gclib/tophat_cpp/bwt_map.cpp

/*
 *  bwt_map.cpp
 *  TopHat
 *
 *  Created by Cole Trapnell on 11/17/08.
 *  Copyright 2008 Cole Trapnell. All rights reserved.
 *
 */

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include <cassert>
#include <cstdlib>
#include <iostream>
#include <set>
#include <vector>
#include <cmath>

#include "common.h"
#include "bwt_map.h"
#include "tokenize.h"
#include "reads.h"

using namespace std;

void HitTable::add_hit(const BowtieHit& bh, bool check_uniqueness)
{
        uint32_t reference_id = bh.ref_id();
        
        pair<RefHits::iterator, bool> ret = 
        _hits_for_ref.insert(make_pair(reference_id, HitList()));
        HitList& hl = ret.first->second;

        if (check_uniqueness)
        {
                // Check uniqueness, in case we are adding spliced hits from 
                // several spliced alignment sources (e.g. de novo hashing + Bowtie 
                // against a user-supplied index).  We don't want to count the same
                // alignment twice if it happened to be found by more than one method
                HitList::const_iterator lb = lower_bound(hl.begin(), hl.end(), bh, hit_insert_id_lt);   
                HitList::const_iterator ub = upper_bound(hl.begin(), hl.end(), bh, hit_insert_id_lt); 
                for (; lb != ub && lb != hl.end(); ++lb)
                {
                        if (*lb == bh)
                        {
                                //fprintf(stderr, "Chucking duplicate read %d by identity\n", bh.insert_id());
                                return;
                        }
                        
                        if (lb->insert_id() == bh.insert_id() &&
                                lb->ref_id() == bh.ref_id() &&
                                lb->antisense_align() == bh.antisense_align())
                        {
                                // If we get here, we may be looking at the same alignment
                                // However, spanning_reads may report a shorter, trimmed alignment
                                // so not all fields will be equal.  If they just disagree on the 
                                // ends, and don't indicate a different junction coord, the 
                                // alignments are the same.

                                if ((lb->left() <= bh.left() && lb->right() >= bh.right()) ||
                                        (bh.left() <= lb->left() && bh.right() >= lb->right()))
                                {
                                        vector<pair<int,int> > lb_gaps, bh_gaps;
                                        lb->gaps(lb_gaps);
                                        bh.gaps(bh_gaps);
                                        if (lb_gaps == bh_gaps)
                                        {
                                                // One alignment is contained in the other, they agree on 
                                                // where the gaps, if any, are, and they share an id
                                                // => this is a redundant aligment, so toss it
                                                //fprintf(stderr, "Chucking duplicate read %d by gap agreement\n", bh.insert_id());
                                                return;
                                        }
                                }
                        }
                }
        }
        _total_hits++;
        hl.push_back(bh);
}

bool hit_insert_id_lt(const BowtieHit& h1, const BowtieHit& h2)
{
        return h1.insert_id() < h2.insert_id();
}

void LineHitFactory::openStream(HitStream& hs)
{
 if (hs._hit_file==NULL && !hs._hit_file_name.empty()) {
    //open the file for HitStream here
   hs._hit_file=fopen(hs._hit_file_name.c_str(),"r");
    if (hs._hit_file==NULL)
      err_die("Error opening HitStream file %s\n",hs._hit_file_name.c_str());
    return;
    }
 if (hs._fzpipe!=NULL) {
   hs._hit_file=hs._fzpipe->file;
   }
}

void LineHitFactory::rewind(HitStream& hs)
{
  if (hs._fzpipe!=NULL) {
        hs._fzpipe->rewind();
        hs._hit_file=hs._fzpipe->file;
        }
      else if (hs._hit_file) ::rewind((FILE*)(hs._hit_file));
}

bool LineHitFactory::next_record(HitStream& hs, const char*& buf, size_t& buf_size) {
     FILE* f=(FILE *)(hs._hit_file);
     bool new_rec = (fgets(_hit_buf,  _hit_buf_max_sz - 1, f)!=NULL);
     if (!new_rec || feof(f)) {
             hs._eof=true;
             return false;
             }
     ++_line_num;
     char* nl = strrchr(_hit_buf, '\n');
     if (nl) *nl = 0;
     buf = _hit_buf;
     buf_size = _hit_buf_max_sz - 1;
     return true;
     }

void LineHitFactory::closeStream(HitStream& hs) {
  if (hs._fzpipe!=NULL) {
     hs._fzpipe->close();
     return;
     }
  if (hs._hit_file!=NULL) {
    fclose((FILE*)(hs._hit_file));
    hs._hit_file=NULL;
    }
}
void BAMHitFactory::openStream(HitStream& hs) {
  if (hs._hit_file==NULL) {
     if (hs._hit_file_name.empty())
         //err_die("Error: invalid HitStream set for BAMHitFactory(file name missing)\n");
         return; //invalid stream, could be just a place holder
     //open the file here if not already open
     string fext=getFext(hs._hit_file_name);
     if (fext=="sam")
          hs._hit_file = samopen(hs._hit_file_name.c_str(), "r", 0);
        else
          hs._hit_file = samopen(hs._hit_file_name.c_str(), "rb", 0);

     samfile_t* sam_file=(samfile_t*)(hs._hit_file);

     if (sam_file == NULL)
         err_die("Error opening SAM file %s\n", hs._hit_file_name.c_str());
     if (sam_file->header == NULL)
         err_die("Error: no SAM header found for file %s\n", hs._hit_file_name.c_str());
     memset(&_next_hit, 0, sizeof(_next_hit));
     //_beginning = bgzf_tell(sam_file->x.bam);
     _sam_header=sam_file->header;
     if (inspect_header(hs) == false)
         err_die("Error: invalid SAM header for file %s\n",
                 hs._hit_file_name.c_str());
     }
}

void BAMHitFactory::closeStream(HitStream& hs) {
  if (hs._hit_file) {
        samclose((samfile_t*)(hs._hit_file));
        }
  hs._hit_file=NULL;
  _sam_header=NULL;
}

void BAMHitFactory::rewind(HitStream& hs)
{
  /*
    if (_hit_file && ((samfile_t*)_hit_file)->x.bam)
    {
        bgzf_seek(((samfile_t*)_hit_file)->x.bam, _beginning, SEEK_SET);
         _eof = false;
    }
    */
  this->closeStream(hs);
  this->openStream(hs);
}

string BAMHitFactory::hitfile_rec(HitStream& hs, const char* hit_buf) {
  const bam1_t* bamrec=(const bam1_t*)hit_buf;
  char* tamline=bam_format1(((samfile_t*)(hs._hit_file))->header, bamrec);
  string sam_line(tamline);
  free(tamline);
  return sam_line;
  }

bool BAMHitFactory::next_record(HitStream& hs, const char*& buf, size_t& buf_size) {
  if (_next_hit.data) {
      free(_next_hit.data);
      _next_hit.data = NULL;
      }
  _sam_header=((samfile_t*)(hs._hit_file))->header; //needed by get_hit_from_buf later on
  if (hs.eof() || !hs.ready()) return false;

  //mark_curr_pos();

  memset(&_next_hit, 0, sizeof(_next_hit));

  int bytes_read = samread((samfile_t*)(hs._hit_file), &_next_hit);
  if (bytes_read <= 0) {
      hs._eof = true;
      return false;
      }
  buf = (const char*)&_next_hit;
  buf_size = bytes_read;
  return true;
  }


BowtieHit HitFactory::create_hit(const string& insert_name, 
                                 const string& ref_name,
                                 int left,
                                 const vector<CigarOp>& cigar,
                                 bool antisense_aln,
                                 bool antisense_splice,
                                 unsigned char edit_dist,
                                 unsigned char splice_mms,
                                 bool end)
{
        uint64_t insert_id = _insert_table.get_id(insert_name);
        uint32_t reference_id = _ref_table.get_id(ref_name, NULL, 0);
        
        return BowtieHit(reference_id,
                         insert_id, 
                         left, 
                         cigar, 
                         antisense_aln,
                         antisense_splice,
                         edit_dist,
                         splice_mms,
                         end);
}

BowtieHit HitFactory::create_hit(const string& insert_name, 
                                 const string& ref_name,
                                 uint32_t left,
                                 uint32_t read_len,
                                 bool antisense_aln,
                                 unsigned char edit_dist,
                                 bool end)
{
        uint64_t insert_id = _insert_table.get_id(insert_name);
        uint32_t reference_id = _ref_table.get_id(ref_name, NULL, 0);
        
        return BowtieHit(reference_id,
                         insert_id, 
                         left,
                         read_len,
                         antisense_aln,
                         edit_dist,
                         end);  
}

bool BowtieHitFactory::get_hit_from_buf(const char* orig_bwt_buf, 
                                        BowtieHit& bh,
                                        bool strip_slash,
                                        char* name_out,
                                        char* name_tags,
                                        char* seq,
                                        char* qual)
{
        if (!orig_bwt_buf || !*orig_bwt_buf)
                return false;
        
        static const int buf_size = 2048;
        
        char bwt_buf[buf_size];
        strcpy(bwt_buf, orig_bwt_buf);
        //const char* bwt_fmt_str = "%s %c %s %d %s %s %d %s";

        char orientation;
        
        //int bwtf_ret = 0;
        //uint32_t seqid = 0;
        
        char text_name[buf_size];
        unsigned int text_offset;
        
        
        //unsigned int other_occs;
        char mismatches[buf_size];
        //memset(mismatches, 0, sizeof(mismatches));
        
        const char* buf = bwt_buf;
        char* name = get_token((char**)&buf,"\t");
        char* orientation_str = get_token((char**)&buf,"\t");
        char* text_name_str = get_token((char**)&buf,"\t");
        
        strcpy(text_name, text_name_str);
        
        char* text_offset_str = get_token((char**)&buf,"\t");
        char* seq_str = get_token((char**)&buf,"\t");
        if (seq)
          strcpy(seq, seq_str);
        
        const char* qual_str = get_token((char**)&buf,"\t");
        if (qual)
          strcpy(qual, qual_str);
        
        /*const char* other_occs_str =*/ get_token((char**)&buf, "\t");
        mismatches[0] = 0;
        char* mismatches_str = get_token((char**)&buf, "\t");
        if (mismatches_str)
                strcpy(mismatches, mismatches_str);
        
        orientation = orientation_str[0];
        text_offset = atoi(text_offset_str);

        bool end = true;
        unsigned int seg_offset = 0;
        unsigned int seg_num = 0;
        unsigned int num_segs = 0;
        
        // Copy the tag out of the name field before we might wipe it out
        char* pipe = strrchr(name, '|');
        if (pipe)
        {
                if (name_tags)
                  strcpy(name_tags, pipe);

                char* tag_buf = pipe + 1;
                if (strchr(tag_buf, ':'))
                  {
                    sscanf(tag_buf, "%u:%u:%u", &seg_offset, &seg_num, &num_segs);
                    if (seg_num + 1 == num_segs)
                      end = true;
                    else
                      end = false;
                  }
                
                *pipe = 0;
        }
        // Stripping the slash and number following it gives the insert name
        char* slash = strrchr(name, '/');
        if (strip_slash && slash)
                *slash = 0;
        
        size_t read_len = strlen(seq_str);
        
        // Add this alignment to the table of hits for this half of the
        // Bowtie map

        //vector<string> mismatch_toks;
        char* pch = strtok (mismatches,",");
        unsigned char num_mismatches = 0;
        while (pch != NULL)
        {
                char* colon = strchr(pch, ':');
                if (colon) 
                {
                        num_mismatches++;
                }
                //mismatch_toks.push_back(pch);
                pch = strtok (NULL, ",");
        }
        
        bh = create_hit(name,
                        text_name,
                        text_offset, 
                        (int)read_len, 
                        orientation == '-',
                        num_mismatches,
                        end);
        
        return true;
}

int anchor_mismatch = 0;


void parseSegReadName(char* name, char*& name_tags, bool strip_slash,
                bool &end, unsigned int &seg_offset, unsigned int& seg_num,
                                                   unsigned int & num_segs) {
        char* pipe = strrchr(name, '|');
        if (pipe)
        {
                if (name_tags)
                        strcpy(name_tags, pipe);

                char* tag_buf = pipe + 1;
                if (strchr(tag_buf, ':'))
                  {
                        sscanf(tag_buf, "%u:%u:%u", &seg_offset, &seg_num, &num_segs);
                        if (seg_num + 1 == num_segs)
                          end = true;
                        else
                          end = false;
                  }

                *pipe = 0;
        }

        // Stripping the slash and number following it gives the insert name
        char* slash = strrchr(name, '/');
        if (strip_slash && slash)
                *slash = 0;
}


bool SplicedBowtieHitFactory::get_hit_from_buf(const char* orig_bwt_buf, 
                                               BowtieHit& bh,
                                               bool strip_slash,
                                               char* name_out,
                                               char* name_tags,
                                               char* seq,
                                               char* qual)
{
        if (!orig_bwt_buf || !*orig_bwt_buf)
                return false;
        
        static const int buf_size = 2048;
        
        char bwt_buf[buf_size];
        strcpy(bwt_buf, orig_bwt_buf);
        //const char* bwt_fmt_str = "%s %c %s %d %s %s %d %s";

        char orientation;
        char text_name[buf_size];
        unsigned int text_offset;
        char mismatches[buf_size];
        //memset(mismatches, 0, sizeof(mismatches));

        char* buf = bwt_buf;
        char* name = get_token((char**)&buf,"\t");
        char* orientation_str = get_token((char**)&buf,"\t");
        char* text_name_str = get_token((char**)&buf,"\t");
        strcpy(text_name, text_name_str);
        
        char* text_offset_str = get_token((char**)&buf,"\t");
        char* seq_str = get_token((char**)&buf,"\t");
        if (seq)
          strcpy(seq, seq_str);
        
        const char* qual_str = get_token((char**)&buf,"\t");
        if (qual)
          strcpy(qual, qual_str);
        
        /*const char* other_occs_str =*/ get_token((char**)&buf, "\t");
        mismatches[0] = 0;
        char* mismatches_str = get_token((char**)&buf, "\t");
        if (mismatches_str)
                strcpy(mismatches, mismatches_str);
        
        orientation = orientation_str[0];
        text_offset = atoi(text_offset_str);
        
        bool end = true;
        unsigned int seg_offset = 0;
        unsigned int seg_num = 0;
        unsigned int num_segs = 0;

        // Copy the tag out of the name field before we might wipe it out
        parseSegReadName(name, name_tags, strip_slash, end, seg_offset, seg_num, num_segs);

        // Add this alignment to the table of hits for this half of the
        // Bowtie map

        // Parse the text_name field to recover the splice coords
        vector<string> toks;
        
        tokenize_strict(text_name, "|", toks);
        
        int num_extra_toks = (int)toks.size() - 6;
        
        if (num_extra_toks >= 0)
        {
                static const uint8_t left_window_edge_field = 1;
                static const uint8_t splice_field = 2;
                //static const uint8_t right_window_edge_field = 3;
                static const uint8_t junction_type_field = 4;
                static const uint8_t strand_field = 5;
                
                string contig = toks[0];
                for (int t = 1; t <= num_extra_toks; ++t)
                {
                        contig += "|";
                        contig += toks[t];
                }
                
                vector<string> splice_toks;
                tokenize(toks[num_extra_toks + splice_field], "-", splice_toks);
                if (splice_toks.size() != 2)
                {                       
                        fprintf(stderr, "Warning: found malformed splice record, skipping:\n");
                        //fprintf(stderr, "%s (token: %s)\n", text_name, 
                        //        toks[num_extra_toks + splice_field].c_str());
                        return false;                   
                }

                //
                // check for an insertion hit
                //
                if(toks[num_extra_toks + junction_type_field] == "ins")
                  {
                        int8_t spliced_read_len = strlen(seq_str);
                        /*
                         * The 0-based position of the left edge of the alignment. Note that this
                         * value may need to be futher corrected to account for the presence of
                         * of the insertion.  
                        */
                        uint32_t left = atoi(toks[num_extra_toks + left_window_edge_field].c_str()) + text_offset;
                        uint32_t right = left + spliced_read_len - 1;


                        /*
                         * The 0-based position of the last genomic sequence before the insertion
                         */
                        uint32_t left_splice_pos = atoi(splice_toks[0].c_str());
                
                        string insertedSequence = splice_toks[1];
                        /*
                         * The 0-based position of the first genomic sequence after teh insertion
                         */
                        uint32_t right_splice_pos = left_splice_pos + 1; 
                        if(left > left_splice_pos){
                                /*
                                 * The genomic position of the left edge of the alignment needs to be corrected
                                 * If the alignment does not extend into the insertion, simply subtract the length
                                 * of the inserted sequence, otherwise, just set it equal to the right edge
                                 */
                                left = left - insertedSequence.length();
                                if(left < right_splice_pos){
                                        left = right_splice_pos;
                                }
                        }
                        if(right > left_splice_pos){
                                right = right - insertedSequence.length();
                                if(right < left_splice_pos){
                                        right = left_splice_pos;
                                }
                        }
                        /*
                         * Now, right and left should be properly transformed into genomic coordinates
                         * We should be able to deduce how much the alignment matches the insertion
                         * simply based on the length of the read
                         */
                        int left_match_length = 0;
                        if(left <= left_splice_pos){
                                left_match_length = left_splice_pos - left + 1;
                        }
                        int right_match_length = 0;
                        if(right >= right_splice_pos){
                                right_match_length = right - right_splice_pos + 1;
                        }
                        int insertion_match_length = spliced_read_len - left_match_length - right_match_length;

                        if(left_match_length <= 0 || right_match_length <= 0 || insertion_match_length <= 0)
                          return false;

                        string junction_strand = toks[num_extra_toks + strand_field];
                        if(junction_strand != "rev" && junction_strand != "fwd"){
                                fprintf(stderr, "Malformed insertion record\n");
                                return false;
                        }
                        
                        char* pch = strtok( mismatches, ",");
                        unsigned char num_mismatches = 0;

                        /*
                         * remember that text_offset holds the left end of the 
                         * alignment, relative to the start of the contig
                         */

                        /*
                         * The 0-based relative position of the left-most character
                         * before the insertion in the contig
                         */
                        int relative_splice_pos = left_splice_pos - atoi(toks[num_extra_toks + left_window_edge_field].c_str()); 
                        while (pch != NULL)
                        {
                                char* colon = strchr(pch, ':');
                                if (colon) 
                                {
                                        *colon = 0;
                                        int mismatch_pos = atoi(pch);

                                        /*
                                         * for reversely mapped reads,
                                         * find the correct mismatched position.
                                         */
                                        if(orientation == '-'){
                                          mismatch_pos = spliced_read_len - mismatch_pos - 1;
                                        }

                                        /*
                                         * Only count mismatches outside of the insertion region
                                         * If there is a mismatch within the insertion,
                                         * disallow this hit 
                                         */
                                        if(mismatch_pos + text_offset <= relative_splice_pos || mismatch_pos + text_offset > relative_splice_pos + insertedSequence.length()){
                                          num_mismatches++;
                                        }else{
                                          return false; 
                                        }
                                }
                                pch = strtok (NULL, ",");
                        }
                        
                        
                        vector<CigarOp> cigar;
                        cigar.push_back(CigarOp(MATCH, left_match_length));
                        cigar.push_back(CigarOp(INS, insertion_match_length)); 
                        cigar.push_back(CigarOp(MATCH, right_match_length)); 

                        /*
                         * For now, disallow hits that don't span
                         * the insertion. If we allow these types of hits,
                         * then long_spanning.cpp needs to be updated
                         * in order to intelligently merge these kinds
                         * of reads back together
                         * 
                         * Following code has been changed to allow segment that end
                         * in an insertion
                         */
                        bh = create_hit(name,
                                        contig,
                                        left, 
                                        cigar,
                                        orientation == '-', 
                                        junction_strand == "rev",
                                        num_mismatches,
                                        0,
                                        end);
                        return true;
                }       

                else
                  {
                    uint32_t left = atoi(toks[num_extra_toks + left_window_edge_field].c_str()) + text_offset;
                    int spliced_read_len = strlen(seq_str);
                    int8_t left_splice_pos = atoi(splice_toks[0].c_str()) - left + 1;
                    if(left_splice_pos > spliced_read_len) left_splice_pos = spliced_read_len;            
                    int8_t right_splice_pos = spliced_read_len - left_splice_pos;
                    
                    if (right_splice_pos <= 0 || left_splice_pos <= 0)
                      return false;
                    
                    if (orientation == '+')
                      {
                        if (left_splice_pos + seg_offset < _anchor_length){
                          return false;
                        }
                      }
                    else
                      {
                        if (right_splice_pos + seg_offset < _anchor_length)
                          return false;
                      }
                    //uint32_t right = atoi(splice_toks[1].c_str()) + right_splice_pos;
                    //atoi(toks[right_window_edge_field].c_str());
                    int gap_len = atoi(splice_toks[1].c_str()) - atoi(splice_toks[0].c_str()) - 1;
                    
                    string junction_strand = toks[num_extra_toks + strand_field];
                    if (!(junction_strand == "rev" || junction_strand == "fwd")||
                        !(orientation == '-' || orientation == '+'))
                      {
                        fprintf(stderr, "Warning: found malformed splice record, skipping\n");
                        //fprintf(stderr, "junction_strand=%s, orientation='%c'\n",
                        //           junction_strand.c_str(), orientation);
                        return false;
                      }
                    
                    //vector<string> mismatch_toks;
                    char* pch = strtok (mismatches,",");
                    int mismatches_in_anchor = 0;
                    unsigned char num_mismatches = 0;
                    while (pch != NULL)
                      {
                        char* colon = strchr(pch, ':');
                        if (colon) 
                          {
                            *colon = 0;
                            num_mismatches++;
                            int mismatch_pos = atoi(pch);
                            if ((orientation == '+' && abs(mismatch_pos - left_splice_pos) < (int)min_anchor_len) ||
                                (orientation == '-' && abs(((int)spliced_read_len - left_splice_pos + 1) - mismatch_pos)) < (int)min_anchor_len)
                              mismatches_in_anchor++;
                          }
                        //mismatch_toks.push_back(pch);
                        pch = strtok (NULL, ",");
                      }
                    
                    // FIXME: we probably should exclude these hits somewhere, but this
                    // isn't the right place
                    vector<CigarOp> cigar;
                    cigar.push_back(CigarOp(MATCH, left_splice_pos));
                    if(toks[num_extra_toks + junction_type_field] == "del"){
                      cigar.push_back(CigarOp(DEL, gap_len));
                    }else{
                      cigar.push_back(CigarOp(REF_SKIP, gap_len));
                    }
                    cigar.push_back(CigarOp(MATCH, right_splice_pos));
                    
                    bh = create_hit(name,
                                    contig,
                                    left, 
                                    cigar,
                                    orientation == '-', 
                                    junction_strand == "rev",
                                    num_mismatches,
                                    mismatches_in_anchor,
                                    end);
                    return true;
                  }
        }
        else
        {
          fprintf(stderr, "Warning: found malformed splice record, skipping\n");
          //fprintf(stderr, "%s\n", orig_bwt_buf);
          //                    continue;
                return false;
        }

        return false;
}


int parseCigar(vector<CigarOp>& cigar, const char* cigar_str,
                bool &spliced_alignment)   {
const char* p_cig = cigar_str;
int refspan=0; //alignment span on reference sequence
while (*p_cig)
{
        char* t;
        int op_len = (int)strtol(p_cig, &t, 10);
        if (op_len <= 0)
        {
                fprintf (stderr, "Error: CIGAR op has zero length\n");
                return 0;
        }
        char op_char = toupper(*t);
        CigarOpCode opcode;
        switch (op_char) {
          case '=':
          case 'X':
          case 'M': opcode = MATCH;
                    refspan+=op_len;
                    break;
          case 'I': opcode = INS;
                    break;
    case 'D': opcode = DEL;
              refspan+=op_len;
              break;
    case 'N': if (op_len > max_report_intron_length)
                  return 0;
              opcode = REF_SKIP;
              spliced_alignment = true;
              refspan+=op_len;
              break;
    case 'S': opcode = SOFT_CLIP;
              break;
    case 'H': opcode = HARD_CLIP;
              break;
    case 'P': opcode = PAD;
              break;
    default:  fprintf (stderr, "Error: invalid CIGAR operation\n");
                          return 0;
          }
        p_cig = t + 1;
        cigar.push_back(CigarOp(opcode, op_len));
} //while cigar codes
if (*p_cig) {
          fprintf (stderr, "Error: unmatched CIGAR operation (%s)\n",p_cig);
          return 0;
    }
return refspan;
}

int getSAMmismatches(char* &buf, vector<CigarOp>& cigar,
                  vector<int>& mismatches, int& sam_nm, bool& antisense_splice) {
  int gspan=0;//genomic span of the alignment
  const char* tag_buf = buf;
        sam_nm=0;
        //num_mismatches=0;
        while((tag_buf = get_token((char**)&buf,"\t")))
        {
                vector<string> tuple_fields;
                tokenize(tag_buf,":", tuple_fields);
                if (tuple_fields.size() == 3)
                {
                        if (tuple_fields[0] == "XS")
                        {
                                if (tuple_fields[2] == "-")
                                        antisense_splice = true;
                        }
                        else if (tuple_fields[0] == "NM")
                        {
                                sam_nm = atoi(tuple_fields[2].c_str());
                        }
                        else if (tuple_fields[0] == "NS")
                        {
                                //ignored for now
                        }
                        else if (tuple_fields[0] == "MD")
                        {
              const char* p=tuple_fields[2].c_str();
              int bi=0; //base offset position in the read
              while (*p != 0) {
                if (isdigit(*p)) {
                  int v=atoi(p);
                  do { p++; } while (isdigit(*p));
                  bi+=v;
                  }
                 while (isalpha(*p)) {
                  p++;
                  mismatches.push_back(bi);
                  bi++;
                  }
                 if (*p=='^') { //reference deletion
                   p++;
                   while (isalpha(*p)) { //insert read bases
                          p++; bi++;
                    }
                   }
                }
                        }
                        else
                        {
                                //fprintf(stderr, "%s attribute not supported\n", tuple_fields[0].c_str());
                                //return false;
                        }
                }
        }
         /* By convention,the NM field of the SAM record
         *  counts an insertion or deletion. I dont' think
         *  we want the mismatch count in the BowtieHit
         *  record to reflect this. Therefore, subtract out
         *  the mismatches due to in/dels
         */
        for(vector<CigarOp>::const_iterator itr = cigar.begin(); itr != cigar.end(); ++itr){
    switch (itr->opcode)
    {
      case MATCH:
      case REF_SKIP:
      case PAD:
        gspan += itr->length;
        break;
      case DEL:
        gspan += itr->length;
        sam_nm -= itr->length;
        break;
      case INS:
        sam_nm -= itr->length;
        break;
                }
         }
        return gspan;
}

bool SAMHitFactory::get_hit_from_buf(const char* orig_bwt_buf, 
                                     BowtieHit& bh,
                                     bool strip_slash,
                                     char* name_out,
                                     char* name_tags,
                                     char* seq,
                                     char* qual)
{
        if (!orig_bwt_buf || !*orig_bwt_buf)
                return false;
        char bwt_buf[2048];
        strcpy(bwt_buf, orig_bwt_buf);
        // Are we still in the header region?
        if (bwt_buf[0] == '@')
                return false;
        
        char* buf = bwt_buf;
        char* name = get_token((char**)&buf,"\t");
        char* sam_flag_str = get_token((char**)&buf,"\t");
        char* text_name = get_token((char**)&buf,"\t");
        char* text_offset_str = get_token((char**)&buf,"\t");
        const char* map_qual_str = get_token((char**)&buf,"\t");
        char* cigar_str = get_token((char**)&buf,"\t");
        const char* mate_ref_str =  get_token((char**)&buf,"\t");
        const char* mate_pos_str =  get_token((char**)&buf,"\t");
        const char* inferred_insert_sz_str =  get_token((char**)&buf,"\t");
        
        const char* seq_str =  get_token((char**)&buf,"\t");
        if (seq)
          strcpy(seq, seq_str);
        
        const char* qual_str =  get_token((char**)&buf,"\t");
        if (qual)
          strcpy(qual, qual_str);
        
        if (!name ||
                !sam_flag_str ||
                !text_name ||
                !text_offset_str ||
                !map_qual_str ||
                !cigar_str ||
                !mate_ref_str ||
                !mate_pos_str ||
                !inferred_insert_sz_str ||
                !seq_str ||
                !qual_str)
        {
                // truncated or malformed SAM record
                return false;
        }
        
        
        int sam_flag = atoi(sam_flag_str);
        int text_offset = atoi(text_offset_str);

        bool end = true;
        unsigned int seg_offset = 0;
        unsigned int seg_num = 0;
        unsigned int num_segs = 0;

        // Copy the tag out of the name field before we might wipe it out
        parseSegReadName(name, name_tags, strip_slash, end, seg_offset, seg_num, num_segs);
        
        vector<CigarOp> cigar;
        bool spliced_alignment = false;
        int refspan=parseCigar(cigar, cigar_str, spliced_alignment);
        if (refspan==0)
           return false;
        //vector<string> attributes;
        //tokenize(tag_buf, " \t",attributes);

        bool antisense_splice = false;
        int sam_nm = 0; //the value of the NM tag (edit distance)
        //int mismatches[1024];//array with mismatch positions on the read (0-based from the left aligned end of the read)
        vector<int> mismatches;
        getSAMmismatches(buf, cigar, mismatches, sam_nm, antisense_splice);
        
        if (spliced_alignment)
        {
                bh = create_hit(name,
                                text_name,
                                text_offset - 1, 
                                cigar,
                                sam_flag & 0x0010,
                                antisense_splice,
                                mismatches.size(),
                                0,
                                end);
        }
        else
        {               
                //assert(cigar.size() == 1 && cigar[0].opcode == MATCH);
                bh = create_hit(name,
                                text_name,
                                text_offset - 1, // SAM files are 1-indexed 
                                cigar,
                                sam_flag & 0x0010,
                                false,
                                mismatches.size(),
                                0,
                                end);
        }
        return true;
}

void cigar_add(vector<CigarOp>& cigar, CigarOp& op) {
 if (op.length<=0) return;
 if (cigar.size()>0 && cigar.back().opcode==op.opcode) {
    cigar.back().length+=op.length;
    }
 cigar.push_back(op);
}

int spliceCigar(vector<CigarOp>& splcigar, vector<CigarOp>& cigar, vector<int> mismatches,
                int &left, int spl_start, int spl_len, CigarOpCode spl_code) {
 //merge the original 'cigar' with the new insert/gap operation
 //at position spl_start and place the result into splcigar;
 int num_mismatches=mismatches.size();
 //these offsets are relative to the beginning of alignment on reference
 int spl_ofs=spl_start-left; //relative position of splice op
 int spl_ofs_end=spl_ofs; //relative position of first ref base AFTER splice op
 CigarOp gapop(spl_code, spl_len); //for DEL or REF_SKIP
 if (spl_code==INS)
     spl_ofs_end += spl_len;
 int ref_ofs=0; //working offset on reference
 int read_ofs=0; //working offset on the read, relative to the leftmost aligned base
 bool xfound=false;
 //if (left<=spl_start+spl_len) {
 if (spl_ofs_end>0) {
     int prev_opcode=0;
     int prev_oplen=0;
     for (size_t c = 0 ; c < cigar.size(); ++c)
      {
        int prev_read_ofs=read_ofs;
        int cur_op_ofs=ref_ofs;
        int cur_opcode=cigar[c].opcode;
        int cur_oplen=cigar[c].length;
        switch (cur_opcode) {
           case MATCH:
             ref_ofs+=cur_oplen;
             read_ofs+=cur_oplen;
             break;
           case DEL:
           case REF_SKIP:
           case PAD:
             ref_ofs+=cur_oplen;
             break;
           case SOFT_CLIP:
           case INS:
             read_ofs+=cur_oplen;
             break;
           //case HARD_CLIP:
           }
        if (cur_op_ofs>=spl_ofs_end || ref_ofs<=spl_ofs) {
           if (spl_code!=INS && cur_op_ofs==spl_ofs_end)
              {
               //we have to insert the gap here first
               cigar_add(splcigar, gapop);
              }
           cigar_add(splcigar, cigar[c]);
           }
        else //if (ref_ofs>spl_ofs) {
           { //op intersection
           xfound=true;
           if (spl_code==INS) {
                 //we have to shorten cur_opcode
                 // find the overlap between current range
                 int ovl_start = (cur_op_ofs>spl_ofs) ? cur_op_ofs : spl_ofs;
                 int ovl_end = (ref_ofs>spl_ofs_end) ? spl_ofs_end : ref_ofs;
                 CigarOp op(cigar[c]);
                 int len=op.length;
                 len-=(ovl_end-ovl_start);
                 if (len>0) {
                     op.length=len;
                     cigar_add(splcigar, op);
                     }
                 }
              else {//DEL or REF_SKIP
                 //spl_ofs == spl_ofs_end
                 //we have to split cur_opcode
                 CigarOp op(cigar[c]);
                 op.length=spl_ofs-cur_op_ofs;
                 cigar_add(splcigar, op);
                 cigar_add(splcigar, gapop);
                 op.length=ref_ofs-spl_ofs;
                 cigar_add(splcigar,op);
                 }
            } //op intersection
        prev_opcode=cur_opcode;
        prev_oplen=cur_oplen;
      } //for each cigar opcode
    } //intersection possible
  if (!xfound) {//no intersection found between splice event and alignment
   if (spl_ofs_end<=0) {
      //alignment starts after the splice event
      if (spl_code==INS) left-=spl_len;
                   else  left+=spl_len;
      }
   //else {
     //alignment ends before the splice event
     //nothing to do
    //  }
   }

 //TODO: adjust mismatches if opcode==INS and they fall in the removed part
 //TODO: what about anchor mismatches for REF_SKIP
 return num_mismatches;
}

bool SplicedSAMHitFactory::get_hit_from_buf(const char* orig_bwt_buf,
                                               BowtieHit& bh,
                                               bool strip_slash,
                                               char* name_out,
                                               char* name_tags,
                                               char* seq,
                                               char* qual)
{
        if (!orig_bwt_buf || !*orig_bwt_buf)
                return false;

        char bwt_buf[2048];
        strcpy(bwt_buf, orig_bwt_buf);
        // Are we still in the header region?
        if (bwt_buf[0] == '@')
                return false;

        char* buf = bwt_buf;
        char* name = get_token((char**)&buf,"\t");
        char* sam_flag_str = get_token((char**)&buf,"\t");
        char* text_name = get_token((char**)&buf,"\t");
        char* text_offset_str = get_token((char**)&buf,"\t");
        const char* map_qual_str = get_token((char**)&buf,"\t");
        char* cigar_str = get_token((char**)&buf,"\t");
        const char* mate_ref_str =  get_token((char**)&buf,"\t");
        const char* mate_pos_str =  get_token((char**)&buf,"\t");
        const char* inferred_insert_sz_str =  get_token((char**)&buf,"\t");
        //int num_mismatches=0;
  //int mismatches[1024]; //list of 0-based mismatch positions in this read
                          //parsed from SAM's MD:Z: tag
        const char* seq_str =  get_token((char**)&buf,"\t");
        if (seq)
          strcpy(seq, seq_str);

        const char* qual_str =  get_token((char**)&buf,"\t");
        if (qual)
          strcpy(qual, qual_str);

        if (!name ||
                !sam_flag_str ||
                !text_name ||
                !text_offset_str ||
                !map_qual_str ||
                !cigar_str ||
                !mate_ref_str ||
                !mate_pos_str ||
                !inferred_insert_sz_str ||
                !seq_str ||
                !qual_str)
        {
                // truncated or malformed SAM record
                return false;
        }


        int sam_flag = atoi(sam_flag_str);
        int text_offset = atoi(text_offset_str);
  text_offset--; //make it 0-based (SAM is 1-based, Bowtie is 0-based)
        bool end = true;
        unsigned int seg_offset = 0;
        unsigned int seg_num = 0;
        unsigned int num_segs = 0;

        // Copy the tag out of the name field before we might wipe it out
        parseSegReadName(name, name_tags, strip_slash, end, seg_offset, seg_num, num_segs);

        vector<CigarOp> samcigar;
        bool spliced_alignment = false;
        int refspan=parseCigar(samcigar, cigar_str, spliced_alignment);
  if (refspan==0)
      return false;
        bool antisense_splice = false;
        int sam_nm = 0;
  vector<int> mismatches;
  getSAMmismatches(buf, samcigar, mismatches, sam_nm, antisense_splice);

        //##############################################

        // Add this alignment to the table of hits for this half of the
        // Bowtie map

        // Parse the text_name field to recover the splice coords
        vector<string> toks;
        tokenize_strict(text_name, "|", toks);

        int num_extra_toks = (int)toks.size() - 6;

        if (num_extra_toks >= 0)
        {
                static const uint8_t left_window_edge_field = 1;
                static const uint8_t splice_field = 2;
                //static const uint8_t right_window_edge_field = 3;
                static const uint8_t junction_type_field = 4;
                static const uint8_t strand_field = 5;

                string contig = toks[0];
                for (int t = 1; t <= num_extra_toks; ++t)
                {
                        contig += "|";
                        contig += toks[t];
                }

                vector<string> splice_toks;
                tokenize(toks[num_extra_toks + splice_field], "-", splice_toks);
                if (splice_toks.size() != 2)
                {
                        fprintf(stderr, "Warning: found malformed splice record, skipping:\n");
                        //fprintf(stderr, "\t%s (token: %s)\n", text_name,
                        //        toks[num_extra_toks + splice_field].c_str());
                        return false;
                }

    string junction_strand = toks[num_extra_toks + strand_field];
    if(junction_strand != "rev" && junction_strand != "fwd"){
      fprintf(stderr, "Malformed insertion record\n");
      return false;
      }

    int spl_num_mismatches=0;

                //
                // check for an insertion hit
                //
                if(toks[num_extra_toks + junction_type_field] == "ins")
                  {
                        //int8_t spliced_read_len = strlen(seq_str);
                        //TODO FIXME: use the CIGAR instead of seq length!
                         // The 0-based position of the left edge of the alignment. Note that this
                 // value may need to be further corrected to account for the presence of
                         // of the insertion.
                        int left = atoi(toks[num_extra_toks + left_window_edge_field].c_str()) + text_offset;

                        // The 0-based position of the last genomic sequence before the insertion
                        int left_splice_pos = atoi(splice_toks[0].c_str());

                        string insertedSequence = splice_toks[1];
                        // The 0-based position of the first genomic sequence after the insertion

      vector<CigarOp> splcigar;

      //TODO: implement this
      //this also updates left to the adjusted genomic coordinates
      spl_num_mismatches=spliceCigar(splcigar, samcigar, mismatches,
                        left, left_splice_pos, insertedSequence.length(), INS);
      /*
                        uint32_t right_splice_pos = left_splice_pos + 1;

      //uint32_t right = left + spliced_read_len - 1;
      int right = left + refspan - 1;

                        if(left > left_splice_pos){
                                 //The genomic position of the left edge of the alignment needs to be corrected
                                 //If the alignment does not extend into the insertion, simply subtract the length
                                 //of the inserted sequence, otherwise, just set it equal to the right edge
                                left = left - insertedSequence.length();
                                if(left < right_splice_pos){
                                        left = right_splice_pos;
                                }
                        }
                        if(right > left_splice_pos){
                                right = right - insertedSequence.length();
                                if(right < left_splice_pos){
                                        right = left_splice_pos;
                                }
                        }
                 // Now, right and left should be properly transformed into genomic coordinates
                 // We should be able to deduce how much the alignment matches the insertion
                 // simply based on the length of the read
                        int left_match_length = 0;
                        if(left <= left_splice_pos){
                                left_match_length = left_splice_pos - left + 1;
                        }
                        int right_match_length = 0;
                        if(right >= right_splice_pos){
                                right_match_length = right - right_splice_pos + 1;
                        }
                        int insertion_match_length = spliced_read_len - left_match_length - right_match_length;

                        if(left_match_length <= 0 || right_match_length <= 0 || insertion_match_length <= 0)
                          return false;

                        //char* pch = strtok( mismatches, ",");
                        //unsigned char num_mismatches = 0;
                        //text_offset holds the left end of the alignment,
                        //RELATIVE TO the start of the contig

                        //The 0-based relative position of the left-most character
                        //before the insertion in the contig
                        int relative_splice_pos = left_splice_pos - atoi(toks[num_extra_toks + left_window_edge_field].c_str());
                        for (size_t i=0;i<mismatches.size();++i) {
                                int mismatch_pos = mismatches[i];
                                // for reversely mapped reads,
                                //find the correct mismatched position.
                                if (sam_flag & 0x0010){
                                  mismatch_pos = spliced_read_len - mismatch_pos - 1;
                                  }

                                //Only count mismatches outside of the insertion region
                                // If there is a mismatch within the insertion,
                                // disallow this hit
                                if(mismatch_pos + text_offset <= relative_splice_pos ||
                                    mismatch_pos + text_offset > relative_splice_pos + insertedSequence.length()){
                                  spl_num_mismatches++;
                                }else{
                                  return false;
                                }
                        }
      */
                        //vector<CigarOp> splcigar;
                        //spliceCigar(splcigar, samcigar, left_match_length, insertion_match_length, right_match_length, INS);
                        //splcigar.push_back(CigarOp(MATCH, left_match_length));
                        //splcigar.push_back(CigarOp(INS, insertion_match_length));
                        //splcigar.push_back(CigarOp(MATCH, right_match_length));

                        bh = create_hit(name,
                                        contig,
                                        left,
                                        //splcigar,
                                        splcigar,
                                        sam_flag & 0x0010,
                                        junction_strand == "rev",
                                        spl_num_mismatches,
                                        0,
                                        end);
                        return true;
                } //"ins"
                else //"del" or intron
                  {
                    int left = atoi(toks[num_extra_toks + left_window_edge_field].c_str()) + text_offset;
                    int spliced_read_len = strlen(seq_str); //FIXME TODO: use CIGAR instead
                    int left_splice_pos = atoi(splice_toks[0].c_str()) - left + 1;
                    if(left_splice_pos > spliced_read_len) left_splice_pos = spliced_read_len;
                    int right_splice_pos = spliced_read_len - left_splice_pos;

                    if (right_splice_pos <= 0 || left_splice_pos <= 0)
                      return false;

                    if ((sam_flag & 0x0010) == 0) //######
                      {
            if (left_splice_pos + seg_offset < _anchor_length)
              return false;
          }
        else
          {
            if (right_splice_pos + seg_offset < _anchor_length)
              return false;
          }
                    //uint32_t right = atoi(splice_toks[1].c_str()) + right_splice_pos;
                    //atoi(toks[right_window_edge_field].c_str());
                    int gap_len = atoi(splice_toks[1].c_str()) - atoi(splice_toks[0].c_str()) - 1;

                    int mismatches_in_anchor = 0;
                    for (size_t i=0;i<mismatches.size();++i) {
                                  spl_num_mismatches++;
                                  int mismatch_pos = mismatches[i];
                                  if (((sam_flag & 0x0010) == 0 && abs(mismatch_pos - left_splice_pos) < (int)min_anchor_len) ||
                                    ((sam_flag & 0x0010) != 0 &&
                                                  abs(((int)spliced_read_len - left_splice_pos + 1) - mismatch_pos)) < (int)min_anchor_len)
                                          mismatches_in_anchor++;
                                  }

                    // FIXME: we probably should exclude these hits somewhere, but this
                    // isn't the right place
                    vector<CigarOp> splcigar;
                    CigarOpCode opcode=(toks[num_extra_toks + junction_type_field] == "del")? DEL : REF_SKIP ;
                    //TODO: FIXME: use relative offsets for this call instead, like for the INS case
                    spl_num_mismatches=spliceCigar(splcigar, samcigar, mismatches, left, left_splice_pos, gap_len, opcode);
            /*
                    splcigar.push_back(CigarOp(MATCH, left_splice_pos));
                    if(toks[num_extra_toks + junction_type_field] == "del"){
                      splcigar.push_back(CigarOp(DEL, gap_len));
                    }else{
                      splcigar.push_back(CigarOp(REF_SKIP, gap_len));
                    }
                    splcigar.push_back(CigarOp(MATCH, right_splice_pos));
            */
                    bh = create_hit(name,
                                    contig,
                                    left,
                                    splcigar,
                                    (sam_flag & 0x0010),
                                    junction_strand == "rev",
                                    spl_num_mismatches,
                                    mismatches_in_anchor,
                                    end);
                    return true;
                  }
        } //parse splice data
        else
        {
          fprintf(stderr, "Warning: found malformed splice record, skipping\n");
          //fprintf(stderr, "%s\n", orig_bwt_buf);
          //                    continue;
                return false;
        }

        return false;
}


bool BAMHitFactory::get_hit_from_buf(const char* orig_bwt_buf, 
                                 BowtieHit& bh, bool strip_slash,
                                char* name_out, char* name_tags,
                                char* seq, char* qual) {
    if (_sam_header==NULL)
      err_die("Error: no SAM header when BAMHitFactory::get_hit_from_buf()!");
        const bam1_t* hit_buf = (const bam1_t*)orig_bwt_buf;


        uint32_t sam_flag = hit_buf->core.flag;
        
        int text_offset = hit_buf->core.pos;
        int text_mate_pos = hit_buf->core.mpos;
        int target_id = hit_buf->core.tid;
        int mate_target_id = hit_buf->core.mtid;
        
        vector<CigarOp> cigar;
        bool spliced_alignment = false;
        int num_hits = 1;
        
        double mapQ = hit_buf->core.qual;
        long double error_prob;
        if (mapQ > 0)
        {
                long double p = (-1.0 * mapQ) / 10.0;
                error_prob = pow(10.0L, p);
        }
        else
        {
                error_prob = 1.0;
        }

        //header->target_name[c->tid]
        
    bool end = true;
    unsigned int seg_offset = 0;
    unsigned int seg_num = 0;
    unsigned int num_segs = 0;
    // Copy the tag out of the name field before we might wipe it out
    char* qname = bam1_qname(hit_buf);
    char* pipe = strrchr(qname, '|');
    if (pipe)
    {
        if (name_tags)
            strcpy(name_tags, pipe);

        char* tag_buf = pipe + 1;
        if (strchr(tag_buf, ':'))
          {
            sscanf(tag_buf, "%u:%u:%u", &seg_offset, &seg_num, &num_segs);
            if (seg_num + 1 == num_segs)
              end = true;
            else
              end = false;
          }

        *pipe = 0;
    }


        if (target_id < 0)      {
                //assert(cigar.size() == 1 && cigar[0].opcode == MATCH);
            bh = create_hit(qname,
                        "*", //ref_name
                        0, //left coord
                        0, //read_len
                        false, //antisense_aln
                        0, //edit_dist
                        end);
                return true;
        }
        
        //string text_name = ((samfile_t*)(hs._hit_file))->header->target_name[target_id];
        string text_name = _sam_header->target_name[target_id];
        for (int i = 0; i < hit_buf->core.n_cigar; ++i) 
        {
                //char* t;

                int length = bam1_cigar(hit_buf)[i] >> BAM_CIGAR_SHIFT;
                if (length <= 0)
                {
                        fprintf (stderr, "BAM error: CIGAR op has zero length\n");
                        return false;
                }
                
                CigarOpCode opcode;
                switch(bam1_cigar(hit_buf)[i] & BAM_CIGAR_MASK)
                {
                        case BAM_CMATCH: opcode  = MATCH; break; 
                        case BAM_CINS: opcode  = INS; break;
                        case BAM_CDEL: opcode  = DEL; break; 
                        case BAM_CSOFT_CLIP: opcode  = SOFT_CLIP; break;
                        case BAM_CHARD_CLIP: opcode  = HARD_CLIP; break;
                        case BAM_CPAD: opcode  = PAD; break; 
                        case BAM_CREF_SKIP:
                                opcode = REF_SKIP;
                                spliced_alignment = true;
                                if (length > (int)max_report_intron_length)
                                {
                                        //fprintf(stderr, "Encounter REF_SKIP > max_gene_length, skipping\n");
                                        return false;
                                }
                                break;
                        default:
                                fprintf (stderr, "BAM read: invalid CIGAR operation\n");
                                return false;
                }
                if (opcode != HARD_CLIP)
                        cigar.push_back(CigarOp(opcode, length));
        }
        
        string mrnm;
        if (mate_target_id >= 0) {
                if (mate_target_id == target_id) {
                        //mrnm = ((samfile_t*)(hs._hit_file))->header->target_name[mate_target_id];
                    mrnm = _sam_header->target_name[mate_target_id];
                    }
                else {
                        //fprintf(stderr, "Trans-spliced mates are not currently supported, skipping\n");
                        return false;
                    }
           }
        else {
           text_mate_pos = 0;
           }
        //CuffStrand source_strand = CUFF_STRAND_UNKNOWN;
        bool antisense_splice=false;
        unsigned char num_mismatches = 0;
    unsigned char num_splice_anchor_mismatches = 0;

        uint8_t* ptr = bam_aux_get(hit_buf, "XS");
        if (ptr) {
                char src_strand_char = bam_aux2A(ptr);
                if (src_strand_char == '-')
                        antisense_splice = true;
                // else if (src_strand_char == '+')
                //      source_strand = CUFF_FWD;
            }

        ptr = bam_aux_get(hit_buf, "NM");
        if (ptr) {
                num_mismatches = bam_aux2i(ptr);
                }

        ptr = bam_aux_get(hit_buf, "NH");
        if (ptr) {
                num_hits = bam_aux2i(ptr);
                }
        
    //bool antisense_aln = bam1_strand(hit_buf);
    
    //if (_rg_props.strandedness() == STRANDED_PROTOCOL && source_strand == CUFF_STRAND_UNKNOWN)
        //      source_strand = use_stranded_protocol(sam_flag, antisense_aln, _rg_props.mate_strand_mapping());
        if (spliced_alignment)  {
      //if (source_strand == CUFF_STRAND_UNKNOWN) {
      //  fprintf(stderr, "BAM record error: found spliced alignment without XS attribute\n");
      //  }
      bh = create_hit(qname,
                      text_name,
                      text_offset,  // BAM files are 0-indexed
                      cigar,
                      sam_flag & 0x0010,
                      antisense_splice,
                      num_mismatches,
                      num_splice_anchor_mismatches,
                      end);

                }
        else {
      //assert(_rg_props.strandedness() == STRANDED_PROTOCOL || source_strand == CUFF_STRAND_UNKNOWN);
      //assert(cigar.size() == 1 && cigar[0].opcode == MATCH);
      bh = create_hit(qname,
                        text_name,
                        text_offset,  // BAM files are 0-indexed
                        cigar,
                        sam_flag & 0x0010,
                        false,
                        num_mismatches,
                        0,
                        end);
     }
    if (seq!=NULL) {
       char *bseq = (char*)bam1_seq(hit_buf);
       for(int i=0;i<(hit_buf->core.l_qseq);i++) {
         char v = bam1_seqi(bseq,i);
         seq[i]=bam_nt16_rev_table[v];
         }
       seq[hit_buf->core.l_qseq]=0;
       }
    if (qual!=NULL) {
       char *bq  = (char*)bam1_qual(hit_buf);
       for(int i=0;i<(hit_buf->core.l_qseq);i++) {
          qual[i]=bq[i]+33;
          }
       qual[hit_buf->core.l_qseq]=0;
       }
    return true;
}

bool BAMHitFactory::inspect_header(HitStream& hs)
{
    bam_header_t* header = ((samfile_t*)(hs._hit_file))->header;
    
    if (header == NULL) {
       fprintf(stderr, "Warning: No BAM header\n");
       return false;
       }
    if (header->l_text == 0) {
      fprintf(stderr, "Warning: BAM header has 0 length or is corrupted.  Try using 'samtools reheader'.\n");
      return false;
      }
    return true;
}


void get_mapped_reads(FILE* bwtf, 
                                          HitTable& hits, 
                                          HitFactory& hit_factory,
                                          bool strip_slash,
                                          bool verbose)
{

        
    char bwt_buf[2048];
        uint32_t reads_extracted = 0;
        
        while (fgets(bwt_buf, 2048, bwtf))
        {
                // Chomp the newline
                char* nl = strrchr(bwt_buf, '\n');
                if (nl) *nl = 0;
                if (*bwt_buf == 0)
                        continue;
                // Get a new record from the tab-delimited Bowtie map
                BowtieHit bh;
                if (hit_factory.get_hit_from_buf(bwt_buf, bh, strip_slash))
                {
                        // Only check uniqueness if these hits are spliced
                        hits.add_hit(bh, true);
                }
                reads_extracted++;
        }
        
        // This will sort the map by insert id.
        hits.finalize();
        fprintf(stderr, "Extracted %d alignments from Bowtie map\n", reads_extracted);
}


/*
AlignStatus status(const BowtieHit* align)
{
        if (!align)
                return UNALIGNED;
        if (align->contiguous())
                return CONTIGUOUS;
        return SPLICED;
}
*/

void add_hits_to_coverage(const HitList& hits, vector<unsigned short>& DoC)
{
        int max_hit_pos = -1;
        for (size_t i = 0; i < hits.size(); ++i)
        {
                max_hit_pos = max((int)hits[i].right(),max_hit_pos);
        }
        
        if ((int)DoC.size() < max_hit_pos)
                DoC.resize(max_hit_pos);
        
        for (size_t i = 0; i < hits.size(); ++i)
        {
                const BowtieHit& bh = hits[i];
                
                // split up the coverage contibution for this reads
                size_t j = bh.left();
                const vector<CigarOp>& cigar = bh.cigar();

                for (size_t c = 0 ; c < cigar.size(); ++c)
                {
                        switch(cigar[c].opcode)
                        {
                                case MATCH:
                                        for (size_t m = 0; m < cigar[c].length; ++m)
                                        {
                                                if (DoC[j + m] < 0xFFFF)
                                                        DoC[j + m]++;
                                        }
                                //fall through this case to REF_SKIP is intentional
                                case REF_SKIP:
                                        j += cigar[c].length;
                                        break;
                                default:
                                        break;
                        }
                         
                }
        }
}

void add_hit_to_coverage(const BowtieHit& bh, vector<unsigned int>& DoC)
{
        if ((int)DoC.size() < bh.right())
                DoC.resize(bh.right());
                        
        // split up the coverage contibution for this reads
        size_t j = bh.left();
        const vector<CigarOp>& cigar = bh.cigar();
        
        for (size_t c = 0 ; c < cigar.size(); ++c)
        {
                switch(cigar[c].opcode)
                {
                        case MATCH:
                                for (size_t m = 0; m < cigar[c].length; ++m)
                                {
                                        if (DoC[j + m] < VMAXINT32)
                                                DoC[j + m]++;
                                }
                                //fall through this case to REF_SKIP is intentional
                        case REF_SKIP:
                                j += cigar[c].length;
                                break;
                        default:
                                break;
                }
                
        }
}

void print_hit(FILE* fout, 
               const char* read_name,
               const BowtieHit& bh,
               const char* ref_name,
               const char* sequence,
               const char* qualities,
               bool from_bowtie)
{
        string seq;
        string quals;
        if (sequence)
        {
                seq = sequence;
                quals = qualities;
                seq.resize(bh.read_len());
                quals.resize(bh.read_len());
        }
        else
        {
                seq = "*";
        }
        
        if (qualities)
        {
                quals = qualities;
                quals.resize(bh.read_len());
        }
        else
        {
                quals = "*";    
        }

        uint32_t sam_flag = 0;
        if (bh.antisense_align())
        {
                sam_flag |= 0x0010; // BAM_FREVERSE
                if (sequence && !from_bowtie)  // if it is from bowtie hit, it's already reversed.
                  {
                    reverse_complement(seq);
                    reverse(quals.begin(), quals.end());
                  }
        }
        
        uint32_t sam_pos = bh.left() + 1;
        uint32_t map_quality = 255;
        char cigar[256];
        cigar[0] = 0;
        string mate_ref_name = "*";
        uint32_t mate_pos = 0;
        uint32_t insert_size = 0;
        //string qualities = "*";
        
        const vector<CigarOp>& bh_cigar = bh.cigar();

        /*
         * In addition to calculating the cigar string,
         * we need to figure out how many in/dels are in the 
         * sequence, so that we can give the correct
         * value for the NM tag
         */
        int indel_distance = 0;
        for (size_t c = 0; c < bh_cigar.size(); ++c)
        {
                char ibuf[64];
                sprintf(ibuf, "%d", bh_cigar[c].length);
                switch(bh_cigar[c].opcode)
                {
                        case MATCH:
                                strcat(cigar, ibuf);
                                strcat(cigar, "M");
                                break;
                        case INS:
                                strcat(cigar, ibuf);
                                strcat(cigar, "I");
                                indel_distance += bh_cigar[c].length;
                                break;
                        case DEL:
                                strcat(cigar, ibuf);
                                strcat(cigar, "D");
                                indel_distance += bh_cigar[c].length;
                                break;
                        case REF_SKIP:
                                strcat(cigar, ibuf);
                                strcat(cigar, "N");
                                break;
                        default:
                                break;
                }
        }
        
        //string q = string(bh.read_len(), '!');
        //string s = string(bh.read_len(), 'N');
        
        fprintf(fout,
                        "%s\t%d\t%s\t%d\t%d\t%s\t%s\t%d\t%d\t%s\t%s",
                        read_name,
                        sam_flag,
                        ref_name,
                        sam_pos,
                        map_quality,
                        cigar,
                        mate_ref_name.c_str(),
                        mate_pos,
                        insert_size,
                        seq.c_str(),
                        quals.c_str());
        
    if (!sam_readgroup_id.empty())
        fprintf(fout, "\tRG:Z:%s", sam_readgroup_id.c_str());
    
        fprintf(fout, "\tNM:i:%d", bh.edit_dist() + indel_distance);

        bool containsSplice = false;
        for(vector<CigarOp>::const_iterator itr = bh.cigar().begin(); itr != bh.cigar().end(); ++itr){
                if(itr->opcode == REF_SKIP){
                        containsSplice = true;
                        break;
                }
        }

        if (containsSplice)
          fprintf(fout, "\tXS:A:%c", bh.antisense_splice() ? '-' : '+');

        fprintf(fout, "\n");
}

void print_bamhit(GBamWriter& wbam,
           const char* read_name,
           const BowtieHit& bh,
           const char* ref_name,
           const char* sequence,
           const char* qualities,
           bool from_bowtie)
{
    string seq;
    string quals;
    if (sequence) {
        seq = sequence;
        quals = qualities;
        seq.resize(bh.read_len());
        quals.resize(bh.read_len());
        }
      else {
        seq = "*";
        }
    if (qualities) {
        quals = qualities;
        quals.resize(bh.read_len());
    }
    else
    {
        quals = "*";
    }

    uint32_t sam_flag = 0;
    if (bh.antisense_align())
    {
        sam_flag |= 0x0010; // BAM_FREVERSE
        if (sequence && !from_bowtie)  // if it is from bowtie hit, it's already reversed.
          {
            reverse_complement(seq);
            reverse(quals.begin(), quals.end());
          }
    }

    uint32_t sam_pos = bh.left() + 1;
    uint32_t map_quality = 255;
    char cigar[256];
    cigar[0] = 0;
    string mate_ref_name = "*";
    uint32_t mate_pos = 0;
    uint32_t insert_size = 0;
    //string qualities = "*";

    const vector<CigarOp>& bh_cigar = bh.cigar();
    /*
     * In addition to calculating the cigar string,
     * we need to figure out how many in/dels are in the
     * sequence, so that we can give the correct
     * value for the NM tag
     */
    int indel_distance = 0;
    for (size_t c = 0; c < bh_cigar.size(); ++c)
    {
        char ibuf[64];
        sprintf(ibuf, "%d", bh_cigar[c].length);
        switch(bh_cigar[c].opcode)
        {
            case MATCH:
                strcat(cigar, ibuf);
                strcat(cigar, "M");
                break;
            case INS:
                strcat(cigar, ibuf);
                strcat(cigar, "I");
                indel_distance += bh_cigar[c].length;
                break;
            case DEL:
                strcat(cigar, ibuf);
                strcat(cigar, "D");
                indel_distance += bh_cigar[c].length;
                break;
            case REF_SKIP:
                strcat(cigar, ibuf);
                strcat(cigar, "N");
                break;
            default:
                break;
        }
    }

    //string q = string(bh.read_len(), '!');
    //string s = string(bh.read_len(), 'N');
    /*
    fprintf(fout,
            "%s\t%d\t%s\t%d\t%d\t%s\t%s\t%d\t%d\t%s\t%s",
            read_name,
            sam_flag,
            ref_name,
            sam_pos,
            map_quality,
            cigar,
            mate_ref_name.c_str(),
            mate_pos,
            insert_size,
            seq.c_str(),
            quals.c_str());

    fprintf(fout, "\tNM:i:%d", bh.edit_dist() + indel_distance);
    */
    vector<string> auxdata;
    
    if (!sam_readgroup_id.empty())
    {
        string nm("RG:Z:");
        nm += sam_readgroup_id;
        auxdata.push_back(nm);
    }
    
    string nm("NM:i:");
    str_appendInt(nm, bh.edit_dist() + indel_distance);
    auxdata.push_back(nm);
    bool containsSplice = false;
    for(vector<CigarOp>::const_iterator itr = bh.cigar().begin(); itr != bh.cigar().end(); ++itr)
       if(itr->opcode == REF_SKIP){
            containsSplice = true;
            break;
            }

    if (containsSplice) {
       //fprintf(fout, "\tXS:A:%c", bh.antisense_splice() ? '-' : '+');
       nm="XS:A:";
       nm+=(char)(bh.antisense_splice() ? '-' : '+');
       auxdata.push_back(nm);
       }

    GBamRecord *brec = wbam.new_record(read_name, sam_flag, ref_name, sam_pos, map_quality,
                        cigar, mate_ref_name.c_str(), mate_pos,
                        insert_size, seq.c_str(), quals.c_str(), &auxdata);
                        
    
    wbam.write(brec);
    delete brec;
}

/**
 * Print a vector of cigar operations to a file.
 * @param bh_cigar A vector of CigarOps
 * @return a string representation of the cigar string
*/
std::string print_cigar(vector<CigarOp>& bh_cigar){
        char cigar[256];
        cigar[0] = 0;   
        for (size_t c = 0; c < bh_cigar.size(); ++c)
        {
                char ibuf[64];
                sprintf(ibuf, "%d", bh_cigar[c].length);
                switch(bh_cigar[c].opcode)
                {
                        case MATCH:
                                strcat(cigar, ibuf);
                                strcat(cigar, "M");
                                break;
                        case INS:
                                strcat(cigar, ibuf);
                                strcat(cigar, "I");
                                break;
                        case DEL:
                                strcat(cigar, ibuf);
                                strcat(cigar, "D");
                                break;
                        case REF_SKIP:
                                strcat(cigar, ibuf);
                                strcat(cigar, "N");
                                break;
                        default:
                                break;
                }
        }
        string result(cigar);
        return result;
}

bool BowtieHit::check_editdist_consistency(const RefSequenceTable& rt)
{
  RefSequenceTable::Sequence* ref_str = rt.get_seq(_ref_id);
  if (!ref_str)
    return false;
  
  const seqan::Dna5String ref_seq = seqan::infix(*ref_str, _left, right());

  size_t pos_seq = 0;
  size_t pos_ref = 0;
  size_t mismatch = 0;
  for (size_t i = 0; i < _cigar.size(); ++i)
    {
      CigarOp cigar = _cigar[i];
      switch(cigar.opcode)
        {
        case MATCH:
          {
            for (size_t j = 0; j < cigar.length; ++j)
              {
                if (_seq[pos_seq++] != ref_seq[pos_ref++])
                  ++mismatch;
              }
          }
          break;
        case INS:
          {
            pos_seq += cigar.length;
          }
          break;
          
        case DEL:
        case REF_SKIP:
          {
            pos_ref += cigar.length;
          }
          break;

        default:
          break;
        }
    }
  
  return mismatch == _edit_dist;
}
Revision:	137
Committed:	Wed Dec 14 22:58:22 2011 UTC (9 years, 1 month ago) by gpertea
File size:	56203 byte(s)
Log Message:	wip spliceCigar() in bwt_map.cpp needs testing