refac: cleaning round for image cropping/resizing

web/src/lib/__tests__/imageCrop.spec.ts

@@ -1,11 +1,16 @@
 import { describe, expect, it } from 'vitest'
 import {
+	clampRect,
 	computeOutputSize,
 	estimateOutputBytes,
 	formatEstimatedSize,
+	moveRect,
+	ratioValueFor,
 	rectForRatio,
+	resizeRect,
 	rotateRectBySteps,
 	rotatedDimensions,
+	widthPresetPixels,
 	wholeRect,
 } from '../imageCrop'
 
@@ -41,6 +46,122 @@ describe('estimateOutputBytes', () => {
 	})
 })
 
+describe('formatEstimatedSize', () => {
+	it('stays in KB just under the 1000 KB threshold', () => {
+		expect(formatEstimatedSize(999 * 1024)).toBe('999 KB')
+	})
+
+	it('switches to MB at and above the 1000 KB threshold', () => {
+		expect(formatEstimatedSize(1024 * 1024 * 2.5)).toBe('2.5 MB')
+	})
+})
+
+describe('clampRect', () => {
+	it('rounds fractional coordinates and dimensions to whole pixels', () => {
+		expect(clampRect({ x: 100.2, y: 50.7, width: 200.4, height: 150.6 }, 4032, 3024)).toEqual({
+			x: 100,
+			y: 51,
+			width: 200,
+			height: 151,
+		})
+	})
+
+	it('clamps width and height to the bounds', () => {
+		expect(clampRect({ x: 0, y: 0, width: 5000, height: 4000 }, 4032, 3024)).toEqual({
+			x: 0,
+			y: 0,
+			width: 4032,
+			height: 3024,
+		})
+	})
+
+	it('clamps x and y so the rect stays inside the bounds', () => {
+		expect(clampRect({ x: 4000, y: 3000, width: 3024, height: 3024 }, 4032, 3024)).toEqual({
+			x: 1008,
+			y: 0,
+			width: 3024,
+			height: 3024,
+		})
+	})
+
+	it('never lets width or height drop below 1px', () => {
+		expect(clampRect({ x: 0, y: 0, width: -10, height: 0 }, 4032, 3024)).toEqual({
+			x: 0,
+			y: 0,
+			width: 1,
+			height: 1,
+		})
+	})
+})
+
+describe('moveRect', () => {
+	it('offsets the rect and clamps it inside the bounds', () => {
+		const rect = { x: 100, y: 100, width: 200, height: 200 }
+		expect(moveRect(rect, 50, -50, 4032, 3024)).toEqual({
+			x: 150,
+			y: 50,
+			width: 200,
+			height: 200,
+		})
+	})
+
+	it('stops at the bound edge instead of moving past it', () => {
+		const rect = { x: 0, y: 0, width: 200, height: 200 }
+		expect(moveRect(rect, -50, -50, 4032, 3024)).toEqual({
+			x: 0,
+			y: 0,
+			width: 200,
+			height: 200,
+		})
+	})
+})
+
+describe('resizeRect', () => {
+	it('grows freely on both axes when no ratio is locked', () => {
+		const rect = { x: 0, y: 0, width: 200, height: 200 }
+		expect(resizeRect(rect, 20, 10, 4032, 3024, null)).toEqual({
+			x: 0,
+			y: 0,
+			width: 220,
+			height: 210,
+		})
+	})
+
+	it('derives height from width when a ratio is locked and width changes', () => {
+		const rect = { x: 0, y: 0, width: 200, height: 200 }
+		expect(resizeRect(rect, 100, 0, 4032, 3024, 16 / 9)).toEqual({
+			x: 0,
+			y: 0,
+			width: 300,
+			height: 169,
+		})
+	})
+})
+
+describe('ratioValueFor', () => {
+	it('returns null for Free so the frame is unconstrained', () => {
+		expect(ratioValueFor('Free', 4032, 3024)).toBeNull()
+	})
+
+	it('derives Original from the current bounds', () => {
+		expect(ratioValueFor('Original', 4032, 3024)).toBeCloseTo(4032 / 3024)
+	})
+
+	it('returns the fixed value for a named ratio', () => {
+		expect(ratioValueFor('1:1', 4032, 3024)).toBe(1)
+	})
+})
+
+describe('widthPresetPixels', () => {
+	it('returns null for Original so the crop keeps its own width', () => {
+		expect(widthPresetPixels('Original')).toBeNull()
+	})
+
+	it('returns the pixel target for a fixed preset', () => {
+		expect(widthPresetPixels('800 px')).toBe(800)
+	})
+})
+
 describe('rotateRectBySteps', () => {
 	it('rotates a whole-image rect 90deg clockwise into the new bounds', () => {
 		const rotated = rotateRectBySteps(wholeRect(4032, 3024), 4032, 3024, 1)