Move helper to new file and minor refactor

extensions/ql-vscode/src/common/github-url-identifier-helper.ts

@@ -0,0 +1,71 @@
+import { OWNER_REGEX, REPO_REGEX } from "../pure/helpers-pure";
+
+/**
+ * Checks if a string is a valid GitHub NWO.
+ * @param identifier The GitHub NWO
+ * @returns
+ */
+export function validGitHubNwo(identifier: string): boolean {
+  return validGitHubNwoOrOwner(identifier, "nwo");
+}
+
+/**
+ * Checks if a string is a valid GitHub owner.
+ * @param identifier The GitHub owner
+ * @returns
+ */
+export function validGitHubOwner(identifier: string): boolean {
+  return validGitHubNwoOrOwner(identifier, "owner");
+}
+
+function validGitHubNwoOrOwner(
+  identifier: string,
+  kind: "owner" | "nwo",
+): boolean {
+  return kind === "owner"
+    ? OWNER_REGEX.test(identifier)
+    : REPO_REGEX.test(identifier);
+}
+
+/**
+ * Extracts an NOW from a GitHub URL.
+ * @param githubUrl The GitHub repository URL
+ * @return The corresponding NWO, or undefined if the URL is not valid
+ */
+export function getNwoFromGitHubUrl(githubUrl: string): string | undefined {
+  return getNwoOrOwnerFromGitHubUrl(githubUrl, "nwo");
+}
+
+/**
+ * Extracts an owner from a GitHub URL.
+ * @param githubUrl The GitHub repository URL
+ * @return The corresponding Owner, or undefined if the URL is not valid
+ */
+export function getOwnerFromGitHubUrl(githubUrl: string): string | undefined {
+  return getNwoOrOwnerFromGitHubUrl(githubUrl, "owner");
+}
+
+function getNwoOrOwnerFromGitHubUrl(
+  githubUrl: string,
+  kind: "owner" | "nwo",
+): string | undefined {
+  try {
+    const uri = new URL(githubUrl);
+    if (uri.protocol !== "https:") {
+      return;
+    }
+    if (uri.hostname !== "github.com" && uri.hostname !== "www.github.com") {
+      return;
+    }
+    const paths = uri.pathname.split("/").filter((segment: string) => segment);
+    const owner = `${paths[0]}`;
+    if (kind === "owner") {
+      return owner ? owner : undefined;
+    }
+    const nwo = `${paths[0]}/${paths[1]}`;
+    return paths[1] ? nwo : undefined;
+  } catch (e) {
+    // Ignore the error here, since we catch failures at a higher level.
+    return;
+  }
+}