// The round-trip test: fixture.docx -> editor model -> .docx -> editor model,
// then diff the two models. Anything that shows up in the diff is something a
// user would lose by opening a document and pressing Save.
//
//   node test/roundtrip.mjs [some-other.docx]
import { writeFileSync, readFileSync, existsSync } from "node:fs";
import { fileURLToPath } from "node:url";
import path from "node:path";
import { loadAddonLibs, summarise, diff } from "./harness.mjs";
import { buildFixture } from "./fixture.mjs";

const here = path.dirname(fileURLToPath(import.meta.url));
const DocxEditor = loadAddonLibs();
const schema = DocxEditor.schema.build();

const input = process.argv[2];
const original = input && existsSync(input)
  ? new Uint8Array(readFileSync(input))
  : new Uint8Array(await buildFixture());
console.log(`input: ${input || "generated fixture"} (${(original.length / 1024).toFixed(1)} KB)\n`);

// --- pass 1: read ---------------------------------------------------------
const first = await DocxEditor.read.docxToDoc(original, schema);
console.log(`read: ${first.doc.childCount} top-level blocks`);
if (first.report.features.length) {
  for (const f of first.report.features) {
    console.log(`  [${f.level}] ${f.label}${f.note ? " — " + f.note : ""}`);
  }
}
if (first.warnings.length) console.log(`  warnings: ${first.warnings.join(", ")}`);

// --- pass 2: write --------------------------------------------------------
const saved = await DocxEditor.write.docToDocx(first.doc, {
  originalBytes: original,
  setup: first.setup,
  meta: first.meta,
});
console.log(`\nwrote: ${(saved.bytes.length / 1024).toFixed(1)} KB`);
if (saved.carried.length) console.log(`  carried over: ${saved.carried.join(", ")}`);
if (saved.warnings.length) console.log(`  warnings: ${saved.warnings.join(", ")}`);
const outPath = path.join(here, "roundtrip-out.docx");
writeFileSync(outPath, Buffer.from(saved.bytes));

// --- pass 3: read back ----------------------------------------------------
const second = await DocxEditor.read.docxToDoc(saved.bytes, schema);
console.log(`re-read: ${second.doc.childCount} top-level blocks`);

// --- package sanity -------------------------------------------------------
const zip = await DocxEditor.pkg.loadZip(saved.bytes);
const names = Object.keys(zip.files).sort();
const required = ["[Content_Types].xml", "_rels/.rels", "word/document.xml",
                  "word/_rels/document.xml.rels", "word/styles.xml"];
const missing = required.filter((r) => !names.includes(r));
let xmlErrors = [];
for (const name of names) {
  if (!name.endsWith(".xml") && !name.endsWith(".rels")) continue;
  try { DocxEditor.pkg.parseXml(await zip.file(name).async("string")); }
  catch (e) { xmlErrors.push(`${name}: ${e.message}`); }
}
// Every r:id the document references must exist in its rels part.
const relsDoc = DocxEditor.pkg.parseXml(await zip.file("word/_rels/document.xml.rels").async("string"));
const declared = new Set(Array.from(relsDoc.getElementsByTagName("*"))
  .filter((e) => e.localName === "Relationship").map((e) => e.getAttribute("Id")));
const docXml = await zip.file("word/document.xml").async("string");
const referenced = [...docXml.matchAll(/r:(?:id|embed|link)="([^"]+)"/g)].map((m) => m[1]);
const danglingRels = [...new Set(referenced)].filter((id) => !declared.has(id));
// Every part declared in the rels must actually be in the package.
const danglingParts = Array.from(relsDoc.getElementsByTagName("*"))
  .filter((e) => e.localName === "Relationship" && e.getAttribute("TargetMode") !== "External")
  .map((e) => "word/" + (e.getAttribute("Target") || "").replace(/^\.\//, ""))
  .filter((p) => !p.includes("://") && !names.includes(p));

console.log("\npackage sanity");
console.log(`  parts: ${names.length}`);
console.log(`  missing required: ${missing.length ? missing.join(", ") : "none"}`);
console.log(`  malformed xml: ${xmlErrors.length ? xmlErrors.join("; ") : "none"}`);
console.log(`  dangling r:ids: ${danglingRels.length ? danglingRels.join(", ") : "none"}`);
console.log(`  rels pointing at missing parts: ${danglingParts.length ? danglingParts.join(", ") : "none"}`);
for (const want of ["word/header1.xml", "word/footer1.xml", "word/footnotes.xml"]) {
  if (names.includes(want)) console.log(`  kept ${want}`);
}

// --- the diff -------------------------------------------------------------
const a = summarise(first.doc);
const b = summarise(second.doc);
const d = diff(a, b);
console.log(`\nround-trip diff: ${d.length ? d.length + " difference(s)" : "clean"}`);
for (const line of d.slice(0, 60)) console.log("  " + line);
if (d.length > 60) console.log(`  … and ${d.length - 60} more`);

writeFileSync(path.join(here, "roundtrip-a.json"), JSON.stringify(a, null, 1));
writeFileSync(path.join(here, "roundtrip-b.json"), JSON.stringify(b, null, 1));

const fatal = missing.length || xmlErrors.length || danglingRels.length || danglingParts.length;
process.exit(fatal ? 2 : d.length ? 1 : 0);