fix doc weight to show real doc instead of forcing 35-51 range and also fixed bug target weight using total days as reference for target weight instead of doc weight

utils/__tests__/weight.test.ts

@@ -0,0 +1,43 @@
+import { describe, expect, it } from 'vitest';
+import { weightStandardData } from '../../mockData/weightStandardData.ts';
+import { getTargetGainForAge, getTargetWeightForAge } from '../weight.ts';
+
+function rowForDoc(docWeight: number) {
+  return weightStandardData.data.find((row) => row.day === docWeight)!;
+}
+
+describe('getTargetWeightForAge', () => {
+  it('uses the exact DOC-weight row and age column', () => {
+    const row = rowForDoc(42);
+    expect(getTargetWeightForAge(1, 42)).toBe(row.values[0]);
+    expect(getTargetWeightForAge(35, 42)).toBe(row.values[34]);
+  });
+
+  it('clamps below-range DOC weight to the 35 g row', () => {
+    const row = rowForDoc(35);
+    expect(getTargetWeightForAge(7, 20)).toBe(row.values[6]);
+    expect(getTargetWeightForAge(7, 30)).toBe(row.values[6]);
+  });
+
+  it('clamps above-range DOC weight to the 51 g row', () => {
+    const row = rowForDoc(51);
+    expect(getTargetWeightForAge(7, 52)).toBe(row.values[6]);
+    expect(getTargetWeightForAge(7, 60)).toBe(row.values[6]);
+  });
+
+  it('returns null for ages outside 1..35', () => {
+    expect(getTargetWeightForAge(0, 42)).toBeNull();
+    expect(getTargetWeightForAge(36, 42)).toBeNull();
+  });
+});
+
+describe('getTargetGainForAge', () => {
+  it('returns day-over-day delta from the DOC-weight row', () => {
+    const row = rowForDoc(40);
+    expect(getTargetGainForAge(2, 40)).toBe(row.values[1]! - row.values[0]!);
+  });
+
+  it('returns null for age 1', () => {
+    expect(getTargetGainForAge(1, 40)).toBeNull();
+  });
+});