// Copyright 2019 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 "pdf/accessibility.h"

#include "build/build_config.h"
#include "pdf/pdfium/pdfium_engine.h"
#include "pdf/pdfium/pdfium_test_base.h"
#include "pdf/test/test_client.h"
#include "ppapi/c/private/ppb_pdf.h"
#include "testing/gmock/include/gmock/gmock.h"

#if defined(OS_CHROMEOS)
#include "base/system/sys_info.h"
#endif

namespace chrome_pdf {

using AccessibilityTest = PDFiumTestBase;

float GetExpectedBoundsWidth(bool is_chromeos, size_t i, float expected) {
  return (is_chromeos && i == 0) ? 85.333336f : expected;
}

double GetExpectedCharWidth(bool is_chromeos, size_t i, double expected) {
  if (is_chromeos) {
    if (i == 25)
      return 13.333343;
    if (i == 26)
      return 6.666656;
  }
  return expected;
}

// NOTE: This test is sensitive to font metrics from the underlying platform.
// If changes to fonts on the system or to font code like FreeType cause this
// test to fail, please feel free to rebase the test expectations here, or
// update the GetExpected... functions above. If that becomes too much of a
// burden, consider changing the checks to just make sure the font metrics look
// sane.
TEST_F(AccessibilityTest, GetAccessibilityPage) {
  static constexpr size_t kExpectedTextRunCount = 2;
  struct {
    uint32_t len;
    double font_size;
    float bounds_x;
    float bounds_y;
    float bounds_w;
    float bounds_h;
  } static constexpr kExpectedTextRuns[] = {
      {15, 12, 26.666666f, 189.333328f, 84.000008f, 13.333344f},
      {15, 16, 28.000000f, 117.333334f, 152.000000f, 19.999992f},
  };
  static_assert(base::size(kExpectedTextRuns) == kExpectedTextRunCount,
                "Bad test expectation count");

  static constexpr size_t kExpectedCharCount = 30;
  static constexpr PP_PrivateAccessibilityCharInfo kExpectedChars[] = {
      {'H', 12}, {'e', 6.6666}, {'l', 5.3333}, {'l', 4},      {'o', 8},
      {',', 4},  {' ', 4},      {'w', 12},     {'o', 6.6666}, {'r', 6.6666},
      {'l', 4},  {'d', 9.3333}, {'!', 4},      {'\r', 0},     {'\n', 0},
      {'G', 16}, {'o', 12},     {'o', 12},     {'d', 12},     {'b', 10.6666},
      {'y', 12}, {'e', 12},     {',', 4},      {' ', 6.6666}, {'w', 16},
      {'o', 12}, {'r', 8},      {'l', 4},      {'d', 12},     {'!', 2.6666},
  };
  static_assert(base::size(kExpectedChars) == kExpectedCharCount,
                "Bad test expectation count");

  TestClient client;
  std::unique_ptr<PDFiumEngine> engine =
      InitializeEngine(&client, FILE_PATH_LITERAL("hello_world2.pdf"));
  ASSERT_TRUE(engine);

  ASSERT_EQ(2, engine->GetNumberOfPages());
  PP_PrivateAccessibilityPageInfo page_info;
  std::vector<PP_PrivateAccessibilityTextRunInfo> text_runs;
  std::vector<PP_PrivateAccessibilityCharInfo> chars;
  ASSERT_TRUE(
      GetAccessibilityInfo(engine.get(), 0, &page_info, &text_runs, &chars));
  EXPECT_EQ(0u, page_info.page_index);
  EXPECT_EQ(5, page_info.bounds.point.x);
  EXPECT_EQ(3, page_info.bounds.point.y);
  EXPECT_EQ(266, page_info.bounds.size.width);
  EXPECT_EQ(266, page_info.bounds.size.height);
  EXPECT_EQ(text_runs.size(), page_info.text_run_count);
  EXPECT_EQ(chars.size(), page_info.char_count);

#if defined(OS_CHROMEOS)
  bool is_chromeos = base::SysInfo::IsRunningOnChromeOS();
#else
  bool is_chromeos = false;
#endif

  ASSERT_EQ(kExpectedTextRunCount, text_runs.size());
  for (size_t i = 0; i < kExpectedTextRunCount; ++i) {
    const auto& expected = kExpectedTextRuns[i];
    EXPECT_EQ(expected.len, text_runs[i].len) << i;
    EXPECT_DOUBLE_EQ(expected.font_size, text_runs[i].font_size) << i;
    EXPECT_FLOAT_EQ(expected.bounds_x, text_runs[i].bounds.point.x) << i;
    EXPECT_FLOAT_EQ(expected.bounds_y, text_runs[i].bounds.point.y) << i;
    float expected_bounds_w =
        GetExpectedBoundsWidth(is_chromeos, i, expected.bounds_w);
    EXPECT_FLOAT_EQ(expected_bounds_w, text_runs[i].bounds.size.width) << i;
    EXPECT_FLOAT_EQ(expected.bounds_h, text_runs[i].bounds.size.height) << i;
    EXPECT_EQ(PP_PRIVATEDIRECTION_LTR, text_runs[i].direction);
  }

  ASSERT_EQ(kExpectedCharCount, chars.size());
  for (size_t i = 0; i < kExpectedCharCount; ++i) {
    const auto& expected = kExpectedChars[i];
    EXPECT_EQ(expected.unicode_character, chars[i].unicode_character) << i;
    double expected_char_width =
        GetExpectedCharWidth(is_chromeos, i, expected.char_width);
    EXPECT_NEAR(expected_char_width, chars[i].char_width, 0.001) << i;
  }
}

}  // namespace chrome_pdf