#!/usr/bin/env node
/*
 * scripts/mirror-ee.js — runs at predev/prebuild.
 *
 * Next.js Pages Router only routes files physically inside pages/. Premium pages/APIs
 * live in ee/pages/** so they can be stripped from the public build, but they must be
 * COPIED into pages/** for Next to see them during dev/build in the private repo.
 *
 * This script copies ee/pages/** → pages/** and records every file it wrote in
 * pages/.ee-mirror-manifest.json. It also writes a generated pages/.gitignore listing
 * every mirrored path — git reads nested .gitignore files natively, so the copies are
 * never tracked in either repo and pages/ stays clean in git. Source of truth is ee/pages.
 *
 * When ee/ is absent (public build), this is a no-op. See docs/OPEN_CORE.md.
 *
 * Everything else in ee/ (lib code) is imported in place via @/ee — NOT mirrored.
 */
const fs = require("fs");
const path = require("path");

const ROOT = path.resolve(__dirname, "..");
const EE_PAGES = path.join(ROOT, "ee", "pages");
const PAGES = path.join(ROOT, "pages");
const MANIFEST = path.join(PAGES, ".ee-mirror-manifest.json");
const NESTED_IGNORE = path.join(PAGES, ".gitignore");

function cleanPrevious() {
  // Remove files written by a previous mirror run so renames/deletions in ee/pages
  // don't leave stale routes behind.
  if (!fs.existsSync(MANIFEST)) return;
  try {
    const prev = JSON.parse(fs.readFileSync(MANIFEST, "utf8"));
    for (const rel of prev.files ?? []) {
      const p = path.join(PAGES, rel);
      if (fs.existsSync(p)) fs.rmSync(p);
    }
    fs.rmSync(MANIFEST);
    if (fs.existsSync(NESTED_IGNORE)) fs.rmSync(NESTED_IGNORE);
  } catch {
    /* ignore a corrupt manifest — fresh mirror below overwrites cleanly */
  }
}

function walk(dir, base = dir) {
  const out = [];
  for (const entry of fs.readdirSync(dir, { withFileTypes: true })) {
    const abs = path.join(dir, entry.name);
    if (entry.isDirectory()) out.push(...walk(abs, base));
    else out.push(path.relative(base, abs));
  }
  return out;
}

function main() {
  cleanPrevious();

  if (!fs.existsSync(EE_PAGES)) {
    console.log("[mirror-ee] no ee/pages (public build or none yet) — nothing to mirror");
    return;
  }

  const files = walk(EE_PAGES);
  for (const rel of files) {
    const src = path.join(EE_PAGES, rel);
    const dst = path.join(PAGES, rel);
    fs.mkdirSync(path.dirname(dst), { recursive: true });
    fs.copyFileSync(src, dst);
  }

  fs.writeFileSync(
    MANIFEST,
    JSON.stringify({ generatedAt: new Date().toISOString(), files }, null, 2)
  );

  // Nested .gitignore so the mirrored copies are never tracked. Git reads this natively.
  // Paths are POSIX-style and relative to pages/. The manifest + this file ignore themselves.
  // IMPORTANT: gitignore treats [ ] * ? as glob metacharacters, so Next's dynamic-route
  // segments like [replyId] must be backslash-escaped or the pattern won't match the literal
  // directory (leaving the mirrored copy tracked). Escape them.
  const esc = (p) => p.replace(/([[\]*?])/g, "\\$1");
  const ignoreBody = [
    "# GENERATED by scripts/mirror-ee.js — do not edit. Lists premium pages mirrored",
    "# from ee/pages/. Source of truth is ee/pages/**. See docs/OPEN_CORE.md.",
    ".gitignore",
    ".ee-mirror-manifest.json",
    ...files.map((f) => "/" + esc(f.split(path.sep).join("/"))),
    "",
  ].join("\n");
  fs.writeFileSync(NESTED_IGNORE, ignoreBody);

  console.log(`[mirror-ee] mirrored ${files.length} premium page(s) into pages/`);
}

main();