gecko-dev/netwerk/base/nsMediaFragmentURIParser.h

113 строки
4.2 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim:set ts=2 sw=2 sts=2 et cindent: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#if !defined(nsMediaFragmentURIParser_h__)
#define nsMediaFragmentURIParser_h__
#include "mozilla/Maybe.h"
#include "nsStringFwd.h"
#include "nsRect.h"
class nsIURI;
// Class to handle parsing of a W3C media fragment URI as per
// spec at: http://www.w3.org/TR/media-frags/
// Only the temporaral URI portion of the spec is implemented.
// To use:
// a) Construct an instance with the URI containing the fragment
// b) Check for the validity of the values you are interested in
// using e.g. HasStartTime().
// c) If the values are valid, obtain them using e.g. GetStartTime().
namespace mozilla { namespace net {
enum ClipUnit
{
eClipUnit_Pixel,
eClipUnit_Percent,
};
class nsMediaFragmentURIParser
{
public:
// Create a parser with the provided URI.
explicit nsMediaFragmentURIParser(nsIURI* aURI);
// Create a parser with the provided URI reference portion.
explicit nsMediaFragmentURIParser(nsCString& aRef);
// True if a valid temporal media fragment indicated a start time.
bool HasStartTime() const { return mStart.isSome(); }
// If a valid temporal media fragment indicated a start time, returns
// it in units of seconds. If not, defaults to 0.
double GetStartTime() const { return *mStart; }
// True if a valid temporal media fragment indicated an end time.
bool HasEndTime() const { return mEnd.isSome(); }
// If a valid temporal media fragment indicated an end time, returns
// it in units of seconds. If not, defaults to -1.
double GetEndTime() const { return *mEnd; }
// True if a valid spatial media fragment indicated a clipping region.
bool HasClip() const { return mClip.isSome(); }
// True if a valid spatial media fragment indicated a resolution.
bool HasResolution() const { return mResolution.isSome(); }
// True if a valid spatial media fragment indicated a resolution.
nsIntSize GetResolution() const { return *mResolution; }
// If a valid spatial media fragment indicated a clipping region,
// returns the region. If not, returns an empty region. The unit
// used depends on the value returned by GetClipUnit().
nsIntRect GetClip() const { return *mClip; }
// If a valid spatial media fragment indicated a clipping region,
// returns the unit used.
ClipUnit GetClipUnit() const { return mClipUnit; }
bool HasSampleSize() const { return mSampleSize.isSome(); }
int GetSampleSize() const { return *mSampleSize; }
private:
// Parse the URI ref provided, looking for media fragments. This is
// the top-level parser the invokes the others below.
void Parse(nsACString& aRef);
// The following methods parse the fragment as per the media
// fragments specification. 'aString' contains the remaining
// fragment data to be parsed. The method returns true
// if the parse was successful and leaves the remaining unparsed
// data in 'aString'. If the parse fails then false is returned
// and 'aString' is left as it was when called.
bool ParseNPT(nsDependentSubstring aString);
bool ParseNPTTime(nsDependentSubstring& aString, double& aTime);
bool ParseNPTSec(nsDependentSubstring& aString, double& aSec);
bool ParseNPTFraction(nsDependentSubstring& aString, double& aFraction);
bool ParseNPTMMSS(nsDependentSubstring& aString, double& aTime);
bool ParseNPTHHMMSS(nsDependentSubstring& aString, double& aTime);
bool ParseNPTHH(nsDependentSubstring& aString, uint32_t& aHour);
bool ParseNPTMM(nsDependentSubstring& aString, uint32_t& aMinute);
bool ParseNPTSS(nsDependentSubstring& aString, uint32_t& aSecond);
bool ParseXYWH(nsDependentSubstring aString);
bool ParseMozResolution(nsDependentSubstring aString);
bool ParseMozSampleSize(nsDependentSubstring aString);
// Media fragment information.
Maybe<double> mStart;
Maybe<double> mEnd;
Maybe<nsIntRect> mClip;
ClipUnit mClipUnit;
Maybe<nsIntSize> mResolution;
Maybe<int> mSampleSize;
};
}} // namespace mozilla::net
#endif