1 files changed, 49 insertions, 0 deletions
diff --git a/packages/astro/src/runtime/server/scripts.ts b/packages/astro/src/runtime/server/scripts.ts
new file mode 100644
index 000000000..ca9cad1fb
--- /dev/null
+++ b/packages/astro/src/runtime/server/scripts.ts
@@ -0,0 +1,49 @@
+import type { SSRResult } from '../../types/public/internal.js';
+import islandScriptDev from './astro-island.prebuilt-dev.js';
+import islandScript from './astro-island.prebuilt.js';
+
+const ISLAND_STYLES = `<style>astro-island,astro-slot,astro-static-slot{display:contents}</style>`;
+
+export function determineIfNeedsHydrationScript(result: SSRResult): boolean {
+	if (result._metadata.hasHydrationScript) {
+		return false;
+	}
+	return (result._metadata.hasHydrationScript = true);
+}
+
+export function determinesIfNeedsDirectiveScript(result: SSRResult, directive: string): boolean {
+	if (result._metadata.hasDirectives.has(directive)) {
+		return false;
+	}
+	result._metadata.hasDirectives.add(directive);
+	return true;
+}
+
+export type PrescriptType = null | 'both' | 'directive';
+
+function getDirectiveScriptText(result: SSRResult, directive: string): string {
+	const clientDirectives = result.clientDirectives;
+	const clientDirective = clientDirectives.get(directive);
+	if (!clientDirective) {
+		throw new Error(`Unknown directive: ${directive}`);
+	}
+	return clientDirective;
+}
+
+export function getPrescripts(result: SSRResult, type: PrescriptType, directive: string): string {
+	// Note that this is a classic script, not a module script.
+	// This is so that it executes immediate, and when the browser encounters
+	// an astro-island element the callbacks will fire immediately, causing the JS
+	// deps to be loaded immediately.
+	switch (type) {
+		case 'both':
+			return `${ISLAND_STYLES}<script>${getDirectiveScriptText(result, directive)};${
+				process.env.NODE_ENV === 'development' ? islandScriptDev : islandScript
+			}</script>`;
+		case 'directive':
+			return `<script>${getDirectiveScriptText(result, directive)}</script>`;
+		case null:
+			break;
+	}
+	return '';
+}