1/*
2 * Copyright (C) 2009 Google Inc. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions are
6 * met:
7 *
8 *     * Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 *     * Redistributions in binary form must reproduce the above
11 * copyright notice, this list of conditions and the following disclaimer
12 * in the documentation and/or other materials provided with the
13 * distribution.
14 *     * Neither the name of Google Inc. nor the names of its
15 * contributors may be used to endorse or promote products derived from
16 * this software without specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
21 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
22 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
23 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
24 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
28 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29 */
30
31#include "config.h"
32#include "public/web/WebSearchableFormData.h"
33
34#include "core/HTMLNames.h"
35#include "core/InputTypeNames.h"
36#include "core/dom/Document.h"
37#include "core/html/FormDataList.h"
38#include "core/html/HTMLFormControlElement.h"
39#include "core/html/HTMLFormElement.h"
40#include "core/html/HTMLInputElement.h"
41#include "core/html/HTMLOptionElement.h"
42#include "core/html/HTMLSelectElement.h"
43#include "platform/network/FormDataBuilder.h"
44#include "public/web/WebFormElement.h"
45#include "public/web/WebInputElement.h"
46#include "wtf/text/TextEncoding.h"
47
48namespace blink {
49
50using namespace HTMLNames;
51
52namespace {
53
54// Gets the encoding for the form.
55void GetFormEncoding(const HTMLFormElement* form, WTF::TextEncoding* encoding)
56{
57    String str(form->getAttribute(HTMLNames::accept_charsetAttr));
58    str.replace(',', ' ');
59    Vector<String> charsets;
60    str.split(' ', charsets);
61    for (Vector<String>::const_iterator i(charsets.begin()); i != charsets.end(); ++i) {
62        *encoding = WTF::TextEncoding(*i);
63        if (encoding->isValid())
64            return;
65    }
66    if (!form->document().loader())
67         return;
68    *encoding = WTF::TextEncoding(form->document().encoding());
69}
70
71// Returns true if the submit request results in an HTTP URL.
72bool IsHTTPFormSubmit(const HTMLFormElement* form)
73{
74    // FIXME: This function is insane. This is an overly complicated way to get this information.
75    String action(form->action());
76    // The isNull() check is trying to avoid completeURL returning KURL() when passed a null string.
77    return form->document().completeURL(action.isNull() ? "" : action).protocolIs("http");
78}
79
80// If the form does not have an activated submit button, the first submit
81// button is returned.
82HTMLFormControlElement* GetButtonToActivate(HTMLFormElement* form)
83{
84    HTMLFormControlElement* firstSubmitButton = 0;
85    const FormAssociatedElement::List& element = form->associatedElements();
86    for (FormAssociatedElement::List::const_iterator i(element.begin()); i != element.end(); ++i) {
87        if (!(*i)->isFormControlElement())
88            continue;
89        HTMLFormControlElement* control = toHTMLFormControlElement(*i);
90        if (control->isActivatedSubmit()) {
91            // There's a button that is already activated for submit, return 0.
92            return 0;
93        }
94        if (!firstSubmitButton && control->isSuccessfulSubmitButton())
95            firstSubmitButton = control;
96    }
97    return firstSubmitButton;
98}
99
100// Returns true if the selected state of all the options matches the default
101// selected state.
102bool IsSelectInDefaultState(HTMLSelectElement* select)
103{
104    const WillBeHeapVector<RawPtrWillBeMember<HTMLElement> >& listItems = select->listItems();
105    if (select->multiple() || select->size() > 1) {
106        for (WillBeHeapVector<RawPtrWillBeMember<HTMLElement> >::const_iterator i(listItems.begin()); i != listItems.end(); ++i) {
107            if (!isHTMLOptionElement(*i))
108                continue;
109            HTMLOptionElement* optionElement = toHTMLOptionElement(*i);
110            if (optionElement->selected() != optionElement->hasAttribute(selectedAttr))
111                return false;
112        }
113        return true;
114    }
115
116    // The select is rendered as a combobox (called menulist in WebKit). At
117    // least one item is selected, determine which one.
118    HTMLOptionElement* initialSelected = 0;
119    for (WillBeHeapVector<RawPtrWillBeMember<HTMLElement> >::const_iterator i(listItems.begin()); i != listItems.end(); ++i) {
120        if (!isHTMLOptionElement(*i))
121            continue;
122        HTMLOptionElement* optionElement = toHTMLOptionElement(*i);
123        if (optionElement->hasAttribute(selectedAttr)) {
124            // The page specified the option to select.
125            initialSelected = optionElement;
126            break;
127        }
128        if (!initialSelected)
129            initialSelected = optionElement;
130    }
131    return !initialSelected || initialSelected->selected();
132}
133
134// Returns true if the form element is in its default state, false otherwise.
135// The default state is the state of the form element on initial load of the
136// page, and varies depending upon the form element. For example, a checkbox is
137// in its default state if the checked state matches the state of the checked attribute.
138bool IsInDefaultState(HTMLFormControlElement* formElement)
139{
140    ASSERT(formElement);
141    if (isHTMLInputElement(*formElement)) {
142        const HTMLInputElement& inputElement = toHTMLInputElement(*formElement);
143        if (inputElement.type() == InputTypeNames::checkbox || inputElement.type() == InputTypeNames::radio)
144            return inputElement.checked() == inputElement.hasAttribute(checkedAttr);
145    } else if (isHTMLSelectElement(*formElement)) {
146        return IsSelectInDefaultState(toHTMLSelectElement(formElement));
147    }
148    return true;
149}
150
151// Look for a suitable search text field in a given HTMLFormElement
152// Return nothing if one of those items are found:
153//  - A text area field
154//  - A file upload field
155//  - A Password field
156//  - More than one text field
157HTMLInputElement* findSuitableSearchInputElement(const HTMLFormElement* form)
158{
159    HTMLInputElement* textElement = 0;
160    const FormAssociatedElement::List& element = form->associatedElements();
161    for (FormAssociatedElement::List::const_iterator i(element.begin()); i != element.end(); ++i) {
162        if (!(*i)->isFormControlElement())
163            continue;
164
165        HTMLFormControlElement* control = toHTMLFormControlElement(*i);
166
167        if (control->isDisabledFormControl() || control->name().isNull())
168            continue;
169
170        if (!IsInDefaultState(control) || isHTMLTextAreaElement(*control))
171            return 0;
172
173        if (isHTMLInputElement(*control) && control->willValidate()) {
174            const HTMLInputElement& input = toHTMLInputElement(*control);
175
176            // Return nothing if a file upload field or a password field are found.
177            if (input.type() == InputTypeNames::file || input.type() == InputTypeNames::password)
178                return 0;
179
180            if (input.isTextField()) {
181                if (textElement) {
182                    // The auto-complete bar only knows how to fill in one value.
183                    // This form has multiple fields; don't treat it as searchable.
184                    return 0;
185                }
186                textElement = toHTMLInputElement(control);
187            }
188        }
189    }
190    return textElement;
191}
192
193// Build a search string based on a given HTMLFormElement and HTMLInputElement
194//
195// Search string output example from www.google.com:
196// "hl=en&source=hp&biw=1085&bih=854&q={searchTerms}&btnG=Google+Search&aq=f&aqi=&aql=&oq="
197//
198// Return false if the provided HTMLInputElement is not found in the form
199bool buildSearchString(const HTMLFormElement* form, Vector<char>* encodedString, WTF::TextEncoding* encoding, const HTMLInputElement* textElement)
200{
201    bool isElementFound = false;
202
203    const FormAssociatedElement::List& elements = form->associatedElements();
204    for (FormAssociatedElement::List::const_iterator i(elements.begin()); i != elements.end(); ++i) {
205        if (!(*i)->isFormControlElement())
206            continue;
207
208        HTMLFormControlElement* control = toHTMLFormControlElement(*i);
209
210        if (control->isDisabledFormControl() || control->name().isNull())
211            continue;
212
213        RefPtrWillBeRawPtr<FormDataList> dataList = FormDataList::create(*encoding);
214        if (!control->appendFormData(*dataList, false))
215            continue;
216
217        const WillBeHeapVector<FormDataList::Item>& items = dataList->items();
218
219        for (WillBeHeapVector<FormDataList::Item>::const_iterator j(items.begin()); j != items.end(); ++j) {
220            if (!encodedString->isEmpty())
221                encodedString->append('&');
222            FormDataBuilder::encodeStringAsFormData(*encodedString, j->data());
223            encodedString->append('=');
224            ++j;
225            if (control == textElement) {
226                encodedString->append("{searchTerms}", 13);
227                isElementFound = true;
228            } else
229                FormDataBuilder::encodeStringAsFormData(*encodedString, j->data());
230        }
231    }
232    return isElementFound;
233}
234} // namespace
235
236WebSearchableFormData::WebSearchableFormData(const WebFormElement& form, const WebInputElement& selectedInputElement)
237{
238    RefPtrWillBeRawPtr<HTMLFormElement> formElement = static_cast<PassRefPtrWillBeRawPtr<HTMLFormElement> >(form);
239    HTMLInputElement* inputElement = static_cast<PassRefPtrWillBeRawPtr<HTMLInputElement> >(selectedInputElement).get();
240
241    // Only consider forms that GET data.
242    // Allow HTTPS only when an input element is provided.
243    if (equalIgnoringCase(formElement->getAttribute(methodAttr), "post")
244        || (!IsHTTPFormSubmit(formElement.get()) && !inputElement))
245        return;
246
247    Vector<char> encodedString;
248    WTF::TextEncoding encoding;
249
250    GetFormEncoding(formElement.get(), &encoding);
251    if (!encoding.isValid()) {
252        // Need a valid encoding to encode the form elements.
253        // If the encoding isn't found webkit ends up replacing the params with
254        // empty strings. So, we don't try to do anything here.
255        return;
256    }
257
258    // Look for a suitable search text field in the form when a
259    // selectedInputElement is not provided.
260    if (!inputElement) {
261        inputElement = findSuitableSearchInputElement(formElement.get());
262
263        // Return if no suitable text element has been found.
264        if (!inputElement)
265            return;
266    }
267
268    HTMLFormControlElement* firstSubmitButton = GetButtonToActivate(formElement.get());
269    if (firstSubmitButton) {
270        // The form does not have an active submit button, make the first button
271        // active. We need to do this, otherwise the URL will not contain the
272        // name of the submit button.
273        firstSubmitButton->setActivatedSubmit(true);
274    }
275
276    bool isValidSearchString = buildSearchString(formElement.get(), &encodedString, &encoding, inputElement);
277
278    if (firstSubmitButton)
279        firstSubmitButton->setActivatedSubmit(false);
280
281    // Return if the search string is not valid.
282    if (!isValidSearchString)
283        return;
284
285    String action(formElement->action());
286    KURL url(formElement->document().completeURL(action.isNull() ? "" : action));
287    RefPtr<FormData> formData = FormData::create(encodedString);
288    url.setQuery(formData->flattenToString());
289    m_url = url;
290    m_encoding = String(encoding.name());
291}
292
293} // namespace blink
294