1/*
2 * Copyright (C) 2006, 2007, 2008, 2009, 2010 Apple Inc. All rights reserved.
3 *
4 * This library is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Library General Public
6 * License as published by the Free Software Foundation; either
7 * version 2 of the License, or (at your option) any later version.
8 *
9 * This library is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
12 * Library General Public License for more details.
13 *
14 * You should have received a copy of the GNU Library General Public License
15 * along with this library; see the file COPYING.LIB.  If not, write to
16 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
17 * Boston, MA 02110-1301, USA.
18 *
19 */
20
21#include "config.h"
22#include "StepRange.h"
23
24#include "HTMLInputElement.h"
25#include "HTMLNames.h"
26#include "HTMLParserIdioms.h"
27#include <wtf/MathExtras.h>
28#include <wtf/text/WTFString.h>
29
30using namespace std;
31
32namespace WebCore {
33
34using namespace HTMLNames;
35
36StepRange::StepRange(const HTMLInputElement* element)
37{
38    if (element->hasAttribute(precisionAttr)) {
39        step = 1.0;
40        hasStep = !equalIgnoringCase(element->getAttribute(precisionAttr), "float");
41    } else
42        hasStep = element->getAllowedValueStep(&step);
43
44    maximum = element->maximum();
45    minimum = element->minimum();
46}
47
48double StepRange::clampValue(double value)
49{
50    double clampedValue = max(minimum, min(value, maximum));
51    if (!hasStep)
52        return clampedValue;
53    // Rounds clampedValue to minimum + N * step.
54    clampedValue = minimum + round((clampedValue - minimum) / step) * step;
55    if (clampedValue > maximum)
56       clampedValue -= step;
57    ASSERT(clampedValue >= minimum);
58    ASSERT(clampedValue <= maximum);
59    return clampedValue;
60}
61
62double StepRange::clampValue(const String& stringValue)
63{
64    double value;
65    bool parseSuccess = parseToDoubleForNumberType(stringValue, &value);
66    if (!parseSuccess)
67        value = (minimum + maximum) / 2;
68    return clampValue(value);
69}
70
71double StepRange::valueFromElement(HTMLInputElement* element, bool* wasClamped)
72{
73    double oldValue;
74    bool parseSuccess = parseToDoubleForNumberType(element->value(), &oldValue);
75    if (!parseSuccess)
76        oldValue = (minimum + maximum) / 2;
77    double newValue = clampValue(oldValue);
78
79    if (wasClamped)
80        *wasClamped = !parseSuccess || newValue != oldValue;
81
82    return newValue;
83}
84
85}
86