/* Any copyright is dedicated to the Public Domain.
   http://creativecommons.org/publicdomain/zero/1.0/ */

// Test diffing.

"use strict";

const {
  diffingState,
  treeMapState,
} = require("resource://devtools/client/memory/constants.js");

const TEST_URL =
  "http://example.com/browser/devtools/client/memory/test/browser/doc_steady_allocation.html";

this.test = makeMemoryTest(TEST_URL, async function ({ panel }) {
  const store = panel.panelWin.gStore;
  const { getState } = store;
  const doc = panel.panelWin.document;

  ok(!getState().diffing, "Not diffing by default.");

  // Take two snapshots.
  const takeSnapshotButton = doc.getElementById("take-snapshot");
  EventUtils.synthesizeMouseAtCenter(takeSnapshotButton, {}, panel.panelWin);
  await waitForTime(1000);
  EventUtils.synthesizeMouseAtCenter(takeSnapshotButton, {}, panel.panelWin);

  // Enable diffing mode.
  const diffButton = doc.getElementById("diff-snapshots");
  EventUtils.synthesizeMouseAtCenter(diffButton, {}, panel.panelWin);
  await waitUntilState(
    store,
    state => !!state.diffing && state.diffing.state === diffingState.SELECTING
  );
  ok(true, "Clicking the diffing button put us into the diffing state.");
  is(getDisplayedSnapshotStatus(doc), "Select the baseline snapshot");

  await waitUntilState(
    store,
    state =>
      state.snapshots.length === 2 &&
      state.snapshots[0].treeMap &&
      state.snapshots[1].treeMap &&
      state.snapshots[0].treeMap.state === treeMapState.SAVED &&
      state.snapshots[1].treeMap.state === treeMapState.SAVED
  );

  const listItems = [...doc.querySelectorAll(".snapshot-list-item")];
  is(listItems.length, 2, "Should have two snapshot list items");

  // Select the first snapshot.
  EventUtils.synthesizeMouseAtCenter(listItems[0], {}, panel.panelWin);
  await waitUntilState(
    store,
    state =>
      state.diffing.state === diffingState.SELECTING &&
      state.diffing.firstSnapshotId
  );
  is(
    getDisplayedSnapshotStatus(doc),
    "Select the snapshot to compare to the baseline"
  );

  // Select the second snapshot.
  EventUtils.synthesizeMouseAtCenter(listItems[1], {}, panel.panelWin);
  await waitUntilState(
    store,
    state => state.diffing.state === diffingState.TAKING_DIFF
  );
  ok(true, "Selecting two snapshots for diffing triggers computing the diff");

  // .startsWith because the ellipsis is lost in translation.
  ok(getDisplayedSnapshotStatus(doc).startsWith("Computing difference"));

  await waitUntilState(
    store,
    state => state.diffing.state === diffingState.TOOK_DIFF
  );
  ok(true, "And that diff is computed successfully");
  is(getDisplayedSnapshotStatus(doc), null, "No status text anymore");
  ok(
    doc.querySelector(".heap-tree-item"),
    "And instead we should be showing the tree"
  );
});