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 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */

 /* 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/. */

 // IWYU pragma: private, include "nsString.h"

 #ifndef nsReadableUtils_h___

 #define nsReadableUtils_h___

   /**

    * I guess all the routines in this file are all mis-named.

    * According to our conventions, they should be |NS_xxx|.

    */

 #include "nsAString.h"

 #include "nsTArrayForwardDeclare.h"

 inline size_t Distance( const nsReadingIterator<char16_t>& start, const nsReadingIterator<char16_t>& end )

   {

     return end.get() - start.get();

   }

 inline size_t Distance( const nsReadingIterator<char>& start, const nsReadingIterator<char>& end )

   {

     return end.get() - start.get();

   }

 void LossyCopyUTF16toASCII( const nsAString& aSource, nsACString& aDest );

 void CopyASCIItoUTF16( const nsACString& aSource, nsAString& aDest );

 void LossyCopyUTF16toASCII( const char16_t* aSource, nsACString& aDest );

 void CopyASCIItoUTF16( const char* aSource, nsAString& aDest );

 void CopyUTF16toUTF8( const nsAString& aSource, nsACString& aDest );

 void CopyUTF8toUTF16( const nsACString& aSource, nsAString& aDest );

 void CopyUTF16toUTF8( const char16_t* aSource, nsACString& aDest );

 void CopyUTF8toUTF16( const char* aSource, nsAString& aDest );

 void LossyAppendUTF16toASCII( const nsAString& aSource, nsACString& aDest );

 void AppendASCIItoUTF16( const nsACString& aSource, nsAString& aDest );

 bool AppendASCIItoUTF16( const nsACString& aSource, nsAString& aDest,

                          const mozilla::fallible_t& ) NS_WARN_UNUSED_RESULT;

 void LossyAppendUTF16toASCII( const char16_t* aSource, nsACString& aDest );

 void AppendASCIItoUTF16( const char* aSource, nsAString& aDest );

 void AppendUTF16toUTF8( const nsAString& aSource, nsACString& aDest );

 bool AppendUTF16toUTF8( const nsAString& aSource, nsACString& aDest,

                         const mozilla::fallible_t& ) NS_WARN_UNUSED_RESULT;

 void AppendUTF8toUTF16( const nsACString& aSource, nsAString& aDest );

 bool AppendUTF8toUTF16( const nsACString& aSource, nsAString& aDest,

                         const mozilla::fallible_t& ) NS_WARN_UNUSED_RESULT;

 void AppendUTF16toUTF8( const char16_t* aSource, nsACString& aDest );

 void AppendUTF8toUTF16( const char* aSource, nsAString& aDest );

 #ifdef MOZ_USE_CHAR16_WRAPPER

 inline void AppendUTF16toUTF8( char16ptr_t aSource, nsACString& aDest )

   {

     return AppendUTF16toUTF8(static_cast<const char16_t*>(aSource), aDest);

   }

 #endif

   /**

    * Returns a new |char| buffer containing a zero-terminated copy of |aSource|.

    *

    * Allocates and returns a new |char| buffer which you must free with |nsMemory::Free|.

    * Performs a lossy encoding conversion by chopping 16-bit wide characters down to 8-bits wide while copying |aSource| to your new buffer.

    * This conversion is not well defined; but it reproduces legacy string behavior.

    * The new buffer is zero-terminated, but that may not help you if |aSource| contains embedded nulls.

    *

    * @param aSource a 16-bit wide string

    * @return a new |char| buffer you must free with |nsMemory::Free|.

    */

 char* ToNewCString( const nsAString& aSource );

   /**

    * Returns a new |char| buffer containing a zero-terminated copy of |aSource|.

    *

    * Allocates and returns a new |char| buffer which you must free with |nsMemory::Free|.

    * The new buffer is zero-terminated, but that may not help you if |aSource| contains embedded nulls.

    *

    * @param aSource an 8-bit wide string

    * @return a new |char| buffer you must free with |nsMemory::Free|.

    */

 char* ToNewCString( const nsACString& aSource );

   /**

    * Returns a new |char| buffer containing a zero-terminated copy of |aSource|.

    *

    * Allocates and returns a new |char| buffer which you must free with 

    * |nsMemory::Free|.

    * Performs an encoding conversion from a UTF-16 string to a UTF-8 string

    * copying |aSource| to your new buffer.

    * The new buffer is zero-terminated, but that may not help you if |aSource| 

    * contains embedded nulls.

    *

    * @param aSource a UTF-16 string (made of char16_t's)

    * @param aUTF8Count the number of 8-bit units that was returned

    * @return a new |char| buffer you must free with |nsMemory::Free|.

    */

 char* ToNewUTF8String( const nsAString& aSource, uint32_t *aUTF8Count = nullptr );

   /**

    * Returns a new |char16_t| buffer containing a zero-terminated copy of 

    * |aSource|.

    *

    * Allocates and returns a new |char16_t| buffer which you must free with 

    * |nsMemory::Free|.

    * The new buffer is zero-terminated, but that may not help you if |aSource| 

    * contains embedded nulls.

    *

    * @param aSource a UTF-16 string

    * @return a new |char16_t| buffer you must free with |nsMemory::Free|.

    */

 char16_t* ToNewUnicode( const nsAString& aSource );

   /**

    * Returns a new |char16_t| buffer containing a zero-terminated copy of |aSource|.

    *

    * Allocates and returns a new |char16_t| buffer which you must free with |nsMemory::Free|.

    * Performs an encoding conversion by 0-padding 8-bit wide characters up to 16-bits wide while copying |aSource| to your new buffer.

    * This conversion is not well defined; but it reproduces legacy string behavior.

    * The new buffer is zero-terminated, but that may not help you if |aSource| contains embedded nulls.

    *

    * @param aSource an 8-bit wide string (a C-string, NOT UTF-8)

    * @return a new |char16_t| buffer you must free with |nsMemory::Free|.

    */

 char16_t* ToNewUnicode( const nsACString& aSource );

   /**

    * Returns the required length for a char16_t buffer holding

    * a copy of aSource, using UTF-8 to UTF-16 conversion.

    * The length does NOT include any space for zero-termination.

    *

    * @param aSource an 8-bit wide string, UTF-8 encoded

    * @return length of UTF-16 encoded string copy, not zero-terminated

    */

 uint32_t CalcUTF8ToUnicodeLength( const nsACString& aSource );

   /**

    * Copies the source string into the specified buffer, converting UTF-8 to

    * UTF-16 in the process. The conversion is well defined for valid UTF-8

    * strings.

    * The copied string will be zero-terminated! Any embedded nulls will be

    * copied nonetheless. It is the caller's responsiblity to ensure the buffer

    * is large enough to hold the string copy plus one char16_t for

    * zero-termination!

    *

    * @see CalcUTF8ToUnicodeLength( const nsACString& )

    * @see UTF8ToNewUnicode( const nsACString&, uint32_t* )

    *

    * @param aSource an 8-bit wide string, UTF-8 encoded

    * @param aBuffer the buffer holding the converted string copy

    * @param aUTF16Count receiving optionally the number of 16-bit units that

    *                    were copied

    * @return aBuffer pointer, for convenience 

    */

 char16_t* UTF8ToUnicodeBuffer( const nsACString& aSource,

                                 char16_t *aBuffer,

                                 uint32_t *aUTF16Count = nullptr );

   /**

    * Returns a new |char16_t| buffer containing a zero-terminated copy

    * of |aSource|.

    *

    * Allocates and returns a new |char| buffer which you must free with

    * |nsMemory::Free|.  Performs an encoding conversion from UTF-8 to UTF-16 

    * while copying |aSource| to your new buffer.  This conversion is well defined

    * for a valid UTF-8 string.  The new buffer is zero-terminated, but that 

    * may not help you if |aSource| contains embedded nulls.

    *

    * @param aSource an 8-bit wide string, UTF-8 encoded

    * @param aUTF16Count the number of 16-bit units that was returned

    * @return a new |char16_t| buffer you must free with |nsMemory::Free|.

    *         (UTF-16 encoded)

    */

 char16_t* UTF8ToNewUnicode( const nsACString& aSource, uint32_t *aUTF16Count = nullptr );

   /**

    * Copies |aLength| 16-bit code units from the start of |aSource| to the

    * |char16_t| buffer |aDest|.

    *

    * After this operation |aDest| is not null terminated.

    *

    * @param aSource a UTF-16 string

    * @param aSrcOffset start offset in the source string

    * @param aDest a |char16_t| buffer

    * @param aLength the number of 16-bit code units to copy

    * @return pointer to destination buffer - identical to |aDest|

    */

 char16_t* CopyUnicodeTo( const nsAString& aSource,

                                  uint32_t aSrcOffset,

                                  char16_t* aDest,

                                  uint32_t aLength );

   /**

    * Copies 16-bit characters between iterators |aSrcStart| and

    * |aSrcEnd| to the writable string |aDest|. Similar to the

    * |nsString::Mid| method.

    *

    * After this operation |aDest| is not null terminated.

    *

    * @param aSrcStart start source iterator

    * @param aSrcEnd end source iterator

    * @param aDest destination for the copy

    */

 void CopyUnicodeTo( const nsAString::const_iterator& aSrcStart,

                            const nsAString::const_iterator& aSrcEnd,

                            nsAString& aDest );

   /**

    * Appends 16-bit characters between iterators |aSrcStart| and

    * |aSrcEnd| to the writable string |aDest|. 

    *

    * After this operation |aDest| is not null terminated.

    *

    * @param aSrcStart start source iterator

    * @param aSrcEnd end source iterator

    * @param aDest destination for the copy

    */

 void AppendUnicodeTo( const nsAString::const_iterator& aSrcStart,

                              const nsAString::const_iterator& aSrcEnd,

                              nsAString& aDest );

   /**

    * Returns |true| if |aString| contains only ASCII characters, that is, characters in the range (0x00, 0x7F).

    *

    * @param aString a 16-bit wide string to scan

    */

 bool IsASCII( const nsAString& aString );

   /**

    * Returns |true| if |aString| contains only ASCII characters, that is, characters in the range (0x00, 0x7F).

    *

    * @param aString a 8-bit wide string to scan

    */

 bool IsASCII( const nsACString& aString );

   /**

    * Returns |true| if |aString| is a valid UTF-8 string.

    * XXX This is not bullet-proof and nor an all-purpose UTF-8 validator. 

    * It is mainly written to replace and roughly equivalent to

    *

    *    str.Equals(NS_ConvertUTF16toUTF8(NS_ConvertUTF8toUTF16(str)))

    *

    * (see bug 191541)

    * As such,  it does not check for non-UTF-8 7bit encodings such as 

    * ISO-2022-JP and HZ. 

    *

    * It rejects sequences with the following errors:

    *

    * byte sequences that cannot be decoded into characters according to

    *   UTF-8's rules (including cases where the input is part of a valid

    *   UTF-8 sequence but starts or ends mid-character)

    * overlong sequences (i.e., cases where a character was encoded

    *   non-canonically by using more bytes than necessary)

    * surrogate codepoints (i.e., the codepoints reserved for

        representing astral characters in UTF-16)

    * codepoints above the unicode range (i.e., outside the first 17

    *   planes; higher than U+10FFFF), in accordance with

    *   http://tools.ietf.org/html/rfc3629

    * when aRejectNonChar is true (the default), any codepoint whose low

    *   16 bits are 0xFFFE or 0xFFFF

    *

    * @param aString an 8-bit wide string to scan

    * @param aRejectNonChar a boolean to control the rejection of utf-8

    *        non characters

    */

 bool IsUTF8( const nsACString& aString, bool aRejectNonChar = true );

 bool ParseString(const nsACString& aAstring, char aDelimiter, 

                           nsTArray<nsCString>& aArray);

   /**

    * Converts case in place in the argument string.

    */

 void ToUpperCase( nsACString& );

 void ToLowerCase( nsACString& );

 void ToUpperCase( nsCSubstring& );

 void ToLowerCase( nsCSubstring& );

   /**

    * Converts case from string aSource to aDest.

    */

 void ToUpperCase( const nsACString& aSource, nsACString& aDest );

 void ToLowerCase( const nsACString& aSource, nsACString& aDest );

   /**

    * Finds the leftmost occurrence of |aPattern|, if any in the range |aSearchStart|..|aSearchEnd|.

    *

    * Returns |true| if a match was found, and adjusts |aSearchStart| and |aSearchEnd| to

    * point to the match.  If no match was found, returns |false| and makes |aSearchStart == aSearchEnd|.

    *

    * Currently, this is equivalent to the O(m*n) implementation previously on |ns[C]String|.

    * If we need something faster, then we can implement that later.

    */

 bool FindInReadable( const nsAString& aPattern, nsAString::const_iterator&, nsAString::const_iterator&, const nsStringComparator& = nsDefaultStringComparator() );

 bool FindInReadable( const nsACString& aPattern, nsACString::const_iterator&, nsACString::const_iterator&, const nsCStringComparator& = nsDefaultCStringComparator() );

 /* sometimes we don't care about where the string was, just that we

  * found it or not */

 inline bool FindInReadable( const nsAString& aPattern, const nsAString& aSource, const nsStringComparator& compare = nsDefaultStringComparator() )

 {

   nsAString::const_iterator start, end;

   aSource.BeginReading(start);

   aSource.EndReading(end);

   return FindInReadable(aPattern, start, end, compare);

 }

 inline bool FindInReadable( const nsACString& aPattern, const nsACString& aSource, const nsCStringComparator& compare = nsDefaultCStringComparator() )

 {

   nsACString::const_iterator start, end;

   aSource.BeginReading(start);

   aSource.EndReading(end);

   return FindInReadable(aPattern, start, end, compare);

 }

 bool CaseInsensitiveFindInReadable( const nsACString& aPattern, nsACString::const_iterator&, nsACString::const_iterator& );

   /**

    * Finds the rightmost occurrence of |aPattern| 

    * Returns |true| if a match was found, and adjusts |aSearchStart| and |aSearchEnd| to

    * point to the match.  If no match was found, returns |false| and makes |aSearchStart == aSearchEnd|.

    *

    */

 bool RFindInReadable( const nsAString& aPattern, nsAString::const_iterator&, nsAString::const_iterator&, const nsStringComparator& = nsDefaultStringComparator() );

 bool RFindInReadable( const nsACString& aPattern, nsACString::const_iterator&, nsACString::const_iterator&, const nsCStringComparator& = nsDefaultCStringComparator() );

    /**

    * Finds the leftmost occurrence of |aChar|, if any in the range 

    * |aSearchStart|..|aSearchEnd|.

    *

    * Returns |true| if a match was found, and adjusts |aSearchStart| to

    * point to the match.  If no match was found, returns |false| and 

    * makes |aSearchStart == aSearchEnd|.

    */

 bool FindCharInReadable( char16_t aChar, nsAString::const_iterator& aSearchStart, const nsAString::const_iterator& aSearchEnd );

 bool FindCharInReadable( char aChar, nsACString::const_iterator& aSearchStart, const nsACString::const_iterator& aSearchEnd );

     /**

     * Finds the number of occurences of |aChar| in the string |aStr|

     */

 uint32_t CountCharInReadable( const nsAString& aStr,

                                      char16_t aChar );

 uint32_t CountCharInReadable( const nsACString& aStr,

                                      char aChar );

 bool

 StringBeginsWith( const nsAString& aSource, const nsAString& aSubstring,

                   const nsStringComparator& aComparator =

                                               nsDefaultStringComparator() );

 bool

 StringBeginsWith( const nsACString& aSource, const nsACString& aSubstring,

                   const nsCStringComparator& aComparator =

                                                nsDefaultCStringComparator() );

 bool

 StringEndsWith( const nsAString& aSource, const nsAString& aSubstring,

                 const nsStringComparator& aComparator =

                                             nsDefaultStringComparator() );

 bool

 StringEndsWith( const nsACString& aSource, const nsACString& aSubstring,

                 const nsCStringComparator& aComparator =

                                              nsDefaultCStringComparator() );

 const nsAFlatString& EmptyString();

 const nsAFlatCString& EmptyCString();

 const nsAFlatString& NullString();

 const nsAFlatCString& NullCString();

    /**

    * Compare a UTF-8 string to an UTF-16 string.

    *

    * Returns 0 if the strings are equal, -1 if aUTF8String is less

    * than aUTF16Count, and 1 in the reverse case.  In case of fatal

    * error (eg the strings are not valid UTF8 and UTF16 respectively),

    * this method will return INT32_MIN.

    */

 int32_t

 CompareUTF8toUTF16(const nsASingleFragmentCString& aUTF8String,

                    const nsASingleFragmentString& aUTF16String);

 void

 AppendUCS4ToUTF16(const uint32_t aSource, nsAString& aDest);

 template<class T>

 inline bool EnsureStringLength(T& aStr, uint32_t aLen)

 {

     aStr.SetLength(aLen);

     return (aStr.Length() == aLen);

 }

 #endif // !defined(nsReadableUtils_h___)