/**
 * Patch: make store-github updateFile fall back to create when the file doesn't exist.
 *
 * Problem: when a post was created in MongoDB but the Gitea write failed (e.g. due to a
 * previous 401), IndieKit sees the post as existing and calls updateFile() on re-publish.
 * updateFile() reads the file first to get its SHA, gets a 404, and throws instead of
 * creating the file.
 *
 * Fix: if the read step returns "Not Found", proceed without a SHA. The Gitea Contents API
 * (same as GitHub API) creates a new file when PUT is called without a sha field.
 * Also fixes sha: false being sent (invalid) — now only sent when we actually have a SHA.
 */

import { readFile, writeFile, access } from "node:fs/promises";

const TARGET = "node_modules/@indiekit/store-github/index.js";
const MARKER = "// [patch] store-github-update-fallback";

const OLD_READ = `    let readResponse;
    try {
      debug(\`Try reading file \${filePath} in repo \${repo}, branch \${branch}\`);
      readResponse = await this.#client(\`\${filePath}?ref=\${branch}\`);
    } catch (error) {
      const message = crudErrorMessage({
        error,
        operation: "read",
        filePath,
        repo,
        branch,
      });
      debug(message);
      throw new Error(message);
    }

    const { sha } = await readResponse.json();`;

const NEW_READ = `    let sha; ${MARKER}
    try {
      debug(\`Try reading file \${filePath} in repo \${repo}, branch \${branch}\`);
      const readResponse = await this.#client(\`\${filePath}?ref=\${branch}\`);
      const readJson = await readResponse.json();
      sha = readJson.sha;
    } catch (error) {
      if (error.message && error.message.includes("Not Found")) {
        // File doesn't exist yet — will create it via PUT without sha
        debug(\`File \${filePath} not found in repo \${repo} — will create instead of update\`);
        sha = undefined;
      } else {
        const message = crudErrorMessage({
          error,
          operation: "read",
          filePath,
          repo,
          branch,
        });
        debug(message);
        throw new Error(message);
      }
    }`;

const OLD_SHA = `        sha: sha || false,`;
const NEW_SHA = `        ...(sha ? { sha } : {}), ${MARKER}`;

async function exists(p) {
  try { await access(p); return true; } catch { return false; }
}

if (!(await exists(TARGET))) {
  console.log(`[postinstall] store-github-update-fallback: target not found, skipping`);
  process.exit(0);
}

const source = await readFile(TARGET, "utf8");

if (source.includes(MARKER)) {
  console.log("[postinstall] store-github-update-fallback: already patched");
  process.exit(0);
}

if (!source.includes(OLD_READ)) {
  console.warn("[postinstall] store-github-update-fallback: read snippet not found — skipping");
  process.exit(0);
}

if (!source.includes(OLD_SHA)) {
  console.warn("[postinstall] store-github-update-fallback: sha snippet not found — skipping");
  process.exit(0);
}

const updated = source
  .replace(OLD_READ, NEW_READ)
  .replace(OLD_SHA, NEW_SHA);

await writeFile(TARGET, updated, "utf8");
console.log(`[postinstall] store-github-update-fallback: patched ${TARGET}`);