// Copyright 2016 PDFium 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/fxcrt/fx_string.h"
#include "public/fpdf_structtree.h"
#include "testing/embedder_test.h"
#include "testing/test_support.h"
#include "third_party/base/optional.h"

class FPDFStructTreeEmbeddertest : public EmbedderTest {};

TEST_F(FPDFStructTreeEmbeddertest, GetAltText) {
  ASSERT_TRUE(OpenDocument("tagged_alt_text.pdf"));
  FPDF_PAGE page = LoadPage(0);
  ASSERT_TRUE(page);

  {
    ScopedFPDFStructTree struct_tree(FPDF_StructTree_GetForPage(page));
    ASSERT_TRUE(struct_tree);
    ASSERT_EQ(1, FPDF_StructTree_CountChildren(struct_tree.get()));

    FPDF_STRUCTELEMENT element =
        FPDF_StructTree_GetChildAtIndex(struct_tree.get(), -1);
    EXPECT_EQ(nullptr, element);
    element = FPDF_StructTree_GetChildAtIndex(struct_tree.get(), 1);
    EXPECT_EQ(nullptr, element);
    element = FPDF_StructTree_GetChildAtIndex(struct_tree.get(), 0);
    ASSERT_NE(nullptr, element);
    EXPECT_EQ(-1, FPDF_StructElement_GetMarkedContentID(element));
    EXPECT_EQ(0U, FPDF_StructElement_GetAltText(element, nullptr, 0));

    ASSERT_EQ(1, FPDF_StructElement_CountChildren(element));
    FPDF_STRUCTELEMENT child_element =
        FPDF_StructElement_GetChildAtIndex(element, -1);
    EXPECT_EQ(nullptr, child_element);
    child_element = FPDF_StructElement_GetChildAtIndex(element, 1);
    EXPECT_EQ(nullptr, child_element);
    child_element = FPDF_StructElement_GetChildAtIndex(element, 0);
    ASSERT_NE(nullptr, child_element);
    EXPECT_EQ(-1, FPDF_StructElement_GetMarkedContentID(child_element));
    EXPECT_EQ(0U, FPDF_StructElement_GetAltText(child_element, nullptr, 0));

    ASSERT_EQ(1, FPDF_StructElement_CountChildren(child_element));
    FPDF_STRUCTELEMENT gchild_element =
        FPDF_StructElement_GetChildAtIndex(child_element, -1);
    EXPECT_EQ(nullptr, gchild_element);
    gchild_element = FPDF_StructElement_GetChildAtIndex(child_element, 1);
    EXPECT_EQ(nullptr, gchild_element);
    gchild_element = FPDF_StructElement_GetChildAtIndex(child_element, 0);
    ASSERT_NE(nullptr, gchild_element);
    EXPECT_EQ(-1, FPDF_StructElement_GetMarkedContentID(gchild_element));
    ASSERT_EQ(24U, FPDF_StructElement_GetAltText(gchild_element, nullptr, 0));

    unsigned short buffer[12];
    memset(buffer, 0, sizeof(buffer));
    // Deliberately pass in a small buffer size to make sure |buffer| remains
    // untouched.
    ASSERT_EQ(24U, FPDF_StructElement_GetAltText(gchild_element, buffer, 1));
    for (size_t i = 0; i < FX_ArraySize(buffer); ++i)
      EXPECT_EQ(0U, buffer[i]);

    EXPECT_EQ(-1, FPDF_StructElement_GetMarkedContentID(gchild_element));
    ASSERT_EQ(24U, FPDF_StructElement_GetAltText(gchild_element, buffer,
                                                 sizeof(buffer)));
    const wchar_t kExpected[] = L"Black Image";
    EXPECT_EQ(WideString(kExpected),
              WideString::FromUTF16LE(buffer, FXSYS_len(kExpected)));

    ASSERT_EQ(1, FPDF_StructElement_CountChildren(gchild_element));
    FPDF_STRUCTELEMENT ggchild_element =
        FPDF_StructElement_GetChildAtIndex(gchild_element, 0);
    EXPECT_EQ(nullptr, ggchild_element);
  }

  UnloadPage(page);
}

TEST_F(FPDFStructTreeEmbeddertest, GetMarkedContentID) {
  ASSERT_TRUE(OpenDocument("marked_content_id.pdf"));
  FPDF_PAGE page = LoadPage(0);
  ASSERT_TRUE(page);

  {
    ScopedFPDFStructTree struct_tree(FPDF_StructTree_GetForPage(page));
    ASSERT_TRUE(struct_tree);
    ASSERT_EQ(1, FPDF_StructTree_CountChildren(struct_tree.get()));

    FPDF_STRUCTELEMENT element =
        FPDF_StructTree_GetChildAtIndex(struct_tree.get(), 0);
    EXPECT_EQ(0, FPDF_StructElement_GetMarkedContentID(element));
  }

  UnloadPage(page);
}

TEST_F(FPDFStructTreeEmbeddertest, GetType) {
  ASSERT_TRUE(OpenDocument("tagged_alt_text.pdf"));
  FPDF_PAGE page = LoadPage(0);
  ASSERT_TRUE(page);

  {
    ScopedFPDFStructTree struct_tree(FPDF_StructTree_GetForPage(page));
    ASSERT_TRUE(struct_tree);
    ASSERT_EQ(1, FPDF_StructTree_CountChildren(struct_tree.get()));

    FPDF_STRUCTELEMENT element =
        FPDF_StructTree_GetChildAtIndex(struct_tree.get(), 0);
    ASSERT_NE(nullptr, element);

    unsigned short buffer[12];
    memset(buffer, 0, sizeof(buffer));
    // Deliberately pass in a small buffer size to make sure |buffer| remains
    // untouched.
    ASSERT_EQ(18U, FPDF_StructElement_GetType(element, buffer, 1));
    for (size_t i = 0; i < FX_ArraySize(buffer); ++i)
      EXPECT_EQ(0U, buffer[i]);

    ASSERT_EQ(18U, FPDF_StructElement_GetType(element, buffer, sizeof(buffer)));
    const wchar_t kExpected[] = L"Document";
    EXPECT_EQ(WideString(kExpected),
              WideString::FromUTF16LE(buffer, FXSYS_len(kExpected)));
  }

  UnloadPage(page);
}