Introduction to ACF (Another C++ Framework)

//---------------------------------------------------------------------
//
// Copyright (C) 2004 Yingle Jia
//
// Permission to copy, use, modify, sell and distribute this software is 
// granted provided this copyright notice appears in all copies. 
// This software is provided "as is" without express or implied warranty, 
// and with no claim as to its suitability for any purpose.
//

#include "stdafx.h"

namespace Acf {
    namespace IO {

// Constructors

StreamWriter::StreamWriter(String* path, bool append, Acf::Text::Encoding* encoding, 
                           int bufferSize)
{
    if (path == null || encoding == null)
        throw ArgumentNullException();
    if (bufferSize <= 0)
        throw ArgumentOutOfRangeException();

    FileMode mode = append ? FileMode::Append : FileMode::Create;
    FileStreamPtr stream = new FileStream(path, mode, FileAccess::Write, FileShare::Read, 
        DefaultFileStreamBufferSize);

    new(this) StreamWriter(stream, encoding, bufferSize);
}

StreamWriter::StreamWriter(const wchar_t* path, bool append, Acf::Text::Encoding* encoding, 
                           int bufferSize)
{
    if (path == null || encoding == null)
        throw ArgumentNullException();
    if (bufferSize <= 0)
        throw ArgumentOutOfRangeException();

    FileMode mode = append ? FileMode::Append : FileMode::Create;
    FileStreamPtr stream = new FileStream(path, mode, FileAccess::Write, FileShare::Read, 
        DefaultFileStreamBufferSize);

    new(this) StreamWriter(stream, encoding, bufferSize);
}

StreamWriter::StreamWriter(Stream* stream, Acf::Text::Encoding* encoding, int bufferSize)
{
    if (stream == null || encoding == null)
        throw ArgumentNullException();
    if (bufferSize <= 0)
        throw ArgumentOutOfRangeException();

    if (bufferSize < MinBufferSize)
        bufferSize = MinBufferSize;

    this->_stream = stream;
    this->_encoding = encoding;
    this->_encoder = encoding->GetEncoder();

    this->_charBuffer = new Array<wchar_t>(bufferSize);
    this->_byteBuffer = new Array<byte>(encoding->GetMaxByteCount(bufferSize));

    // If we're appending to a Stream that already has data, don't write
    // the preamble junk.
    if (stream->CanSeek && stream->Position > 0)
        this->_haveWrittenPreamble = true;

    this->_closable = true;
}

// Destructor

/*virtual*/ StreamWriter::~StreamWriter()
{
    Close();
}

// Properties

/*virtual*/ StreamPtr StreamWriter::get_BaseStream()
{
    return this->_stream;
}

/*override*/ EncodingPtr StreamWriter::get_Encoding()
{
    return this->_encoding;
}

/*virtual*/ bool StreamWriter::get_AutoFlush()
{
    return this->_autoFlush;
}

/*virtual*/ void StreamWriter::set_AutoFlush(bool value)
{
    this->_autoFlush = value;
    if (value)
        Flush(true, false);
}

// Methods

/*override*/ void StreamWriter::Write(wchar_t value)
{
    if (this->_charPos == this->_charBuffer->Length)
        Flush(false, false);

    this->_charBuffer->Item[this->_charPos++] = value;

    if (this->_autoFlush)
        Flush(true, false);
}

/*override*/ void StreamWriter::Write(Array<wchar_t>* buffer)
{
    if (buffer == null)
        throw ArgumentNullException();

    Write(buffer, 0, buffer->Length);
}

/*override*/ void StreamWriter::Write(Array<wchar_t>* buffer, int index, int count)
{
    Acf::VerifyArrayRange(buffer, index, count);

    while (count > 0)
    {
        if (this->_charPos == this->_charBuffer->Length)
            Flush(false, false);

        int n = this->_charBuffer->Length - this->_charPos;
        if (n > count)
            n = count;

        Array<wchar_t>::Copy(buffer, index, this->_charBuffer, this->_charPos, n);

        this->_charPos += n;
        index += n;
        count -= n;
    }

    if (this->_autoFlush)
        Flush(true, false);
}

/*override*/ void StreamWriter::Write(String* value)
{
    if (value != null)
    {
        int count = value->Length;
        int index = 0;

        while (count > 0)
        {
            if (this->_charPos == this->_charBuffer->Length)
                Flush(false, false);

            int n = this->_charBuffer->Length - this->_charPos;
            if (n > count)
                n = count;

            value->CopyTo(index, this->_charBuffer, this->_charPos, n);

            this->_charPos += n;
            index += n;
            count -= n;
        }

        if (this->_autoFlush)
            Flush(true, false);
    }
}

/*override*/ void StreamWriter::Write(const wchar_t* value)
{
    if (value != null)
    {
        int count = (int) wcslen(value);
        int index = 0;

        while (count > 0)
        {
            if (this->_charPos == this->_charBuffer->Length)
                Flush(false, false);

            int n = this->_charBuffer->Length - this->_charPos;
            if (n > count)
                n = count;

            memcpy(this->_charBuffer->GetItemAddress(this->_charPos), 
                value + index, n * sizeof(wchar_t));

            this->_charPos += n;
            index += n;
            count -= n;
        }

        if (this->_autoFlush)
            Flush(true, false);
    }
}

/*override*/ void StreamWriter::Flush()
{
    Flush(true, true);
}

/*override*/ void StreamWriter::Close()
{
    if (this->_stream != null)
    {
        Flush();

        if (this->_closable)
            this->_stream->Close();
    }

    if (this->_closable && this->_stream != null)
    {
        this->_stream = null;
        this->_byteBuffer = null;
        this->_charBuffer = null;
        this->_encoding = null;
        this->_encoder = null;
    }
}

void StreamWriter::Flush(bool flushStream, bool flushEncoder)
{
    if (this->_stream == null)
        throw InvalidOperationException();

    if (this->_charPos == 0 && !flushStream && !flushEncoder)
        return;

    if (!this->_haveWrittenPreamble)
    {
        RefPtr< Array<byte> > preamble = this->_encoding->GetPreamble();
        if (preamble->Length > 0)
            this->_stream->Write(preamble, 0, preamble->Length);

        this->_haveWrittenPreamble = true;
    }

    int count = this->_encoder->GetBytes(this->_charBuffer, 0, this->_charPos, 
        this->_byteBuffer, 0, flushEncoder);
    if (count > 0)
        this->_stream->Write(this->_byteBuffer, 0, count);

    this->_charPos = 0;

    if (flushStream)
        this->_stream->Flush();
}

    } // namespace IO
} // namespace Acf