1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
|
// Copyright (c) 2010 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/renderer/translate_helper.h"
#include "base/compiler_specific.h"
#include "chrome/renderer/render_view.h"
#include "third_party/WebKit/WebKit/chromium/public/WebFrame.h"
#include "third_party/WebKit/WebKit/chromium/public/WebScriptSource.h"
using WebKit::WebFrame;
using WebKit::WebScriptSource;
// The delay in millliseconds that we'll wait before checking to see if the
// translate library injected in the page is ready.
static const int kTranslateInitCheckDelayMs = 150;
// The maximum number of times we'll check to see if the translate library
// injected in the page is ready.
static const int kMaxTranslateInitCheckAttempts = 5;
// The delay we wait in milliseconds before checking whether the translation has
// finished.
static const int kTranslateStatusCheckDelayMs = 400;
////////////////////////////////////////////////////////////////////////////////
// TranslateHelper, public:
//
TranslateHelper::TranslateHelper(RenderView* render_view)
: render_view_(render_view),
ALLOW_THIS_IN_INITIALIZER_LIST(method_factory_(this)) {
}
void TranslateHelper::TranslatePage(int page_id,
const std::string& source_lang,
const std::string& target_lang,
const std::string& translate_script) {
if (render_view_->page_id() != page_id)
return; // We navigated away, nothing to do.
if (!IsTranslateLibAvailable()) {
// Evaluate the script to add the translation related method to the global
// context of the page.
ExecuteScript(translate_script);
DCHECK(IsTranslateLibAvailable());
}
// Cancel any pending tasks related to a previous translation, they are now
// obsolete.
method_factory_.RevokeAll();
TranslatePageImpl(page_id, source_lang, target_lang, 0);
}
void TranslateHelper::RevertTranslation(int page_id) {
if (render_view_->page_id() != page_id)
return; // We navigated away, nothing to do.
if (!IsTranslateLibAvailable()) {
NOTREACHED();
return;
}
WebFrame* main_frame = render_view_->webview()->mainFrame();
if (!main_frame)
return;
main_frame->executeScript(
WebScriptSource(ASCIIToUTF16("cr.googleTranslate.revert()")));
}
////////////////////////////////////////////////////////////////////////////////
// TranslateHelper, protected:
//
bool TranslateHelper::IsTranslateLibAvailable() {
bool lib_available = false;
if (!ExecuteScriptAndGetBoolResult(
"typeof cr != 'undefined' && typeof cr.googleTranslate != 'undefined' && "
"typeof cr.googleTranslate.translate == 'function'", &lib_available)) {
NOTREACHED();
return false;
}
return lib_available;
}
bool TranslateHelper::IsTranslateLibReady() {
bool lib_ready = false;
if (!ExecuteScriptAndGetBoolResult("cr.googleTranslate.libReady",
&lib_ready)) {
NOTREACHED();
return false;
}
return lib_ready;
}
bool TranslateHelper::HasTranslationFinished() {
bool translation_finished = false;
if (!ExecuteScriptAndGetBoolResult("cr.googleTranslate.finished",
&translation_finished)) {
NOTREACHED() << "crGoogleTranslateGetFinished returned unexpected value.";
return true;
}
return translation_finished;
}
bool TranslateHelper::HasTranslationFailed() {
bool translation_failed = false;
if (!ExecuteScriptAndGetBoolResult("cr.googleTranslate.error",
&translation_failed)) {
NOTREACHED() << "crGoogleTranslateGetError returned unexpected value.";
return true;
}
return translation_failed;
}
bool TranslateHelper::StartTranslation(const std::string& source_lang,
const std::string& target_lang) {
bool translate_success = false;
if (!ExecuteScriptAndGetBoolResult("cr.googleTranslate.translate('" +
source_lang + "','" + target_lang + "')",
&translate_success)) {
NOTREACHED();
return false;
}
return translate_success;
}
////////////////////////////////////////////////////////////////////////////////
// TranslateHelper, private:
//
void TranslateHelper::CheckTranslateStatus(int page_id,
const std::string& source_lang,
const std::string& target_lang) {
if (page_id != render_view_->page_id())
return; // This is not the same page, the translation has been canceled.
// First check if there was an error.
if (HasTranslationFailed()) {
NotifyBrowserTranslationFailed(source_lang, target_lang,
TranslateErrors::TRANSLATION_ERROR);
return; // There was an error.
}
if (HasTranslationFinished()) {
// Translation was successfull, notify the browser.
render_view_->Send(new ViewHostMsg_PageTranslated(
render_view_->routing_id(), render_view_->page_id(),
source_lang, target_lang, TranslateErrors::NONE));
return;
}
// The translation is still pending, check again later.
MessageLoop::current()->PostDelayedTask(FROM_HERE,
method_factory_.NewRunnableMethod(&TranslateHelper::CheckTranslateStatus,
page_id, source_lang, target_lang),
DontDelayTasks() ? 0 : kTranslateStatusCheckDelayMs);
}
bool TranslateHelper::ExecuteScript(const std::string& script) {
WebFrame* main_frame = render_view_->webview()->mainFrame();
if (!main_frame)
return false;
main_frame->executeScript(WebScriptSource(ASCIIToUTF16(script)));
return true;
}
bool TranslateHelper::ExecuteScriptAndGetBoolResult(const std::string& script,
bool* value) {
DCHECK(value);
WebFrame* main_frame = render_view_->webview()->mainFrame();
if (!main_frame)
return false;
v8::Handle<v8::Value> v = main_frame->executeScriptAndReturnValue(
WebScriptSource(ASCIIToUTF16(script)));
if (v.IsEmpty() || !v->IsBoolean())
return false;
*value = v->BooleanValue();
return true;
}
void TranslateHelper::TranslatePageImpl(int page_id,
const std::string& source_lang,
const std::string& target_lang,
int count) {
DCHECK_LT(count, kMaxTranslateInitCheckAttempts);
if (page_id != render_view_->page_id())
return;
if (!IsTranslateLibReady()) {
// The library is not ready, try again later, unless we have tried several
// times unsucessfully already.
if (++count >= kMaxTranslateInitCheckAttempts) {
NotifyBrowserTranslationFailed(source_lang, target_lang,
TranslateErrors::INITIALIZATION_ERROR);
return;
}
MessageLoop::current()->PostDelayedTask(FROM_HERE,
method_factory_.NewRunnableMethod(&TranslateHelper::TranslatePageImpl,
page_id, source_lang, target_lang,
count),
DontDelayTasks() ? 0 : count * kTranslateInitCheckDelayMs);
return;
}
if (!StartTranslation(source_lang, target_lang)) {
NotifyBrowserTranslationFailed(source_lang, target_lang,
TranslateErrors::TRANSLATION_ERROR);
return;
}
// Check the status of the translation.
MessageLoop::current()->PostDelayedTask(FROM_HERE,
method_factory_.NewRunnableMethod(&TranslateHelper::CheckTranslateStatus,
page_id, source_lang, target_lang),
DontDelayTasks() ? 0 : kTranslateStatusCheckDelayMs);
}
void TranslateHelper::NotifyBrowserTranslationFailed(
const std::string& source_lang,
const std::string& target_lang,
TranslateErrors::Type error) {
// Notify the browser there was an error.
render_view_->Send(new ViewHostMsg_PageTranslated(
render_view_->routing_id(), render_view_->page_id(),
source_lang, target_lang, error));
}
|
