1 /*
2 * Copyright (C) 2007, 2009, 2010 Apple 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
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE COMPUTER, INC. OR
17 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
18 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
20 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
21 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
23 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26 #include "config.h"
27
28 #include "TimeRanges.h"
29
30 #include <math.h>
31
32 using namespace WebCore;
33
TimeRanges(float start,float end)34 TimeRanges::TimeRanges(float start, float end)
35 {
36 add(start, end);
37 }
38
copy()39 PassRefPtr<TimeRanges> TimeRanges::copy()
40 {
41 RefPtr<TimeRanges> newSession = TimeRanges::create();
42
43 unsigned size = m_ranges.size();
44 for (unsigned i = 0; i < size; i++)
45 newSession->add(m_ranges[i].m_start, m_ranges[i].m_end);
46
47 return newSession.release();
48 }
49
start(unsigned index,ExceptionCode & ec) const50 float TimeRanges::start(unsigned index, ExceptionCode& ec) const
51 {
52 if (index >= length()) {
53 ec = INDEX_SIZE_ERR;
54 return 0;
55 }
56 return m_ranges[index].m_start;
57 }
58
end(unsigned index,ExceptionCode & ec) const59 float TimeRanges::end(unsigned index, ExceptionCode& ec) const
60 {
61 if (index >= length()) {
62 ec = INDEX_SIZE_ERR;
63 return 0;
64 }
65 return m_ranges[index].m_end;
66 }
67
add(float start,float end)68 void TimeRanges::add(float start, float end)
69 {
70 ASSERT(start <= end);
71 unsigned int overlappingArcIndex;
72 Range addedRange(start, end);
73
74 // For each present range check if we need to:
75 // - merge with the added range, in case we are overlapping or contiguous
76 // - Need to insert in place, we we are completely, not overlapping and not contiguous
77 // in between two ranges.
78 //
79 // TODO: Given that we assume that ranges are correctly ordered, this could be optimized.
80
81 for (overlappingArcIndex = 0; overlappingArcIndex < m_ranges.size(); overlappingArcIndex++) {
82 if (addedRange.isOverlappingRange(m_ranges[overlappingArcIndex])
83 || addedRange.isContiguousWithRange(m_ranges[overlappingArcIndex])) {
84 // We need to merge the addedRange and that range.
85 addedRange = addedRange.unionWithOverlappingOrContiguousRange(m_ranges[overlappingArcIndex]);
86 m_ranges.remove(overlappingArcIndex);
87 overlappingArcIndex--;
88 } else {
89 // Check the case for which there is no more to do
90 if (!overlappingArcIndex) {
91 if (addedRange.isBeforeRange(m_ranges[0])) {
92 // First index, and we are completely before that range (and not contiguous, nor overlapping).
93 // We just need to be inserted here.
94 break;
95 }
96 } else {
97 if (m_ranges[overlappingArcIndex - 1].isBeforeRange(addedRange)
98 && addedRange.isBeforeRange(m_ranges[overlappingArcIndex])) {
99 // We are exactly after the current previous range, and before the current range, while
100 // not overlapping with none of them. Insert here.
101 break;
102 }
103 }
104 }
105 }
106
107 // Now that we are sure we don't overlap with any range, just add it.
108 m_ranges.insert(overlappingArcIndex, addedRange);
109 }
110
contain(float time) const111 bool TimeRanges::contain(float time) const
112 {
113 ExceptionCode unused;
114 for (unsigned n = 0; n < length(); n++) {
115 if (time >= start(n, unused) && time <= end(n, unused))
116 return true;
117 }
118 return false;
119 }
120
nearest(float time) const121 float TimeRanges::nearest(float time) const
122 {
123 ExceptionCode unused;
124 float closest = 0;
125 unsigned count = length();
126 for (unsigned ndx = 0; ndx < count; ndx++) {
127 float startTime = start(ndx, unused);
128 float endTime = end(ndx, unused);
129 if (time >= startTime && time <= endTime)
130 return time;
131 if (fabs(startTime - time) < closest)
132 closest = fabsf(startTime - time);
133 else if (fabs(endTime - time) < closest)
134 closest = fabsf(endTime - time);
135 }
136 return closest;
137 }
138