import assert from 'node:assert/strict'
import test from 'node:test'
import type { FieldResult } from '../src/types'
import { getOverlayRect, getScrollTarget, getTargetZoom } from '../src/components/pdfPreviewMath'

const field: FieldResult = {
  id: 'field-1',
  page: 1,
  text: '食品名称：天问礼品粽',
  font_name: 'Mock Font',
  font_size_pt: 12,
  font_height_mm: 4,
  x0_pt: 100,
  top_pt: 80,
  x1_pt: 180,
  bottom_pt: 116,
  normalized_text: '食品名称天问礼品粽',
  validation_status: 'matched',
  validation_reason: 'matched',
  matched_excerpt: '食品名称：天问礼品粽',
}

test('getOverlayRect keeps tiny fields visible without drifting away from center', () => {
  const rect = getOverlayRect(
    {
      ...field,
      x1_pt: 101,
      bottom_pt: 81,
    },
    0.4,
    0.4,
  )

  assert.equal(rect.width, 4)
  assert.equal(rect.height, 4)
  assert.equal(rect.strokeWidth, 1)
  assert.equal(rect.left, 38.2)
  assert.equal(rect.top, 30.2)
})

test('getTargetZoom caps focus zoom and keeps normal fit as the floor', () => {
  assert.equal(
    getTargetZoom(field, { width: 1200, height: 900 }, 0.5),
    2.8,
  )

  assert.equal(
    getTargetZoom(field, { width: 0, height: 900 }, 0.5),
    1,
  )
})

test('getScrollTarget centers the active field and clamps to scroll bounds', () => {
  const rect = getOverlayRect(field, 2, 2)
  const centered = getScrollTarget({
    containerWidth: 800,
    containerHeight: 600,
    scrollWidth: 2200,
    scrollHeight: 1800,
    pageOffsetLeft: 260,
    pageOffsetTop: 420,
    rect,
  })

  assert.deepEqual(centered, {
    left: 140,
    top: 316,
  })

  const clamped = getScrollTarget({
    containerWidth: 800,
    containerHeight: 600,
    scrollWidth: 1200,
    scrollHeight: 900,
    pageOffsetLeft: 20,
    pageOffsetTop: 30,
    rect,
  })

  assert.deepEqual(clamped, {
    left: 0,
    top: 0,
  })
})