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 /* -*- 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/. */

 #include "nsTArray.h"

 #include "nsCharSeparatedTokenizer.h"

 #include "nsEscape.h"

 #include "nsIURI.h"

 #include <utility>

 #include "nsMediaFragmentURIParser.h"

 using std::pair;

 using std::make_pair;

 namespace mozilla { namespace net {

 nsMediaFragmentURIParser::nsMediaFragmentURIParser(nsIURI* aURI)

   : mClipUnit(eClipUnit_Pixel)

 {

   nsAutoCString ref;

   aURI->GetRef(ref);

   Parse(ref);

 }

 nsMediaFragmentURIParser::nsMediaFragmentURIParser(nsCString& aRef)

   : mClipUnit(eClipUnit_Pixel)

 {

   Parse(aRef);

 }

 bool nsMediaFragmentURIParser::ParseNPT(nsDependentSubstring aString)

 {

   nsDependentSubstring original(aString);

   if (aString.Length() > 4 &&

       aString[0] == 'n' && aString[1] == 'p' &&

       aString[2] == 't' && aString[3] == ':') {

     aString.Rebind(aString, 4);

   }

   if (aString.Length() == 0) {

     return false;

   }

   double start = -1.0;

   double end = -1.0;

   ParseNPTTime(aString, start);

   if (aString.Length() == 0) {

     mStart.construct(start);

     return true;

   }

   if (aString[0] != ',') {

     aString.Rebind(original, 0);

     return false;

   }

   aString.Rebind(aString, 1);

   if (aString.Length() == 0) {

     aString.Rebind(original, 0);

     return false;

   }

   ParseNPTTime(aString, end);

   if (end <= start || aString.Length() != 0) {

     aString.Rebind(original, 0);

     return false;

   }

   mStart.construct(start);

   mEnd.construct(end);

   return true;

 }

 bool nsMediaFragmentURIParser::ParseNPTTime(nsDependentSubstring& aString, double& aTime)

 {

   if (aString.Length() == 0) {

     return false;

   }

   return

     ParseNPTHHMMSS(aString, aTime) ||

     ParseNPTMMSS(aString, aTime) ||

     ParseNPTSec(aString, aTime);

 }

 // Return true if the given character is a numeric character

 static bool IsDigit(nsDependentSubstring::char_type aChar)

 {

   return (aChar >= '0' && aChar <= '9');

 }

 // Return the index of the first character in the string that is not

 // a numerical digit, starting from 'aStart'.

 static uint32_t FirstNonDigit(nsDependentSubstring& aString, uint32_t aStart)

 {

    while (aStart < aString.Length() && IsDigit(aString[aStart])) {

     ++aStart;

   }

   return aStart;

 }

 bool nsMediaFragmentURIParser::ParseNPTSec(nsDependentSubstring& aString, double& aSec)

 {

   nsDependentSubstring original(aString);

   if (aString.Length() == 0) {

     return false;

   }

   uint32_t index = FirstNonDigit(aString, 0);

   if (index == 0) {

     return false;

   }

   nsDependentSubstring n(aString, 0, index);

   nsresult ec;

   int32_t s = PromiseFlatString(n).ToInteger(&ec);

   if (NS_FAILED(ec)) {

     return false;

   }

   aString.Rebind(aString, index);

   double fraction = 0.0;

   if (!ParseNPTFraction(aString, fraction)) {

     aString.Rebind(original, 0);

     return false;

   }

   aSec = s + fraction;

   return true;

 }

 bool nsMediaFragmentURIParser::ParseNPTMMSS(nsDependentSubstring& aString, double& aTime)

 {

   nsDependentSubstring original(aString);

   uint32_t mm = 0;

   uint32_t ss = 0;

   double fraction = 0.0;

   if (!ParseNPTMM(aString, mm)) {

     aString.Rebind(original, 0);

     return false;

   }

   if (aString.Length() < 2 || aString[0] != ':') {

     aString.Rebind(original, 0);

     return false;

   }

   aString.Rebind(aString, 1);

   if (!ParseNPTSS(aString, ss)) {

     aString.Rebind(original, 0);

     return false;

   }

   if (!ParseNPTFraction(aString, fraction)) {

     aString.Rebind(original, 0);

     return false;

   }

   aTime = mm * 60 + ss + fraction;

   return true;

 }

 bool nsMediaFragmentURIParser::ParseNPTFraction(nsDependentSubstring& aString, double& aFraction)

 {

   double fraction = 0.0;

   if (aString.Length() > 0 && aString[0] == '.') {

     uint32_t index = FirstNonDigit(aString, 1);

     if (index > 1) {

       nsDependentSubstring number(aString, 0, index);

       nsresult ec;

       fraction = PromiseFlatString(number).ToDouble(&ec);

       if (NS_FAILED(ec)) {

         return false;

       }

     }

     aString.Rebind(aString, index);

   }

   aFraction = fraction;

   return true;

 }

 bool nsMediaFragmentURIParser::ParseNPTHHMMSS(nsDependentSubstring& aString, double& aTime)

 {

   nsDependentSubstring original(aString);

   uint32_t hh = 0;

   double seconds = 0.0;

   if (!ParseNPTHH(aString, hh)) {

     return false;

   }

   if (aString.Length() < 2 || aString[0] != ':') {

     aString.Rebind(original, 0);

     return false;

   }

   aString.Rebind(aString, 1);

   if (!ParseNPTMMSS(aString, seconds)) {

     aString.Rebind(original, 0);

     return false;

   }

   aTime = hh * 3600 + seconds;

   return true;

 }

 bool nsMediaFragmentURIParser::ParseNPTHH(nsDependentSubstring& aString, uint32_t& aHour)

 {

   if (aString.Length() == 0) {

     return false;

   }

   uint32_t index = FirstNonDigit(aString, 0);

   if (index == 0) {

     return false;

   }

   nsDependentSubstring n(aString, 0, index);

   nsresult ec;

   int32_t u = PromiseFlatString(n).ToInteger(&ec);

   if (NS_FAILED(ec)) {

     return false;

   }

   aString.Rebind(aString, index);

   aHour = u;

   return true;

 }

 bool nsMediaFragmentURIParser::ParseNPTMM(nsDependentSubstring& aString, uint32_t& aMinute)

 {

   return ParseNPTSS(aString, aMinute);

 }

 bool nsMediaFragmentURIParser::ParseNPTSS(nsDependentSubstring& aString, uint32_t& aSecond)

 {

   if (aString.Length() < 2) {

     return false;

   }

   if (IsDigit(aString[0]) && IsDigit(aString[1])) {

     nsDependentSubstring n(aString, 0, 2);

     nsresult ec;

     int32_t u = PromiseFlatString(n).ToInteger(&ec);

     if (NS_FAILED(ec)) {

       return false;

     }

     aString.Rebind(aString, 2);

     if (u >= 60)

       return false;

     aSecond = u;

     return true;

   }

   return false;

 }

 static bool ParseInteger(nsDependentSubstring& aString,

                          int32_t& aResult)

 {

   uint32_t index = FirstNonDigit(aString, 0);

   if (index == 0) {

     return false;

   }

   nsDependentSubstring n(aString, 0, index);

   nsresult ec;

   int32_t s = PromiseFlatString(n).ToInteger(&ec);

   if (NS_FAILED(ec)) {

     return false;

   }

   aString.Rebind(aString, index);

   aResult = s;

   return true;

 }

 static bool ParseCommaSeparator(nsDependentSubstring& aString)

 {

   if (aString.Length() > 1 && aString[0] == ',') {

     aString.Rebind(aString, 1);

     return true;

   }

   return false;

 }

 bool nsMediaFragmentURIParser::ParseXYWH(nsDependentSubstring aString)

 {

   int32_t x, y, w, h;

   ClipUnit clipUnit;

   // Determine units.

   if (StringBeginsWith(aString, NS_LITERAL_STRING("pixel:"))) {

     clipUnit = eClipUnit_Pixel;

     aString.Rebind(aString, 6);

   } else if (StringBeginsWith(aString, NS_LITERAL_STRING("percent:"))) {

     clipUnit = eClipUnit_Percent;

     aString.Rebind(aString, 8);

   } else {

     clipUnit = eClipUnit_Pixel;

   }

   // Read and validate coordinates.

   if (ParseInteger(aString, x) && x >= 0 &&

       ParseCommaSeparator(aString)       &&

       ParseInteger(aString, y) && y >= 0 &&

       ParseCommaSeparator(aString)       &&

       ParseInteger(aString, w) && w > 0  &&

       ParseCommaSeparator(aString)       &&

       ParseInteger(aString, h) && h > 0  &&

       aString.Length() == 0) {

     // Reject invalid percentage coordinates.

     if (clipUnit == eClipUnit_Percent &&

         (x + w > 100 || y + h > 100)) {

       return false;

     }

     mClip.construct(x, y, w, h);

     mClipUnit = clipUnit;

     return true;

   }

   return false;

 }

 bool nsMediaFragmentURIParser::ParseMozResolution(nsDependentSubstring aString)

 {

   int32_t w, h;

   // Read and validate coordinates.

   if (ParseInteger(aString, w) && w >= 0 &&

       ParseCommaSeparator(aString)       &&

       ParseInteger(aString, h) && h >= 0 &&

       aString.Length() == 0) {

     mResolution.construct(w,h);

     return true;

   }

   return false;

 }

 bool nsMediaFragmentURIParser::ParseMozSampleSize(nsDependentSubstring aString)

 {

   int32_t sampleSize;

   // Read and validate coordinates.

   if (ParseInteger(aString, sampleSize) && sampleSize > 0) {

     mSampleSize.construct(sampleSize);

     return true;

   }

   return false;

 }

 void nsMediaFragmentURIParser::Parse(nsACString& aRef)

 {

   // Create an array of possibly-invalid media fragments.

   nsTArray< std::pair<nsCString, nsCString> > fragments;

   nsCCharSeparatedTokenizer tokenizer(aRef, '&');

   while (tokenizer.hasMoreTokens()) {

     const nsCSubstring& nv = tokenizer.nextToken();

     int32_t index = nv.FindChar('=');

     if (index >= 0) {

       nsAutoCString name;

       nsAutoCString value;

       NS_UnescapeURL(StringHead(nv, index), esc_Ref | esc_AlwaysCopy, name);

       NS_UnescapeURL(Substring(nv, index + 1, nv.Length()),

                      esc_Ref | esc_AlwaysCopy, value);

       fragments.AppendElement(make_pair(name, value));

     }

   }

   // Parse the media fragment values.

   bool gotTemporal = false, gotSpatial = false,

       gotResolution = false, gotSampleSize = false;

   for (int i = fragments.Length() - 1 ; i >= 0 ; --i) {

     if (gotTemporal && gotSpatial && gotResolution && gotSampleSize) {

       // We've got one of each possible type. No need to look at the rest.

       break;

     } else if (!gotTemporal && fragments[i].first.EqualsLiteral("t")) {

       nsAutoString value = NS_ConvertUTF8toUTF16(fragments[i].second);

       gotTemporal = ParseNPT(nsDependentSubstring(value, 0));

     } else if (!gotSpatial && fragments[i].first.EqualsLiteral("xywh")) {

       nsAutoString value = NS_ConvertUTF8toUTF16(fragments[i].second);

       gotSpatial = ParseXYWH(nsDependentSubstring(value, 0));

     } else if (!gotResolution && fragments[i].first.EqualsLiteral("-moz-resolution")) {

       nsAutoString value = NS_ConvertUTF8toUTF16(fragments[i].second);

       gotResolution = ParseMozResolution(nsDependentSubstring(value, 0));

     } else if (!gotSampleSize && fragments[i].first.EqualsLiteral("-moz-samplesize")) {

       nsAutoString value = NS_ConvertUTF8toUTF16(fragments[i].second);

       gotSampleSize = ParseMozSampleSize(nsDependentSubstring(value, 0));

     }

   }

 }

 }} // namespace mozilla::net