const selection = getSelectionContext<PageFragment>();

	let span: 'single' | 'double' | 'triple' = $derived.by(() => {
		const aspectRatio = page.image.aspectRatio;

		if (aspectRatio <= 1) {
			return 'single';
		} else if (aspectRatio > 1 && aspectRatio <= 2) {
			return 'double';
		} else {
			return 'triple';
		}
	});

	function press(event: MouseEvent | KeyboardEvent) {
		if (event instanceof KeyboardEvent && event.key !== 'Enter') {
			return;
		}

		if (selection.active) {
			if (event.ctrlKey) {
				open(index);
			} else if (selectable) {
				selection.update(index, event.shiftKey);
			}
		} else if (event.ctrlKey) {
			updateCover(page.id);
		} else {
			open(index);
		}

		event.preventDefault();
	}

	let selectable = $derived(selection.selectable(page));
	let dim = $derived(selection.active && !selectable);
	let selected = $derived(selection.contains(page.id));
</script>

<div
	class:dim
	role="button"
	tabindex="0"
	class="{span} relative overflow-hidden rounded-sm focus-visible:outline-4 focus-visible:outline-blue-600"
	onclick={press}
	onkeydown={press}
>
	<SelectionOverlay position="top" {selected} />
	<img
		class="h-full w-full object-cover object-[center_top] transition-opacity"
		loading="lazy"
		alt=""
		width={page.image.width}
		height={page.image.height}
		src={src(page.image)}
		title={`${page.path} (${page.image.width} x ${page.image.height})`}
	/>
</div>

<style>
	.dim {
		cursor: not-allowed;
	}

	.dim > img {
		opacity: 0.2;
		filter: grayscale(1);
	}

	.double {
		grid-column: span 2;
	}

	.triple {
		grid-column: span 3;
	}
</style>
