// Traverse from node0 -> node1
static void traverse_5pflank(BreakpointCaller *caller, GraphCrawler *crawler,
dBNode node0, dBNode node1)
{
const dBGraph *db_graph = crawler->cache.db_graph;
dBNode next_nodes[4];
Nucleotide next_nucs[4];
size_t i, num_next;
BinaryKmer bkmer0 = db_node_get_bkmer(db_graph, node0.key);
num_next = db_graph_next_nodes(db_graph, bkmer0, node0.orient,
db_node_edges(db_graph, node0.key, 0),
next_nodes, next_nucs);
// Find index of previous node
for(i = 0; i < num_next && !db_nodes_are_equal(next_nodes[i],node1); i++) {}
ctx_assert(i < num_next && db_nodes_are_equal(next_nodes[i],node1));
kmer_run_buf_reset(&caller->koruns_5p);
kmer_run_buf_reset(&caller->koruns_5p_ended);
kmer_run_buf_reset(&caller->flank5p_run_buf);
// Go backwards to get 5p flank
// NULL means loop from 0..(ncols-1)
graph_crawler_fetch(crawler, node0,
next_nodes, next_nucs, i, num_next,
NULL, db_graph->num_of_cols,
gcrawler_flank5p_stop_at_ref_covg,
gcrawler_flank5p_finish_ref_covg,
caller);
}
void test_graph_crawler()
{
test_status("Testing graph crawler...");
// Construct 1 colour graph with kmer-size=11
dBGraph graph;
const size_t kmer_size = 11, ncols = 3;
db_graph_alloc(&graph, kmer_size, ncols, 1, 2048,
DBG_ALLOC_EDGES | DBG_ALLOC_NODE_IN_COL | DBG_ALLOC_BKTLOCKS);
char graphseq[3][77] =
// < X X X...............
{"GTTCCAGAGCGGAGGTCTCCCAACAACATGGTATAAGTTGTCTAGCCCCGGTTCGCGCGGGTACTTCTTACAGCGC",
"GTTCCAGAGCGGAGGTCTCCCAACAACTTGGTATAAGTTGTCTAGTCCCGGTTCGCGCGGCATTTCAGCATTGTTA",
"GTTCCAGAGCGCGACAGAGTGCATATCACGCTAAGCACAGCCCTCTTCTATCTGCTTTTAAATGGATCAATAATCG"};
build_graph_from_str_mt(&graph, 0, graphseq[0], strlen(graphseq[0]));
build_graph_from_str_mt(&graph, 1, graphseq[1], strlen(graphseq[1]));
build_graph_from_str_mt(&graph, 2, graphseq[2], strlen(graphseq[2]));
// Crawl graph
GraphCrawler crawler;
graph_crawler_alloc(&crawler, &graph);
dBNode node = db_graph_find_str(&graph, graphseq[0]);
dBNode next_node = db_graph_find_str(&graph, graphseq[0]+1);
TASSERT(node.key != HASH_NOT_FOUND);
TASSERT(next_node.key != HASH_NOT_FOUND);
BinaryKmer bkey = db_node_get_bkmer(&graph, node.key);
Edges edges = db_node_get_edges(&graph, node.key, 0);
dBNode next_nodes[4];
Nucleotide next_nucs[4];
size_t i, p, num_next, next_idx;
num_next = db_graph_next_nodes(&graph, bkey, node.orient, edges,
next_nodes, next_nucs);
next_idx = 0;
while(next_idx < num_next && !db_nodes_are_equal(next_nodes[next_idx],next_node))
next_idx++;
TASSERT(next_idx < num_next && db_nodes_are_equal(next_nodes[next_idx],next_node));
// Crawl in all colours
graph_crawler_fetch(&crawler, node, next_nodes, next_idx, num_next,
NULL, graph.num_of_cols, NULL, NULL, NULL);
TASSERT2(crawler.num_paths == 2, "crawler.num_paths: %u", crawler.num_paths);
// Fetch paths
dBNodeBuffer nbuf;
db_node_buf_alloc(&nbuf, 16);
StrBuf sbuf;
strbuf_alloc(&sbuf, 128);
for(p = 0; p < crawler.num_paths; p++) {
db_node_buf_reset(&nbuf);
graph_crawler_get_path_nodes(&crawler, p, &nbuf);
strbuf_ensure_capacity(&sbuf, nbuf.len+graph.kmer_size);
sbuf.end = db_nodes_to_str(nbuf.b, nbuf.len, &graph, sbuf.b);
for(i = 0; i < 3 && strcmp(graphseq[i]+1,sbuf.b) != 0; i++) {}
TASSERT2(i < 3, "seq: %s", sbuf.b);
TASSERT2(sbuf.end == 75, "sbuf.end: %zu", sbuf.end);
TASSERT2(nbuf.len == 65, "nbuf.len: %zu", nbuf.len);
}
strbuf_dealloc(&sbuf);
db_node_buf_dealloc(&nbuf);
graph_crawler_dealloc(&crawler);
db_graph_dealloc(&graph);
}
// Walk the graph remembering the last time we met the ref
// When traversal fails, dump sequence up to last meeting with the ref
static void follow_break(BreakpointCaller *caller, dBNode node)
{
size_t i, j, k, num_next;
dBNode next_nodes[4];
Nucleotide next_nucs[4];
size_t nonref_idx[4], num_nonref_next = 0;
const dBGraph *db_graph = caller->db_graph;
BinaryKmer bkey = db_node_get_bkmer(db_graph, node.key);
Edges edges = db_node_get_edges(db_graph, node.key, 0);
num_next = db_graph_next_nodes(db_graph, bkey, node.orient, edges,
next_nodes, next_nucs);
// Filter out next nodes in the reference
for(i = 0; i < num_next; i++) {
if(kograph_num(caller->kograph, next_nodes[i].key) == 0) {
nonref_idx[num_nonref_next] = i;
num_nonref_next++;
}
}
// Abandon if all options are in ref or none are
if(num_nonref_next == num_next || num_nonref_next == 0) return;
// Follow all paths not in ref, in all colours
GraphCrawler *fw_crawler = &caller->crawlers[node.orient];
GraphCrawler *rv_crawler = &caller->crawlers[!node.orient];
dBNodeBuffer *allelebuf = &caller->allelebuf, *flank5pbuf = &caller->flank5pbuf;
GCMultiColPath *flank5p_multicolpath, *allele_multicolpath;
KOccurRun *flank5p_runs, *flank3p_runs;
size_t flank5p_pathid, allele_pathid;
size_t num_flank5p_runs, num_flank3p_runs;
// We fetch 5' flanks in all colours then merge matching paths
// we stop fetching a single path if it stops tracking the reference
// Alternatively, we could fetch the 5' flank in everyone and stop after a
// given distance, then check for that set of paths how much it tracks the
// reference. This has the advantage of scaling much better with number of
// samples, but not so well as min_ref_nkmers increases (since we fetch
// many flanks that can't be used) - I think this is less of a worry.
// Loop over possible next nodes at this junction
for(i = 0; i < num_nonref_next; i++)
{
size_t next_idx = nonref_idx[i];
// Go backwards to get 5p flank
traverse_5pflank(caller, rv_crawler, db_node_reverse(next_nodes[next_idx]),
db_node_reverse(node));
// Loop over the flanks we got
for(j = 0; j < rv_crawler->num_paths; j++)
{
// Get 5p flank
db_node_buf_reset(flank5pbuf);
graph_crawler_get_path_nodes(rv_crawler, j, flank5pbuf);
flank5p_multicolpath = &rv_crawler->multicol_paths[j];
flank5p_pathid = flank5p_multicolpath->pathid;
// Fetch 3pflank ref position
num_flank5p_runs = caller->flank5p_refs[flank5p_pathid].num_runs;
flank5p_runs = fetch_ref_contact(&rv_crawler->cache, flank5p_pathid,
caller->flank5p_refs,
&caller->flank5p_run_buf);
koruns_reverse(flank5p_runs, num_flank5p_runs, flank5pbuf->len);
koruns_sort_by_qoffset(flank5p_runs, num_flank5p_runs);
db_nodes_reverse_complement(flank5pbuf->data, flank5pbuf->len);
if(num_flank5p_runs > 0)
{
// Reset caller
kmer_run_buf_reset(&caller->koruns_3p);
kmer_run_buf_reset(&caller->koruns_3p_ended);
kmer_run_buf_reset(&caller->allele_run_buf);
// functions gcrawler_path_stop_at_ref_covg(),
// gcrawler_path_finish_ref_covg()
// both fill koruns_3p, koruns_3p_ended and allele_run_buf
// Only traverse in the colours we have a flank for
graph_crawler_fetch(fw_crawler, node,
next_nodes, next_nucs, next_idx, num_next,
flank5p_multicolpath->cols,
flank5p_multicolpath->num_cols,
gcrawler_path_stop_at_ref_covg,
gcrawler_path_finish_ref_covg,
caller);
// Assemble contigs - fetch forwards for each path for given 5p flank
for(k = 0; k < fw_crawler->num_paths; k++)
{
// Fetch nodes
db_node_buf_reset(allelebuf);
graph_crawler_get_path_nodes(fw_crawler, k, allelebuf);
ctx_assert(allelebuf->len > 0);
allele_multicolpath = &fw_crawler->multicol_paths[k];
allele_pathid = allele_multicolpath->pathid;
// Fetch 3pflank ref position
num_flank3p_runs = caller->allele_refs[allele_pathid].num_runs;
flank3p_runs = fetch_ref_contact(&fw_crawler->cache, allele_pathid,
caller->allele_refs,
&caller->allele_run_buf);
process_contig(caller,
allele_multicolpath->cols,
allele_multicolpath->num_cols,
flank5pbuf, allelebuf,
flank5p_runs, num_flank5p_runs,
flank3p_runs, num_flank3p_runs);
}
}
}
}
}