add umami analytics loader

src/lib/Umami.svelte

@@ -0,0 +1,78 @@
+<script lang="ts">
+	import { dev } from '$app/environment';
+	import { onMount } from 'svelte';
+	import type { TrackingManager } from './tracking.svelte.ts';
+
+	interface Props {
+		/**
+		 * The URL of the Umami instance. For example: https://umami.example.com.
+		 * Do not include a trailing slash, the script path will be appended
+		 * automatically (default: /script.js).
+		 */
+		umamiURL: string;
+		/** Website ID to associate tracking data as configured in Umami */
+		websiteID: string;
+		/**
+		 * Tracking manager to handle user consent for tracking. If omitted,
+		 * tracking will always be enabled.
+		 */
+		trackingManager?: TrackingManager;
+	}
+
+	let { umamiURL, websiteID, trackingManager }: Props = $props();
+
+	const consentGranted = $derived(trackingManager ? trackingManager.consent === true : true);
+
+	// Development overrides to prevent dirty analytics
+	const devConsoleTag = $derived(`[dev][consent: ${consentGranted ? 'granted' : 'revoked'}]`);
+	const devOverride = {
+		track: (...args: unknown[]): Promise<string> | undefined => {
+			console.log(`${devConsoleTag}: Track called with:`, ...args);
+			return undefined;
+		},
+		identify: (...args: unknown[]): Promise<void> => {
+			console.log(`${devConsoleTag}: Identify called with:`, ...args);
+			return Promise.resolve();
+		}
+	};
+
+	// No-consent quiet override
+	const noConsentOverride = {
+		track: (..._args: unknown[]): Promise<string> | undefined => {
+			return undefined;
+		},
+		identify: (..._args: unknown[]): Promise<void> => {
+			return Promise.resolve();
+		}
+	};
+
+	// If a tracking manager is provided, use it to manage consent state
+	$effect(() => {
+		if (trackingManager) {
+			trackingManager.createService({
+				onConsent: () => {
+					return true;
+				},
+				onRevoke: () => {
+					window.umami = noConsentOverride;
+					return true;
+				}
+			});
+		}
+	});
+
+	if (dev) console.log('[dev]: Umami tracking disabled');
+
+	onMount(() => {
+		if (dev) {
+			// In development mode, override the umami global object
+			window.umami = devOverride;
+		}
+	});
+</script>
+
+<svelte:head>
+	{#if !dev && consentGranted}
+		<script defer src="{umamiURL}/script.js" data-website-id={websiteID}></script>
+	{/if}
+</svelte:head>