9c4b7225d91f5180fcddbecd843b71c4e6503688
angie
  Tue Mar 30 10:39:22 2021 -0700
Add subtree JSON URLs to single-subtree JSON, using Auspice's new url attribute.  Allow up to 1000 VCF samples and extend timeout to 15 minutes.

diff --git src/hg/hgPhyloPlace/phyloPlace.c src/hg/hgPhyloPlace/phyloPlace.c
index 80ed662..0583fc3 100644
--- src/hg/hgPhyloPlace/phyloPlace.c
+++ src/hg/hgPhyloPlace/phyloPlace.c
@@ -1,2327 +1,2336 @@
 /* Place SARS-CoV-2 sequences in phylogenetic tree using usher program. */
 
 /* Copyright (C) 2020 The Regents of the University of California */
 
 #include "common.h"
 #include "bigBed.h"
 #include "cheapcgi.h"
 #include "errCatch.h"
 #include "fa.h"
 #include "genePred.h"
 #include "hCommon.h"
 #include "hash.h"
 #include "hgConfig.h"
 #include "htmshell.h"
 #include "hui.h"
 #include "iupac.h"
 #include "jsHelper.h"
 #include "linefile.h"
 #include "obscure.h"
 #include "parsimonyProto.h"
 #include "phyloPlace.h"
 #include "phyloTree.h"
 #include "pipeline.h"
 #include "psl.h"
 #include "ra.h"
 #include "regexHelper.h"
 #include "trashDir.h"
 #include "vcf.h"
 
 // Globals:
 static boolean measureTiming = FALSE;
 
 // wuhCor1-specific:
 char *chrom = "NC_045512v2";
 int chromSize = 29903;
 
 // Parameter constants:
-int maxGenotypes = 100;        // Upper limit on number of samples user can upload at once.
+int maxGenotypes = 1000;        // Upper limit on number of samples user can upload at once.
 boolean showBestNodePaths = FALSE;
 boolean showParsimonyScore = FALSE;
 
 
 char *phyloPlaceDbSetting(char *db, char *settingName)
 /* Return a setting from hgPhyloPlaceData/<db>/config.ra or NULL if not found. */
 {
 static struct hash *configHash = NULL;
 static char *configDb = NULL;
 if (!sameOk(db, configDb))
     {
     char configFile[1024];
     safef(configFile, sizeof configFile, PHYLOPLACE_DATA_DIR "/%s/config.ra", db);
     if (fileExists(configFile))
         {
         configHash = raReadSingle(configFile);
         configDb = cloneString(db);
         }
     }
 if (sameOk(db, configDb))
     return cloneString(hashFindVal(configHash, settingName));
 return NULL;
 }
 
 char *phyloPlaceDbSettingPath(char *db, char *settingName)
 /* Return path to a file named by a setting from hgPhyloPlaceData/<db>/config.ra,
  * or NULL if not found.  (Append hgPhyloPlaceData/<db>/ to the beginning of relative path) */
 {
 char *fileName = phyloPlaceDbSetting(db, settingName);
 if (isNotEmpty(fileName) && fileName[0] != '/' && !fileExists(fileName))
     {
     struct dyString *dy = dyStringCreate(PHYLOPLACE_DATA_DIR "/%s/%s", db, fileName);
     if (fileExists(dy->string))
         return dyStringCannibalize(&dy);
     else
         return NULL;
     }
 return fileName;
 }
 
 char *getUsherPath(boolean abortIfNotFound)
 /* Return hgPhyloPlaceData/usher if it exists, else NULL.  Do not free the returned value. */
 {
 char *usherPath = PHYLOPLACE_DATA_DIR "/usher";
 if (fileExists(usherPath))
     return usherPath;
 else if (abortIfNotFound)
     errAbort("Missing required file %s", usherPath);
 return NULL;
 }
 
 char *getUsherAssignmentsPath(char *db, boolean abortIfNotFound)
 /* If <db>/config.ra specifies the file for use by usher --load-assignments and the file exists,
  * return the path, else NULL.  Do not free the returned value. */
 {
 char *usherAssignmentsPath = phyloPlaceDbSettingPath(db, "usherAssignmentsFile");
 if (isNotEmpty(usherAssignmentsPath) && fileExists(usherAssignmentsPath))
     return usherAssignmentsPath;
 else if (abortIfNotFound)
     errAbort("Missing required file %s", usherAssignmentsPath);
 return NULL;
 }
 
 //#*** This needs to go in a lib so CGIs know whether to include it in the menu. needs better name.
 boolean hgPhyloPlaceEnabled()
 /* Return TRUE if hgPhyloPlace is enabled in hg.conf and db wuhCor1 exists. */
 {
 char *cfgSetting = cfgOption("hgPhyloPlaceEnabled");
 boolean isEnabled = (isNotEmpty(cfgSetting) &&
                      differentWord(cfgSetting, "off") && differentWord(cfgSetting, "no"));
 return (isEnabled && hDbExists("wuhCor1"));
 }
 
 static void addPathIfNecessary(struct dyString *dy, char *db, char *fileName)
 /* If fileName exists, copy it into dy, else try hgPhyloPlaceData/<db>/fileName */
 {
 dyStringClear(dy);
 if (fileExists(fileName))
     dyStringAppend(dy, fileName);
 else
     dyStringPrintf(dy, PHYLOPLACE_DATA_DIR "/%s/%s", db, fileName);
 }
 
 struct treeChoices *loadTreeChoices(char *db)
 /* If <db>/config.ra specifies a treeChoices file, load it up, else return NULL. */
 {
 struct treeChoices *treeChoices = NULL;
 char *filename = phyloPlaceDbSettingPath(db, "treeChoices");
 if (isNotEmpty(filename) && fileExists(filename))
     {
     AllocVar(treeChoices);
     int maxChoices = 128;
     AllocArray(treeChoices->protobufFiles, maxChoices);
     AllocArray(treeChoices->metadataFiles, maxChoices);
     AllocArray(treeChoices->sources, maxChoices);
     AllocArray(treeChoices->descriptions, maxChoices);
     struct lineFile *lf = lineFileOpen(filename, TRUE);
     char *line;
     while (lineFileNextReal(lf, &line))
         {
         char *words[5];
         int wordCount = chopTabs(line, words);
         lineFileExpectWords(lf, 4, wordCount);
         if (treeChoices->count >= maxChoices)
             {
             warn("File %s has too many lines, only showing first %d phylogenetic tree choices",
                  filename, maxChoices);
             break;
             }
         struct dyString *dy = dyStringNew(0);
         addPathIfNecessary(dy, db, words[0]);
         treeChoices->protobufFiles[treeChoices->count] = cloneString(dy->string);
         addPathIfNecessary(dy, db, words[1]);
         treeChoices->metadataFiles[treeChoices->count] = cloneString(dy->string);
         treeChoices->sources[treeChoices->count] = cloneString(words[2]);
         // Description can be either a file or just some text.
         addPathIfNecessary(dy, db, words[3]);
         if (fileExists(dy->string))
             {
             char *desc = NULL;
             readInGulp(dy->string, &desc, NULL);
             treeChoices->descriptions[treeChoices->count] = desc;
             }
         else
             treeChoices->descriptions[treeChoices->count] = cloneString(words[3]);
         treeChoices->count++;
         dyStringFree(&dy);
         }
     lineFileClose(&lf);
     }
 return treeChoices;
 }
 
 static char *urlFromTn(struct tempName *tn)
 /* Make a full URL to a trash file that our net.c code will be able to follow, for when we can't
  * just leave it up to the user's web browser to do the right thing with "../". */
 {
 struct dyString *dy = dyStringCreate("%s%s", hLocalHostCgiBinUrl(), tn->forHtml);
 return dyStringCannibalize(&dy);
 }
 
 void reportTiming(int *pStartTime, char *message)
 /* Print out a report to stderr of how much time something took. */
 {
 if (measureTiming)
     {
     int now = clock1000();
     fprintf(stderr, "%dms to %s\n", now - *pStartTime, message);
     *pStartTime = now;
     }
 }
 
 static boolean lfLooksLikeFasta(struct lineFile *lf)
 /* Peek at file to see if it looks like FASTA, i.e. begins with a >header. */
 {
 boolean hasFastaHeader = FALSE;
 char *line;
 if (lineFileNext(lf, &line, NULL))
     {
     if (line[0] == '>')
         hasFastaHeader = TRUE;
     lineFileReuse(lf);
     }
 return hasFastaHeader;
 }
 
 static void rInformativeBasesFromTree(struct phyloTree *node, boolean *informativeBases)
 /* For each variant associated with a non-leaf node, set informativeBases[chromStart]. */
 {
 if (node->numEdges > 0)
     {
     if (node->priv)
         {
         struct singleNucChange *snc, *sncs = node->priv;
         for (snc = sncs;  snc != NULL;  snc = snc->next)
             informativeBases[snc->chromStart] = TRUE;
         }
     int i;
     for (i = 0;  i < node->numEdges;  i++)
         rInformativeBasesFromTree(node->edges[i], informativeBases);
     }
 }
 
 static boolean *informativeBasesFromTree(struct phyloTree *bigTree, struct slName **maskSites)
 /* Return an array indexed by reference position with TRUE at positions that have a non-leaf
  * variant in bigTree. */
 {
 boolean *informativeBases;
 AllocArray(informativeBases, chromSize);
 if (bigTree)
     {
     rInformativeBasesFromTree(bigTree, informativeBases);
     int i;
     for (i = 0;  i < chromSize;  i++)
         {
         struct slName *maskedReasons = maskSites[i];
         if (maskedReasons && informativeBases[i])
             {
             warn("protobuf tree contains masked mutation at %d (%s)", i+1, maskedReasons->name);
             informativeBases[i] = FALSE;
             }
         }
     }
 return informativeBases;
 }
 
 static boolean lfLooksLikeVcf(struct lineFile *lf)
 /* Peek at file to see if it looks like VCF, i.e. begins with a ##fileformat=VCF header. */
 {
 boolean hasVcfHeader = FALSE;
 char *line;
 if (lineFileNext(lf, &line, NULL))
     {
     if (startsWith("##fileformat=VCF", line))
         hasVcfHeader = TRUE;
     lineFileReuse(lf);
     }
 return hasVcfHeader;
 }
 
 static struct tempName *checkAndSaveVcf(struct lineFile *lf, struct dnaSeq *refGenome,
                                         struct slName **maskSites, struct seqInfo **retSeqInfoList,
                                         struct slName **retSampleIds)
 /* Save the contents of lf to a trash file.  If it has a reasonable number of genotype columns
  * with recognizable genotypes, and the coordinates seem to be in range, then return the path
  * to the trash file.  Otherwise complain and return NULL. */
 {
 struct tempName *tn;
 AllocVar(tn);
 trashDirFile(tn, "ct", "ct_pp", ".vcf");
 FILE *f = mustOpen(tn->forCgi, "w");
 struct seqInfo *seqInfoList = NULL;
 struct slName *sampleIds = NULL;
 struct errCatch *errCatch = errCatchNew();
 if (errCatchStart(errCatch))
     {
     char *line;
     int lineSize;
     int sampleCount = 0;
     while (lineFileNext(lf, &line, &lineSize))
         {
         if (startsWith("#CHROM\t", line))
             {
             //#*** TODO: if the user uploads a sample with the same ID as one already in the
             //#*** saved assignment file, then usher will ignore it!
             //#*** Better check for that and warn the user.
             int colCount = chopTabs(line, NULL);
             if (colCount == 1)
                 {
                 lineFileAbort(lf, "VCF requires tab-separated columns, but no tabs found");
                 }
             sampleCount = colCount - VCF_NUM_COLS_BEFORE_GENOTYPES;
             if (sampleCount < 1 || sampleCount > maxGenotypes)
                 {
                 if (sampleCount < 1)
                     lineFileAbort(lf, "VCF header #CHROM line has %d columns; expecting at least %d "
                                   "columns including sample IDs for genotype columns",
                                   colCount, 10);
                 else
                     lineFileAbort(lf, "VCF header #CHROM line defines %d samples but only up to %d "
                                   "are supported",
                                   sampleCount, maxGenotypes);
                 }
             char lineCopy[lineSize+1];
             safecpy(lineCopy, sizeof lineCopy, line);
             char *words[colCount];
             chopTabs(lineCopy, words);
             struct hash *uniqNames = hashNew(0);
             int i;
             for (i = VCF_NUM_COLS_BEFORE_GENOTYPES;  i < colCount;  i++)
                 {
                 if (hashLookup(uniqNames, words[i]))
                     lineFileAbort(lf, "VCF sample names in #CHROM line must be unique, but '%s' "
                                   "appears more than once", words[i]);
                 hashAdd(uniqNames, words[i], NULL);
                 slNameAddHead(&sampleIds, words[i]);
                 struct seqInfo *si;
                 AllocVar(si);
                 si->seq = cloneDnaSeq(refGenome);
                 si->seq->name = cloneString(words[i]);
                 slAddHead(&seqInfoList, si);
                 }
             slReverse(&seqInfoList);
             slReverse(&sampleIds);
             hashFree(&uniqNames);
             fputs(line, f);
             fputc('\n', f);
             }
         else if (line[0] == '#')
             {
             fputs(line, f);
             fputc('\n', f);
             }
         else
             {
             if (sampleCount < 1)
                 {
                 lineFileAbort(lf, "VCF header did not include #CHROM line defining sample IDs for "
                               "genotype columns");
                 }
             int colCount = chopTabs(line, NULL);
             int genotypeCount = colCount - VCF_NUM_COLS_BEFORE_GENOTYPES;
             if (genotypeCount != sampleCount)
                 {
                 lineFileAbort(lf, "VCF header defines %d samples but there are %d genotype columns",
                               sampleCount, genotypeCount);
                 }
             char *words[colCount];
             chopTabs(line, words);
             //#*** TODO: check that POS is sorted
             int pos = strtol(words[1], NULL, 10);
             if (pos > chromSize)
                 {
                 lineFileAbort(lf, "VCF POS value %d exceeds size of reference sequence (%d)",
                               pos, chromSize);
                 }
             // make sure REF value (if given) matches reference genome
             int chromStart = pos - 1;
             struct slName *maskedReasons = maskSites[chromStart];
             char *ref = words[3];
             if (strlen(ref) != 1)
                 {
                 // Not an SNV -- skip it.
                 //#*** should probably report or at least count these...
                 continue;
                 }
             char refBase = toupper(refGenome->dna[chromStart]);
             if (ref[0] == '*' || ref[0] == '.')
                 ref[0] = refBase;
             else if (ref[0] != refBase)
                 lineFileAbort(lf, "VCF REF value at position %d is '%s', expecting '%c' "
                               "(or '*' or '.')",
                               pos, ref, refBase);
             char altStrCopy[strlen(words[4])+1];
             safecpy(altStrCopy, sizeof altStrCopy, words[4]);
             char *alts[strlen(words[4])+1];
             chopCommas(altStrCopy, alts);
             //#*** Would be nice to trim out indels from ALT column -- but that would require
             //#*** adjusting genotype codes below.
             struct seqInfo *si = seqInfoList;
             int i;
             for (i = VCF_NUM_COLS_BEFORE_GENOTYPES;  i < colCount;  i++, si = si->next)
                 {
                 if (words[i][0] != '.' && !isdigit(words[i][0]))
                     {
                     lineFileAbort(lf, "VCF genotype columns must contain numeric allele codes; "
                                   "can't parse '%s'", words[i]);
                     }
                 else
                     {
                     if (words[i][0] == '.')
                         {
                         si->seq->dna[chromStart] = 'n';
                         si->nCountMiddle++;
                         }
                     else
                         {
                         int alIx = atol(words[i]);
                         if (alIx > 0)
                             {
                             char *alt = alts[alIx-1];
                             if (strlen(alt) == 1)
                                 {
                                 si->seq->dna[chromStart] = alt[0];
                                 struct singleNucChange *snc = sncNew(chromStart, ref[0], '\0',
                                                                      alt[0]);
                                 if (maskedReasons)
                                     {
                                     slAddHead(&si->maskedSncList, snc);
                                     slAddHead(&si->maskedReasonsList, slRefNew(maskedReasons));
                                     }
                                 else
                                     {
                                     if (isIupacAmbiguous(alt[0]))
                                         si->ambigCount++;
                                     slAddHead(&si->sncList, snc);
                                     }
                                 }
                             }
                         }
                     }
                 }
             if (!maskedReasons)
                 {
                 fputs(chrom, f);
                 for (i = 1;  i < colCount;  i++)
                     {
                     fputc('\t', f);
                     fputs(words[i], f);
                     }
                 fputc('\n', f);
                 }
             }
         }
     }
 errCatchEnd(errCatch);
 carefulClose(&f);
 if (errCatch->gotError)
     {
     warn("%s", errCatch->message->string);
     unlink(tn->forCgi);
     freez(&tn);
     }
 errCatchFree(&errCatch); 
 struct seqInfo *si;
 for (si = seqInfoList;  si != NULL;  si = si->next)
     slReverse(&si->sncList);
 *retSeqInfoList = seqInfoList;
 *retSampleIds = sampleIds;
 return tn;
 }
 
 static void displaySampleMuts(struct placementInfo *info)
 {
 printf("<p>Differences from the reference genome "
        "(<a href='https://www.ncbi.nlm.nih.gov/nuccore/NC_045512.2' target=_blank>"
        "NC_045512.2</a>): ");
 if (info->sampleMuts == NULL)
     printf("(None; identical to reference)");
 else
     {
     struct slName *sln;
     for (sln = info->sampleMuts;  sln != NULL;  sln = sln->next)
         {
         if (sln != info->sampleMuts)
             printf(", ");
         printf("%s", sln->name);
         }
     }
 puts("</p>");
 }
 
 static void variantPathPrint(struct variantPathNode *variantPath)
 /* Print out a variantPath; print nodeName only if non-numeric
  * (i.e. a sample ID not internal node) */
 {
 struct variantPathNode *vpn;
 for (vpn = variantPath;  vpn != NULL;  vpn = vpn->next)
     {
     if (vpn != variantPath)
         printf(" > ");
     if (!isAllDigits(vpn->nodeName))
         printf("%s: ", vpn->nodeName);
     struct singleNucChange *snc;
     for (snc = vpn->sncList;  snc != NULL;  snc = snc->next)
         {
         if (snc != vpn->sncList)
             printf(", ");
         printf("%c%d%c", snc->parBase, snc->chromStart+1, snc->newBase);
         }
     }
 }
 
 static void displayVariantPath(struct variantPathNode *variantPath, char *sampleId)
 /* Display mutations on the path to this sample. */
 {
 printf("<p>Mutations along the path from the root of the phylogenetic tree to %s:<br>",
        sampleId);
 if (variantPath)
     {
     variantPathPrint(variantPath);
     puts("<br>");
     }
 else
     puts("(None; your sample was placed at the root of the phylogenetic tree)");
 puts("</p>");
 }
 
 static boolean isInternalNodeName(char *nodeName, int minNewNode)
 /* Return TRUE if nodeName looks like an internal node ID from the protobuf tree, i.e. is numeric
  * and less than minNewNode. */
 {
 return isAllDigits(nodeName) && (atoi(nodeName) < minNewNode);
 }
 
 static struct variantPathNode *findLastInternalNode(struct variantPathNode *variantPath,
                                                     int minNewNode)
 /* Return the last node in variantPath with a numeric name less than minNewNode, or NULL. */
 {
 if (!variantPath || !isInternalNodeName(variantPath->nodeName, minNewNode))
     return NULL;
 while (variantPath->next && isInternalNodeName(variantPath->next->nodeName, minNewNode))
     variantPath = variantPath->next;
 if (variantPath && isInternalNodeName(variantPath->nodeName, minNewNode))
     return variantPath;
 return NULL;
 }
 
 static int mutCountCmp(const void *a, const void *b)
 /* Compare number of mutations of phyloTree nodes a and b. */
 {
 const struct phyloTree *nodeA = *(struct phyloTree * const *)a;
 const struct phyloTree *nodeB = *(struct phyloTree * const *)b;
 return slCount(nodeA->priv) - slCount(nodeB->priv);
 }
 
 static struct slName *findNearestNeighbor(struct mutationAnnotatedTree *bigTree, char *sampleId,
                                           struct variantPathNode *variantPath)
 /* Use the sequence of mutations in variantPath to find sampleId's parent node in bigTree,
  * then look for most similar leaf sibling(s). */
 {
 struct slName *neighbors = NULL;
 int bigTreeINodeCount = phyloCountInternalNodes(bigTree->tree);
 int minNewNode = bigTreeINodeCount + 1; // 1-based
 struct variantPathNode *lastOldNode = findLastInternalNode(variantPath, minNewNode);
 struct phyloTree *node = lastOldNode ? hashFindVal(bigTree->nodeHash, lastOldNode->nodeName) :
                                        bigTree->tree;
 if (lastOldNode && !node)
     errAbort("Can't find last internal node for sample %s", sampleId);
 // Look for a leaf kid with no mutations relative to the parent, should be closest.
 if (node->numEdges == 0)
     {
     struct slName *nodeList = hashFindVal(bigTree->condensedNodes, node->ident->name);
     if (nodeList)
         slNameAddHead(&neighbors, nodeList->name);
     else
         slNameAddHead(&neighbors, node->ident->name);
     }
 else
     {
     int leafCount = 0;
     int i;
     for (i = 0;  i < node->numEdges;  i++)
         {
         struct phyloTree *kid = node->edges[i];
         if (kid->numEdges == 0)
             {
             leafCount++;
             struct singleNucChange *kidMuts = kid->priv;
             if (!kidMuts)
                 {
                 struct slName *nodeList = hashFindVal(bigTree->condensedNodes, kid->ident->name);
                 if (nodeList)
                     slNameAddHead(&neighbors, nodeList->name);
                 else
                     slNameAddHead(&neighbors, kid->ident->name);
                 break;
                 }
             }
         }
     if (neighbors == NULL && leafCount)
         {
         // Pick the leaf with the fewest mutations.
         struct phyloTree *leafKids[leafCount];
         int leafIx = 0;
         for (i = 0;  i < node->numEdges;  i++)
             {
             struct phyloTree *kid = node->edges[i];
             if (kid->numEdges == 0)
                 leafKids[leafIx++] = kid;
             }
         qsort(leafKids, leafCount, sizeof(leafKids[0]), mutCountCmp);
         neighbors = slNameNew(leafKids[0]->ident->name);
         }
     }
 return neighbors;
 }
 
 static void printVariantPathNoNodeNames(FILE *f, struct variantPathNode *variantPath)
 /* Print out variant path with no node names (even if non-numeric) to f. */
 {
 struct variantPathNode *vpn;
 for (vpn = variantPath;  vpn != NULL;  vpn = vpn->next)
     {
     if (vpn != variantPath)
         fprintf(f, " > ");
     struct singleNucChange *snc;
     for (snc = vpn->sncList;  snc != NULL;  snc = snc->next)
         {
         if (snc != vpn->sncList)
             fprintf(f, ", ");
         fprintf(f, "%c%d%c", snc->parBase, snc->chromStart+1, snc->newBase);
         }
     }
 }
 
 static struct hash *getSampleMetadata(char *metadataFile)
 /* If config.ra defines a metadataFile, load its contents into a hash indexed by EPI ID and return;
  * otherwise return NULL. */
 {
 struct hash *sampleMetadata = NULL;
 if (isNotEmpty(metadataFile) && fileExists(metadataFile))
     {
     sampleMetadata = hashNew(0);
     struct lineFile *lf = lineFileOpen(metadataFile, TRUE);
     int headerWordCount = 0;
     char **headerWords = NULL;
     char *line;
     // Check for header line
     if (lineFileNext(lf, &line, NULL))
         {
         if (startsWithWord("strain", line))
             {
             char *headerLine = cloneString(line);
             headerWordCount = chopString(headerLine, "\t", NULL, 0);
             AllocArray(headerWords, headerWordCount);
             chopString(headerLine, "\t", headerWords, headerWordCount);
             }
         else
             errAbort("Missing header line from metadataFile %s", metadataFile);
         }
     int strainIx = stringArrayIx("strain", headerWords, headerWordCount);
     int epiIdIx = stringArrayIx("gisaid_epi_isl", headerWords, headerWordCount);
     int genbankIx = stringArrayIx("genbank_accession", headerWords, headerWordCount);
     int dateIx = stringArrayIx("date", headerWords, headerWordCount);
     int authorIx = stringArrayIx("authors", headerWords, headerWordCount);
     int nCladeIx = stringArrayIx("Nextstrain_clade", headerWords, headerWordCount);
     int gCladeIx = stringArrayIx("GISAID_clade", headerWords, headerWordCount);
     int lineageIx = stringArrayIx("pangolin_lineage", headerWords, headerWordCount);
+    if (lineageIx < 0)
+        lineageIx = stringArrayIx("pango_lineage", headerWords, headerWordCount);
     int countryIx = stringArrayIx("country", headerWords, headerWordCount);
     int divisionIx = stringArrayIx("division", headerWords, headerWordCount);
     int locationIx = stringArrayIx("location", headerWords, headerWordCount);
     int countryExpIx = stringArrayIx("country_exposure", headerWords, headerWordCount);
     int divExpIx = stringArrayIx("division_exposure", headerWords, headerWordCount);
     int origLabIx = stringArrayIx("originating_lab", headerWords, headerWordCount);
     int subLabIx = stringArrayIx("submitting_lab", headerWords, headerWordCount);
     int regionIx = stringArrayIx("region", headerWords, headerWordCount);
     while (lineFileNext(lf, &line, NULL))
         {
         char *words[headerWordCount];
         int wordCount = chopTabs(line, words);
         lineFileExpectWords(lf, headerWordCount, wordCount);
         struct sampleMetadata *met;
         AllocVar(met);
         if (strainIx >= 0)
             met->strain = cloneString(words[strainIx]);
         if (epiIdIx >= 0)
             met->epiId = cloneString(words[epiIdIx]);
         if (genbankIx >= 0 && !sameString("?", words[genbankIx]))
             met->gbAcc = cloneString(words[genbankIx]);
         if (dateIx >= 0)
             met->date = cloneString(words[dateIx]);
         if (authorIx >= 0)
             met->author = cloneString(words[authorIx]);
         if (nCladeIx >= 0)
             met->nClade = cloneString(words[nCladeIx]);
         if (gCladeIx >= 0)
             met->gClade = cloneString(words[gCladeIx]);
         if (lineageIx >= 0)
             met->lineage = cloneString(words[lineageIx]);
         if (countryIx >= 0)
             met->country = cloneString(words[countryIx]);
         if (divisionIx >= 0)
             met->division = cloneString(words[divisionIx]);
         if (locationIx >= 0)
             met->location = cloneString(words[locationIx]);
         if (countryExpIx >= 0)
             met->countryExp = cloneString(words[countryExpIx]);
         if (divExpIx >= 0)
             met->divExp = cloneString(words[divExpIx]);
         if (origLabIx >= 0)
             met->origLab = cloneString(words[origLabIx]);
         if (subLabIx >= 0)
             met->subLab = cloneString(words[subLabIx]);
         if (regionIx >= 0)
             met->region = cloneString(words[regionIx]);
         // If epiId and/or genbank ID is included, we'll probably be using that to look up items.
         if (epiIdIx >= 0 && !isEmpty(words[epiIdIx]))
             hashAdd(sampleMetadata, words[epiIdIx], met);
         if (genbankIx >= 0 && !isEmpty(words[genbankIx]) && !sameString("?", words[genbankIx]))
             {
             if (strchr(words[genbankIx], '.'))
                 {
                 // Index by versionless accession
                 char copy[strlen(words[genbankIx])+1];
                 safecpy(copy, sizeof copy, words[genbankIx]);
                 char *dot = strchr(copy, '.');
                 *dot = '\0';
                 hashAdd(sampleMetadata, copy, met);
                 }
             else
                 hashAdd(sampleMetadata, words[genbankIx], met);
             }
         if (strainIx >= 0 && !isEmpty(words[strainIx]))
             hashAdd(sampleMetadata, words[strainIx], met);
         }
     lineFileClose(&lf);
     }
 return sampleMetadata;
 }
 
 char *epiIdFromSampleName(char *sampleId)
 /* If an EPI_ISL_# ID is present somewhere in sampleId, extract and return it, otherwise NULL. */
 {
 char *epiId = cloneString(strstr(sampleId, "EPI_ISL_"));
 if (epiId)
     {
     char *p = epiId + strlen("EPI_ISL_");
     while (isdigit(*p))
         p++;
     *p = '\0';
     }
 return epiId;
 }
 
 char *gbIdFromSampleName(char *sampleId)
 /* If a GenBank accession is present somewhere in sampleId, extract and return it, otherwise NULL. */
 {
 char *gbId = NULL;
 regmatch_t substrs[2];
 if (regexMatchSubstr(sampleId, "([A-Z][A-Z][0-9]{6})", substrs, ArraySize(substrs)))
     {
     // Make sure there are word boundaries around the match
     if ((substrs[1].rm_so == 0 || !isalnum(sampleId[substrs[1].rm_so-1])) &&
         !isalnum(sampleId[substrs[1].rm_eo]))
         gbId = cloneStringZ(sampleId+substrs[1].rm_so, substrs[1].rm_eo - substrs[1].rm_so);
     }
 return gbId;
 }
 
 struct sampleMetadata *metadataForSample(struct hash *sampleMetadata, char *sampleId)
 /* Look up sampleId in sampleMetadata, by accession if sampleId seems to include an accession. */
 {
 struct sampleMetadata *met = NULL;
 if (sampleMetadata == NULL)
     return NULL;
 char *epiId = epiIdFromSampleName(sampleId);
 if (epiId)
     met = hashFindVal(sampleMetadata, epiId);
 if (!met)
     {
     char *gbId = gbIdFromSampleName(sampleId);
     if (gbId)
         met = hashFindVal(sampleMetadata, gbId);
     }
 if (!met)
     met = hashFindVal(sampleMetadata, sampleId);
 if (!met && strchr(sampleId, '|'))
     {
     char copy[strlen(sampleId)+1];
     safecpy(copy, sizeof copy, sampleId);
     char *words[4];
     int wordCount = chopString(copy, "|", words, ArraySize(words));
     if (isNotEmpty(words[0]))
         met = hashFindVal(sampleMetadata, words[0]);
     if (met == NULL && wordCount > 1 && isNotEmpty(words[1]))
         met = hashFindVal(sampleMetadata, words[1]);
     }
 // If it's one of our collapsed node names, dig out the example name and try that.
 if (!met && isdigit(sampleId[0]) && strstr(sampleId, "_from_"))
     {
     char *eg = strstr(sampleId, "_eg_");
     if (eg)
         met = hashFindVal(sampleMetadata, eg+strlen("_eg_"));
     }
 return met;
 }
 
 static char *lineageForSample(struct hash *sampleMetadata, char *sampleId)
 /* Look up sampleId's lineage in epiToLineage file. Return NULL if we don't find a match. */
 {
 char *lineage = NULL;
 struct sampleMetadata *met = metadataForSample(sampleMetadata, sampleId);
 if (met)
     lineage = met->lineage;
 return lineage;
 }
 
 static void displayNearestNeighbors(struct mutationAnnotatedTree *bigTree, char *source,
                                     struct placementInfo *info, struct hash *sampleMetadata)
 /* Use info->variantPaths to find sample's nearest neighbor(s) in tree. */
 {
 if (bigTree)
     {
     printf("<p>Nearest neighboring %s sequence already in phylogenetic tree: ", source);
     struct slName *neighbors = findNearestNeighbor(bigTree, info->sampleId, info->variantPath);
     struct slName *neighbor;
     for (neighbor = neighbors;  neighbor != NULL;  neighbor = neighbor->next)
         {
         if (neighbor != neighbors)
             printf(", ");
         printf("%s", neighbor->name);
         char *lineage = lineageForSample(sampleMetadata, neighbor->name);
         if (isNotEmpty(lineage))
             printf(": lineage %s", lineage);
         }
     puts("</p>");
     }
 }
 
 static void displayBestNodes(struct placementInfo *info, struct hash *sampleMetadata)
 /* Show the node(s) most closely related to sample. */
 {
 if (info->bestNodeCount == 1)
     printf("<p>The placement in the tree is unambiguous; "
            "there are no other parsimony-optimal placements in the phylogenetic tree.</p>\n");
 else if (info->bestNodeCount > 1)
     printf("<p>This placement is not the only parsimony-optimal placement in the tree; "
            "%d other placements exist.</p>\n", info->bestNodeCount - 1);
 if (showBestNodePaths && info->bestNodes)
     {
     if (info->bestNodeCount != slCount(info->bestNodes))
         errAbort("Inconsistent bestNodeCount (%d) and number of bestNodes (%d)",
                  info->bestNodeCount, slCount(info->bestNodes));
     if (info->bestNodeCount > 1)
         printf("<ul><li><b>used for placement</b>: ");
     if (differentString(info->bestNodes->name, "?") && !isAllDigits(info->bestNodes->name))
         printf("%s ", info->bestNodes->name);
     printVariantPathNoNodeNames(stdout, info->bestNodes->variantPath);
     struct bestNodeInfo *bn;
     for (bn = info->bestNodes->next;  bn != NULL;  bn = bn->next)
         {
         printf("\n<li>");
         if (differentString(bn->name, "?") && !isAllDigits(bn->name))
             printf("%s ", bn->name);
         printVariantPathNoNodeNames(stdout, bn->variantPath);
         char *lineage = lineageForSample(sampleMetadata, bn->name);
         if (isNotEmpty(lineage))
             printf(": lineage %s", lineage);
         }
     if (info->bestNodeCount > 1)
         puts("</ul>");
     puts("</p>");
     }
 }
 
 static int placementInfoRefCmpSampleMuts(const void *va, const void *vb)
 /* Compare slRef->placementInfo->sampleMuts lists.  Shorter lists first.  Using alpha sort
  * to distinguish between different sampleMuts contents arbitrarily; the purpose is to
  * clump samples with identical lists. */
 {
 struct slRef * const *rra = va;
 struct slRef * const *rrb = vb;
 struct placementInfo *pa = (*rra)->val;
 struct placementInfo *pb = (*rrb)->val;
 int diff = slCount(pa->sampleMuts) - slCount(pb->sampleMuts);
 if (diff == 0)
     {
     struct slName *slnA, *slnB;
     for (slnA = pa->sampleMuts, slnB = pb->sampleMuts;  slnA != NULL;
          slnA = slnA->next, slnB = slnB->next)
         {
         diff = strcmp(slnA->name, slnB->name);
         if (diff != 0)
             break;
         }
     }
 return diff;
 }
 
 static struct slRef *getPlacementRefList(struct slName *sampleIds, struct hash *samplePlacements)
 /* Look up sampleIds in samplePlacements and return ref list of placements. */
 {
 struct slRef *placementRefs = NULL;
 struct slName *sample;
 for (sample = sampleIds;  sample != NULL;  sample = sample->next)
     {
     struct placementInfo *info = hashFindVal(samplePlacements, sample->name);
     if (!info)
         errAbort("getPlacementRefList: can't find placement info for sample '%s'",
                  sample->name);
     slAddHead(&placementRefs, slRefNew(info));
     }
 slReverse(&placementRefs);
 return placementRefs;
 }
 
 static int countIdentical(struct slRef *placementRefs)
 /* Return the number of placements that have identical sampleMuts lists. */
 {
 int clumpCount = 0;
 struct slRef *ref;
 for (ref = placementRefs;  ref != NULL;  ref = ref->next)
     {
     clumpCount++;
     if (ref->next == NULL || placementInfoRefCmpSampleMuts(&ref, &ref->next))
         break;
     }
 return clumpCount;
 }
 
 static void asciiTree(struct phyloTree *node, char *indent, boolean isLast)
 /* Until we can make a real graphic, at least print an ascii tree. */
 {
 if (isNotEmpty(indent) || isNotEmpty(node->ident->name))
     {
     if (node->ident->name && !isAllDigits(node->ident->name))
         printf("%s %s\n", indent, node->ident->name);
     }
 int indentLen = strlen(indent);
 char indentForKids[indentLen+1];
 safecpy(indentForKids, sizeof indentForKids, indent);
 if (indentLen >= 4)
     {
     if (isLast)
         safecpy(indentForKids+indentLen - 4, 4 + 1, "    ");
     else
         safecpy(indentForKids+indentLen - 4, 4 + 1, "|   ");
     }
 if (node->numEdges > 0)
     {
     char kidIndent[strlen(indent)+5];
     safef(kidIndent, sizeof kidIndent, "%s%s", indentForKids, "+---");
     int i;
     for (i = 0;  i < node->numEdges;  i++)
         asciiTree(node->edges[i], kidIndent, (i == node->numEdges - 1));
     }
 }
 
 static void describeSamplePlacements(struct slName *sampleIds, struct hash *samplePlacements,
                                      struct phyloTree *subtree, struct hash *sampleMetadata,
                                      struct mutationAnnotatedTree *bigTree, char *source)
 /* Report how each sample fits into the big tree. */
 {
 // Sort sample placements by sampleMuts so we can group identical samples.
 struct slRef *placementRefs = getPlacementRefList(sampleIds, samplePlacements);
 slSort(&placementRefs, placementInfoRefCmpSampleMuts);
 int relatedCount = slCount(placementRefs);
 int clumpSize = countIdentical(placementRefs);
 if (clumpSize < relatedCount && relatedCount > 2)
     {
     // Not all of the related sequences are identical, so they will be broken down into
     // separate "clumps".  List all related samples first to avoid confusion.
     puts("<pre>");
     asciiTree(subtree, "", TRUE);
     puts("</pre>");
     }
 struct slRef *refsToGo = placementRefs;
 while ((clumpSize = countIdentical(refsToGo)) > 0)
     {
     struct slRef *ref = refsToGo;
     struct placementInfo *info = ref->val;
     if (clumpSize > 1)
         {
         // Sort identical samples alphabetically:
         struct slName *sortedSamples = NULL;
         int i;
         for (i = 0, ref = refsToGo;  ref != NULL && i < clumpSize;  ref = ref->next, i++)
             {
             info = ref->val;
             slNameAddHead(&sortedSamples, info->sampleId);
             }
         slNameSort(&sortedSamples);
         printf("<b>%d identical samples:</b>\n<ul>\n", clumpSize);
         struct slName *sln;
         for (sln = sortedSamples;  sln != NULL;  sln = sln->next)
             printf("<li><b>%s</b>\n", sln->name);
         puts("</ul>");
         }
     else
         {
         printf("<b>%s</b>\n", info->sampleId);
         ref = ref->next;
         }
     refsToGo = ref;
     displaySampleMuts(info);
     if (info->imputedBases)
         {
         puts("<p>Base values imputed by parsimony:\n<ul>");
         struct baseVal *bv;
         for (bv = info->imputedBases;  bv != NULL;  bv = bv->next)
             printf("<li>%d: %s\n", bv->chromStart+1, bv->val);
         puts("</ul>");
         puts("</p>");
         }
     displayVariantPath(info->variantPath, clumpSize == 1 ? info->sampleId : "samples");
     displayBestNodes(info, sampleMetadata);
     if (!showBestNodePaths)
         displayNearestNeighbors(bigTree, source, info, sampleMetadata);
     if (showParsimonyScore && info->parsimonyScore > 0)
         printf("<p>Parsimony score added by your sample: %d</p>\n", info->parsimonyScore);
         //#*** TODO: explain parsimony score
     }
 }
 
 struct phyloTree *phyloPruneToIds(struct phyloTree *node, struct slName *sampleIds)
 /* Prune all descendants of node that have no leaf descendants in sampleIds. */
 {
 if (node->numEdges)
     {
     struct phyloTree *prunedKids = NULL;
     int i;
     for (i = 0;  i < node->numEdges;  i++)
         {
         struct phyloTree *kidIntersected = phyloPruneToIds(node->edges[i], sampleIds);
         if (kidIntersected)
             slAddHead(&prunedKids, kidIntersected);
         }
     int kidCount = slCount(prunedKids);
     assert(kidCount <= node->numEdges);
     if (kidCount > 1)
         {
         slReverse(&prunedKids);
         // There is no phyloTreeFree, but if we ever add one, should use it here.
         node->numEdges = kidCount;
         struct phyloTree *kid;
         for (i = 0, kid = prunedKids;  i < kidCount;  i++, kid = kid->next)
             {
             node->edges[i] = kid;
             kid->parent = node;
             }
         }
     else
         return prunedKids;
     }
 else if (! (node->ident->name && slNameInList(sampleIds, node->ident->name)))
     node = NULL;
 return node;
 }
 
 static struct subtreeInfo *subtreeInfoForSample(struct subtreeInfo *subtreeInfoList, char *name,
                                                 int *retIx)
 /* Find the subtree that contains sample name and set *retIx to its index in the list.
  * If we can't find it, return NULL and set *retIx to -1. */
 {
 struct subtreeInfo *ti;
 int ix;
 for (ti = subtreeInfoList, ix = 0;  ti != NULL;  ti = ti->next, ix++)
     if (slNameInList(ti->subtreeUserSampleIds, name))
         break;
 if (ti == NULL)
     ix = -1;
 *retIx = ix;
 return ti;
 }
 
 static void lookForCladesAndLineages(struct seqInfo *seqInfoList, struct hash *samplePlacements,
                                      boolean *retGotClades, boolean *retGotLineages)
 /* See if UShER has annotated any clades and/or lineages for seqs. */
 {
 boolean gotClades = FALSE, gotLineages = FALSE;
 struct seqInfo *si;
 for (si = seqInfoList;  si != NULL;  si = si->next)
     {
     struct placementInfo *pi = hashFindVal(samplePlacements, si->seq->name);
     if (pi)
         {
         if (isNotEmpty(pi->nextClade))
             gotClades = TRUE;
         if (isNotEmpty(pi->pangoLineage))
             gotLineages = TRUE;
         if (gotClades && gotLineages)
             break;
         }
     }
 *retGotClades = gotClades;
 *retGotLineages = gotLineages;
 }
 
 static char *nextstrainHost()
 /* Return the nextstrain hostname from an hg.conf param, or NULL if missing. */
 {
 return cfgOption("nextstrainHost");
 }
 
 static char *nextstrainUrlFromTn(struct tempName *jsonTn)
 /* Return a link to Nextstrain to view an annotated subtree. */
 {
 char *jsonUrlForNextstrain = urlFromTn(jsonTn);
 char *protocol = strstr(jsonUrlForNextstrain, "://");
 if (protocol)
     jsonUrlForNextstrain = protocol + strlen("://");
 struct dyString *dy = dyStringCreate("%s/fetch/%s", nextstrainHost(), jsonUrlForNextstrain);
 return dyStringCannibalize(&dy);
 }
 
 static void makeNextstrainButton(char *id, struct tempName *tn, char *label, char *mouseover)
 /* Make a button to view an auspice JSON file in Nextstrain. */
 {
 char *nextstrainUrl = nextstrainUrlFromTn(tn);
 struct dyString *js = dyStringCreate("window.open('%s');", nextstrainUrl);
 cgiMakeOnClickButtonWithMsg(id, js->string, label, mouseover);
 dyStringFree(&js);
 freeMem(nextstrainUrl);
 }
 
 static void makeNextstrainButtonN(char *idBase, int ix, int userSampleCount, int subtreeSize,
                                   struct tempName *jsonTns[])
 /* Make a button to view one subtree in Nextstrain.  idBase is a short string and
  * ix is 0-based subtree number. */
 {
 char buttonId[256];
 safef(buttonId, sizeof buttonId, "%s%d", idBase, ix+1);
 char buttonLabel[256];
 safef(buttonLabel, sizeof buttonLabel, "view subtree %d in Nextstrain", ix+1);
 struct dyString *dyMo = dyStringCreate("view subtree %d with %d of your sequences and %d other "
                                        "sequences from the phylogenetic tree for context",
                                        ix+1, userSampleCount, subtreeSize - userSampleCount);
 makeNextstrainButton(buttonId, jsonTns[ix], buttonLabel, dyMo->string);
 dyStringFree(&dyMo);
 }
 
 static void makeNsSingleTreeButton(struct tempName *tn)
 /* Make a button to view single subtree (with all uploaded samples) in Nextstrain. */
 {
 makeNextstrainButton("viewNextstrainSingleSubtree", tn, "view single subtree in Nextstrain",
                      "view one subtree that includes all of your uploaded sequences plus "
                      SINGLE_SUBTREE_SIZE" randomly selected sequences from the phylogenetic "
                      "tree for context");
 }
 
 static void makeButtonRow(struct tempName *singleSubtreeJsonTn, struct tempName *jsonTns[],
                           struct subtreeInfo *subtreeInfoList, int subtreeSize, boolean isFasta)
 /* Russ's suggestion: row of buttons at the top to view results in GB, Nextstrain, Nextclade. */
 {
 puts("<p>");
 cgiMakeButtonWithMsg("submit", "view in Genome Browser",
                      "view your uploaded sequences, their phylogenetic relationship and their "
                      "mutations along with many other datasets available in the Genome Browser");
 if (nextstrainHost())
     {
     printf("&nbsp;");
     makeNsSingleTreeButton(singleSubtreeJsonTn);
     struct subtreeInfo *ti;
     int ix;
     for (ix = 0, ti = subtreeInfoList;  ti != NULL;  ti = ti->next, ix++)
         {
         int userSampleCount = slCount(ti->subtreeUserSampleIds);
         printf("&nbsp;");
         makeNextstrainButtonN("viewNextstrainTopRow", ix, userSampleCount, subtreeSize, jsonTns);
         }
     }
 if (0 && isFasta)
     {
     printf("&nbsp;");
     struct dyString *js = dyStringCreate("window.open('https://master.clades.nextstrain.org/"
                                          "?input-fasta=%s');",
                                          "needATn");  //#*** TODO: save FASTA to file
     cgiMakeOnClickButton("viewNextclade", js->string, "view sequences in Nextclade");
     }
 puts("</p>");
 }
 
 #define TOOLTIP(text) " <div class='tooltip'>(?)<span class='tooltiptext'>" text "</span></div>"
 
 static void printSummaryHeader(boolean isFasta, boolean gotClades, boolean gotLineages)
 /* Print the summary table header row with tooltips explaining columns. */
 {
 puts("<thead><tr>");
 if (isFasta)
     puts("<th>Fasta Sequence</th>\n"
          "<th>Size"
          TOOLTIP("Length of uploaded sequence in bases, excluding runs of N bases at "
                  "beginning and/or end")
          "</th>\n<th>#Ns"
          TOOLTIP("Number of 'N' bases in uploaded sequence, excluding runs of N bases at "
                  "beginning and/or end")
          "</th>");
 else
     puts("<th>VCF Sample</th>\n"
          "<th>#Ns"
          TOOLTIP("Number of no-call variants for this sample in uploaded VCF, "
                  "i.e. '.' used in genotype column")
          "</th>");
 puts("<th>#Mixed"
      TOOLTIP("Number of IUPAC ambiguous bases, e.g. 'R' for 'A or G'")
      "</th>");
 if (isFasta)
     puts("<th>Bases aligned"
          TOOLTIP("Number of bases aligned to reference NC_045512.2 Wuhan/Hu-1, including "
                  "matches and mismatches")
          "</th>\n<th>Inserted bases"
          TOOLTIP("Number of bases in aligned portion of uploaded sequence that are not present in "
                  "reference NC_045512.2 Wuhan/Hu-1")
          "</th>\n<th>Deleted bases"
          TOOLTIP("Number of bases in reference NC_045512.2 Wuhan/Hu-1 that are not "
                  "present in aligned portion of uploaded sequence")
          "</th>");
 puts("<th>#SNVs used for placement"
      TOOLTIP("Number of single-nucleotide variants in uploaded sample "
              "(does not include N's or mixed bases) used by UShER to place sample "
              "in phylogenetic tree")
      "</th>\n<th>#Masked SNVs"
      TOOLTIP("Number of single-nucleotide variants in uploaded sample that are masked "
              "(not used for placement) because they occur at known "
              "<a href='https://virological.org/t/issues-with-sars-cov-2-sequencing-data/473/12' "
              "target=_blank>Problematic Sites</a>"));;
 if (gotClades)
     puts("</th>\n<th>Nextstrain clade"
      TOOLTIP("The <a href='https://nextstrain.org/blog/2021-01-06-updated-SARS-CoV-2-clade-naming' "
              "target=_blank>Nextstrain clade</a> assigned to the sample by UShER"));
 if (gotLineages)
     puts("</th>\n<th>Pango lineage"
      TOOLTIP("The <a href='https://cov-lineages.org/' "
              "target=_blank>Pango lineage</a> assigned to the sample by UShER"));
 puts("</th>\n<th>Neighboring sample in tree"
      TOOLTIP("A sample already in the tree that is a child of the node at which the uploaded "
              "sample was placed, to give an example of a closely related sample")
      "</th>\n<th>Lineage of neighbor"
      TOOLTIP("The <a href='https://cov-lineages.org/' target=_blank>"
              "Pango lineage</a> assigned to the nearest neighboring sample already in the tree")
      "</th>\n<th>#Imputed values for mixed bases"
      TOOLTIP("If the uploaded sequence contains mixed/ambiguous bases, then UShER may assign "
              "values based on maximum parsimony")
      "</th>\n<th>#Maximally parsimonious placements"
      TOOLTIP("Number of potential placements in the tree with minimal parsimony score; "
              "the higher the number, the less confident the placement")
      "</th>\n<th>Parsimony score"
      TOOLTIP("Number of mutations/changes that must be added to the tree when placing the "
              "uploaded sample; the higher the number, the more diverged the sample")
      "</th>\n<th>Subtree number"
      TOOLTIP("Sequence number of subtree that contains this sample")
      "</th></tr></thead>");
 }
 
 
 // Default QC thresholds for calling an input sequence excellent/good/fair/bad [/fail]:
 static int qcThresholdsMinLength[] = { 29750, 29500, 29000, 28000 };
 static int qcThresholdsMaxNs[] = { 0, 5, 20, 100 };
 static int qcThresholdsMaxMixed[] = { 0, 5, 20, 100 };
 static int qcThresholdsMaxIndel[] = { 9, 18, 24, 36 };
 static int qcThresholdsMaxSNVs[] = { 25, 35, 45, 55 };
 static int qcThresholdsMaxMaskedSNVs[] = { 0, 1, 2, 3 };
 static int qcThresholdsMaxImputed[] = { 0, 5, 20, 100 };
 static int qcThresholdsMaxPlacements[] = { 1, 2, 3, 4 };
 static int qcThresholdsMaxPScore[] = { 0, 2, 5, 10 };
 
 static void wordsToQcThresholds(char **words, int *thresholds)
 /* Parse words from file into thresholds array.  Caller must ensure words and thresholds each
  * have 4 items. */
 {
 int i;
 for (i = 0;  i < 4;  i++)
     thresholds[i] = atoi(words[i]);
 }
 
 static void readQcThresholds(char *db)
 /* If config.ra specifies a file with QC thresholds for excellent/good/fair/bad [/fail],
  * parse it and replace the default values in qcThresholds arrays.  */
 {
 char *qcThresholdsFile = phyloPlaceDbSettingPath(db, "qcThresholds");
 if (isNotEmpty(qcThresholdsFile))
     {
     if (fileExists(qcThresholdsFile))
         {
         struct lineFile *lf = lineFileOpen(qcThresholdsFile, TRUE);
         char *line;
         while (lineFileNext(lf, &line, NULL))
             {
             char *words[16];
             int wordCount = chopTabs(line, words);
             lineFileExpectWords(lf, 5, wordCount);
             if (sameWord(words[0], "length"))
                 wordsToQcThresholds(words+1, qcThresholdsMinLength);
             else if (sameWord(words[0], "nCount"))
                 wordsToQcThresholds(words+1, qcThresholdsMaxNs);
             else if (sameWord(words[0], "mixedCount"))
                 wordsToQcThresholds(words+1, qcThresholdsMaxMixed);
             else if (sameWord(words[0], "indelCount"))
                 wordsToQcThresholds(words+1, qcThresholdsMaxIndel);
             else if (sameWord(words[0], "snvCount"))
                 wordsToQcThresholds(words+1, qcThresholdsMaxSNVs);
             else if (sameWord(words[0], "maskedSnvCount"))
                 wordsToQcThresholds(words+1, qcThresholdsMaxMaskedSNVs);
             else if (sameWord(words[0], "imputedBases"))
                 wordsToQcThresholds(words+1, qcThresholdsMaxImputed);
             else if (sameWord(words[0], "placementCount"))
                 wordsToQcThresholds(words+1, qcThresholdsMaxPlacements);
             else if (sameWord(words[0], "parsimony"))
                 wordsToQcThresholds(words+1, qcThresholdsMaxPScore);
             else
                 warn("qcThresholds file %s: unrecognized parameter '%s', skipping",
                      qcThresholdsFile, words[0]);
             }
         lineFileClose(&lf);
         }
     else
         warn("qcThresholds %s: file not found", qcThresholdsFile);
     }
 }
 
 static char *qcClassForIntMin(int n, int thresholds[])
 /* Return {qcExcellent, qcGood, qcMeh, qcBad or qcFail} depending on how n compares to the
  * thresholds. Don't free result. */
 {
 if (n >= thresholds[0])
     return "qcExcellent";
 else if (n >= thresholds[1])
     return "qcGood";
 else if (n >= thresholds[2])
     return "qcMeh";
 else if (n >= thresholds[3])
     return "qcBad";
 else
     return "qcFail";
 }
 
 static char *qcClassForLength(int length)
 /* Return qc class for length of sequence. */
 {
 return qcClassForIntMin(length, qcThresholdsMinLength);
 }
 
 static char *qcClassForIntMax(int n, int thresholds[])
 /* Return {qcExcellent, qcGood, qcMeh, qcBad or qcFail} depending on how n compares to the
  * thresholds. Don't free result. */
 {
 if (n <= thresholds[0])
     return "qcExcellent";
 else if (n <= thresholds[1])
     return "qcGood";
 else if (n <= thresholds[2])
     return "qcMeh";
 else if (n <= thresholds[3])
     return "qcBad";
 else
     return "qcFail";
 }
 
 static char *qcClassForNs(int nCount)
 /* Return qc class for #Ns in sample. */
 {
 return qcClassForIntMax(nCount, qcThresholdsMaxNs);
 }
 
 static char *qcClassForMixed(int mixedCount)
 /* Return qc class for #ambiguous bases in sample. */
 {
 return qcClassForIntMax(mixedCount, qcThresholdsMaxMixed);
 }
 
 static char *qcClassForIndel(int indelCount)
 /* Return qc class for #inserted or deleted bases. */
 {
 return qcClassForIntMax(indelCount, qcThresholdsMaxIndel);
 }
 
 static char *qcClassForSNVs(int snvCount)
 /* Return qc class for #SNVs in sample. */
 {
 return qcClassForIntMax(snvCount, qcThresholdsMaxSNVs);
 }
 
 static char *qcClassForMaskedSNVs(int maskedCount)
 /* Return qc class for #SNVs at problematic sites. */
 {
 return qcClassForIntMax(maskedCount, qcThresholdsMaxMaskedSNVs);
 }
 
 static char *qcClassForImputedBases(int imputedCount)
 /* Return qc class for #ambiguous bases for which UShER imputed values based on placement. */
 {
 return qcClassForIntMax(imputedCount, qcThresholdsMaxImputed);
 }
 
 static char *qcClassForPlacements(int placementCount)
 /* Return qc class for number of equally parsimonious placements. */
 {
 return qcClassForIntMax(placementCount, qcThresholdsMaxPlacements);
 }
 
 static char *qcClassForPScore(int parsimonyScore)
 /* Return qc class for parsimonyScore. */
 {
 return qcClassForIntMax(parsimonyScore, qcThresholdsMaxPScore);
 }
 
 static void printTooltip(char *text)
 /* Print a tooltip with explanatory text. */
 {
 printf(TOOLTIP("%s"), text);
 }
 
 static void appendExcludingNs(struct dyString *dy, struct seqInfo *si)
 /* Append a note to dy about how many N bases and start and/or end are excluded from statistic. */
 {
 dyStringAppend(dy, "excluding ");
 if (si->nCountStart)
     dyStringPrintf(dy, "%d N bases at start", si->nCountStart);
 if (si->nCountStart && si->nCountEnd)
     dyStringAppend(dy, " and ");
 if (si->nCountEnd)
     dyStringPrintf(dy, "%d N bases at end", si->nCountEnd);
 }
 
 static void summarizeSequences(struct seqInfo *seqInfoList, boolean isFasta,
                                struct usherResults *ur, struct tempName *jsonTns[],
                                struct hash *sampleMetadata, struct mutationAnnotatedTree *bigTree,
                                struct dnaSeq *refGenome)
 /* Show a table with composition & alignment stats for each sequence that passed basic QC. */
 {
 if (seqInfoList)
     {
     puts("<table class='seqSummary'>");
     boolean gotClades = FALSE, gotLineages = FALSE;
     lookForCladesAndLineages(seqInfoList, ur->samplePlacements, &gotClades, &gotLineages);
     printSummaryHeader(isFasta, gotClades, gotLineages);
     puts("<tbody>");
     struct dyString *dy = dyStringNew(0);
     struct seqInfo *si;
     for (si = seqInfoList;  si != NULL;  si = si->next)
         {
         puts("<tr>");
         printf("<th>%s</td>", replaceChars(si->seq->name, "|", " | "));
         if (isFasta)
             {
             if (si->nCountStart || si->nCountEnd)
                 {
                 int effectiveLength = si->seq->size - (si->nCountStart + si->nCountEnd);
                 dyStringClear(dy);
                 dyStringPrintf(dy, "%d ", effectiveLength);
                 appendExcludingNs(dy, si);
                 dyStringPrintf(dy, " (original size %d)", si->seq->size);
                 printf("<td class='%s'>%d", qcClassForLength(effectiveLength), effectiveLength);
                 printTooltip(dy->string);
                 printf("</td>");
                 }
             else
                 printf("<td class='%s'>%d</td>", qcClassForLength(si->seq->size), si->seq->size);
             }
         printf("<td class='%s'>%d",
                qcClassForNs(si->nCountMiddle), si->nCountMiddle);
         if (si->nCountStart || si->nCountEnd)
             {
             dyStringClear(dy);
             dyStringPrintf(dy, "%d Ns ", si->nCountMiddle);
             appendExcludingNs(dy, si);
             printTooltip(dy->string);
             }
         printf("</td><td class='%s'>%d ", qcClassForMixed(si->ambigCount), si->ambigCount);
         int alignedAmbigCount = 0;
         if (si->ambigCount > 0)
             {
             dyStringClear(dy);
             struct singleNucChange *snc;
             for (snc = si->sncList;  snc != NULL;  snc = snc->next)
                 {
                 if (isIupacAmbiguous(snc->newBase))
                     {
                     dyStringAppendSep(dy, ", ");
                     dyStringPrintf(dy, "%c%d%c", snc->refBase, snc->chromStart+1, snc->newBase);
                     alignedAmbigCount++;
                     }
                 }
             if (isEmpty(dy->string))
                 dyStringAppend(dy, "(Masked or not aligned to reference)");
             else if (alignedAmbigCount != si->ambigCount)
                 dyStringPrintf(dy, " (%d masked or not aligned to reference)",
                                si->ambigCount - alignedAmbigCount);
             printTooltip(dy->string);
             }
         printf("</td>");
         if (isFasta)
             {
             struct psl *psl = si->psl;
             if (psl)
                 {
                 int aliCount = psl->match + psl->misMatch + psl->repMatch;
                 printf("<td class='%s'>%d ", qcClassForLength(aliCount), aliCount);
                 dyStringClear(dy);
                 dyStringPrintf(dy, "bases %d - %d align to reference bases %d - %d",
                                psl->qStart+1, psl->qEnd, psl->tStart+1, psl->tEnd);
                 printTooltip(dy->string);
                 printf("</td><td class='%s'>%d ",
                        qcClassForIndel(si->insBases), si->insBases);
                 if (si->insBases)
                     {
                     printTooltip(si->insRanges);
                     }
                 printf("</td><td class='%s'>%d ",
                        qcClassForIndel(si->delBases), si->delBases);
                 if (si->delBases)
                     {
                     printTooltip(si->delRanges);
                     }
                 printf("</td>");
                 }
             else
                 printf("<td colspan=3 class='%s'> not alignable </td>",
                        qcClassForLength(0));
             }
         int snvCount = slCount(si->sncList) - alignedAmbigCount;
         printf("<td class='%s'>%d", qcClassForSNVs(snvCount), snvCount);
         if (snvCount > 0)
             {
             dyStringClear(dy);
             struct singleNucChange *snc;
             for (snc = si->sncList;  snc != NULL;  snc = snc->next)
                 {
                 if (!isIupacAmbiguous(snc->newBase))
                     {
                     dyStringAppendSep(dy, ", ");
                     dyStringPrintf(dy, "%c%d%c", snc->refBase, snc->chromStart+1, snc->newBase);
                     }
                 }
             printTooltip(dy->string);
             }
         int maskedCount = slCount(si->maskedSncList);
         printf("</td><td class='%s'>%d", qcClassForMaskedSNVs(maskedCount), maskedCount);
         if (maskedCount > 0)
             {
             dyStringClear(dy);
             struct singleNucChange *snc;
             struct slRef *reasonsRef;
             for (snc = si->maskedSncList, reasonsRef = si->maskedReasonsList;  snc != NULL;
                  snc = snc->next, reasonsRef = reasonsRef->next)
                 {
                 dyStringAppendSep(dy, ", ");
                 struct slName *reasonList = reasonsRef->val, *reason;
                 replaceChar(reasonList->name, '_', ' ');
                 dyStringPrintf(dy, "%c%d%c (%s",
                                snc->refBase, snc->chromStart+1, snc->newBase, reasonList->name);
                 for (reason = reasonList->next;  reason != NULL;  reason = reason->next)
                     {
                     replaceChar(reason->name, '_', ' ');
                     dyStringPrintf(dy, ", %s", reason->name);
                     }
                 dyStringAppendC(dy, ')');
                 }
             printTooltip(dy->string);
             }
         printf("</td>");
         struct placementInfo *pi = hashFindVal(ur->samplePlacements, si->seq->name);
         if (pi)
             {
             if (gotClades)
                 printf("<td>%s</td>", pi->nextClade ? pi->nextClade : "n/a");
             if (gotLineages)
                 printf("<td>%s</td>", pi->pangoLineage ? pi->pangoLineage : "n/a");
             struct slName *neighbor = findNearestNeighbor(bigTree, pi->sampleId, pi->variantPath);
             char *lineage = neighbor ?  lineageForSample(sampleMetadata, neighbor->name) : "?";
             printf("<td>%s</td><td>%s</td>",
                    neighbor ? replaceChars(neighbor->name, "|", " | ") : "?",
                    lineage ? lineage : "?");
             int imputedCount = slCount(pi->imputedBases);
             printf("<td class='%s'>%d",
                    qcClassForImputedBases(imputedCount), imputedCount);
             if (imputedCount > 0)
                 {
                 dyStringClear(dy);
                 struct baseVal *bv;
                 for (bv = pi->imputedBases;  bv != NULL;  bv = bv->next)
                     {
                     dyStringAppendSep(dy, ", ");
                     dyStringPrintf(dy, "%d: %s", bv->chromStart+1, bv->val);
                     }
                 printTooltip(dy->string);
                 }
             printf("</td><td class='%s'>%d",
                    qcClassForPlacements(pi->bestNodeCount), pi->bestNodeCount);
             printf("</td><td class='%s'>%d",
                    qcClassForPScore(pi->parsimonyScore), pi->parsimonyScore);
             printf("</td>");
             }
         else
             {
             if (gotClades)
                 printf("<td>n/a></td>");
             if (gotLineages)
                 printf("<td>n/a></td>");
             printf("<td>n/a</td><td>n/a</td><td>n/a</td><td>n/a</td><td>n/a</td>");
             }
         int ix;
         struct subtreeInfo *ti = subtreeInfoForSample(ur->subtreeInfoList, si->seq->name, &ix);
         if (ix < 0)
             //#*** Probably an error.
             printf("<td>n/a</td>");
         else
             {
             printf("<td>%d", ix+1);
             if (ti && nextstrainHost())
                 {
                 char *nextstrainUrl = nextstrainUrlFromTn(jsonTns[ix]);
                 printf(" (<a href='%s' target=_blank>view in Nextstrain<a>)", nextstrainUrl);
                 }
             printf("</td>");
             }
         puts("</tr>");
         }
     puts("</tbody></table><p></p>");
     }
 }
 
 static struct singleNucChange *sncListFromSampleMutsAndImputed(struct slName *sampleMuts,
                                                                struct baseVal *imputedBases)
 /* Convert a list of "<ref><pos><alt>" names to struct singleNucChange list.
  * However, if <alt> is ambiguous, skip it because variantProjector doesn't like it.
  * Add imputed base predictions. */
 {
 struct singleNucChange *sncList = NULL;
 struct slName *mut;
 for (mut = sampleMuts;  mut != NULL;  mut = mut->next)
     {
     char ref = mut->name[0];
     if (ref < 'A' || ref > 'Z')
         errAbort("sncListFromSampleMuts: expected ref base value, got '%c' in '%s'",
                  ref, mut->name);
     int pos = atoi(&(mut->name[1]));
     if (pos < 1 || pos > chromSize)
         errAbort("sncListFromSampleMuts: expected pos between 1 and %d, got %d in '%s'",
                  chromSize, pos, mut->name);
     char alt = mut->name[strlen(mut->name)-1];
     if (alt < 'A' || alt > 'Z')
         errAbort("sncListFromSampleMuts: expected alt base value, got '%c' in '%s'",
                  alt, mut->name);
     if (isIupacAmbiguous(alt))
         continue;
     struct singleNucChange *snc;
     AllocVar(snc);
     snc->chromStart = pos-1;
     snc->refBase = ref;
     snc->newBase = alt;
     slAddHead(&sncList, snc);
     }
 struct baseVal *bv;
 for (bv = imputedBases;  bv != NULL;  bv = bv->next)
     {
     struct singleNucChange *snc;
     AllocVar(snc);
     snc->chromStart = bv->chromStart;
     snc->refBase = '?';
     snc->newBase = bv->val[0];
     slAddHead(&sncList, snc);
     }
 slReverse(&sncList);
 return sncList;
 }
 
 struct aaMutInfo
 // A protein change, who has it, and how important we think it is.
 {
     char *name;                 // The name that people are used to seeing, e.g. "E484K', "N501Y"
     struct slName *sampleIds;   // The uploaded samples that have it
     int priority;               // For sorting; lower number means scarier.
     int pos;                    // 1-based position
     char oldAa;                 // Reference AA
     char newAa;                 // Alt AA
 };
 
 int aaMutInfoCmp(const void *a, const void *b)
 /* Compare aaMutInfo priority for sorting. */
 {
 const struct aaMutInfo *amiA = *(struct aaMutInfo * const *)a;
 const struct aaMutInfo *amiB = *(struct aaMutInfo * const *)b;
 return amiA->priority - amiB->priority;
 }
 
 // For now, hardcode SARS-CoV-2 Spike RBD coords and antibody escape positions (1-based).
 static int rbdStart = 319;
 static int rbdEnd = 541;
 static boolean *escapeMutPos = NULL;
 
 static void initEscapeMutPos()
 /* Allocate excapeMutPos and set positions implicated by at least a couple experiments from Bloom Lab
  * or that appear in Whelan, Rappuoli or McCoy tracks. */
 {
 AllocArray(escapeMutPos, rbdEnd);
 escapeMutPos[332] = TRUE;
 escapeMutPos[334] = TRUE;
 escapeMutPos[335] = TRUE;
 escapeMutPos[337] = TRUE;
 escapeMutPos[339] = TRUE;
 escapeMutPos[340] = TRUE;
 escapeMutPos[345] = TRUE;
 escapeMutPos[346] = TRUE;
 escapeMutPos[348] = TRUE;
 escapeMutPos[352] = TRUE;
 escapeMutPos[357] = TRUE;
 escapeMutPos[359] = TRUE;
 escapeMutPos[361] = TRUE;
 escapeMutPos[362] = TRUE;
 escapeMutPos[363] = TRUE;
 escapeMutPos[365] = TRUE;
 escapeMutPos[366] = TRUE;
 escapeMutPos[367] = TRUE;
 escapeMutPos[369] = TRUE;
 escapeMutPos[370] = TRUE;
 escapeMutPos[371] = TRUE;
 escapeMutPos[372] = TRUE;
 escapeMutPos[373] = TRUE;
 escapeMutPos[374] = TRUE;
 escapeMutPos[376] = TRUE;
 escapeMutPos[378] = TRUE;
 escapeMutPos[383] = TRUE;
 escapeMutPos[384] = TRUE;
 escapeMutPos[385] = TRUE;
 escapeMutPos[386] = TRUE;
 escapeMutPos[408] = TRUE;
 escapeMutPos[417] = TRUE;
 escapeMutPos[441] = TRUE;
 escapeMutPos[444] = TRUE;
 escapeMutPos[445] = TRUE;
 escapeMutPos[445] = TRUE;
 escapeMutPos[447] = TRUE;
 escapeMutPos[449] = TRUE;
 escapeMutPos[450] = TRUE;
 escapeMutPos[452] = TRUE;
 escapeMutPos[455] = TRUE;
 escapeMutPos[456] = TRUE;
 escapeMutPos[458] = TRUE;
 escapeMutPos[472] = TRUE;
 escapeMutPos[473] = TRUE;
 escapeMutPos[474] = TRUE;
 escapeMutPos[476] = TRUE;
 escapeMutPos[477] = TRUE;
 escapeMutPos[478] = TRUE;
 escapeMutPos[479] = TRUE;
 escapeMutPos[483] = TRUE;
 escapeMutPos[484] = TRUE;
 escapeMutPos[485] = TRUE;
 escapeMutPos[486] = TRUE;
 escapeMutPos[487] = TRUE;
 escapeMutPos[489] = TRUE;
 escapeMutPos[490] = TRUE;
 escapeMutPos[494] = TRUE;
 escapeMutPos[499] = TRUE;
 escapeMutPos[504] = TRUE;
 escapeMutPos[514] = TRUE;
 escapeMutPos[517] = TRUE;
 escapeMutPos[522] = TRUE;
 escapeMutPos[525] = TRUE;
 escapeMutPos[526] = TRUE;
 escapeMutPos[527] = TRUE;
 escapeMutPos[528] = TRUE;
 escapeMutPos[529] = TRUE;
 escapeMutPos[530] = TRUE;
 escapeMutPos[531] = TRUE;
 }
 
 static int spikePriority(int pos, char newAa)
 /* Lower number for scarier spike mutation, per spike mutations track / RBD. */
 {
 if (escapeMutPos == NULL)
     initEscapeMutPos();
 int priority = 0;
 if (pos >= rbdStart && pos <= rbdEnd)
     {
     // Receptor binding domain
     priority = 100;
     // Antibody escape mutation in Variant of Concern/Interest
     if (pos == 484)
         priority = 10;
     else if (pos == 501)
         priority = 15;
     else if (pos == 452)
         priority = 20;
     // Other antibody escape mutations
     else if (pos == 439 || pos == 477)
         priority = 25;
     else if (escapeMutPos[pos])
         priority = 50;
     }
 else if (pos >= 675 && pos <= 681)
     // Furin cleavage site; circumstantial evidence for Q677{H,P} spread in US.
     // Interesting threads on SPHERES 2021-02-26 about P681H tradeoff between infectivity vs
     // range of cell types that can be infected and other observations about that region.
     priority = 110;
 else if (pos == 614 && newAa == 'G')
     // Old hat
     priority = 1000;
 else
     // Somewhere else in Spike
     priority = 500;
 return priority;
 }
 
 static void addSpikeChange(struct hash *spikeChanges, char *aaMutStr, char *sampleId)
 /* Tally up an observance of a S gene change in a sample. */
 {
 // Parse oldAa, pos, newAA out of aaMutStr.  Need a more elegant way of doing this;
 // this is a rush job to get something usable out there asap.
 char oldAa = aaMutStr[0];
 int pos = atoi(aaMutStr+1);
 char newAa = aaMutStr[strlen(aaMutStr)-1];
 struct hashEl *hel = hashLookup(spikeChanges, aaMutStr);
 if (hel == NULL)
     {
     struct aaMutInfo *ami;
     AllocVar(ami);
     ami->name = cloneString(aaMutStr);
     slNameAddHead(&ami->sampleIds, sampleId);
     ami->priority = spikePriority(pos, newAa);
     ami->pos = pos;
     ami->oldAa = oldAa;
     ami->newAa = newAa;
     hashAdd(spikeChanges, aaMutStr, ami);
     }
 else
     {
     struct aaMutInfo *ami = hel->val;
     slNameAddHead(&ami->sampleIds, sampleId);
     }
 }
 
 static void writeOneTsvRow(FILE *f, char *sampleId, struct usherResults *results,
                            struct hash *seqInfoHash, struct geneInfo *geneInfoList,
                            struct seqWindow *gSeqWin, struct hash *spikeChanges)
 /* Write one row of tab-separate summary for sampleId.  Accumulate S gene AA change info. */
 {
 struct placementInfo *info = hashFindVal(results->samplePlacements, sampleId);
 if (info)
     {
     // sample name / ID
     fprintf(f, "%s\t", sampleId);
     // nucleotide mutations
     struct slName *mut;
     for (mut = info->sampleMuts;  mut != NULL;  mut = mut->next)
         {
         if (mut != info->sampleMuts)
             fputc(',', f);
         fputs(mut->name, f);
         }
     fputc('\t', f);
     // AA mutations
     struct singleNucChange *sncList = sncListFromSampleMutsAndImputed(info->sampleMuts,
                                                                       info->imputedBases);
     struct slPair *geneAaMutations = getAaMutations(sncList, geneInfoList, gSeqWin);
     struct slPair *geneAaMut;
     boolean first = TRUE;
     for (geneAaMut = geneAaMutations;  geneAaMut != NULL;  geneAaMut = geneAaMut->next)
         {
         struct slName *aaMut;
         for (aaMut = geneAaMut->val;  aaMut != NULL;  aaMut = aaMut->next)
             {
             if (first)
                 first = FALSE;
             else
                 fputc(',', f);
             fprintf(f, "%s:%s", geneAaMut->name, aaMut->name);
             if (sameString(geneAaMut->name, "S"))
                 addSpikeChange(spikeChanges, aaMut->name, sampleId);
             }
         }
     fputc('\t', f);
     // imputed bases (if any)
     struct baseVal *bv;
     for (bv = info->imputedBases;  bv != NULL;  bv = bv->next)
         {
         if (bv != info->imputedBases)
             fputc(',', f);
         fprintf(f, "%d%s", bv->chromStart+1, bv->val);
         }
     fputc('\t', f);
     // path through tree to sample
     printVariantPathNoNodeNames(f, info->variantPath);
     // number of equally parsimonious placements
     fprintf(f, "\t%d", info->bestNodeCount);
     // parsimony score
     fprintf(f, "\t%d", info->parsimonyScore);
     struct seqInfo *si = hashFindVal(seqInfoHash, sampleId);
     if (si)
         {
         if (si->psl)
             {
             // length
             fprintf(f, "\t%d", si->seq->size);
             struct psl *psl = si->psl;
             // aligned bases, indel counts & ranges
             int aliCount = psl->match + psl->misMatch + psl->repMatch;
             fprintf(f, "\t%d\t%d\t%s\t%d\t%s",
                     aliCount, si->insBases, emptyForNull(si->insRanges),
                     si->delBases, emptyForNull(si->delRanges));
             }
         else
             fprintf(f, "\tn/a\tn/a\tn/a\tn/a\tn/a\tn/a");
         // SNVs that were masked (Problematic Sites track), not used in placement
         fputc('\t', f);
         struct singleNucChange *snc;
         for (snc = si->maskedSncList;  snc != NULL;  snc = snc->next)
             {
             if (snc != si->maskedSncList)
                 fputc(',', f);
             fprintf(f, "%c%d%c", snc->refBase, snc->chromStart+1, snc->newBase);
             }
         }
     else
         {
         warn("writeOneTsvRow: no sequenceInfo for sample '%s'", sampleId);
         fprintf(f, "\tn/a\tn/a\tn/a\tn/a\tn/a\tn/a\tn/a");
         }
     fputc('\n', f);
     }
 }
 
 static void rWriteTsvSummaryTreeOrder(struct phyloTree *node, FILE *f, struct usherResults *results,
                                       struct hash *seqInfoHash, struct geneInfo *geneInfoList,
                                       struct seqWindow *gSeqWin, struct hash *spikeChanges)
 /* As we encounter leaves (user-uploaded samples) in depth-first search order, write out a line
  * of TSV summary for each one. */
 {
 if (node->numEdges)
     {
     int i;
     for (i = 0;  i < node->numEdges;  i++)
         rWriteTsvSummaryTreeOrder(node->edges[i], f, results, seqInfoHash, geneInfoList, gSeqWin,
                                   spikeChanges);
     }
 else
     {
     writeOneTsvRow(f, node->ident->name, results, seqInfoHash, geneInfoList, gSeqWin, spikeChanges);
     }
 }
 
 
 static struct hash *hashFromSeqInfoList(struct seqInfo *seqInfoList)
 /* Hash sequence name to seqInfo for quick lookup. */
 {
 struct hash *hash = hashNew(0);
 struct seqInfo *si;
 for (si = seqInfoList;  si != NULL;  si = si->next)
     hashAdd(hash, si->seq->name, si);
 return hash;
 }
 
 static struct tempName *writeTsvSummary(struct usherResults *results, struct phyloTree *sampleTree,
                                         struct slName *sampleIds, struct seqInfo *seqInfoList,
                                         struct geneInfo *geneInfoList, struct seqWindow *gSeqWin,
                                         struct hash *spikeChanges, int *pStartTime)
 /* Write a tab-separated summary file for download.  If the user uploaded enough samples to make
  * a tree, then write out samples in tree order; otherwise use sampleIds list.
  * Accumulate S gene changes. */
 {
 struct tempName *tsvTn = NULL;
 AllocVar(tsvTn);
 trashDirFile(tsvTn, "ct", "usher_samples", ".tsv");
 FILE *f = mustOpen(tsvTn->forCgi, "w");
 fprintf(f, "name\tnuc_mutations\taa_mutations\timputed_bases\tmutation_path"
         "\tplacement_count\tparsimony_score_increase\tlength\taligned_bases"
         "\tins_bases\tins_ranges\tdel_bases\tdel_ranges\tmasked_mutations"
         "\n");
 struct hash *seqInfoHash = hashFromSeqInfoList(seqInfoList);
 if (sampleTree)
     {
     rWriteTsvSummaryTreeOrder(sampleTree, f, results, seqInfoHash, geneInfoList, gSeqWin,
                               spikeChanges);
     }
 else
     {
     struct slName *sample;
     for (sample = sampleIds;  sample != NULL;  sample = sample->next)
         writeOneTsvRow(f, sample->name, results, seqInfoHash, geneInfoList, gSeqWin, spikeChanges);
     }
 carefulClose(&f);
 hashFree(&seqInfoHash);
 reportTiming(pStartTime, "write tsv summary");
 return tsvTn;
 }
 
 static struct tempName *writeSpikeChangeSummary(struct hash *spikeChanges, int totalSampleCount)
 /* Write a tab-separated summary of S (Spike) gene changes for download. */
 {
 struct tempName *tsvTn = NULL;
 AllocVar(tsvTn);
 trashDirFile(tsvTn, "ct", "usher_S_muts", ".tsv");
 FILE *f = mustOpen(tsvTn->forCgi, "w");
 fprintf(f, "aa_mutation\tsample_count\tsample_frequency\tsample_ids"
         "\n");
 struct aaMutInfo *sChanges[spikeChanges->elCount];
 struct hashCookie cookie = hashFirst(spikeChanges);
 int ix = 0;
 struct hashEl *hel;
 while ((hel = hashNext(&cookie)) != NULL)
     {
     if (ix >= spikeChanges->elCount)
         errAbort("writeSpikeChangeSummary: hash elCount is %d but got more elements",
                  spikeChanges->elCount);
     sChanges[ix++] = hel->val;
     }
 if (ix != spikeChanges->elCount)
     errAbort("writeSpikeChangeSummary: hash elCount is %d but got fewer elements (%d)",
              spikeChanges->elCount, ix);
 qsort(sChanges, ix, sizeof(sChanges[0]), aaMutInfoCmp);
 for (ix = 0;  ix < spikeChanges->elCount;  ix++)
     {
     struct aaMutInfo *ami = sChanges[ix];
     int sampleCount = slCount(ami->sampleIds);
     fprintf(f, "S:%s\t%d\t%f",
             ami->name, sampleCount, (double)sampleCount / (double)totalSampleCount);
     slReverse(&ami->sampleIds);
     fprintf(f, "\t%s", ami->sampleIds->name);
     struct slName *sample;
     for (sample = ami->sampleIds->next;  sample != NULL;  sample = sample->next)
         fprintf(f, ",%s", sample->name);
     fputc('\n', f);
     }
 carefulClose(&f);
 return tsvTn;
 }
 
 static struct tempName *makeSubtreeZipFile(struct usherResults *results, struct tempName *jsonTns[],
                                            struct tempName *singleSubtreeJsonTn, int *pStartTime)
 /* Make a zip archive file containing all of the little subtree Newick and JSON files so
  * user doesn't have to click on each one. */
 {
 struct tempName *zipTn;
 AllocVar(zipTn);
 trashDirFile(zipTn, "ct", "usher_subtrees", ".zip");
 int subtreeCount = slCount(results->subtreeInfoList);
 char *cmd[10 + 2*(subtreeCount+1)];
 char **cmds[] = { cmd, NULL };
 int cIx = 0, sIx = 0;
 cmd[cIx++] = "zip";
 cmd[cIx++] = "-j";
 cmd[cIx++] = zipTn->forCgi;
 cmd[cIx++] = singleSubtreeJsonTn->forCgi;
 cmd[cIx++] = results->singleSubtreeInfo->subtreeTn->forCgi;
 struct subtreeInfo *ti;
 for (ti = results->subtreeInfoList;  ti != NULL;  ti = ti->next, sIx++)
     {
     cmd[cIx++] = jsonTns[sIx]->forCgi;
     cmd[cIx++] = ti->subtreeTn->forCgi;
     }
 cmd[cIx++] = NULL;
 struct pipeline *pl = pipelineOpen(cmds, pipelineRead, NULL, NULL);
 pipelineClose(&pl);
 reportTiming(pStartTime, "make subtree zipfile");
 return zipTn;
 }
 
 static struct slName **getProblematicSites(char *db)
 /* If config.ra specfies maskFile them return array of lists (usually NULL) of reasons that
  * masking is recommended, one per position in genome; otherwise return NULL. */
 {
 struct slName **pSites = NULL;
 char *pSitesFile = phyloPlaceDbSettingPath(db, "maskFile");
 if (isNotEmpty(pSitesFile) && fileExists(pSitesFile))
     {
     AllocArray(pSites, chromSize);
     struct bbiFile *bbi = bigBedFileOpen(pSitesFile);
     struct lm *lm = lmInit(0);
     struct bigBedInterval *bb, *bbList = bigBedIntervalQuery(bbi, chrom, 0, chromSize, 0, lm);
     for (bb = bbList;  bb != NULL;  bb = bb->next)
         {
         char *extra = bb->rest;
         char *reason = nextWord(&extra);
         int i;
         for (i = bb->start;  i < bb->end;  i++)
             slNameAddHead(&pSites[i], reason);
         }
     bigBedFileClose(&bbi);
     }
 return pSites;
 }
 
 static void downloadsRow(char *treeFile, char *sampleSummaryFile, char *spikeSummaryFile,
                          char *subtreeZipFile)
 /* Make a row of quick download file links, to appear between the button row & big summary table. */
 {
 printf("<p><b>Downloads:</b> | ");
 printf("<a href='%s' download>Global phylogenetic tree with your sequences</a> | ", treeFile);
 printf("<a href='%s' download>TSV summary of sequences and placements</a> | ", sampleSummaryFile);
 printf("<a href='%s' download>TSV summary of Spike mutations</a> | ", spikeSummaryFile);
 printf("<a href='%s' download>ZIP file of subtree JSON and Newick files</a> | ", subtreeZipFile);
 puts("</p>");
 }
 
 static int subTreeInfoUserSampleCmp(const void *pa, const void *pb)
 /* Compare subtreeInfo by number of user sample IDs (highest number first). */
 {
 struct subtreeInfo *tiA = *(struct subtreeInfo **)pa;
 struct subtreeInfo *tiB = *(struct subtreeInfo **)pb;
 return slCount(tiB->subtreeUserSampleIds) - slCount(tiA->subtreeUserSampleIds);
 }
 
 char *phyloPlaceSamples(struct lineFile *lf, char *db, char *defaultProtobuf,
                         boolean doMeasureTiming, int subtreeSize, int fontHeight)
 /* Given a lineFile that contains either FASTA or VCF, prepare VCF for usher;
  * if that goes well then run usher, report results, make custom track files
  * and return the top-level custom track file; otherwise return NULL. */
 {
 char *ctFile = NULL;
 measureTiming = doMeasureTiming;
 int startTime = clock1000();
 struct tempName *vcfTn = NULL;
 struct slName *sampleIds = NULL;
 char *usherPath = getUsherPath(TRUE);
 char *usherAssignmentsPath = NULL;
 char *source = NULL;
 char *metadataFile = NULL;
 struct treeChoices *treeChoices = loadTreeChoices(db);
 if (treeChoices)
     {
     usherAssignmentsPath = defaultProtobuf;
     if (isEmpty(usherAssignmentsPath))
         usherAssignmentsPath = treeChoices->protobufFiles[0];
     int i;
     for (i = 0;  i < treeChoices->count;  i++)
         if (sameString(treeChoices->protobufFiles[i], usherAssignmentsPath))
             {
             metadataFile = treeChoices->metadataFiles[i];
             source = treeChoices->sources[i];
             break;
             }
     if (i == treeChoices->count)
         {
         usherAssignmentsPath = treeChoices->protobufFiles[0];
         metadataFile = treeChoices->metadataFiles[0];
         source = treeChoices->sources[0];
         }
     }
 else
     {
     // Fall back on old settings
     usherAssignmentsPath = getUsherAssignmentsPath(db, TRUE);
     metadataFile = phyloPlaceDbSettingPath(db, "metadataFile");
     source = "GISAID";
     }
 struct mutationAnnotatedTree *bigTree = parseParsimonyProtobuf(usherAssignmentsPath);
 reportTiming(&startTime, "parse protobuf file");
 if (! bigTree)
     {
     warn("Problem parsing %s; can't make subtree subtracks.", usherAssignmentsPath);
     }
 lineFileCarefulNewlines(lf);
 struct slName **maskSites = getProblematicSites(db);
 struct dnaSeq *refGenome = hChromSeq(db, chrom, 0, chromSize);
 boolean isFasta = FALSE;
 struct seqInfo *seqInfoList = NULL;
 if (lfLooksLikeFasta(lf))
     {
     boolean *informativeBases = informativeBasesFromTree(bigTree->tree, maskSites);
     struct slPair *failedSeqs;
     struct slPair *failedPsls;
     vcfTn = vcfFromFasta(lf, db, refGenome, informativeBases, maskSites,
                          &sampleIds, &seqInfoList, &failedSeqs, &failedPsls, &startTime);
     if (failedSeqs)
         {
         puts("<p>");
         struct slPair *fail;
         for (fail = failedSeqs;  fail != NULL;  fail = fail->next)
             printf("%s<br>\n", fail->name);
         puts("</p>");
         }
     if (failedPsls)
         {
         puts("<p>");
         struct slPair *fail;
         for (fail = failedPsls;  fail != NULL;  fail = fail->next)
             printf("%s<br>\n", fail->name);
         puts("</p>");
         }
     if (seqInfoList == NULL)
         printf("<p>Sorry, could not align any sequences to reference well enough to place in "
                "the phylogenetic tree.</p>\n");
     isFasta = TRUE;
     }
 else if (lfLooksLikeVcf(lf))
     {
     vcfTn = checkAndSaveVcf(lf, refGenome, maskSites, &seqInfoList, &sampleIds);
     reportTiming(&startTime, "check uploaded VCF");
     }
 else
     {
     if (isNotEmpty(lf->fileName))
         warn("Sorry, can't recognize your file %s as FASTA or VCF.\n", lf->fileName);
     else
         warn("Sorry, can't recognize your uploaded data as FASTA or VCF.\n");
     }
 lineFileClose(&lf);
 if (vcfTn)
     {
     fflush(stdout);
     int seqCount = slCount(seqInfoList);
     // Don't make smaller subtrees when a large number of sequences are uploaded.
     if (seqCount > MAX_SEQ_DETAILS)
         subtreeSize = 0;
     struct usherResults *results = runUsher(usherPath, usherAssignmentsPath, vcfTn->forCgi,
                                             subtreeSize, sampleIds, bigTree->condensedNodes,
                                             &startTime);
     if (results->singleSubtreeInfo)
         {
+        puts("<p></p>");
         readQcThresholds(db);
         int subtreeCount = slCount(results->subtreeInfoList);
         // Sort subtrees by number of user samples (largest first).
         slSort(&results->subtreeInfoList, subTreeInfoUserSampleCmp);
         // Make Nextstrain/auspice JSON file for each subtree.
         char *bigGenePredFile = phyloPlaceDbSettingPath(db, "bigGenePredFile");
         struct geneInfo *geneInfoList = getGeneInfoList(bigGenePredFile, refGenome);
         struct seqWindow *gSeqWin = chromSeqWindowNew(db, chrom, 0, chromSize);
         struct hash *sampleMetadata = getSampleMetadata(metadataFile);
-        struct tempName *singleSubtreeJsonTn;
-        AllocVar(singleSubtreeJsonTn);
-        trashDirFile(singleSubtreeJsonTn, "ct", "singleSubtreeAuspice", ".json");
-        treeToAuspiceJson(results->singleSubtreeInfo, db, geneInfoList, gSeqWin, sampleMetadata,
-                          singleSubtreeJsonTn->forCgi, source);
+        struct hash *sampleUrls = hashNew(0);
         struct tempName *jsonTns[subtreeCount];
         struct subtreeInfo *ti;
         int ix;
         for (ix = 0, ti = results->subtreeInfoList;  ti != NULL;  ti = ti->next, ix++)
             {
             AllocVar(jsonTns[ix]);
             char subtreeName[512];
             safef(subtreeName, sizeof(subtreeName), "subtreeAuspice%d", ix+1);
             trashDirFile(jsonTns[ix], "ct", subtreeName, ".json");
-            treeToAuspiceJson(ti, db, geneInfoList, gSeqWin, sampleMetadata, jsonTns[ix]->forCgi,
-                              source);
+            treeToAuspiceJson(ti, db, geneInfoList, gSeqWin, sampleMetadata, NULL,
+                              jsonTns[ix]->forCgi, source);
+            // Add a link for every sample to this subtree, so the single-subtree JSON can
+            // link to subtree JSONs
+            char *subtreeUrl = nextstrainUrlFromTn(jsonTns[ix]);
+            struct slName *sample;
+            for (sample = ti->subtreeUserSampleIds;  sample != NULL;  sample = sample->next)
+                hashAdd(sampleUrls, sample->name, subtreeUrl);
             }
-        puts("<p></p>");
+        struct tempName *singleSubtreeJsonTn;
+        AllocVar(singleSubtreeJsonTn);
+        trashDirFile(singleSubtreeJsonTn, "ct", "singleSubtreeAuspice", ".json");
+        treeToAuspiceJson(results->singleSubtreeInfo, db, geneInfoList, gSeqWin, sampleMetadata,
+                          sampleUrls, singleSubtreeJsonTn->forCgi, source);
         struct subtreeInfo *subtreeInfoForButtons = results->subtreeInfoList;
         if (seqCount > MAX_SEQ_DETAILS || subtreeCount > MAX_SUBTREE_BUTTONS)
             subtreeInfoForButtons = NULL;
         makeButtonRow(singleSubtreeJsonTn, jsonTns, subtreeInfoForButtons, subtreeSize, isFasta);
         printf("<p>If you have metadata you wish to display, click a 'view subtree in "
                "Nextstrain' button, and then you can drag on a CSV file to "
                "<a href='"NEXTSTRAIN_DRAG_DROP_DOC"' target=_blank>add it to the tree view</a>."
                "</p>\n");
 
         // Make custom tracks for uploaded samples and subtree(s).
         struct phyloTree *sampleTree = NULL;
         struct tempName *ctTn = writeCustomTracks(vcfTn, results, sampleIds, bigTree->tree,
                                                   source, fontHeight, &sampleTree, &startTime);
 
         // Make a sample summary TSV file and accumulate S gene changes
         struct hash *spikeChanges = hashNew(0);
         struct tempName *tsvTn = writeTsvSummary(results, sampleTree, sampleIds, seqInfoList,
                                                  geneInfoList, gSeqWin, spikeChanges, &startTime);
         struct tempName *sTsvTn = writeSpikeChangeSummary(spikeChanges, slCount(sampleIds));
         struct tempName *zipTn = makeSubtreeZipFile(results, jsonTns, singleSubtreeJsonTn,
                                                     &startTime);
         downloadsRow(results->bigTreePlusTn->forHtml, tsvTn->forHtml, sTsvTn->forHtml,
                      zipTn->forHtml);
 
         if (seqCount <= MAX_SEQ_DETAILS)
             {
             summarizeSequences(seqInfoList, isFasta, results, jsonTns, sampleMetadata, bigTree,
                                refGenome);
             reportTiming(&startTime, "write summary table (including reading in lineages)");
             for (ix = 0, ti = results->subtreeInfoList;  ti != NULL;  ti = ti->next, ix++)
                 {
                 int subtreeUserSampleCount = slCount(ti->subtreeUserSampleIds);
                 printf("<h3>Subtree %d: ", ix+1);
                 if (subtreeUserSampleCount > 1)
                     printf("%d related samples", subtreeUserSampleCount);
                 else if (subtreeCount > 1)
                     printf("Unrelated sample");
                 printf("</h3>\n");
                 makeNextstrainButtonN("viewNextstrainSub", ix, subtreeUserSampleCount, subtreeSize,
                                       jsonTns);
                 puts("<br>");
                 // Make a sub-subtree with only user samples for display:
                 struct phyloTree *subtree = phyloOpenTree(ti->subtreeTn->forCgi);
                 subtree = phyloPruneToIds(subtree, ti->subtreeUserSampleIds);
                 describeSamplePlacements(ti->subtreeUserSampleIds, results->samplePlacements,
                                          subtree, sampleMetadata, bigTree, source);
                 }
             reportTiming(&startTime, "describe placements");
             }
         else
             printf("<p>(Skipping details and subtrees; "
                    "you uploaded %d sequences, and details/subtrees are shown only when "
                    "you upload at most %d sequences.)</p>\n",
                    seqCount, MAX_SEQ_DETAILS);
 
         // Offer big tree w/new samples for download
         puts("<h3>Downloads</h3>");
         puts("<ul>");
         printf("<li><a href='%s' download>SARS-CoV-2 phylogenetic tree "
                "with your samples (Newick file)</a>\n", results->bigTreePlusTn->forHtml);
         printf("<li><a href='%s' download>TSV summary of sequences and placements</a>\n",
                tsvTn->forHtml);
         printf("<li><a href='%s' download>TSV summary of S (Spike) gene changes</a>\n",
                sTsvTn->forHtml);
         printf("<li><a href='%s' download>ZIP archive of subtree Newick and JSON files</a>\n",
                zipTn->forHtml);
         // For now, leave in the individual links so I don't break anybody's pipeline that's
         // scraping this page...
         for (ix = 0, ti = results->subtreeInfoList;  ti != NULL;  ti = ti->next, ix++)
             {
             int subtreeUserSampleCount = slCount(ti->subtreeUserSampleIds);
             printf("<li><a href='%s' download>Subtree with %s", ti->subtreeTn->forHtml,
                    ti->subtreeUserSampleIds->name);
             if (subtreeUserSampleCount > 10)
                 printf(" and %d other samples", subtreeUserSampleCount - 1);
             else
                 {
                 struct slName *sln;
                 for (sln = ti->subtreeUserSampleIds->next;  sln != NULL;  sln = sln->next)
                     printf(", %s", sln->name);
                 }
             puts(" (Newick file)</a>");
             printf("<li><a href='%s' download>Auspice JSON for subtree with %s",
                    jsonTns[ix]->forHtml, ti->subtreeUserSampleIds->name);
             if (subtreeUserSampleCount > 10)
                 printf(" and %d other samples", subtreeUserSampleCount - 1);
             else
                 {
                 struct slName *sln;
                 for (sln = ti->subtreeUserSampleIds->next;  sln != NULL;  sln = sln->next)
                     printf(", %s", sln->name);
                 }
             puts(" (JSON file)</a>");
             }
         puts("</ul>");
 
         // Notify in opposite order of custom track creation.
         puts("<h3>Custom tracks for viewing in the Genome Browser</h3>");
         printf("<p>Added custom track of uploaded samples.</p>\n");
         if (subtreeCount > 0 && subtreeCount <= MAX_SUBTREE_CTS)
             printf("<p>Added %d subtree custom track%s.</p>\n",
                    subtreeCount, (subtreeCount > 1 ? "s" : ""));
         ctFile = urlFromTn(ctTn);
         }
     else
         {
         warn("No subtree output from usher.\n");
         }
     }
 return ctFile;
 }