// Copyright 2015 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "core/dom/Document.h"
#include "platform/testing/UnitTestHelpers.h"
#include "testing/gtest/include/gtest/gtest.h"
#include "web/tests/sim/SimCompositor.h"
#include "web/tests/sim/SimDisplayItemList.h"
#include "web/tests/sim/SimRequest.h"
#include "web/tests/sim/SimTest.h"

namespace blink {

class WebMeaningfulLayoutsTest : public SimTest {};

TEST_F(WebMeaningfulLayoutsTest, VisuallyNonEmptyTextCharacters) {
  SimRequest mainResource("https://example.com/index.html", "text/html");

  loadURL("https://example.com/index.html");

  mainResource.start();

  // Write 201 characters.
  const char* tenCharacters = "0123456789";
  for (int i = 0; i < 20; ++i)
    mainResource.write(tenCharacters);
  mainResource.write("!");

  mainResource.finish();

  compositor().beginFrame();

  EXPECT_EQ(1, webViewClient().visuallyNonEmptyLayoutCount());
}

TEST_F(WebMeaningfulLayoutsTest, VisuallyNonEmptyTextCharactersEventually) {
  SimRequest mainResource("https://example.com/index.html", "text/html");

  loadURL("https://example.com/index.html");

  mainResource.start();

  // Write 200 characters.
  const char* tenCharacters = "0123456789";
  for (int i = 0; i < 20; ++i)
    mainResource.write(tenCharacters);

  // Pump a frame mid-load.
  compositor().beginFrame();

  EXPECT_EQ(0, webViewClient().visuallyNonEmptyLayoutCount());

  // Write more than 200 characters.
  mainResource.write("!");

  mainResource.finish();

  // setting visually non-empty happens when the parsing finishes,
  // not as the character count goes over 200.
  compositor().beginFrame();

  EXPECT_EQ(1, webViewClient().visuallyNonEmptyLayoutCount());
}

// TODO(dglazkov): Write pixel-count and canvas-based VisuallyNonEmpty tests

TEST_F(WebMeaningfulLayoutsTest, VisuallyNonEmptyMissingPump) {
  SimRequest mainResource("https://example.com/index.html", "text/html");

  loadURL("https://example.com/index.html");

  mainResource.start();

  // Write <200 characters.
  mainResource.write("less than 200 characters.");

  compositor().beginFrame();

  mainResource.finish();

  // Even though the layout state is clean ...
  EXPECT_TRUE(document().lifecycle().state() >= DocumentLifecycle::LayoutClean);

  // We should still generate a request for another (possibly last) frame.
  EXPECT_TRUE(compositor().needsBeginFrame());

  // ... which we (the scheduler) happily provide.
  compositor().beginFrame();

  // ... which correctly signals the VisuallyNonEmpty.
  EXPECT_EQ(1, webViewClient().visuallyNonEmptyLayoutCount());
}

TEST_F(WebMeaningfulLayoutsTest, FinishedParsing) {
  SimRequest mainResource("https://example.com/index.html", "text/html");

  loadURL("https://example.com/index.html");

  mainResource.complete("content");

  compositor().beginFrame();

  EXPECT_EQ(1, webViewClient().finishedParsingLayoutCount());
}

TEST_F(WebMeaningfulLayoutsTest, FinishedLoading) {
  SimRequest mainResource("https://example.com/index.html", "text/html");

  loadURL("https://example.com/index.html");

  mainResource.complete("content");

  compositor().beginFrame();

  EXPECT_EQ(1, webViewClient().finishedLoadingLayoutCount());
}

TEST_F(WebMeaningfulLayoutsTest, FinishedParsingThenLoading) {
  SimRequest mainResource("https://example.com/index.html", "text/html");
  SimRequest imageResource("https://example.com/cat.png", "image/png");

  loadURL("https://example.com/index.html");

  mainResource.complete("<img src=cat.png>");

  compositor().beginFrame();

  EXPECT_EQ(1, webViewClient().finishedParsingLayoutCount());
  EXPECT_EQ(0, webViewClient().finishedLoadingLayoutCount());

  imageResource.complete("image data");

  // Pump the message loop to process the image loading task.
  testing::runPendingTasks();

  compositor().beginFrame();

  EXPECT_EQ(1, webViewClient().finishedParsingLayoutCount());
  EXPECT_EQ(1, webViewClient().finishedLoadingLayoutCount());
}

TEST_F(WebMeaningfulLayoutsTest, WithIFrames) {
  SimRequest mainResource("https://example.com/index.html", "text/html");
  SimRequest iframeResource("https://example.com/iframe.html", "text/html");

  loadURL("https://example.com/index.html");

  mainResource.complete("<iframe src=iframe.html></iframe>");

  compositor().beginFrame();

  EXPECT_EQ(1, webViewClient().visuallyNonEmptyLayoutCount());
  EXPECT_EQ(1, webViewClient().finishedParsingLayoutCount());
  EXPECT_EQ(0, webViewClient().finishedLoadingLayoutCount());

  iframeResource.complete("iframe data");

  // Pump the message loop to process the iframe loading task.
  testing::runPendingTasks();

  compositor().beginFrame();

  EXPECT_EQ(1, webViewClient().visuallyNonEmptyLayoutCount());
  EXPECT_EQ(1, webViewClient().finishedParsingLayoutCount());
  EXPECT_EQ(1, webViewClient().finishedLoadingLayoutCount());
}

// NoOverflowInIncrementVisuallyNonEmptyPixelCount tests fail if the number of
// pixels is calculated in 32-bit integer, because 65536 * 65536 would become 0
// if it was calculated in 32-bit and thus it would be considered as empty.
TEST_F(WebMeaningfulLayoutsTest,
       NoOverflowInIncrementVisuallyNonEmptyPixelCount) {
  SimRequest mainResource("https://example.com/test.html", "text/html");
  SimRequest svgResource("https://example.com/test.svg", "image/svg+xml");

  loadURL("https://example.com/test.html");

  mainResource.start();
  mainResource.write("<DOCTYPE html><body><img src=\"test.svg\">");
  // Run pending tasks to initiate the request to test.svg.
  testing::runPendingTasks();
  EXPECT_EQ(0, webViewClient().visuallyNonEmptyLayoutCount());

  // We serve the SVG file and check visuallyNonEmptyLayoutCount() before
  // mainResource.finish() because finishing the main resource causes
  // |FrameView::m_isVisuallyNonEmpty| to be true and
  // visuallyNonEmptyLayoutCount() to be 1 irrespective of the SVG sizes.
  svgResource.start();
  svgResource.write(
      "<svg xmlns=\"http://www.w3.org/2000/svg\" height=\"65536\" "
      "width=\"65536\"></svg>");
  svgResource.finish();
  compositor().beginFrame();
  EXPECT_EQ(1, webViewClient().visuallyNonEmptyLayoutCount());

  mainResource.finish();
}

}  // namespace blink