Imported Upstream version 0.1.10
[samtools.git] / bam2bcf_indel.c
diff --git a/bam2bcf_indel.c b/bam2bcf_indel.c
new file mode 100644 (file)
index 0000000..819c1e7
--- /dev/null
@@ -0,0 +1,410 @@
+#include <assert.h>
+#include <ctype.h>
+#include <string.h>
+#include "bam.h"
+#include "bam2bcf.h"
+#include "ksort.h"
+#include "kaln.h"
+#include "kprobaln.h"
+#include "khash.h"
+KHASH_SET_INIT_STR(rg)
+
+#define MINUS_CONST 0x10000000
+#define INDEL_WINDOW_SIZE 50
+#define MIN_SUPPORT_COEF 500
+
+void *bcf_call_add_rg(void *_hash, const char *hdtext, const char *list)
+{
+       const char *s, *p, *q, *r, *t;
+       khash_t(rg) *hash;
+       if (list == 0 || hdtext == 0) return _hash;
+       if (_hash == 0) _hash = kh_init(rg);
+       hash = (khash_t(rg)*)_hash;
+       if ((s = strstr(hdtext, "@RG\t")) == 0) return hash;
+       do {
+               t = strstr(s + 4, "@RG\t"); // the next @RG
+               if ((p = strstr(s, "\tID:")) != 0) p += 4;
+               if ((q = strstr(s, "\tPL:")) != 0) q += 4;
+               if (p && q && (t == 0 || (p < t && q < t))) { // ID and PL are both present
+                       int lp, lq;
+                       char *x;
+                       for (r = p; *r && *r != '\t' && *r != '\n'; ++r); lp = r - p;
+                       for (r = q; *r && *r != '\t' && *r != '\n'; ++r); lq = r - q;
+                       x = calloc((lp > lq? lp : lq) + 1, 1);
+                       for (r = q; *r && *r != '\t' && *r != '\n'; ++r) x[r-q] = *r;
+                       if (strstr(list, x)) { // insert ID to the hash table
+                               khint_t k;
+                               int ret;
+                               for (r = p; *r && *r != '\t' && *r != '\n'; ++r) x[r-p] = *r;
+                               x[r-p] = 0;
+                               k = kh_get(rg, hash, x);
+                               if (k == kh_end(hash)) k = kh_put(rg, hash, x, &ret);
+                               else free(x);
+                       } else free(x);
+               }
+               s = t;
+       } while (s);
+       return hash;
+}
+
+void bcf_call_del_rghash(void *_hash)
+{
+       khint_t k;
+       khash_t(rg) *hash = (khash_t(rg)*)_hash;
+       if (hash == 0) return;
+       for (k = kh_begin(hash); k < kh_end(hash); ++k)
+               if (kh_exist(hash, k))
+                       free((char*)kh_key(hash, k));
+       kh_destroy(rg, hash);
+}
+
+static int tpos2qpos(const bam1_core_t *c, const uint32_t *cigar, int32_t tpos, int is_left, int32_t *_tpos)
+{
+       int k, x = c->pos, y = 0, last_y = 0;
+       *_tpos = c->pos;
+       for (k = 0; k < c->n_cigar; ++k) {
+               int op = cigar[k] & BAM_CIGAR_MASK;
+               int l = cigar[k] >> BAM_CIGAR_SHIFT;
+               if (op == BAM_CMATCH) {
+                       if (c->pos > tpos) return y;
+                       if (x + l > tpos) {
+                               *_tpos = tpos;
+                               return y + (tpos - x);
+                       }
+                       x += l; y += l;
+                       last_y = y;
+               } else if (op == BAM_CINS || op == BAM_CSOFT_CLIP) y += l;
+               else if (op == BAM_CDEL || op == BAM_CREF_SKIP) {
+                       if (x + l > tpos) {
+                               *_tpos = is_left? x : x + l;
+                               return y;
+                       }
+                       x += l;
+               }
+       }
+       *_tpos = x;
+       return last_y;
+}
+// FIXME: check if the inserted sequence is consistent with the homopolymer run
+// l is the relative gap length and l_run is the length of the homopolymer on the reference
+static inline int est_seqQ(const bcf_callaux_t *bca, int l, int l_run)
+{
+       int q, qh;
+       q = bca->openQ + bca->extQ * (abs(l) - 1);
+       qh = l_run >= 3? (int)(bca->tandemQ * (double)abs(l) / l_run + .499) : 1000;
+       return q < qh? q : qh;
+}
+
+static inline int est_indelreg(int pos, const char *ref, int l, char *ins4)
+{
+       int i, j, max = 0, max_i = pos, score = 0;
+       l = abs(l);
+       for (i = pos + 1, j = 0; ref[i]; ++i, ++j) {
+               if (ins4) score += (toupper(ref[i]) != "ACGTN"[(int)ins4[j%l]])? -10 : 1;
+               else score += (toupper(ref[i]) != toupper(ref[pos+1+j%l]))? -10 : 1;
+               if (score < 0) break;
+               if (max < score) max = score, max_i = i;
+       }
+       return max_i - pos;
+}
+
+int bcf_call_gap_prep(int n, int *n_plp, bam_pileup1_t **plp, int pos, bcf_callaux_t *bca, const char *ref,
+                                         const void *rghash)
+{
+       extern void ks_introsort_uint32_t(int, uint32_t*);
+       int i, s, j, k, t, n_types, *types, max_rd_len, left, right, max_ins, *score1, *score2;
+       int N, K, l_run, ref_type, n_alt;
+       char *inscns = 0, *ref2, *query;
+       khash_t(rg) *hash = (khash_t(rg)*)rghash;
+       if (ref == 0 || bca == 0) return -1;
+       // mark filtered reads
+       if (rghash) {
+               N = 0;
+               for (s = N = 0; s < n; ++s) {
+                       for (i = 0; i < n_plp[s]; ++i) {
+                               bam_pileup1_t *p = plp[s] + i;
+                               const uint8_t *rg = bam_aux_get(p->b, "RG");
+                               p->aux = 1; // filtered by default
+                               if (rg) {
+                                       khint_t k = kh_get(rg, hash, (const char*)(rg + 1));
+                                       if (k != kh_end(hash)) p->aux = 0, ++N; // not filtered
+                               }
+                       }
+               }
+               if (N == 0) return -1; // no reads left
+       }
+       // determine if there is a gap
+       for (s = N = 0; s < n; ++s) {
+               for (i = 0; i < n_plp[s]; ++i)
+                       if (plp[s][i].indel != 0) break;
+               if (i < n_plp[s]) break;
+       }
+       if (s == n) return -1; // there is no indel at this position.
+       for (s = N = 0; s < n; ++s) N += n_plp[s]; // N is the total number of reads
+       { // find out how many types of indels are present
+               int m, n_alt = 0, n_tot = 0;
+               uint32_t *aux;
+               aux = calloc(N + 1, 4);
+               m = max_rd_len = 0;
+               aux[m++] = MINUS_CONST; // zero indel is always a type
+               for (s = 0; s < n; ++s) {
+                       for (i = 0; i < n_plp[s]; ++i) {
+                               const bam_pileup1_t *p = plp[s] + i;
+                               if (rghash == 0 || p->aux == 0) {
+                                       ++n_tot;
+                                       if (p->indel != 0) {
+                                               ++n_alt;
+                                               aux[m++] = MINUS_CONST + p->indel;
+                                       }
+                               }
+                               j = bam_cigar2qlen(&p->b->core, bam1_cigar(p->b));
+                               if (j > max_rd_len) max_rd_len = j;
+                       }
+               }
+               ks_introsort(uint32_t, m, aux);
+               // squeeze out identical types
+               for (i = 1, n_types = 1; i < m; ++i)
+                       if (aux[i] != aux[i-1]) ++n_types;
+               if (n_types == 1 || n_alt * MIN_SUPPORT_COEF < n_tot) { // no indels or too few supporting reads
+                       free(aux); return -1;
+               }
+               types = (int*)calloc(n_types, sizeof(int));
+               t = 0;
+               types[t++] = aux[0] - MINUS_CONST; 
+               for (i = 1; i < m; ++i)
+                       if (aux[i] != aux[i-1])
+                               types[t++] = aux[i] - MINUS_CONST;
+               free(aux);
+               for (t = 0; t < n_types; ++t)
+                       if (types[t] == 0) break;
+               ref_type = t; // the index of the reference type (0)
+               assert(n_types < 64);
+       }
+       { // calculate left and right boundary
+               left = pos > INDEL_WINDOW_SIZE? pos - INDEL_WINDOW_SIZE : 0;
+               right = pos + INDEL_WINDOW_SIZE;
+               if (types[0] < 0) right -= types[0];
+               // in case the alignments stand out the reference
+               for (i = pos; i < right; ++i)
+                       if (ref[i] == 0) break;
+               right = i;
+       }
+       { // the length of the homopolymer run around the current position
+               int c = bam_nt16_table[(int)ref[pos + 1]];
+               if (c == 15) l_run = 1;
+               else {
+                       for (i = pos + 2; ref[i]; ++i)
+                               if (bam_nt16_table[(int)ref[i]] != c) break;
+                       l_run = i;
+                       for (i = pos; i >= 0; --i)
+                               if (bam_nt16_table[(int)ref[i]] != c) break;
+                       l_run -= i + 1;
+               }
+       }
+       // construct the consensus sequence
+       max_ins = types[n_types - 1]; // max_ins is at least 0
+       if (max_ins > 0) {
+               int *inscns_aux = calloc(4 * n_types * max_ins, sizeof(int));
+               // count the number of occurrences of each base at each position for each type of insertion
+               for (t = 0; t < n_types; ++t) {
+                       if (types[t] > 0) {
+                               for (s = 0; s < n; ++s) {
+                                       for (i = 0; i < n_plp[s]; ++i) {
+                                               bam_pileup1_t *p = plp[s] + i;
+                                               if (p->indel == types[t]) {
+                                                       uint8_t *seq = bam1_seq(p->b);
+                                                       for (k = 1; k <= p->indel; ++k) {
+                                                               int c = bam_nt16_nt4_table[bam1_seqi(seq, p->qpos + k)];
+                                                               if (c < 4) ++inscns_aux[(t*max_ins+(k-1))*4 + c];
+                                                       }
+                                               }
+                                       }
+                               }
+                       }
+               }
+               // use the majority rule to construct the consensus
+               inscns = calloc(n_types * max_ins, 1);
+               for (t = 0; t < n_types; ++t) {
+                       for (j = 0; j < types[t]; ++j) {
+                               int max = 0, max_k = -1, *ia = &inscns_aux[(t*max_ins+j)*4];
+                               for (k = 0; k < 4; ++k)
+                                       if (ia[k] > max)
+                                               max = ia[k], max_k = k;
+                               inscns[t*max_ins + j] = max? max_k : 4;
+                       }
+               }
+               free(inscns_aux);
+       }
+       // compute the likelihood given each type of indel for each read
+       ref2  = calloc(right - left + max_ins + 2, 1);
+       query = calloc(right - left + max_rd_len + max_ins + 2, 1);
+       score1 = calloc(N * n_types, sizeof(int));
+       score2 = calloc(N * n_types, sizeof(int));
+       bca->indelreg = 0;
+       for (t = 0; t < n_types; ++t) {
+               int l, ir;
+               kpa_par_t apf1 = { 1e-4, 1e-2, 10 }, apf2 = { 1e-6, 1e-3, 10 };
+               apf1.bw = apf2.bw = abs(types[t]) + 3;
+               // compute indelreg
+               if (types[t] == 0) ir = 0;
+               else if (types[t] > 0) ir = est_indelreg(pos, ref, types[t], &inscns[t*max_ins]);
+               else ir = est_indelreg(pos, ref, -types[t], 0);
+               if (ir > bca->indelreg) bca->indelreg = ir;
+//             fprintf(stderr, "%d, %d, %d\n", pos, types[t], ir);
+               // write ref2
+               for (k = 0, j = left; j <= pos; ++j)
+                       ref2[k++] = bam_nt16_nt4_table[bam_nt16_table[(int)ref[j]]];
+               if (types[t] <= 0) j += -types[t];
+               else for (l = 0; l < types[t]; ++l)
+                                ref2[k++] = inscns[t*max_ins + l];
+               if (types[0] < 0) { // mask deleted sequences to avoid a particular error in the model.
+                       int jj, tmp = types[t] >= 0? -types[0] : -types[0] + types[t];
+                       for (jj = 0; jj < tmp && j < right && ref[j]; ++jj, ++j)
+                               ref2[k++] = 4;
+               }
+               for (; j < right && ref[j]; ++j)
+                       ref2[k++] = bam_nt16_nt4_table[bam_nt16_table[(int)ref[j]]];
+               if (j < right) right = j;
+               // align each read to ref2
+               for (s = K = 0; s < n; ++s) {
+                       for (i = 0; i < n_plp[s]; ++i, ++K) {
+                               bam_pileup1_t *p = plp[s] + i;
+                               int qbeg, qend, tbeg, tend, sc;
+                               uint8_t *seq = bam1_seq(p->b);
+                               // FIXME: the following skips soft clips, but using them may be more sensitive.
+                               // determine the start and end of sequences for alignment
+                               qbeg = tpos2qpos(&p->b->core, bam1_cigar(p->b), left,  0, &tbeg);
+                               qend = tpos2qpos(&p->b->core, bam1_cigar(p->b), right, 1, &tend);
+                               if (types[t] < 0) {
+                                       int l = -types[t];
+                                       tbeg = tbeg - l > left?  tbeg - l : left;
+                               }
+                               // write the query sequence
+                               for (l = qbeg; l < qend; ++l)
+                                       query[l - qbeg] = bam_nt16_nt4_table[bam1_seqi(seq, l)];
+                               { // do realignment; this is the bottleneck
+                                       const uint8_t *qual = bam1_qual(p->b), *bq;
+                                       uint8_t *qq;
+                                       qq = calloc(qend - qbeg, 1);
+                                       bq = (uint8_t*)bam_aux_get(p->b, "ZQ");
+                                       if (bq) ++bq; // skip type
+                                       for (l = qbeg; l < qend; ++l) {
+                                               qq[l - qbeg] = bq? qual[l] + (bq[l] - 64) : qual[l];
+                                               if (qq[l - qbeg] > 30) qq[l - qbeg] = 30;
+                                               if (qq[l - qbeg] < 7) qq[l - qbeg] = 7;
+                                       }
+                                       sc = kpa_glocal((uint8_t*)ref2 + tbeg - left, tend - tbeg + abs(types[t]),
+                                                                       (uint8_t*)query, qend - qbeg, qq, &apf1, 0, 0);
+                                       l = (int)(100. * sc / (qend - qbeg) + .499); // used for adjusting indelQ below
+                                       if (l > 255) l = 255;
+                                       score1[K*n_types + t] = score2[K*n_types + t] = sc<<8 | l;
+                                       if (sc > 5) {
+                                               sc = kpa_glocal((uint8_t*)ref2 + tbeg - left, tend - tbeg + abs(types[t]),
+                                                                               (uint8_t*)query, qend - qbeg, qq, &apf2, 0, 0);
+                                               l = (int)(100. * sc / (qend - qbeg) + .499);
+                                               if (l > 255) l = 255;
+                                               score2[K*n_types + t] = sc<<8 | l;
+                                       }
+                                       free(qq);
+                               }
+/*
+                               for (l = 0; l < tend - tbeg + abs(types[t]); ++l)
+                                       fputc("ACGTN"[(int)ref2[tbeg-left+l]], stderr);
+                               fputc('\n', stderr);
+                               for (l = 0; l < qend - qbeg; ++l) fputc("ACGTN"[(int)query[l]], stderr);
+                               fputc('\n', stderr);
+                               fprintf(stderr, "pos=%d type=%d read=%d:%d name=%s qbeg=%d tbeg=%d score=%d\n", pos, types[t], s, i, bam1_qname(p->b), qbeg, tbeg, sc);
+*/
+                       }
+               }
+       }
+       free(ref2); free(query);
+       { // compute indelQ
+               int *sc, tmp, *sumq;
+               sc   = alloca(n_types * sizeof(int));
+               sumq = alloca(n_types * sizeof(int));
+               memset(sumq, 0, sizeof(int) * n_types);
+               for (s = K = 0; s < n; ++s) {
+                       for (i = 0; i < n_plp[s]; ++i, ++K) {
+                               bam_pileup1_t *p = plp[s] + i;
+                               int *sct = &score1[K*n_types], indelQ1, indelQ2, seqQ, indelQ;
+                               for (t = 0; t < n_types; ++t) sc[t] = sct[t]<<6 | t;
+                               for (t = 1; t < n_types; ++t) // insertion sort
+                                       for (j = t; j > 0 && sc[j] < sc[j-1]; --j)
+                                               tmp = sc[j], sc[j] = sc[j-1], sc[j-1] = tmp;
+                               /* errmod_cal() assumes that if the call is wrong, the
+                                * likelihoods of other events are equal. This is about
+                                * right for substitutions, but is not desired for
+                                * indels. To reuse errmod_cal(), I have to make
+                                * compromise for multi-allelic indels.
+                                */
+                               if ((sc[0]&0x3f) == ref_type) {
+                                       indelQ1 = (sc[1]>>14) - (sc[0]>>14);
+                                       seqQ = est_seqQ(bca, types[sc[1]&0x3f], l_run);
+                               } else {
+                                       for (t = 0; t < n_types; ++t) // look for the reference type
+                                               if ((sc[t]&0x3f) == ref_type) break;
+                                       indelQ1 = (sc[t]>>14) - (sc[0]>>14);
+                                       seqQ = est_seqQ(bca, types[sc[0]&0x3f], l_run);
+                               }
+                               tmp = sc[0]>>6 & 0xff;
+                               indelQ1 = tmp > 111? 0 : (int)((1. - tmp/111.) * indelQ1 + .499); // reduce indelQ
+                               sct = &score2[K*n_types];
+                               for (t = 0; t < n_types; ++t) sc[t] = sct[t]<<6 | t;
+                               for (t = 1; t < n_types; ++t) // insertion sort
+                                       for (j = t; j > 0 && sc[j] < sc[j-1]; --j)
+                                               tmp = sc[j], sc[j] = sc[j-1], sc[j-1] = tmp;
+                               if ((sc[0]&0x3f) == ref_type) {
+                                       indelQ2 = (sc[1]>>14) - (sc[0]>>14);
+                               } else {
+                                       for (t = 0; t < n_types; ++t) // look for the reference type
+                                               if ((sc[t]&0x3f) == ref_type) break;
+                                       indelQ2 = (sc[t]>>14) - (sc[0]>>14);
+                               }
+                               tmp = sc[0]>>6 & 0xff;
+                               indelQ2 = tmp > 111? 0 : (int)((1. - tmp/111.) * indelQ2 + .499);
+                               // pick the smaller between indelQ1 and indelQ2
+                               indelQ = indelQ1 < indelQ2? indelQ1 : indelQ2;
+                               p->aux = (sc[0]&0x3f)<<16 | seqQ<<8 | indelQ;
+                               sumq[sc[0]&0x3f] += indelQ < seqQ? indelQ : seqQ;
+//                             fprintf(stderr, "pos=%d read=%d:%d name=%s call=%d q=%d\n", pos, s, i, bam1_qname(p->b), types[sc[0]&0x3f], indelQ);
+                       }
+               }
+               // determine bca->indel_types[] and bca->inscns
+               bca->maxins = max_ins;
+               bca->inscns = realloc(bca->inscns, bca->maxins * 4);
+               for (t = 0; t < n_types; ++t)
+                       sumq[t] = sumq[t]<<6 | t;
+               for (t = 1; t < n_types; ++t) // insertion sort
+                       for (j = t; j > 0 && sumq[j] > sumq[j-1]; --j)
+                               tmp = sumq[j], sumq[j] = sumq[j-1], sumq[j-1] = tmp;
+               for (t = 0; t < n_types; ++t) // look for the reference type
+                       if ((sumq[t]&0x3f) == ref_type) break;
+               if (t) { // then move the reference type to the first
+                       tmp = sumq[t];
+                       for (; t > 0; --t) sumq[t] = sumq[t-1];
+                       sumq[0] = tmp;
+               }
+               for (t = 0; t < 4; ++t) bca->indel_types[t] = B2B_INDEL_NULL;
+               for (t = 0; t < 4 && t < n_types; ++t) {
+                       bca->indel_types[t] = types[sumq[t]&0x3f];
+                       memcpy(&bca->inscns[t * bca->maxins], &inscns[(sumq[t]&0x3f) * max_ins], bca->maxins);
+               }
+               // update p->aux
+               for (s = n_alt = 0; s < n; ++s) {
+                       for (i = 0; i < n_plp[s]; ++i) {
+                               bam_pileup1_t *p = plp[s] + i;
+                               int x = types[p->aux>>16&0x3f];
+                               for (j = 0; j < 4; ++j)
+                                       if (x == bca->indel_types[j]) break;
+                               p->aux = j<<16 | (j == 4? 0 : (p->aux&0xffff));
+                               if ((p->aux>>16&0x3f) > 0) ++n_alt;
+//                             fprintf(stderr, "X pos=%d read=%d:%d name=%s call=%d type=%d q=%d seqQ=%d\n", pos, s, i, bam1_qname(p->b), p->aux>>16&63, bca->indel_types[p->aux>>16&63], p->aux&0xff, p->aux>>8&0xff);
+                       }
+               }               
+       }
+       free(score1); free(score2);
+       // free
+       free(types); free(inscns);
+       return n_alt > 0? 0 : -1;
+}