feat: enable custom baseline periods for Experiments to solve seasonality

test-calc-es.js

@@ -0,0 +1,83 @@
+import fs from 'fs';
+
+const experiment = {
+    start_date: "2026-01-18",
+    end_date: null,
+    asins: ["LINE:LEGENDS"],
+    marketplace: "ES"
+};
+
+const salesData = [
+    { year: 2026, week: 7, asin: "B0CHW338VR", line: "LEGENDS", unitsTotal: 4, salesTotal: 24.40, marketplace: "ES" },
+    { year: 2026, week: 7, asin: "B0CHW338VR", line: "LEGENDS", unitsTotal: 4, salesTotal: 24.40, marketplace: "GB" }
+];
+
+const getExperimentAsins = (experimentAsins, salesData) => {
+  const explicitAsins = new Set();
+  const lines = new Set();
+
+  (experimentAsins || []).forEach(a => {
+    const val = (a || '').trim().toUpperCase();
+    if (val.startsWith('LINE:')) {
+      lines.add(val.substring(5).trim());
+    } else if (val) {
+      explicitAsins.add(val);
+    }
+  });
+
+  const asinSet = new Set(explicitAsins);
+  if (lines.size > 0 && salesData) {
+    salesData.forEach(r => {
+      const line = (r.line || '').trim().toUpperCase();
+      if (line && lines.has(line)) {
+        if (r.asin) asinSet.add(r.asin.toUpperCase());
+      }
+    });
+  }
+
+  return asinSet;
+};
+
+const parseLocalDate = (dateStr) => {
+    if (!dateStr) return new Date();
+    const [y, m, d] = dateStr.split('T')[0].split('-');
+    return new Date(Number(y), Number(m) - 1, Number(d));
+};
+
+
+const calculate = (experiment, salesData) => {
+  const startDate = parseLocalDate(experiment.start_date);
+  const endDate = experiment.end_date ? parseLocalDate(experiment.end_date) : new Date();
+
+  console.log('Parsed start date:', startDate);
+  console.log('Parsed end date:', endDate);
+
+  const durationMs = endDate.getTime() - startDate.getTime();
+  const baselineStart = new Date(startDate.getTime() - durationMs);
+  const baselineEnd = startDate;
+
+  console.log('Parsed baseline start:', baselineStart);
+  console.log('Parsed baseline end:', baselineEnd);
+
+  const asinSet = getExperimentAsins(experiment.asins, salesData);
+  console.log('Resolved ASINs:', Array.from(asinSet));
+
+  const baselineData = salesData.filter(r => {
+    const recordDate = new Date(r.year, 0, 1 + (r.week - 1) * 7);
+    const inRange = recordDate >= baselineStart && recordDate < baselineEnd;
+    const isAsin = asinSet.has(r.asin.toUpperCase());
+    return isAsin && inRange && (experiment.marketplace === 'All' || r.marketplace === experiment.marketplace);
+  });
+
+  const experimentData = salesData.filter(r => {
+    const recordDate = new Date(r.year, 0, 1 + (r.week - 1) * 7);
+    const inRange = recordDate >= startDate && recordDate <= endDate;
+    const isAsin = asinSet.has(r.asin.toUpperCase());
+    return isAsin && inRange && (experiment.marketplace === 'All' || r.marketplace === experiment.marketplace);
+  });
+
+  console.log('Baseline records matched:', baselineData.length);
+  console.log('Experiment records matched:', experimentData.length);
+};
+
+calculate(experiment, salesData);