Feat(home): over time tag spending comparison

src/libs/data_processing.js

@@ -29,8 +29,48 @@ export function formatDate (row, field = 'Date') {
   row[field] = moment(row[field], 'DD/MM/YYYY', true)
 }
 
-export function total (row, field = 'Montant') {
-  var sum = row.map(x => parseFloat(x[field]))
+export function total (rows, field = 'Montant') {
+  var sum = rows.map(x => parseFloat(x[field]))
     .reduce((sum, x) => sum + x, 0)
   return Math.round(sum)
 }
+
+export function tag_filter (rows, tags, invert=false) {
+  // filter rows by tags
+  // invert inverts the selection
+  return rows.filter(row => {
+    if (invert) {
+      return tags.some(t => {
+        return row.tags.map(t => t.name.toLowerCase())
+          .indexOf(t.toLowerCase()) < 0
+      })
+    } else {
+      return tags.every(t => {
+        return row.tags.map(t => t.name.toLowerCase())
+          .indexOf(t.toLowerCase()) > -1
+      })
+    }
+  })
+}
+
+function objectMap (object, mapFn) {
+  // map a function on object value
+  return Object.keys(object).reduce(function(result, key) {
+    result[key] = mapFn(object[key])
+    return result
+  }, {})
+}
+
+export function groupBy (rows, grouping, agg) {
+  // Group rows by field then apply agg
+  var groups = rows.reduce((stock, row) => {
+    var group = grouping(row)
+    if (stock[group]) {
+      stock[group].push(row)
+    } else {
+      stock[group] = [row]
+    }
+    return stock
+  }, {})
+  return objectMap(groups, group => agg(group))
+}