// Collect every image referenced by an Obsidian embed (![[...]]) in the
// garden content and copy it to public/assets/ flat by basename — matching
// the /assets/<name> URLs the remark plugin emits. Resolution order:
// Digital_Garden first, then the wider vault (some embeds point at files
// that live outside the published folder; the live Quartz site 404s those —
// we fix them, but loudly, so stray references are visible).
import fs from 'node:fs';
import path from 'node:path';
import { fileURLToPath } from 'node:url';
import {
  CONTENT_DIR,
  VAULT_ROOT,
  walkMarkdown,
} from '../src/lib/quartz-compat.mjs';

const OUT_DIR = path.join(
  path.dirname(fileURLToPath(import.meta.url)),
  '..',
  'public',
  'assets',
);
const EMBED_RE = /!\[\[([^\]|]+?\.(?:png|jpe?g|gif|svg|webp))(?:\|[^\]]*)?\]\]/gi;
const MD_IMG_RE = /!\[[^\]]*\]\(([^)\s]+?\.(?:png|jpe?g|gif|svg|webp))\)/gi;

function walkFiles(dir) {
  const out = [];
  for (const ent of fs.readdirSync(dir, { withFileTypes: true })) {
    if (ent.name.startsWith('.')) continue;
    const full = path.join(dir, ent.name);
    if (ent.isDirectory()) out.push(...walkFiles(full));
    else out.push(full);
  }
  return out;
}

// referenced image names (basename, as Obsidian resolves vault-wide)
const wanted = new Map(); // lowercase basename -> name as referenced
for (const rel of walkMarkdown(CONTENT_DIR)) {
  const text = fs.readFileSync(path.join(CONTENT_DIR, rel), 'utf8');
  for (const m of text.matchAll(EMBED_RE)) {
    const name = m[1].split('/').pop().trim();
    wanted.set(name.toLowerCase(), name);
  }
  for (const m of text.matchAll(MD_IMG_RE)) {
    if (/^(?:[a-z]+:)?\/\//i.test(m[1])) continue;
    const name = decodeURIComponent(m[1]).split('/').pop().trim();
    wanted.set(name.toLowerCase(), name);
  }
}

// index every file in the vault by lowercase basename
const inDG = new Map();
const inVault = new Map();
for (const f of walkFiles(VAULT_ROOT)) {
  const key = path.basename(f).toLowerCase();
  if (f.startsWith(CONTENT_DIR + path.sep)) {
    if (!inDG.has(key)) inDG.set(key, f);
  } else if (!inVault.has(key)) {
    inVault.set(key, f);
  }
}

fs.rmSync(OUT_DIR, { recursive: true, force: true });
fs.mkdirSync(OUT_DIR, { recursive: true });

let copied = 0;
let missing = 0;
for (const [key, name] of wanted) {
  const src = inDG.get(key) ?? inVault.get(key);
  if (!src) {
    console.warn(`copy-assets: UNRESOLVED image embed: ${name}`);
    missing++;
    continue;
  }
  if (!inDG.has(key)) {
    console.warn(
      `copy-assets: ${name} lives outside Digital_Garden (${path.relative(VAULT_ROOT, src)})`,
    );
  }
  fs.copyFileSync(src, path.join(OUT_DIR, name));
  copied++;
}

console.log(`copy-assets: ${copied} copied, ${missing} unresolved -> ${OUT_DIR}`);
if (missing) process.exitCode = 0; // warn, don't fail the build