dom/html/TimeRanges.h

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #ifndef mozilla_dom_TimeRanges_h_
   8 #define mozilla_dom_TimeRanges_h_
   9
  10 #include "nsCOMPtr.h"
  11 #include "nsISupports.h"
  12 #include "nsTArray.h"
  13 #include "nsWrapperCache.h"
  14 #include "mozilla/ErrorResult.h"
  15 #include "TimeUnits.h"
  16
  17 namespace mozilla {
  18
  19 namespace dom {
  20 class TimeRanges;
  21 } // namespace dom
  22
  23 namespace dom {
  24
  25 // Implements media TimeRanges:
  26 // http://www.whatwg.org/specs/web-apps/current-work/multipage/video.html#timeranges
  27 class TimeRanges final : public nsISupports,
  28                          public nsWrapperCache
  29 {
  30 public:
  31   NS_DECL_CYCLE_COLLECTING_ISUPPORTS
  32   NS_DECL_CYCLE_COLLECTION_SCRIPT_HOLDER_CLASS(TimeRanges)
  33
  34   TimeRanges();
  35   explicit TimeRanges(nsISupports* aParent);
  36   explicit TimeRanges(const media::TimeIntervals& aTimeIntervals);
  37   TimeRanges(nsISupports* aParent, const media::TimeIntervals& aTimeIntervals);
  38
  39   media::TimeIntervals ToTimeIntervals() const;
  40
  41   void Add(double aStart, double aEnd);
  42
  43   // Returns the start time of the first range, or -1 if no ranges exist.
  44   double GetStartTime();
  45
  46   // Returns the end time of the last range, or -1 if no ranges exist.
  47   double GetEndTime();
  48
  49   // See http://www.whatwg.org/html/#normalized-timeranges-object
  50   void Normalize(double aTolerance = 0.0);
  51
  52   // Mutate this TimeRange to be the union of this and aOtherRanges.
  53   void Union(const TimeRanges* aOtherRanges, double aTolerance);
  54
  55   // Mutate this TimeRange to be the intersection of this and aOtherRanges.
  56   void Intersection(const TimeRanges* aOtherRanges);
  57
  58   JSObject* WrapObject(JSContext* aCx,
  59                        JS::Handle<JSObject*> aGivenProto) override;
  60
  61   nsISupports* GetParentObject() const;
  62
  63   uint32_t Length() const
  64   {
  65     return mRanges.Length();
  66   }
  67
  68   double Start(uint32_t aIndex, ErrorResult& aRv) const;
  69
  70   double End(uint32_t aIndex, ErrorResult& aRv) const;
  71
  72   double Start(uint32_t aIndex) const
  73   {
  74     return mRanges[aIndex].mStart;
  75   }
  76
  77   double End(uint32_t aIndex) const
  78   {
  79     return mRanges[aIndex].mEnd;
  80   }
  81
  82   // Shift all values by aOffset seconds.
  83   void Shift(double aOffset);
  84
  85 private:
  86   ~TimeRanges();
  87
  88   // Comparator which orders TimeRanges by start time. Used by Normalize().
  89   struct TimeRange
  90   {
  91     TimeRange(double aStart, double aEnd)
  92       : mStart(aStart),
  93         mEnd(aEnd) {}
  94     double mStart;
  95     double mEnd;
  96   };
  97
  98   struct CompareTimeRanges
  99   {
 100     bool Equals(const TimeRange& aTr1, const TimeRange& aTr2) const {
 101       return aTr1.mStart == aTr2.mStart && aTr1.mEnd == aTr2.mEnd;
 102     }
 103
 104     bool LessThan(const TimeRange& aTr1, const TimeRange& aTr2) const {
 105       return aTr1.mStart < aTr2.mStart;
 106     }
 107   };
 108
 109   AutoTArray<TimeRange,4> mRanges;
 110
 111   nsCOMPtr<nsISupports> mParent;
 112
 113 public:
 114   typedef nsTArray<TimeRange>::index_type index_type;
 115   static const index_type NoIndex = index_type(-1);
 116
 117   index_type Find(double aTime, double aTolerance = 0);
 118
 119   bool Contains(double aStart, double aEnd) {
 120     index_type target = Find(aStart);
 121     if (target == NoIndex) {
 122       return false;
 123     }
 124
 125     return mRanges[target].mEnd >= aEnd;
 126   }
 127 };
 128
 129 } // namespace dom
 130 } // namespace mozilla
 131
 132 #endif // mozilla_dom_TimeRanges_h_