Plops editor: focus mode, place/move/resize, semantic zoom (#15)

Co-authored-by: Steve Dudenhoeffer <[email protected]>

web/src/lib/plantings.test.ts

@@ -0,0 +1,27 @@
+import { describe, expect, it } from 'vitest'
+import { computeDerivedCount, effectiveCount } from './plantings'
+
+describe('computeDerivedCount', () => {
+  it('mirrors the server formula max(1, round(π·r²/spacing²))', () => {
+    expect(computeDerivedCount(10, 10)).toBe(3) // π·100/100 = 3.14 → 3
+    expect(computeDerivedCount(50, 10)).toBe(79) // π·2500/100 = 78.5 → 79
+    expect(computeDerivedCount(30, 15)).toBe(13) // π·900/225 = 12.57 → 13
+  })
+
+  it('floors at 1 for tiny / non-positive inputs', () => {
+    expect(computeDerivedCount(0.1, 10)).toBe(1)
+    expect(computeDerivedCount(0, 10)).toBe(1)
+    expect(computeDerivedCount(10, 0)).toBe(1)
+  })
+
+  it('caps like the server', () => {
+    expect(computeDerivedCount(10_000, 0.1)).toBe(1_000_000)
+  })
+})
+
+describe('effectiveCount', () => {
+  it('prefers the override, else the derived value', () => {
+    expect(effectiveCount({ count: 12, derivedCount: 79 })).toBe(12)
+    expect(effectiveCount({ count: null, derivedCount: 79 })).toBe(79)
+  })
+})