import test from "node:test";
import assert from "node:assert/strict";

import { CmapHistory } from "../static/js/cmap/controller/cmap-history.js";

function history(initial = "one") {
  let value = initial;
  const changes = [];
  const instance = new CmapHistory({
    snapshot: () => value,
    restore: (snapshot) => { value = snapshot; },
    onChange: (change) => changes.push(change),
    limit: 2
  });
  return {
    instance,
    changes,
    get value() { return value; },
    set value(next) { value = next; }
  };
}

test("CmapHistory commits, undoes and redoes serialized state", () => {
  const state = history();
  state.instance.reset();
  state.value = "two";
  assert.equal(state.instance.commit(), true);
  state.value = "three";
  assert.equal(state.instance.commit(), true);

  assert.equal(state.instance.undo(), true);
  assert.equal(state.value, "two");
  assert.equal(state.instance.redo(), true);
  assert.equal(state.value, "three");
  assert.equal(state.instance.canUndo(), true);
  assert.equal(state.instance.canRedo(), false);
});

test("CmapHistory replaces a document as one undo operation", () => {
  const state = history();
  state.instance.reset();
  state.instance.replace(() => { state.value = "replacement"; });

  assert.equal(state.value, "replacement");
  assert.equal(state.instance.undo(), true);
  assert.equal(state.value, "one");
  assert.ok(state.changes.length > 0);
});