import assert from 'node:assert/strict'
import {
  IMAGE_PREVIEW_ZOOM_MIN,
  IMAGE_PREVIEW_ZOOM_MAX,
  IMAGE_PREVIEW_ZOOM_STEP,
  clampPreviewZoom,
  computeFitBaseScale,
  buildPreviewTransformCss
} from '../src/utils/image-preview-transform.js'

assert.equal(IMAGE_PREVIEW_ZOOM_MIN, 0.5)
assert.equal(IMAGE_PREVIEW_ZOOM_MAX, 5)
assert.equal(IMAGE_PREVIEW_ZOOM_STEP, 0.15)

assert.equal(clampPreviewZoom(0.1), 0.5)
assert.equal(clampPreviewZoom(9), 5)
assert.equal(clampPreviewZoom(1.234), 1.23)

// 未旋转：640x400 装入 320x200 → scale = 0.5
assert.ok(
  Math.abs(computeFitBaseScale(640, 400, 0, 320, 200) - 0.5) < 1e-9
)

// 旋转 90°：外接 400x640 装入 320x200 → scale = min(320/400, 200/640) = 0.3125
assert.ok(
  Math.abs(computeFitBaseScale(640, 400, 90, 320, 200) - 0.3125) < 1e-9
)

assert.equal(
  buildPreviewTransformCss(10, -20, 90, 0.5),
  'translate(10px, -20px) rotate(90deg) scale(0.5)'
)

console.log('image-preview-transform ok')