/**
 * 与 NativeTemplateCommandBuilder.toMillimeter 一致（px 按 96dpi 转 mm），
 * 用于判断模板是否适合走 native-fast-printer 的 TSC 模板指令（常见标签幅宽约 4 英寸级）。
 */
import type { SystemLabelTemplate } from './types/printer'

const DESIGN_DPI = 96

/** 常见 4″ 标签机安全上限（mm），略放宽 */
const NATIVE_FAST_MAX_WIDTH_MM = 112
const NATIVE_FAST_MAX_HEIGHT_MM = 320

export function templateSizeToMillimeters (
  unit: string | undefined,
  width: number,
  height: number
): { widthMm: number; heightMm: number } {
  const u = String(unit || 'inch').toLowerCase()
  let widthMm = 0
  let heightMm = 0
  if (u === 'mm') {
    widthMm = width
    heightMm = height
  } else if (u === 'cm') {
    widthMm = width * 10
    heightMm = height * 10
  } else if (u === 'px') {
    widthMm = (width / DESIGN_DPI) * 25.4
    heightMm = (height / DESIGN_DPI) * 25.4
  } else {
    widthMm = width * 25.4
    heightMm = height * 25.4
  }
  return { widthMm, heightMm }
}

export function isTemplateWithinNativeFastPrintBounds (
  template: Pick<SystemLabelTemplate, 'unit' | 'width' | 'height'>
): boolean {
  const w = Number(template.width) || 0
  const h = Number(template.height) || 0
  if (w <= 0 || h <= 0) return false
  const { widthMm, heightMm } = templateSizeToMillimeters(template.unit, w, h)
  return widthMm <= NATIVE_FAST_MAX_WIDTH_MM && heightMm <= NATIVE_FAST_MAX_HEIGHT_MM
}