// Copyright 2020 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 "components/omnibox/browser/inline_autocompletion_util.h"

#include <stddef.h>

#include "base/strings/utf_string_conversions.h"
#include "testing/gmock/include/gmock/gmock.h"
#include "testing/gtest/include/gtest/gtest.h"

namespace {

TEST(InlineAutocompletionUtilTest, FindAtWordbreak) {
  // Should find the first wordbreak occurrence.
  EXPECT_EQ(FindAtWordbreak(u"prefixmatch wordbreak_match", u"match"), 22u);

  // Should return npos when no occurrences exist.
  EXPECT_EQ(FindAtWordbreak(u"prefixmatch", u"match"), std::string::npos);

  // Should skip occurrences before |search_start|.
  EXPECT_EQ(FindAtWordbreak(u"match match", u"match", 1), 6u);
}

TEST(InlineAutocompletionUtilTest, FindWordsSequentiallyAtWordbreak) {
  using pair = std::pair<size_t, size_t>;

  // Occurrences must be sequential.
  EXPECT_THAT(FindWordsSequentiallyAtWordbreak(u"a b c", u"a c"),
              testing::ElementsAre(pair{0, 1}, pair{1, 2}, pair{4, 5}));
  EXPECT_THAT(FindWordsSequentiallyAtWordbreak(u"c b a", u"a b"),
              testing::ElementsAre());
  EXPECT_THAT(FindWordsSequentiallyAtWordbreak(u"b a b", u"a b"),
              testing::ElementsAre(pair{2, 3}, pair{3, 4}, pair{4, 5}));

  // Occurrences must be at word breaks.
  EXPECT_THAT(FindWordsSequentiallyAtWordbreak(u"a b-c", u"a c"),
              testing::ElementsAre(pair{0, 1}, pair{1, 2}, pair{4, 5}));
  EXPECT_THAT(FindWordsSequentiallyAtWordbreak(u"a bc", u"a c"),
              testing::ElementsAre());
  EXPECT_THAT(FindWordsSequentiallyAtWordbreak(u"a bc c", u"a c"),
              testing::ElementsAre(pair{0, 1}, pair{1, 2}, pair{5, 6}));

  // Whitespaces must also match
  EXPECT_THAT(FindWordsSequentiallyAtWordbreak(u"a-c", u"a c"),
              testing::ElementsAre());
  EXPECT_THAT(FindWordsSequentiallyAtWordbreak(u"a c", u"a c "),
              testing::ElementsAre());
  EXPECT_THAT(FindWordsSequentiallyAtWordbreak(u"a -c", u"a c"),
              testing::ElementsAre(pair{0, 1}, pair{1, 2}, pair{3, 4}));
  EXPECT_THAT(FindWordsSequentiallyAtWordbreak(u"a- c", u"a c"),
              testing::ElementsAre(pair{0, 1}, pair{2, 3}, pair{3, 4}));
  EXPECT_THAT(FindWordsSequentiallyAtWordbreak(u"a c c", u"a  c"),
              testing::ElementsAre());
  EXPECT_THAT(FindWordsSequentiallyAtWordbreak(u"a c  c", u"a  c"),
              testing::ElementsAre(pair{0, 1}, pair{3, 5}, pair{5, 6}));
}

TEST(InlineAutocompletionUtilTest, TermMatchesToSelections) {
  // Empty |ranges| in empty |length|.
  EXPECT_THAT(TermMatchesToSelections(0, {}), testing::ElementsAre());
  // Empty |ranges| in non-empty |length|. 12345 -> [12345]
  EXPECT_THAT(TermMatchesToSelections(5, {}),
              testing::ElementsAre(gfx::Range{5, 0}));
  // Single empty range in |ranges|.  12|345 -> [12][345]
  EXPECT_THAT(TermMatchesToSelections(5, {{2, 2}}),
              testing::ElementsAre(gfx::Range{5, 2}, gfx::Range{2, 0}));
  // Multiple empty ranges in |ranges|.  1|2|3|4|5 -> [1234][5]
  EXPECT_THAT(TermMatchesToSelections(5, {{1, 1}, {2, 2}, {3, 3}, {4, 4}}),
              testing::ElementsAre(gfx::Range{5, 4}, gfx::Range{4, 0}));
  // Single range in |ranges|. 12[3]45 -> [12]3[45]
  EXPECT_THAT(TermMatchesToSelections(5, {{2, 3}}),
              testing::ElementsAre(gfx::Range{5, 3}, gfx::Range{2, 0}));
  // Single range in |ranges| spanning all of |length|. [12345] -> 12345|
  EXPECT_THAT(TermMatchesToSelections(5, {{0, 5}}),
              testing::ElementsAre(gfx::Range{5, 5}));
  // Multiple ranges in |ranges|, including adjacent and empty ranges.
  // 1[23][45]6[7][8]9 -> [1]2345[6]78[9]
  EXPECT_THAT(TermMatchesToSelections(9, {{1, 3}, {3, 5}, {6, 7}, {7, 8}}),
              testing::ElementsAre(gfx::Range{9, 8}, gfx::Range{6, 5},
                                   gfx::Range{1, 0}));
  // |ranges| ending at |length| and starting 0.
  // [123][45]6[789] -> 12345[6]789|
  EXPECT_THAT(TermMatchesToSelections(9, {{0, 3}, {3, 5}, {6, 9}}),
              testing::ElementsAre(gfx::Range{9, 9}, gfx::Range{6, 5}));
}

}  // namespace