// Copyright 2014 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.

#ifndef CONTENT_WEB_TEST_RENDERER_WEB_TEST_SPELL_CHECKER_H_
#define CONTENT_WEB_TEST_RENDERER_WEB_TEST_SPELL_CHECKER_H_

#include <vector>

#include "third_party/blink/public/platform/web_string.h"
#include "third_party/blink/public/platform/web_vector.h"
#include "third_party/blink/public/web/web_text_checking_result.h"

namespace content {

// A spell-checker used for web tests. This class only implements the minimal
// functionalities required by web tests, i.e. this class just compares the
// given string with known misspelled words in web tests and mark them as
// misspelled. Even though this is sufficient for web tests, this class is not
// suitable for any other usages.
class WebTestSpellChecker {
 public:
  static void FillSuggestionList(
      const blink::WebString& word,
      blink::WebVector<blink::WebString>* suggestions);

  WebTestSpellChecker();
  ~WebTestSpellChecker();

  WebTestSpellChecker(const WebTestSpellChecker&) = delete;
  WebTestSpellChecker& operator=(const WebTestSpellChecker&) = delete;

  // Checks the spellings of the specified text.
  // This function returns true if the text consists of valid words, and
  // returns false if it includes invalid words.
  // When the given text includes invalid words, this function sets the
  // position of the first invalid word to misspelledOffset, and the length of
  // the first invalid word to misspelledLength, respectively.
  // For example, when the given text is "   zz zz", this function sets 3 to
  // misspelledOffset and 2 to misspelledLength, respectively.
  bool SpellCheckWord(const blink::WebString& text,
                      size_t* misspelled_offset,
                      size_t* misspelled_length);

  // Checks whether the specified text can be spell checked immediately using
  // the spell checker cache.
  bool HasInCache(const blink::WebString& text);

  // Checks whether the specified text is a misspelling comprised of more
  // than one word. If it is, append multiple results to the results vector.
  bool IsMultiWordMisspelling(
      const blink::WebString& text,
      std::vector<blink::WebTextCheckingResult>* results);

 private:
  // Initialize the internal resources if we need to initialize it.
  // Initializing this object may take long time. To prevent from hurting
  // the performance of test_shell, we initialize this object when
  // SpellCheckWord() is called for the first time.
  // To be compliant with SpellCheck:InitializeIfNeeded(), this function
  // returns true if this object is downloading a dictionary, otherwise
  // it returns false.
  bool InitializeIfNeeded();

  // A table that consists of misspelled words.
  std::vector<std::u16string> misspelled_words_;

  // A flag representing whether or not this object is initialized.
  bool initialized_ = false;
};

}  // namespace content

#endif  // CONTENT_WEB_TEST_RENDERER_WEB_TEST_SPELL_CHECKER_H_
