Revert of [TTS] Gather surrounding text on Tap before any UX.

chrome/browser/android/contextualsearch/search_action.cc

-// Copyright 2016 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 "chrome/browser/android/contextualsearch/search_action.h"
-
-#include <set>
-
-#include "base/android/jni_string.h"
-#include "base/bind.h"
-#include "base/memory/weak_ptr.h"
-#include "base/strings/utf_string_conversions.h"
-#include "chrome/browser/android/contextualsearch/contextual_search_context.h"
-#include "content/public/browser/render_frame_host.h"
-#include "content/public/browser/web_contents.h"
-#include "jni/SearchAction_jni.h"
-#include "url/gurl.h"
-
-using base::android::ConvertUTF8ToJavaString;
-using base::android::JavaParamRef;
-using base::android::ScopedJavaGlobalRef;
-using content::WebContents;
-
-namespace {
-// Context length is set to 1.5K characters for historical reasons:
-// This provided the largest context that would fit in a GET request along with
-// our other required parameters."
-const int kSurroundingTextSize = 1536;
-}
-
-SearchAction::SearchAction(JNIEnv* env, jobject obj) {
-  java_object_.Reset(env, obj);
-}
-
-SearchAction::~SearchAction() {
-  // The Java object can be null in tests only, by calling the default
-  // constructor.
-  if (!java_object_.is_null()) {
-    JNIEnv* env = base::android::AttachCurrentThread();
-    Java_SearchAction_clearNativePointer(env, java_object_.obj());
-  }
-}
-
-void SearchAction::Destroy(JNIEnv* env, const JavaParamRef<jobject>& obj) {
-  delete this;
-}
-
-void SearchAction::RequestSurroundingText(
-    JNIEnv* env,
-    const JavaParamRef<jobject>& obj,
-    const JavaParamRef<jobject>& j_web_contents) {
-  WebContents* web_contents = WebContents::FromJavaWebContents(j_web_contents);
-  DCHECK(web_contents);
-
-  GURL url(web_contents->GetURL());
-  std::string encoding(web_contents->GetEncoding());
-  search_context_.reset(new ContextualSearchContext(true, url, encoding));
-
-  content::RenderFrameHost* focused_frame = web_contents->GetFocusedFrame();
-  if (!focused_frame) {
-    OnSurroundingTextResponse(base::string16(), 0, 0);
-  } else {
-    focused_frame->RequestTextSurroundingSelection(
-        base::Bind(&SearchAction::OnSurroundingTextResponse, AsWeakPtr()),
-        kSurroundingTextSize);
-  }
-}
-
-void SearchAction::OnSurroundingTextResponse(
-    const base::string16& surrounding_text,
-    int focus_start,
-    int focus_end) {
-  // Record the context, which can be accessed later on demand.
-  search_context_->surrounding_text = surrounding_text;
-  search_context_->start_offset = focus_start;
-  search_context_->end_offset = focus_end;
-
-  // Notify Java.
-  JNIEnv* env = base::android::AttachCurrentThread();
-  Java_SearchAction_onSurroundingTextReady(env, java_object_.obj());
-}
-
-std::string SearchAction::FindFocusedWord() {
-  DCHECK(search_context_);
-
-  const base::string16& surrounding_text = search_context_->surrounding_text;
-  int focus_start = search_context_->start_offset;
-  int focus_end = search_context_->end_offset;
-  int surrounding_text_length = surrounding_text.length();
-
-  // First, we need to find the focused word boundaries.
-  int focused_word_start = focus_start;
-  int focused_word_end = focus_end;
-
-  if (surrounding_text_length > 0 &&
-      IsValidCharacter(surrounding_text[focused_word_start])) {
-    // Find focused word start (inclusive)
-    for (int i = focus_start; i >= 0; i--) {
-      focused_word_start = i;
-
-      wchar_t character;
-      if (i > 0) {
-        character = surrounding_text[i - 1];
-
-        if (!IsValidCharacter(character))
-          break;
-      }
-    }
-
-    // Find focused word end (non inclusive)
-    for (int i = focus_end; i < surrounding_text_length; i++) {
-      wchar_t character = surrounding_text[i];
-
-      if (IsValidCharacter(character)) {
-        focused_word_end = i + 1;
-      } else {
-        focused_word_end = i;
-        break;
-      }
-    }
-  }
-
-  return base::UTF16ToUTF8(surrounding_text.substr(
-      focused_word_start, focused_word_end - focused_word_start));
-}
-
-std::string SearchAction::GetSampleText(int sample_length) {
-  DCHECK(search_context_);
-
-  const base::string16& surrounding_text = search_context_->surrounding_text;
-  int focus_start = search_context_->start_offset;
-  int focus_end = search_context_->end_offset;
-  int surrounding_text_length = surrounding_text.length();
-
-  //---------------------------------------------------------------------------
-  // Cut the surrounding size so it can be sent to the Java side.
-
-  // Start equally distributing the size around the focal point.
-  int focal_point_size = focus_end - focus_start;
-  int sample_margin = (sample_length - focal_point_size) / 2;
-  int sample_start = focus_start - sample_margin;
-  int sample_end = focus_end + sample_margin;
-
-  // If the the start is out of bounds, compensate the end side.
-  if (sample_start < 0) {
-    sample_end -= sample_start;
-    sample_start = 0;
-  }
-
-  // If the the end is out of bounds, compensate the start side.
-  if (sample_end > surrounding_text_length) {
-    int diff = sample_end - surrounding_text_length;
-    sample_end = surrounding_text_length;
-    sample_start -= diff;
-  }
-
-  // Trim the start and end to make sure they are within bounds.
-  sample_start = std::max(0, sample_start);
-  sample_end = std::min(surrounding_text_length, sample_end);
-  return base::UTF16ToUTF8(
-      surrounding_text.substr(sample_start, sample_end - sample_start));
-}
-
-bool SearchAction::IsValidCharacter(int char_code) {
-  // See http://www.unicode.org/Public/UCD/latest/ucd/NamesList.txt
-  // See http://jrgraphix.net/research/unicode_blocks.php
-
-  // TODO(donnd): should not include CJK characters!
-  // TODO(donnd): consider using regular expressions.
-
-  if ((char_code >= 11264 && char_code <= 55295) ||  // Asian language symbols
-      (char_code >= 192 && char_code <= 8191) ||  // Letters in many languages
-      (char_code >= 97 && char_code <= 122) ||    // Lowercase letters
-      (char_code >= 65 && char_code <= 90) ||     // Uppercase letters
-      (char_code >= 48 && char_code <= 57)) {     // Numbers
-    return true;
-  }
-
-  return false;
-}
-
-// Testing
-
-SearchAction::SearchAction() {}
-
-void SearchAction::SetContext(std::string surrounding_text,
-                              int focus_start,
-                              int focus_end) {
-  search_context_.reset(new ContextualSearchContext(false, GURL(), ""));
-  search_context_->surrounding_text = base::UTF8ToUTF16(surrounding_text);
-  search_context_->start_offset = focus_start;
-  search_context_->end_offset = focus_end;
-}
-
-// Boilerplate
-
-bool RegisterSearchAction(JNIEnv* env) {
-  return RegisterNativesImpl(env);
-}
-
-jlong Init(JNIEnv* env, const JavaParamRef<jobject>& obj) {
-  SearchAction* content = new SearchAction(env, obj);
-  return reinterpret_cast<intptr_t>(content);
-}