import { test } from "node:test";
import assert from "node:assert/strict";
import { readFileSync, readdirSync, writeFileSync, existsSync, mkdirSync } from "node:fs";
import { parseDocx } from "../server/parser.js";
import { diagnose } from "../server/diagnostics.js";
import { snapshotOf, diffLines } from "../scripts/snapshot-lines.js";

// Every fixture parsed and compared line by line with test/snapshots/<name>.txt, together with
// the cells diagnostics flags. After an intended parser change: UPDATE_SNAPSHOTS=1 npm test,
// then read the diff of test/snapshots/ before committing it.
const fixtures = new URL("./fixtures/", import.meta.url);
const snapshots = new URL("./snapshots/", import.meta.url);
const update = process.env.UPDATE_SNAPSHOTS === "1";
// The bell schedule and the week table are calendar documents, not timetables.
const calendars = new Set(["bells.docx", "weeks.docx"]);

for (const file of readdirSync(fixtures).filter((f) => f.endsWith(".docx") && !calendars.has(f)).sort()) {
  test(`снимок разбора: ${file}`, () => {
    const meta = existsSync(new URL(`${file}.json`, fixtures))
      ? JSON.parse(readFileSync(new URL(`${file}.json`, fixtures), "utf8"))
      : {};
    const schedule = parseDocx(readFileSync(new URL(file, fixtures)), {
      name: meta.name || file,
      modified: meta.modified,
    });
    const lines = [
      ...snapshotOf(schedule),
      ...diagnose(schedule).map((p) => `! ${p.code} | ${(p.raw || p.groups?.join(",") || "").replace(/\s+/g, " ")}`),
    ];
    const target = new URL(file.replace(/\.docx$/, ".txt"), snapshots);
    if (update || !existsSync(target)) {
      mkdirSync(snapshots, { recursive: true });
      writeFileSync(target, lines.join("\n") + "\n");
      return;
    }
    const saved = readFileSync(target, "utf8").trimEnd().split("\n");
    const { removed, added } = diffLines(saved, lines);
    assert.ok(
      !removed.length && !added.length,
      `Разбор ${file} изменился (UPDATE_SNAPSHOTS=1 npm test, если так и задумано):\n` +
        [...removed.map((l) => `  − ${l}`), ...added.map((l) => `  + ${l}`)].join("\n"),
    );
  });
}