// Copyright FreeHEP, 2005.

#include "cheprep/DeflateOutputStreamBuffer.h"

/**
 * @author Mark Donszelmann
 * @version $Id: DeflateOutputStreamBuffer.cc,v 1.6 2005/06/02 21:28:45 duns Exp $
 */
namespace cheprep {

    using namespace std;

    unsigned long DeflateOutputStreamBuffer::crctable[] = {
        0x00000000L, 0x77073096L, 0xEE0E612CL, 0x990951BAL,
        0x076DC419L, 0x706AF48FL, 0xE963A535L, 0x9E6495A3L,
        0x0EDB8832L, 0x79DCB8A4L, 0xE0D5E91EL, 0x97D2D988L,
        0x09B64C2BL, 0x7EB17CBDL, 0xE7B82D07L, 0x90BF1D91L,
        0x1DB71064L, 0x6AB020F2L, 0xF3B97148L, 0x84BE41DEL,
        0x1ADAD47DL, 0x6DDDE4EBL, 0xF4D4B551L, 0x83D385C7L,
        0x136C9856L, 0x646BA8C0L, 0xFD62F97AL, 0x8A65C9ECL,
        0x14015C4FL, 0x63066CD9L, 0xFA0F3D63L, 0x8D080DF5L,
        0x3B6E20C8L, 0x4C69105EL, 0xD56041E4L, 0xA2677172L,
        0x3C03E4D1L, 0x4B04D447L, 0xD20D85FDL, 0xA50AB56BL,
        0x35B5A8FAL, 0x42B2986CL, 0xDBBBC9D6L, 0xACBCF940L,
        0x32D86CE3L, 0x45DF5C75L, 0xDCD60DCFL, 0xABD13D59L,
        0x26D930ACL, 0x51DE003AL, 0xC8D75180L, 0xBFD06116L,
        0x21B4F4B5L, 0x56B3C423L, 0xCFBA9599L, 0xB8BDA50FL,
        0x2802B89EL, 0x5F058808L, 0xC60CD9B2L, 0xB10BE924L,
        0x2F6F7C87L, 0x58684C11L, 0xC1611DABL, 0xB6662D3DL,
        0x76DC4190L, 0x01DB7106L, 0x98D220BCL, 0xEFD5102AL,
        0x71B18589L, 0x06B6B51FL, 0x9FBFE4A5L, 0xE8B8D433L,
        0x7807C9A2L, 0x0F00F934L, 0x9609A88EL, 0xE10E9818L,
        0x7F6A0DBBL, 0x086D3D2DL, 0x91646C97L, 0xE6635C01L,
        0x6B6B51F4L, 0x1C6C6162L, 0x856530D8L, 0xF262004EL,
        0x6C0695EDL, 0x1B01A57BL, 0x8208F4C1L, 0xF50FC457L,
        0x65B0D9C6L, 0x12B7E950L, 0x8BBEB8EAL, 0xFCB9887CL,
        0x62DD1DDFL, 0x15DA2D49L, 0x8CD37CF3L, 0xFBD44C65L,
        0x4DB26158L, 0x3AB551CEL, 0xA3BC0074L, 0xD4BB30E2L,
        0x4ADFA541L, 0x3DD895D7L, 0xA4D1C46DL, 0xD3D6F4FBL,
        0x4369E96AL, 0x346ED9FCL, 0xAD678846L, 0xDA60B8D0L,
        0x44042D73L, 0x33031DE5L, 0xAA0A4C5FL, 0xDD0D7CC9L,
        0x5005713CL, 0x270241AAL, 0xBE0B1010L, 0xC90C2086L,
        0x5768B525L, 0x206F85B3L, 0xB966D409L, 0xCE61E49FL,
        0x5EDEF90EL, 0x29D9C998L, 0xB0D09822L, 0xC7D7A8B4L,
        0x59B33D17L, 0x2EB40D81L, 0xB7BD5C3BL, 0xC0BA6CADL,
        0xEDB88320L, 0x9ABFB3B6L, 0x03B6E20CL, 0x74B1D29AL,
        0xEAD54739L, 0x9DD277AFL, 0x04DB2615L, 0x73DC1683L,
        0xE3630B12L, 0x94643B84L, 0x0D6D6A3EL, 0x7A6A5AA8L,
        0xE40ECF0BL, 0x9309FF9DL, 0x0A00AE27L, 0x7D079EB1L,
        0xF00F9344L, 0x8708A3D2L, 0x1E01F268L, 0x6906C2FEL,
        0xF762575DL, 0x806567CBL, 0x196C3671L, 0x6E6B06E7L,
        0xFED41B76L, 0x89D32BE0L, 0x10DA7A5AL, 0x67DD4ACCL,
        0xF9B9DF6FL, 0x8EBEEFF9L, 0x17B7BE43L, 0x60B08ED5L,
        0xD6D6A3E8L, 0xA1D1937EL, 0x38D8C2C4L, 0x4FDFF252L,
        0xD1BB67F1L, 0xA6BC5767L, 0x3FB506DDL, 0x48B2364BL,
        0xD80D2BDAL, 0xAF0A1B4CL, 0x36034AF6L, 0x41047A60L,
        0xDF60EFC3L, 0xA867DF55L, 0x316E8EEFL, 0x4669BE79L,
        0xCB61B38CL, 0xBC66831AL, 0x256FD2A0L, 0x5268E236L,
        0xCC0C7795L, 0xBB0B4703L, 0x220216B9L, 0x5505262FL,
        0xC5BA3BBEL, 0xB2BD0B28L, 0x2BB45A92L, 0x5CB36A04L,
        0xC2D7FFA7L, 0xB5D0CF31L, 0x2CD99E8BL, 0x5BDEAE1DL,
        0x9B64C2B0L, 0xEC63F226L, 0x756AA39CL, 0x026D930AL,
        0x9C0906A9L, 0xEB0E363FL, 0x72076785L, 0x05005713L,
        0x95BF4A82L, 0xE2B87A14L, 0x7BB12BAEL, 0x0CB61B38L,
        0x92D28E9BL, 0xE5D5BE0DL, 0x7CDCEFB7L, 0x0BDBDF21L,
        0x86D3D2D4L, 0xF1D4E242L, 0x68DDB3F8L, 0x1FDA836EL,
        0x81BE16CDL, 0xF6B9265BL, 0x6FB077E1L, 0x18B74777L,
        0x88085AE6L, 0xFF0F6A70L, 0x66063BCAL, 0x11010B5CL,
        0x8F659EFFL, 0xF862AE69L, 0x616BFFD3L, 0x166CCF45L,
        0xA00AE278L, 0xD70DD2EEL, 0x4E048354L, 0x3903B3C2L,
        0xA7672661L, 0xD06016F7L, 0x4969474DL, 0x3E6E77DBL,
        0xAED16A4AL, 0xD9D65ADCL, 0x40DF0B66L, 0x37D83BF0L,
        0xA9BCAE53L, 0xDEBB9EC5L, 0x47B2CF7FL, 0x30B5FFE9L,
        0xBDBDF21CL, 0xCABAC28AL, 0x53B39330L, 0x24B4A3A6L,
        0xBAD03605L, 0xCDD70693L, 0x54DE5729L, 0x23D967BFL,
        0xB3667A2EL, 0xC4614AB8L, 0x5D681B02L, 0x2A6F2B94L,
        0xB40BBE37L, 0xC30C8EA1L, 0x5A05DF1BL, 0x2D02EF8DL
    };

    DeflateOutputStreamBuffer::DeflateOutputStreamBuffer(streambuf *buffer) 
            : buffer(buffer)
              , crc(0)
              , size(0)
#ifndef CHEPREP_NO_ZLIB               
              , zStreamOpen(false)
              , in(inSize)
              , out(outSize) 
#endif // CHEPREP_NO_ZLIB
              {
        
#ifndef CHEPREP_NO_ZLIB
        zStream.zalloc = Z_NULL;
        zStream.zfree = Z_NULL;
        zStream.opaque = Z_NULL;
#endif // CHEPREP_NO_ZLIB
    }
        

    void DeflateOutputStreamBuffer::init(bool compress) {

#ifndef CHEPREP_NO_ZLIB        
        if (compress) {
            if (zStreamOpen) return;
            
            zStream.next_in = reinterpret_cast<unsigned char *>(&(in[0]));
            zStream.avail_in = 0 ;
    
            zStream.next_out = reinterpret_cast<unsigned char *>(&(out[0]));
            zStream.avail_out = out.size();
    
            if (deflateInit2(&zStream, 6, Z_DEFLATED, -MAX_WBITS, 8, Z_DEFAULT_STRATEGY ) != Z_OK) {
                cerr << "ERROR: deflateInit2 failed" << endl;
            } else {
                zStreamOpen = true;
                setp(&(in[0]), &(in[0])+inSize);
            }
        }
#else
        // suppress warning about unused var
        compress = false;
#endif // CHEPREP_NO_ZLIB

        crc = 0;
        size = 0;
    }
    
    void DeflateOutputStreamBuffer::finish() {

#ifndef CHEPREP_NO_ZLIB        
        if (zStreamOpen) {

            overflow() ;

            zStream.next_out  = reinterpret_cast<unsigned char *>(&(out[0]));
            zStream.avail_out = outSize;
    
            int err = Z_OK ;
            while ( err == Z_OK ) {
                if (zStream.avail_out == 0) {
                    flushOut();
                }
                err = deflate(&zStream, Z_FINISH);
            }
        
            flushOut() ;
    
            if (err != Z_STREAM_END) {
                cerr << "ERROR: deflation failed" << endl;
            }
    
            if (deflateEnd(&zStream) != Z_OK) {
                cerr << "ERROR: deflateEnd failed" << endl;
            }
            
            zStreamOpen = false ;
        }      
#endif // CHEPREP_NO_ZLIB
    }
                
    DeflateOutputStreamBuffer::~DeflateOutputStreamBuffer() {
    }


#ifndef CHEPREP_NO_ZLIB        
    #define DO1 crc = crctable[(crc ^ (*buf++)) & 0xff] ^ (crc >> 8)
    #define DO8 DO1; DO1; DO1; DO1; DO1; DO1; DO1; DO1
#endif // CHEPREP_NO_ZLIB


    int DeflateOutputStreamBuffer::overflow(int c) {

#ifndef CHEPREP_NO_ZLIB        
        if (zStreamOpen) {
            zStream.avail_in = pptr() - pbase() ;
            zStream.next_in = reinterpret_cast<unsigned char *>(&(in[0]));
        
            int len = zStream.avail_in;
            unsigned char* buf = zStream.next_in;
        
            crc = crc ^ 0xffffffffUL;
            while (len >= 8) {
                DO8;
                len -= 8;
            }
            if (len) do {
                DO1;
            } while (--len);
            crc = crc ^ 0xffffffffUL;
    
            size += zStream.avail_in;

            zStream.next_out  = reinterpret_cast<unsigned char *>(&(out[0]));
            zStream.avail_out = outSize ;
        
            int err = Z_OK ;
            while ((zStream.avail_in > 0 || zStream.avail_out == 0) && err == Z_OK) {
                if (zStream.avail_out == 0 ) {
                    flushOut();
                }
                err = deflate(&zStream, Z_NO_FLUSH);
            }

            flushOut();
        
            setp(&(in[0]), &(in[0]) + inSize);

            if ((err != Z_OK) && (err != Z_STREAM_END)) {
                cerr << "ERROR: deflation failed" << endl;
                return EOF ;
            }

            if ( c != EOF ) {
                *pptr() = c ;
                pbump(1);
            }
    
            return 0 ;
        } else {
#endif // CHEPREP_NO_ZLIB
            crc = crc ^ 0xffffffffUL;
            crc = crctable[(crc ^ c) & 0xff] ^ (crc >> 8);
            crc = crc ^ 0xffffffffUL;
            size++;
            return buffer->sputc((char)c);
#ifndef CHEPREP_NO_ZLIB        
        }
#endif // CHEPREP_NO_ZLIB
    }
    

#ifndef CHEPREP_NO_ZLIB        
    bool DeflateOutputStreamBuffer::flushOut() {
        int deflatedCount = outSize - zStream.avail_out;
        int byteCount = buffer->sputn(&(out[0]), deflatedCount);

        zStream.next_out = reinterpret_cast<unsigned char *>(&(out[0]));
        zStream.avail_out = outSize ;

        return deflatedCount == byteCount ;
    }
#endif // CHEPREP_NO_ZLIB
    
} // cheprep
