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#ifndef P_STREAM_H
#define P_STREAM_H

#include <string>
#include <iostream>
#include <vector>
#include <fstream>



namespace pst
{
   
    //stream status
    const int  GOOD = 0x0000;
    const int  FAIL = 0x0001;

    //margins ninimum values
    const int MARGINMIN = 3; //millimetres



    template <typename T> class pstreamManip;

    /*!
    \brief class pstream 
    */
    class pstream
    {

    public:
        pstream();
        pstream(std::string whichPrinter);
        ~pstream();

        operator bool()
        {
            return !streamStatus;
        }

        
        void setTitle(std::string newTitle) { title = newTitle; }
        void setPageNumbers(bool bVal)      { pageNumbers = bVal;}
        void setTabSize(int newTabSize)     { tabSize = newTabSize;}
        
        /*!
        The following are member functions NOT manipulators
        */
        void setLeftMargin(int newMargin)   {leftMargin = newMargin <= MARGINMIN? MARGINMIN:newMargin; }
        void setTopMargin(int newMargin)    {topMargin = newMargin <= MARGINMIN? MARGINMIN:newMargin; };
        void setRightMargin(int newMargin)   {rightMargin = newMargin <= MARGINMIN? MARGINMIN:newMargin; };
        void setBottomMargin(int newMargin)   {bottomMargin = newMargin <= MARGINMIN? MARGINMIN:newMargin; };

        
        
        //Insertion Overloads
        //Add a string
        pstream& operator << (std::string name);
        //Add a char buffer
        pstream& operator << (char* name);
        //Add a file
        pstream& operator << (std::ifstream & inFile);

        //other insertion overlaods
        pstream& operator << (pstream & (*ptr)(pstream&)); //manipulator with no parameters
        /*!
        \brief Insertion overload for with manipulators with one parameter
        Note this is a template function so we put the definition here - much easier
        */
        template <typename T>
        pstream& operator << (pstreamManip<T> manip)
        {
            return manip(*this);
        }

        /*!
        \brief Useful static functions
        */
        static std::vector<std::string> getPrinterNames();
        

    private:
        std::string defaultPrinter;
        int streamStatus;
        std::vector<std::string> lines;
        int leftMargin;
        int rightMargin;
        int topMargin;
        int bottomMargin;
        std::string title;
        bool pageNumbers;
        int tabSize;

        
        //Copy Constructor - private and no body
        pstream(const pstream& other);

        
        /*!
        \brief manipulators
        These are mostly friends of pstream.
        They are in the pst namespace
        */
        
        /*!
        \brief Manipulators taking no arguments
        */
        friend pstream& flushp (pstream& p);
        /*!
        \brief manipulators taking one or more arguments
        These are structure based
        */
        
        template <typename T>
        friend pstreamManip<T> setLeftMargin (T margin);

        template <typename T>
        friend pstreamManip<T> setRightMargin (T margin);

        template <typename T>
        friend pstreamManip<T> setTopMargin (T margin);

        template <typename T>
        friend pstreamManip<T> setBottomMargin (T margin);

        /*!
        \brief private  functions for the manipulator(s) with arguments.
        \note These are static.
        */
        static pstream& _setMarginL(pstream & p, int n);
        static pstream& _setMarginR(pstream & p, int n);
        static pstream& _setMarginT(pstream & p, int n);
        static pstream& _setMarginB(pstream & p, int n);

    };//class pstream


    /*!
    \brief The manipulator class for manipulator with one parameter
    */
    template <typename T>
    class pstreamManip 
    {
    public:
        pstreamManip(pstream& (*fp)(pstream&, T val), T arg) : pf(fp), argValue(arg){};
        pstream& operator() (pstream & ps)
        { 
            return (*pf)(ps, argValue);
        }

    private:
        pstream& (*pf)(pstream&, T);
        T argValue;

    }; //class pstream

    /*!
    \brief All manipulators are in the pst namespace
    */
    pstream& flushp (pstream& p);

    
    template <typename T> 
    pstreamManip<T> setLeftMargin (T margin)
    {
        return pstreamManip<T>(pstream::_setMarginL, margin);
    }

    template <typename T> 
    pstreamManip<T> setRightMargin (T margin)
    {
        return pstreamManip<T>(pstream::_setMarginR, margin);
    }

    template <typename T> 
    pstreamManip<T> setTopMargin (T margin)
    {
        return pstreamManip<T>(pstream::_setMarginT, margin);
    }

    template <typename T> 
    pstreamManip<T> setBottomMargin (T margin)
    {
        return pstreamManip<T>(pstream::_setMarginB, margin);
    }


} //namespace pst




#endif 

#undef  UNICODE
#undef _UNICODE

#include "pstream.h"

#include <windows.h>
#include <tchar.h>
#include <iostream>

namespace pst
{

    pstream::pstream() :leftMargin(),rightMargin(),topMargin(),bottomMargin(),tabSize(4),pageNumbers(false)
    {
        DWORD buffSize;
        _TCHAR* pPrinterName;
        GetDefaultPrinter(0, &buffSize);
        pPrinterName = new _TCHAR[buffSize]();
        GetDefaultPrinter (pPrinterName,&buffSize);
        defaultPrinter =  pPrinterName;
        //Set the stream status
        streamStatus = (defaultPrinter == "")? FAIL : GOOD;
    }

    
    pstream::pstream (std::string whichPrinter) :leftMargin(), rightMargin(), topMargin (), bottomMargin(), tabSize(4), pageNumbers(false)
   {
       defaultPrinter = whichPrinter;
       streamStatus = (defaultPrinter == "")? FAIL : GOOD;     
   }

    
    
    pstream::~pstream()
    {

    }


    pstream& pstream::operator <<(std::string name)
    {
        if (! streamStatus)
        {
            //replace all tabs by the required number of spaces
            size_t position =0;

            while (position != std::string::npos)
            {
                
                if (   (position = name.find('\t', position)     ) != std::string::npos    )
                {
                    name.replace(position,1,std::string(tabSize,' ') );
                }

            }

            //We will split the string up at the new line char

            position = 0;
            size_t foundPos =0;

            do
            {
                foundPos = name.find('\n', position);
                std::string str = name.substr(position,foundPos-position);
                lines.push_back(str);
                position = foundPos+1;
            }while (position != 0);
        }
        
        return *this; 
    }   
    
    pstream& pstream::operator <<(char * name)
    {
        if (! streamStatus)
            operator<< (std::string(name));

        return *this;
    }


    pstream& pstream::operator << (std::ifstream & inFile)
    {
        if (!streamStatus)
        {
            if (inFile)
            {
                while (inFile)
                {
                    std::string str;
                    std::getline(inFile,str);

                    *this  << str ;
                }
            }
        }
        return *this;
    }



    pstream& pstream::operator <<(pstream &(*ptr)(pstream &))
    {

        ptr(*this);

        return *this;

    }


    pstream& flushp (pstream& p)
    {
        
        if (!p.lines.size() ||  p.streamStatus )
        {
            return p;
        }
        HDC pdc;

        pdc = CreateDC("winspool",p.defaultPrinter.c_str(),NULL, NULL);

        int logPixelsX, logPixelsY, vRes, hRes, scaleX;

        logPixelsX = GetDeviceCaps(pdc,LOGPIXELSX);
        logPixelsY = GetDeviceCaps(pdc, LOGPIXELSY);
        vRes = GetDeviceCaps(pdc, VERTRES);
        hRes = GetDeviceCaps(pdc, HORZRES);
        scaleX = GetDeviceCaps(pdc,SCALINGFACTORX);

        TEXTMETRIC tm;
        GetTextMetrics(pdc, &tm);
        long aveCharWidth=tm.tmAveCharWidth;
        long maxCharWidth=tm.tmMaxCharWidth;
        long charHeight =tm.tmHeight;
        long lineHeight = charHeight;// + tm.tmExternalLeading;

        //we need to adjust for the margins (change mm to pixels)
        int hPixelsMM = logPixelsX/25;
        int vPixelsMM = logPixelsY/25;
        int leftStart = ( (p.leftMargin*hPixelsMM) > hRes/4)? hRes/4: p.leftMargin*hPixelsMM;
        int rightEnd =  ( (p.rightMargin*hPixelsMM) > hRes/4)? hRes - hRes/4: hRes - p.rightMargin*hPixelsMM;
        int topStart = ( (p.topMargin*vPixelsMM) > vRes/4)? vRes/4: p.topMargin*vPixelsMM;
        int bottomEnd = ( (p.bottomMargin *vPixelsMM) > vRes/4)? vRes - vRes/4: vRes - p.bottomMargin*vPixelsMM;

        //Use 10 point courier font.
        HFONT hFont = CreateFont(-(logPixelsY/72)*10,0,0,0,0,0,0,0,0,0,0,0,FIXED_PITCH,"courier");
        HFONT hOldFont =(HFONT)SelectObject(pdc,hFont);
        

        //start document
        DOCINFO docInfo = {0};
        docInfo.cbSize = sizeof(docInfo);

        StartDoc(pdc,&docInfo);

        //start the pages
        int curPosY = topStart+lineHeight; 
        int curPosX= leftStart;
        int lastSpacePos; //used for word breaking checks

        std::vector<std::string>::iterator iter = p.lines.begin(), iterEnd = p.lines.end();

        StartPage(pdc); //Start the first page
        
        for (; iter != iterEnd ; ++iter )
        {
            std::string curStr = *iter;
            std::string tempStr;
            
            //So for empty lines we will  make the line one space long.
            if(curStr.length() ==0)
                curStr = " ";
            lastSpacePos = 0;
            for (int startIndex = 0,count =0; startIndex < curStr.length() ; count ++)
            {

                int charWidth;
                char c = curStr[count];
                GetCharWidth32(pdc, curStr[count],curStr[count],&charWidth);

                if (count < curStr.length())
                {
                    if(c ==' ')
                        lastSpacePos = count;

                    //check if the character will take us past the right hannd side margin
                    if( (curPosX += charWidth) > rightEnd)
                    {
                        if(lastSpacePos ==startIndex)
                        {
                            lastSpacePos = count-2; //fake a break
                        }
                        tempStr = curStr.substr(startIndex, lastSpacePos-startIndex);
                        count = lastSpacePos;//move the char indexer back to the last space position
                        startIndex = lastSpacePos;
                        //print the line 

                        TextOut(pdc,leftStart,curPosY,tempStr.c_str(), tempStr.length() );

                    }
                    else //No we won't go past RHS margin
                    {
                        continue;              
                    }

                }
                else
                {

                    tempStr = curStr.substr(startIndex, (count)-startIndex);
                    //print
                    TextOut(pdc,leftStart,curPosY,tempStr.c_str(), tempStr.length() );

                    startIndex = count;
                }

                //calculate the next print position - start new page if req'd
                curPosX = leftStart;
                curPosY += lineHeight;
                if (curPosY > bottomEnd)
                {
                    EndPage(pdc);
                    curPosY = topStart+lineHeight;
                    StartPage(pdc);
                }

            }  

        }
    
        EndDoc(pdc);
        p.lines.clear();
        //cleanup
        SelectObject(pdc, hOldFont);
        DeleteObject(hFont);
        DeleteDC(pdc);
        return p;
    }
   
    pstream& pstream:: _setMarginL(pstream & p, int margin)
    {
        p.setLeftMargin(margin);
        return p;
    }  
     
     pstream& pstream:: _setMarginR(pstream & p, int margin)
    {
        p.setRightMargin(margin);
        return p;
    }

    pstream& pstream:: _setMarginT(pstream & p, int margin)
    {
        p.setTopMargin(margin);
        return p;
    }

    pstream& pstream:: _setMarginB(pstream & p, int margin)
    {
        p.setBottomMargin(margin);
        return p;
    }  
        
    std::vector< std::string>  pstream::getPrinterNames()
    {

        LPBYTE buff = 0;
        DWORD buffSize =0;
        DWORD bytesNeeded;
        DWORD numPrinters=0;
        PRINTER_INFO_4 *pInfo;
        std::vector<std::string> names;

        if ( EnumPrinters(PRINTER_ENUM_LOCAL,NULL,4,
                            buff,0,&bytesNeeded,
                            &numPrinters) == FALSE  && bytesNeeded > 0)
        {
            buff = new byte[bytesNeeded];
            EnumPrinters(PRINTER_ENUM_LOCAL,NULL,4,buff,bytesNeeded,&bytesNeeded,&numPrinters);

        }

        pInfo = (PRINTER_INFO_4*)buff;
        for (int count =0; count < numPrinters; count ++)
        {
            names.push_back( std::string (pInfo->pPrinterName));
            ++pInfo;          
        }
   
        delete [] buff;

        return names;

    }

}//namespace pst 

// printer_stream.cpp : Defines the entry point for the console application.


#include "pstream.h"
#include <iostream>
#include <fstream>
#include <windows.h>
#include <string>
#include <iomanip>
using namespace std;




int main(int argc, char* argv[])
{
     
    //The stream has a static function that will  give  the names of the local printers attached to the system;
    vector<string> printerNames = pst::pstream::getPrinterNames();
    vector<string>::iterator itr;
    for (itr = printerNames.begin(); itr != printerNames.end(); ++ itr)
    {
        cout << *itr << '\n';
    }

    
    //Create a stream - default constructor will use the default ptinter
    pst::pstream p;

    //Set the page margins using the printer stream manipulators
    p << pst::setLeftMargin(10);
    p << pst::setTopMargin(20);
    p << pst::setRightMargin(30);
    p << pst::setBottomMargin(-50); //A zero or negative value will clamp to 0;

    //The margins can also be set using the printer stream member functions
    p.setLeftMargin(25);

    
    //We can put strings into the stream
    p << string("This is a very long string with lots of text  way past the eend of"
                "the riiiight margin to test the word break function.");
    p << string("This second string should start on a new line??");

    p << string("This short line\n has embeded newline char(s)");

    p<< string("This line contains\t embedded \t\t tab(s)");

    p << "Alonglinewithnospacestoseewhatwillhappenattheendofthelineabcdefghijklmnopqrstuvwxyz";

    //printing will start when we flush
    p << pst::flushp;

   
    //We can insert files into the stream
    ifstream f("testingx.cpp"); //use some available  text file
    p << f;   
    p << pst::flushp;

    return 0;
}