// Shrinks a failing input while TypeScript still parses it cleanly and the judge still fails it the same way.
// Usage: node minimize.mjs file [kind]   kind: threw (default) | chunked | ast | errors
// Deletes line ranges, then token-ish character runs (ddmin style) and prints the result as a JSON string.
import fs from "node:fs";
import { createRequire } from "node:module";
const root = new URL("../..", import.meta.url).pathname.replace(/\/$/, "");
const ts = createRequire(root + "/package.json")("typescript");
process.env.TYPESTRIP_ERASE_WASM ??= "build/erase.wasm";
const { blankSourceFile } = await import(root + "/vendor/ts-blank-space/out/index.js");
const { transformSync } = await import(root + "/src/index.js");

const kind = process.argv[3] ?? "threw";
const SK = ts.SyntaxKind;

function jsAst(code) {
  const sf = ts.createSourceFile("out.js", code, ts.ScriptTarget.ESNext, false, ts.ScriptKind.JS);
  const out = [];
  (function visit(n) {
    if (n.kind === SK.EmptyStatement || n.kind === SK.SemicolonClassElement) return;
    out.push(n.kind);
    if (ts.isIdentifier(n) || ts.isPrivateIdentifier(n) || ts.isLiteralExpression(n)) out.push(JSON.stringify(n.text));
    ts.forEachChild(n, visit);
    out.push(-1);
  })(sf);
  return out.join(",");
}

function* parts(src, n) {
  for (let i = 0; i < src.length; i += n) yield src.slice(i, i + n);
}
function chunks(src, n) {
  let out = "";
  for (const piece of transformSync(parts(src, n))) out += piece;
  return out;
}

function fails(src) {
  const sf = ts.createSourceFile("input.ts", src, ts.ScriptTarget.ESNext, false, ts.ScriptKind.TS);
  if (sf.parseDiagnostics.length) return false;
  const we = [];
  let want;
  try { want = blankSourceFile(sf, (n) => we.push(n.getStart(sf))); } catch { return false; }
  const ge = [];
  let got;
  try { got = transformSync(src, { onError: (e) => ge.push(e.start) }); } catch { return kind === "threw"; }
  if (kind === "threw") return false;
  if (kind === "ast") return jsAst(want) !== jsAst(got);
  if (kind === "errors") return jsAst(want) === jsAst(got) && we.join() !== ge.join();
  for (const n of [1, 2, 3, 5, 7, 16]) {
    try { if (chunks(src, n) !== got) return true; } catch { return true; }
  }
  return false;
}

let src = fs.readFileSync(process.argv[2], "utf8");
if (!fails(src)) { console.log("input does not fail as", kind); process.exit(1); }

function shrink(parts, join) {
  let n = 2;
  while (parts.length >= 2) {
    const size = Math.ceil(parts.length / n);
    let reduced = false;
    for (let i = 0; i < parts.length; i += size) {
      const cand = parts.slice(0, i).concat(parts.slice(i + size));
      if (fails(cand.join(join))) { parts = cand; n = Math.max(n - 1, 2); reduced = true; break; }
    }
    if (!reduced) { if (n >= parts.length) break; n = Math.min(n * 2, parts.length); }
  }
  return parts;
}

src = shrink(src.split("\n"), "\n").join("\n");
src = shrink(src.match(/\s+|\w+|./gs) ?? [], "").join("");
console.log(JSON.stringify(src));