Refactor

2 files changed, 103 insertions, 151 deletions

diff --git a/cgithub/src/index.ts b/cgithub/src/index.ts
index 525ac74..fcd0069 100644
--- a/cgithub/src/index.ts
+++ b/cgithub/src/index.ts
@@ -14,45 +14,15 @@ const eta = new Eta({ views: path.join(__dirname, "..", "views") });
 app.use("/static/*", serveStatic({ root: path.join(__dirname, "..") }));
 
 app.get("/:owner/:repo/tree/:branch/:path{.*}?", async (c) => {
-  try {
-    const owner = c.req.param("owner");
-    const repo = c.req.param("repo");
-    const branch = c.req.param("branch");
-    const path = c.req.param("path") || "";
-
-    const data = await getGitHubTree(owner, repo, branch, path);
-    const html = await eta.renderAsync("tree.eta", data);
-
-    return c.html(html);
-  } catch (error) {
-    const errorMessage =
-      error instanceof Error ? error.message : "Unknown error";
-    return c.html(
-      `<html><body><h1>Error</h1><p>${errorMessage}</p></body></html>`,
-      500,
-    );
-  }
+  const { owner, repo, branch, path = "" } = c.req.param();
+  const data = await getGitHubTree(owner, repo, branch, path);
+  return c.html(await eta.renderAsync("tree.eta", data));
 });
 
 app.get("/:owner/:repo/blob/:branch/:path{.*}", async (c) => {
-  try {
-    const owner = c.req.param("owner");
-    const repo = c.req.param("repo");
-    const branch = c.req.param("branch");
-    const path = c.req.param("path");
-
-    const data = await getGitHubBlob(owner, repo, branch, path);
-    const html = await eta.renderAsync("blob.eta", data);
-
-    return c.html(html);
-  } catch (error) {
-    const errorMessage =
-      error instanceof Error ? error.message : "Unknown error";
-    return c.html(
-      `<html><body><h1>Error</h1><p>${errorMessage}</p></body></html>`,
-      500,
-    );
-  }
+  const { owner, repo, branch, path } = c.req.param();
+  const data = await getGitHubBlob(owner, repo, branch, path);
+  return c.html(await eta.renderAsync("blob.eta", data));
 });
 
 if (process.env.LISTEN_FDS === "1") {
diff --git a/cgithub/src/scraper.ts b/cgithub/src/scraper.ts
index fa8d655..d6702cc 100644
--- a/cgithub/src/scraper.ts
+++ b/cgithub/src/scraper.ts
@@ -1,146 +1,137 @@
-export interface GitHubTreeItem {
+interface TreeItem {
+  contentType: "directory" | "file";
   name: string;
   path: string;
-  contentType: "directory" | "file";
 }
 
-export interface GitHubTree {
-  path: string;
-  branch: string;
-  items: GitHubTreeItem[];
+interface RawPayload {
   repo: {
+    ownerLogin: string;
     name: string;
-    owner: string;
-    isPublic: boolean;
+  };
+  refInfo: { name: string };
+  path: string;
+  tree?: {
+    items: TreeItem[];
+  };
+  blob?: {
+    language?: string;
+    rawLines?: string[];
+    highlightedLines?: {
+      text?: string;
+    }[];
+    size: number;
   };
 }
 
-export interface GitHubBlob {
-  path: string;
-  branch: string;
-  content: string;
-  rawContent: string;
-  language: string | null;
-  size: number;
+interface GitHubCommon {
   repo: {
-    name: string;
     owner: string;
-    isPublic: boolean;
+    name: string;
   };
+  branch: string;
+  path: string;
 }
 
-export async function getGitHubTree(
-  owner: string,
-  repo: string,
-  branch: string,
-  path: string,
-): Promise<GitHubTree> {
-  const url = `https://github.com/${owner}/${repo}/tree/${branch}/${path}`;
+export interface GitHubTree extends GitHubCommon {
+  items: TreeItem[];
+}
+
+export interface GitHubBlob extends GitHubCommon {
+  language: string | null;
+  size: number;
+  content: string;
+  rawContent: string;
+}
 
+async function fetchGitHubPage(path: string): Promise<string> {
   // GitHub throttles/blocks requests without realistic browser headers.
   // These headers make the request appear as a standard browser visit.
-  const response = await fetch(url, {
-    headers: {
-      "User-Agent":
-        "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/131.0.0.0 Safari/537.36",
-      Accept:
-        "text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8",
-      "Accept-Language": "en-US,en;q=0.5",
-    },
-  });
-  const html = await response.text();
+  const headers = {
+    "User-Agent":
+      "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/131.0.0.0 Safari/537.36",
+    Accept:
+      "text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8",
+    "Accept-Language": "en-US,en;q=0.5",
+  };
+  const response = await fetch(`https://github.com/${path}`, { headers });
+  return response.text();
+}
 
-  // GitHub uses different formats for root vs subdirectories.
-  let payload;
+function parsePayload(
+  html: string,
+  dataTarget: string,
+  prop: string[],
+): RawPayload | null {
+  const regex = new RegExp(
+    `<script type="application/json" data-target="${dataTarget}">([^<]+)</script>`,
+    "g",
+  );
 
-  // Try root format first.
-  const rootFormatMatches = [
-    ...html.matchAll(
-      /<script type="application\/json" data-target="react-partial\.embeddedData">([^<]+)<\/script>/g,
-    ),
-  ];
-  for (const match of rootFormatMatches) {
+  match: for (const match of html.matchAll(regex)) {
+    let data;
     try {
-      const data = JSON.parse(match[1]);
-      if (data.props?.initialPayload?.tree) {
-        payload = data.props.initialPayload;
-        break;
-      }
-    } catch (e) {
+      data = JSON.parse(match[1]);
+    } catch {
       continue;
     }
-  }
-
-  // Try subdirectory format.
-  if (!payload) {
-    const dirFormatMatch = html.match(
-      /<script type="application\/json" data-target="react-app\.embeddedData">([^<]+)<\/script>/,
-    );
-    if (dirFormatMatch) {
-      try {
-        const data = JSON.parse(dirFormatMatch[1]);
-        if (data.payload?.tree) {
-          payload = data.payload;
-        }
-      } catch (e) {
-        // Skip invalid JSON
-      }
+    for (const key of prop) {
+      data = data[key];
+      if (data === undefined) continue match;
     }
+    return data;
   }
+  return null;
+}
 
-  if (!payload) {
-    throw new Error("Could not find tree data in embedded JSON");
-  }
-
+function extractGitHub<T>(payload: RawPayload, extra: T): GitHubCommon & T {
   return {
-    path: payload.path,
-    branch: payload.refInfo.name,
-    items: payload.tree.items,
     repo: {
-      name: payload.repo.name,
       owner: payload.repo.ownerLogin,
-      isPublic: payload.repo.public,
+      name: payload.repo.name,
     },
+    branch: payload.refInfo.name,
+    path: payload.path,
+    ...extra,
   };
 }
 
-export async function getGitHubBlob(
+export async function getGitHubTree(
   owner: string,
   repo: string,
   branch: string,
   path: string,
-): Promise<GitHubBlob> {
-  const url = `https://github.com/${owner}/${repo}/blob/${branch}/${path}`;
-
-  const response = await fetch(url, {
-    headers: {
-      "User-Agent":
-        "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/131.0.0.0 Safari/537.36",
-      Accept:
-        "text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8",
-      "Accept-Language": "en-US,en;q=0.5",
-    },
-  });
-  const html = await response.text();
+): Promise<GitHubTree> {
+  const html = await fetchGitHubPage(`${owner}/${repo}/tree/${branch}/${path}`);
 
-  // GitHub embeds file data in a JSON script tag
-  let payload;
+  // GitHub uses different formats for root vs subdirectories.
+  const payload =
+    // Root directory format.
+    parsePayload(html, "react-partial.embeddedData", [
+      "props",
+      "initialPayload",
+    ]) ||
+    // Subdirectory format.
+    parsePayload(html, "react-app.embeddedData", ["payload"]);
 
-  const match = html.match(
-    /<script type="application\/json" data-target="react-app\.embeddedData">([^<]+)<\/script>/,
-  );
-  if (match) {
-    try {
-      const data = JSON.parse(match[1]);
-      if (data.payload?.blob) {
-        payload = data.payload;
-      }
-    } catch (e) {
-      // Skip invalid JSON
-    }
+  if (payload?.tree === undefined) {
+    throw new Error("Could not find tree data in embedded JSON");
   }
 
-  if (!payload) {
+  return extractGitHub(payload, { items: payload.tree.items });
+}
+
+export async function getGitHubBlob(
+  owner: string,
+  repo: string,
+  branch: string,
+  path: string,
+): Promise<GitHubBlob> {
+  const html = await fetchGitHubPage(`${owner}/${repo}/blob/${branch}/${path}`);
+
+  const payload = parsePayload(html, "react-app.embeddedData", ["payload"]);
+
+  if (payload?.blob === undefined) {
     throw new Error("Could not find blob data in embedded JSON");
   }
 
@@ -148,21 +139,12 @@ export async function getGitHubBlob(
   const rawLines = blob.rawLines || [];
   const rawContent = rawLines.join("\n");
   const highlightedLines = blob.highlightedLines || [];
-  const content = highlightedLines
-    .map((line: any) => line.text || "")
-    .join("\n");
+  const content = highlightedLines.map((line) => line.text || "").join("\n");
 
-  return {
-    path: payload.path,
-    branch: payload.refInfo.name,
+  return extractGitHub(payload, {
     content: content || rawContent,
     rawContent,
     language: blob.language || null,
     size: blob.size,
-    repo: {
-      name: payload.repo.name,
-      owner: payload.repo.ownerLogin,
-      isPublic: payload.repo.public,
-    },
-  };
+  });
 }