(function () {
	'use strict';

	var remoteBase = 'https://cdn.jsdelivr.net/npm/photoswipe@5.4.4/dist/';
	var config = window.kalmInnPhotoSwipe || {};
	var galleries = Array.prototype.slice.call(document.querySelectorAll('[data-kalm-gallery]'));

	config.cssUrl = config.cssUrl || remoteBase + 'photoswipe.css';
	config.lightboxUrl = config.lightboxUrl || remoteBase + 'photoswipe-lightbox.esm.js';
	config.coreUrl = config.coreUrl || remoteBase + 'photoswipe.esm.js';
	config.fallbackCssUrl = config.fallbackCssUrl || remoteBase + 'photoswipe.css';
	config.fallbackLightboxUrl = config.fallbackLightboxUrl || remoteBase + 'photoswipe-lightbox.esm.js';
	config.fallbackCoreUrl = config.fallbackCoreUrl || remoteBase + 'photoswipe.esm.js';

	if (!galleries.length) {
		return;
	}

	function normalizeUrl(url) {
		try {
			return new URL(url, document.baseURI).href;
		} catch (error) {
			return '';
		}
	}

	function assetHasMime(url, expectedPattern) {
		if (!url || typeof window.fetch !== 'function') {
			return Promise.resolve(false);
		}

		return window.fetch(url, {
			method: 'HEAD',
			credentials: 'same-origin'
		}).then(function (response) {
			var contentType = response.headers.get('content-type') || '';
			return response.ok && expectedPattern.test(contentType);
		}).catch(function () {
			return false;
		});
	}

	function photoSwipeStylesAreReady() {
		var probe;
		var ready;

		if (!document.body) {
			return false;
		}

		probe = document.createElement('div');
		probe.className = 'pswp';
		probe.hidden = true;
		document.body.appendChild(probe);
		ready = window.getComputedStyle(probe).position === 'fixed';
		probe.remove();

		return ready;
	}

	function loadStylesheet(url) {
		var normalizedUrl = normalizeUrl(url);

		if (!normalizedUrl) {
			return Promise.reject(new Error('Invalid PhotoSwipe stylesheet URL.'));
		}

		return new Promise(function (resolve, reject) {
			var links = Array.prototype.slice.call(document.querySelectorAll('link[rel="stylesheet"]'));
			var link = links.find(function (candidate) {
				return normalizeUrl(candidate.href) === normalizedUrl;
			});
			var elapsed = 0;
			var interval;
			var timeout = 3000;

			function cleanup() {
				window.clearInterval(interval);
				link.removeEventListener('error', onError);
			}

			function onError() {
				cleanup();
				reject(new Error('PhotoSwipe stylesheet could not be loaded.'));
			}

			if (!link) {
				link = document.createElement('link');
				link.rel = 'stylesheet';
				link.href = normalizedUrl;
				link.setAttribute('data-kalm-photoswipe-style', 'true');
				document.head.appendChild(link);
			}

			link.addEventListener('error', onError, { once: true });

			interval = window.setInterval(function () {
				elapsed += 50;

				if (photoSwipeStylesAreReady()) {
					cleanup();
					resolve();
				} else if (elapsed >= timeout) {
					cleanup();
					reject(new Error('PhotoSwipe stylesheet did not become active.'));
				}
			}, 50);
		});
	}

	function ensureStyles() {
		var primaryUrl = normalizeUrl(config.cssUrl);
		var fallbackUrl = normalizeUrl(config.fallbackCssUrl);

		if (photoSwipeStylesAreReady()) {
			return Promise.resolve();
		}

		function usePrimaryStyles() {
			if (!config.usesLocalModules) {
				return loadStylesheet(primaryUrl);
			}

			return assetHasMime(primaryUrl, /^text\/css(?:;|$)/i).then(function (validMime) {
				if (!validMime) {
					throw new Error('Local PhotoSwipe CSS has an invalid MIME type.');
				}

				return loadStylesheet(primaryUrl);
			});
		}

		return usePrimaryStyles().catch(function (error) {
			if (!fallbackUrl || fallbackUrl === primaryUrl) {
				throw error;
			}

			return loadStylesheet(fallbackUrl);
		});
	}

	function importModules(lightboxUrl, coreUrl) {
		return Promise.all([
			import(lightboxUrl),
			import(coreUrl)
		]);
	}

	function loadModules() {
		var primaryLightbox = normalizeUrl(config.lightboxUrl);
		var primaryCore = normalizeUrl(config.coreUrl);
		var fallbackLightbox = normalizeUrl(config.fallbackLightboxUrl);
		var fallbackCore = normalizeUrl(config.fallbackCoreUrl);

		function usePrimaryModules() {
			if (!config.usesLocalModules) {
				return importModules(primaryLightbox, primaryCore);
			}

			return Promise.all([
				assetHasMime(primaryLightbox, /(?:java|ecma)script/i),
				assetHasMime(primaryCore, /(?:java|ecma)script/i)
			]).then(function (validMime) {
				if (!validMime[0] || !validMime[1]) {
					throw new Error('Local PhotoSwipe modules have an invalid MIME type.');
				}

				return importModules(primaryLightbox, primaryCore);
			});
		}

		return usePrimaryModules().catch(function (error) {
			if (
				!fallbackLightbox ||
				!fallbackCore ||
				(fallbackLightbox === primaryLightbox && fallbackCore === primaryCore)
			) {
				throw error;
			}

			return importModules(fallbackLightbox, fallbackCore);
		});
	}

	function enableHoverEffect(gallery) {
		gallery.querySelectorAll('.kalm-gallery__item').forEach(function (item) {
			if (item.dataset.kalmGalleryHoverReady) {
				return;
			}

			item.dataset.kalmGalleryHoverReady = 'true';
			item.addEventListener('mousemove', function (event) {
				var rect = item.getBoundingClientRect();
				var x = ((event.clientX - rect.left) / rect.width - 0.5) * -10;
				var y = ((event.clientY - rect.top) / rect.height - 0.5) * -10;

				item.style.setProperty('--kalm-gallery-hover-x', x + 'px');
				item.style.setProperty('--kalm-gallery-hover-y', y + 'px');
			});

			item.addEventListener('mouseleave', function () {
				item.style.removeProperty('--kalm-gallery-hover-x');
				item.style.removeProperty('--kalm-gallery-hover-y');
			});
		});
	}

	galleries.forEach(enableHoverEffect);

	Promise.all([ensureStyles(), loadModules()]).then(function (assets) {
		var modules = assets[1];
		var PhotoSwipeLightbox = modules[0] && modules[0].default;
		var PhotoSwipe = modules[1] && modules[1].default;

		if (typeof PhotoSwipeLightbox !== 'function' || typeof PhotoSwipe !== 'function') {
			throw new Error('PhotoSwipe modules do not expose the expected constructors.');
		}

		window.kalmInnPhotoSwipeInstances = window.kalmInnPhotoSwipeInstances || [];

		galleries.forEach(function (gallery) {
			var items = gallery.querySelectorAll('.kalm-gallery__item[href][data-pswp-width][data-pswp-height]');
			var lightbox;

			if (!items.length || gallery.dataset.kalmPhotoSwipeReady) {
				return;
			}

			lightbox = new PhotoSwipeLightbox({
				gallery: gallery,
				children: '.kalm-gallery__item[href][data-pswp-width][data-pswp-height]',
				pswpModule: PhotoSwipe,
				appendToEl: document.body,
				mainClass: 'kalm-photoswipe'
			});

			lightbox.init();
			gallery.dataset.kalmPhotoSwipeReady = 'true';
			window.kalmInnPhotoSwipeInstances.push(lightbox);
		});
	}).catch(function (error) {
		if (window.console && typeof window.console.warn === 'function') {
			window.console.warn('[Kalm Inn] PhotoSwipe non disponibile; i link alle immagini restano attivi.', error);
		}
	});
}());