CategoryOverpassFilter: allow multiple values, e.g. checkbox (combine by 'or')

src/CategoryOverpassFilter.js

@@ -154,14 +154,18 @@ class CategoryOverpassFilter {
 
   applyParam (param) {
     this.additionalFilter = Object.keys(param).map(k => {
-      let value = param[k]
+      let values = param[k]
+      let d = this.data[k]
 
-      if (value === null) {
+      if (values === null) {
         return null
       }
 
-      var d = this.data[k]
+      if (!Array.isArray(values)) {
+        values = [ values ]
+      }
 
+      let ret = values.map(value => {
         if ('values' in d && value in d.values && typeof d.values[value] === 'object' && 'query' in d.values[value]) {
           let f = new Filter(d.values[value].query)
           return f.def
@@ -208,6 +212,16 @@ class CategoryOverpassFilter {
         return [ v ]
       }).filter(f => f) // remove null values
 
+      switch (ret.length) {
+        case 0:
+          return null
+        case 1:
+          return ret[0]
+        default:
+          return { or: ret }
+      }
+    }).filter(f => f) // remove null values
+
     if (this.additionalFilter.length === 0) {
       this.additionalFilter = []
     } else if (this.additionalFilter.length === 1) {