// Copyright 2013 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "ui/base/ime/linux/composition_text_util_pango.h"

#include <pango/pango-attributes.h>
#include <stddef.h>
#include <stdint.h>

#include <array>
#include <string>
#include <utility>

#include "base/containers/span.h"
#include "base/notreached.h"
#include "testing/gtest/include/gtest/gtest.h"
#include "ui/base/ime/composition_text.h"

namespace {

struct AttributeInfo {
  int type;
  int value;
  int start_offset;
  int end_offset;
};

struct ImeTextSpan {
  unsigned start_offset;
  unsigned end_offset;
  uint32_t underline_color;
  ui::ImeTextSpan::Thickness thickness;
  uint32_t background_color;
};

struct TestData {
  const char* text;
  const AttributeInfo attrs[10];
  const ImeTextSpan ime_text_spans[10];
};

constexpr auto kTestData = std::to_array<TestData>({
    // Normal case
    {"One Two Three",
     {{PANGO_ATTR_UNDERLINE, PANGO_UNDERLINE_SINGLE, 0, 3},
      {PANGO_ATTR_UNDERLINE, PANGO_UNDERLINE_DOUBLE, 4, 7},
      {PANGO_ATTR_BACKGROUND, 0, 4, 7},
      {PANGO_ATTR_UNDERLINE, PANGO_UNDERLINE_SINGLE, 8, 13},
      {0, 0, 0, 0}},
     {{0, 3, SK_ColorTRANSPARENT, ui::ImeTextSpan::Thickness::kThin,
       SK_ColorTRANSPARENT},
      {4, 7, SK_ColorTRANSPARENT, ui::ImeTextSpan::Thickness::kThick,
       SK_ColorTRANSPARENT},
      {8, 13, SK_ColorTRANSPARENT, ui::ImeTextSpan::Thickness::kThin,
       SK_ColorTRANSPARENT},
      {0, 0, 0, ui::ImeTextSpan::Thickness::kThin, SK_ColorTRANSPARENT}}},

    // Offset overflow.
    {"One Two Three",
     {{PANGO_ATTR_UNDERLINE, PANGO_UNDERLINE_SINGLE, 0, 3},
      {PANGO_ATTR_BACKGROUND, 0, 4, 7},
      {PANGO_ATTR_UNDERLINE, PANGO_UNDERLINE_SINGLE, 8, 20},
      {0, 0, 0, 0}},
     {{0, 3, SK_ColorTRANSPARENT, ui::ImeTextSpan::Thickness::kThin,
       SK_ColorTRANSPARENT},
      {4, 7, SK_ColorTRANSPARENT, ui::ImeTextSpan::Thickness::kThick,
       SK_ColorTRANSPARENT},
      {8, 13, SK_ColorTRANSPARENT, ui::ImeTextSpan::Thickness::kThin,
       SK_ColorTRANSPARENT},
      {0, 0, 0, ui::ImeTextSpan::Thickness::kThin, SK_ColorTRANSPARENT}}},

    // Error underline.
    {"One Two Three",
     {{PANGO_ATTR_UNDERLINE, PANGO_UNDERLINE_SINGLE, 0, 3},
      {PANGO_ATTR_UNDERLINE, PANGO_UNDERLINE_ERROR, 4, 7},
      {PANGO_ATTR_UNDERLINE, PANGO_UNDERLINE_SINGLE, 8, 13},
      {0, 0, 0, 0}},
     {{0, 3, SK_ColorTRANSPARENT, ui::ImeTextSpan::Thickness::kThin,
       SK_ColorTRANSPARENT},
      {4, 7, SK_ColorRED, ui::ImeTextSpan::Thickness::kThin,
       SK_ColorTRANSPARENT},
      {8, 13, SK_ColorTRANSPARENT, ui::ImeTextSpan::Thickness::kThin,
       SK_ColorTRANSPARENT},
      {0, 0, 0, ui::ImeTextSpan::Thickness::kThin, SK_ColorTRANSPARENT}}},

    // Default underline.
    {"One Two Three",
     {{0, 0, 0, 0}},
     {{0, 13, SK_ColorTRANSPARENT, ui::ImeTextSpan::Thickness::kThin,
       SK_ColorTRANSPARENT},
      {0, 0, 0, ui::ImeTextSpan::Thickness::kThin, SK_ColorTRANSPARENT}}},

    // Unicode, including non-BMP characters: "123你好𠀀𠀁一丁 456"
    {"123\xE4\xBD\xA0\xE5\xA5\xBD\xF0\xA0\x80\x80\xF0\xA0\x80\x81\xE4\xB8\x80"
     "\xE4\xB8\x81 456",
     {{PANGO_ATTR_UNDERLINE, PANGO_UNDERLINE_SINGLE, 0, 3},
      {PANGO_ATTR_UNDERLINE, PANGO_UNDERLINE_SINGLE, 3, 5},
      {PANGO_ATTR_BACKGROUND, 0, 5, 7},
      {PANGO_ATTR_UNDERLINE, PANGO_UNDERLINE_SINGLE, 7, 13},
      {0, 0, 0, 0}},
     {{0, 3, SK_ColorTRANSPARENT, ui::ImeTextSpan::Thickness::kThin,
       SK_ColorTRANSPARENT},
      {3, 5, SK_ColorTRANSPARENT, ui::ImeTextSpan::Thickness::kThin,
       SK_ColorTRANSPARENT},
      {5, 9, SK_ColorTRANSPARENT, ui::ImeTextSpan::Thickness::kThick,
       SK_ColorTRANSPARENT},
      {9, 15, SK_ColorTRANSPARENT, ui::ImeTextSpan::Thickness::kThin,
       SK_ColorTRANSPARENT},
      {0, 0, 0, ui::ImeTextSpan::Thickness::kThin, SK_ColorTRANSPARENT}}},
});

void CompareImeTextSpan(const ImeTextSpan& a, const ui::ImeTextSpan& b) {
  EXPECT_EQ(a.start_offset, b.start_offset);
  EXPECT_EQ(a.end_offset, b.end_offset);
  EXPECT_EQ(a.underline_color, b.underline_color);
  EXPECT_EQ(a.thickness, b.thickness);
  EXPECT_EQ(a.background_color, b.background_color);
}

TEST(CompositionTextUtilPangoTest, ExtractCompositionText) {
  for (size_t i = 0; i < std::size(kTestData); ++i) {
    const char* text = kTestData[i].text;
    base::span<const AttributeInfo> attrs = kTestData[i].attrs;
    SCOPED_TRACE(testing::Message() << "Testing:" << i
                 << " text:" << text);

    PangoAttrList* pango_attrs = pango_attr_list_new();
    for (size_t a = 0; attrs[a].type; ++a) {
      PangoAttribute* pango_attr = NULL;
      switch (attrs[a].type) {
        case PANGO_ATTR_UNDERLINE:
          pango_attr = pango_attr_underline_new(
              static_cast<PangoUnderline>(attrs[a].value));
          break;
        case PANGO_ATTR_BACKGROUND:
          pango_attr = pango_attr_background_new(0, 0, 0);
          break;
        default:
          NOTREACHED();
      }
      pango_attr->start_index =
          g_utf8_offset_to_pointer(text, attrs[a].start_offset) - text;
      pango_attr->end_index =
          g_utf8_offset_to_pointer(text, attrs[a].end_offset) - text;
      pango_attr_list_insert(pango_attrs, pango_attr);
    }

    ui::CompositionText result;
    ui::ExtractCompositionTextFromGtkPreedit(text, pango_attrs, 0, &result);

    base::span<const ImeTextSpan> ime_text_spans = kTestData[i].ime_text_spans;
    for (size_t u = 0;
         ime_text_spans[u].underline_color && u < result.ime_text_spans.size();
         ++u) {
      SCOPED_TRACE(testing::Message() << "ImeTextSpan:" << u);
      CompareImeTextSpan(ime_text_spans[u], result.ime_text_spans[u]);
    }

    pango_attr_list_unref(pango_attrs);
  }
}

}  // namespace