taxon distance

src/utils/calcTaxonDistance.js

@@ -0,0 +1,39 @@
+static calcTaxonomicDistance(taxonDistance, targetSpecies, measuredSpecies) {
+    let distance = null;
+
+    targetSpecies = targetSpecies.toLowerCase();
+    measuredSpecies = measuredSpecies.toLowerCase();
+    taxonDistance = Object.assign({}, taxonDistance);
+    for (const key in taxonDistance) {
+      taxonDistance[key.toLowerCase()] = taxonDistance[key];
+    }
+
+    if (
+      targetSpecies === measuredSpecies ||
+      measuredSpecies.startsWith(targetSpecies)
+    ) {
+      distance = 0;
+    } else if (
+      targetSpecies + "_canon_ancestors" in taxonDistance &&
+      measuredSpecies + "_canon_ancestors" in taxonDistance
+    ) {
+      const toAncestors = taxonDistance[targetSpecies + "_canon_ancestors"];
+      const fromAncestors = taxonDistance[measuredSpecies + "_canon_ancestors"];
+      toAncestors.push(targetSpecies);
+      fromAncestors.push(measuredSpecies);
+      distance = 0;
+      for (
+        let iLineage = 0;
+        iLineage < Math.min(toAncestors.length, fromAncestors.length);
+        iLineage++
+      ) {
+        if (toAncestors[iLineage] !== fromAncestors[iLineage]) {
+          distance = toAncestors.length - iLineage;
+          break;
+        }
+      }
+      toAncestors.pop();
+      fromAncestors.pop();
+    } else {
+      distance = null;
+    }