/**
 * 运输计划单据（入库单 / 送货单 / 分装单）PDF 截图共用渲染策略。
 * html2canvas 对 0.3px 边框与 border-collapse 在 Windows DPI 缩放下易画成粗线。
 */

/** 固定像素倍率，不跟 devicePixelRatio，保证 Mac / Windows 栅格化尺度一致 */
export function getPlSlipPdfCanvasScale(): number {
  return 3
}

/**
 * 将表格单元格边框改为「仅右+底」的 1px 背景线（首行补顶、首列补左）。
 * 相邻格只画一条共享边，避免全边框叠成双线。
 */
export function applyPdfStableTableCellBorders(cells: Iterable<Element>): void {
  const cellList = Array.from(cells) as HTMLElement[]
  if (!cellList.length) return

  const rows = new Map<HTMLTableRowElement, HTMLElement[]>()
  for (const cell of cellList) {
    const tr = cell.closest('tr')
    if (!tr) continue
    const list = rows.get(tr)
    if (list) list.push(cell)
    else rows.set(tr, [cell])
  }

  let rowIndex = 0
  for (const [, rowCells] of rows) {
    rowCells.forEach((cell, colIndex) => {
      const gradients = ['linear-gradient(#000,#000)', 'linear-gradient(#000,#000)']
      const sizes = ['100% 1px', '1px 100%']
      const positions = ['left bottom', 'right top']

      if (rowIndex === 0) {
        gradients.push('linear-gradient(#000,#000)')
        sizes.push('100% 1px')
        positions.push('left top')
      }
      if (colIndex === 0) {
        gradients.push('linear-gradient(#000,#000)')
        sizes.push('1px 100%')
        positions.push('left top')
      }

      cell.style.setProperty('border', 'none', 'important')
      cell.style.setProperty('border-width', '0', 'important')
      cell.style.setProperty('background-color', '#ffffff', 'important')
      cell.style.setProperty('background-image', gradients.join(','), 'important')
      cell.style.setProperty('background-size', sizes.join(','), 'important')
      cell.style.setProperty('background-position', positions.join(','), 'important')
      cell.style.setProperty('background-repeat', 'no-repeat', 'important')
    })
    rowIndex += 1
  }
}