Emdash source with visual editor image upload fix

Fixes:
1. media.ts: wrap placeholder generation in try-catch
2. toolbar.ts: check r.ok, display error message in popover

packages/core/tests/unit/preview/urls.test.ts

@@ -0,0 +1,161 @@
+import { describe, it, expect } from "vitest";
+
+import { getPreviewUrl, buildPreviewUrl } from "../../../src/preview/urls.js";
+
+// Regex patterns for URL validation
+const RELATIVE_PREVIEW_URL_REGEX = /^\/posts\/hello-world\?_preview=/;
+const ABSOLUTE_PREVIEW_URL_REGEX = /^https:\/\/example\.com\/posts\/hello-world\?_preview=/;
+const BLOG_PREVIEW_URL_REGEX = /^\/blog\/hello-world\?_preview=/;
+const CONTENT_PREVIEW_URL_REGEX = /^\/content\/posts\/view\/hello-world\?_preview=/;
+const BASE64URL_INVALID_CHARS_REGEX = /[+/=]/;
+
+describe("preview URLs", () => {
+	const testSecret = "test-secret-key-for-preview-tokens";
+
+	describe("getPreviewUrl", () => {
+		it("generates relative URL by default", async () => {
+			const url = await getPreviewUrl({
+				collection: "posts",
+				id: "hello-world",
+				secret: testSecret,
+			});
+
+			// Should start with path
+			expect(url).toMatch(RELATIVE_PREVIEW_URL_REGEX);
+
+			// Should have a token
+			const urlObj = new URL(url, "http://example.com");
+			const token = urlObj.searchParams.get("_preview");
+			expect(token).toBeTruthy();
+			expect(token!.split(".").length).toBe(2);
+		});
+
+		it("generates absolute URL with baseUrl", async () => {
+			const url = await getPreviewUrl({
+				collection: "posts",
+				id: "hello-world",
+				secret: testSecret,
+				baseUrl: "https://example.com",
+			});
+
+			expect(url).toMatch(ABSOLUTE_PREVIEW_URL_REGEX);
+		});
+
+		it("respects custom path pattern", async () => {
+			const url = await getPreviewUrl({
+				collection: "posts",
+				id: "hello-world",
+				secret: testSecret,
+				pathPattern: "/blog/{id}",
+			});
+
+			expect(url).toMatch(BLOG_PREVIEW_URL_REGEX);
+		});
+
+		it("supports complex path patterns", async () => {
+			const url = await getPreviewUrl({
+				collection: "posts",
+				id: "hello-world",
+				secret: testSecret,
+				pathPattern: "/content/{collection}/view/{id}",
+			});
+
+			expect(url).toMatch(CONTENT_PREVIEW_URL_REGEX);
+		});
+
+		it("generates URL-safe tokens", async () => {
+			const url = await getPreviewUrl({
+				collection: "posts",
+				id: "test-id",
+				secret: testSecret,
+			});
+
+			// Token should not contain URL-unsafe characters
+			const urlObj = new URL(url, "http://example.com");
+			const token = urlObj.searchParams.get("_preview");
+			expect(token).not.toMatch(BASE64URL_INVALID_CHARS_REGEX);
+		});
+
+		it("substitutes {locale} placeholder", async () => {
+			const url = await getPreviewUrl({
+				collection: "posts",
+				id: "hello-world",
+				secret: testSecret,
+				pathPattern: "/{locale}/{id}",
+				locale: "pt-br",
+			});
+
+			expect(url).toMatch(/^\/pt-br\/hello-world\?_preview=/);
+		});
+
+		it("collapses empty {locale} segment", async () => {
+			const url = await getPreviewUrl({
+				collection: "posts",
+				id: "hello-world",
+				secret: testSecret,
+				pathPattern: "/{locale}/{id}",
+				locale: "",
+			});
+
+			// Empty locale should not leave a leading double slash.
+			expect(url).toMatch(/^\/hello-world\?_preview=/);
+		});
+
+		it("respects expiresIn option", async () => {
+			const shortUrl = await getPreviewUrl({
+				collection: "posts",
+				id: "test",
+				secret: testSecret,
+				expiresIn: "30m",
+			});
+
+			const longUrl = await getPreviewUrl({
+				collection: "posts",
+				id: "test",
+				secret: testSecret,
+				expiresIn: "7d",
+			});
+
+			// Both should be valid but different tokens
+			expect(shortUrl).not.toBe(longUrl);
+		});
+	});
+
+	describe("buildPreviewUrl", () => {
+		it("builds URL from existing token", () => {
+			const token = "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.test-signature";
+
+			const url = buildPreviewUrl({
+				path: "/posts/hello-world",
+				token,
+			});
+
+			expect(url).toBe(`/posts/hello-world?_preview=${token}`);
+		});
+
+		it("builds absolute URL with baseUrl", () => {
+			const token = "test-token";
+
+			const url = buildPreviewUrl({
+				path: "/posts/hello-world",
+				token,
+				baseUrl: "https://example.com",
+			});
+
+			expect(url).toBe(`https://example.com/posts/hello-world?_preview=${token}`);
+		});
+
+		it("preserves existing query params in path", () => {
+			const token = "test-token";
+
+			// Note: buildPreviewUrl doesn't preserve existing params, it starts fresh
+			// This is intentional - the path should be clean
+			const url = buildPreviewUrl({
+				path: "/posts/hello-world",
+				token,
+			});
+
+			expect(url).toContain("_preview=test-token");
+		});
+	});
+});