// 导出页面为PDF格式
import html2canvas from 'html2canvas'
import JSPDF from 'jspdf'

export function ExportSavePdf(htmlTitle, currentTime) {
  var element = document.getElementById('pdfCentent')
  html2canvas(element, {
    logging: false
  }).then(function(canvas) {
    var pdf = new JSPDF('l', 'mm', '[241,279.4]') //自定义页面大小
    var ctx = canvas.getContext('2d')
    var a4w = 236; var a4h = 274.4 // 纸张大小，241mm x 279.4mm
    var imgHeight = Math.floor(a4h * canvas.width / a4w) // 按A4显示比例换算一页图像的像素高度
    var renderedHeight = 0

    while (renderedHeight < canvas.height) {
      var page = document.createElement('canvas')
      page.width = canvas.width
      page.height = Math.min(imgHeight, canvas.height - renderedHeight)// 可能内容不足一页

      // 用getImageData剪裁指定区域，并画到前面创建的canvas对象中
      page.getContext('2d').putImageData(ctx.getImageData(0, renderedHeight, canvas.width, Math.min(imgHeight, canvas.height - renderedHeight)), 0, 0)
      pdf.addImage(page.toDataURL('image/jpeg', 1.0), 'JPEG', 10, 10, a4w, Math.min(a4h, a4w * page.height / page.width)) // 添加图像到页面，保留10mm边距

      renderedHeight += imgHeight
      if (renderedHeight < canvas.height) { pdf.addPage() }// 如果后面还有内容，添加一个空页
      // delete page;
    }
    pdf.save(htmlTitle + currentTime)
  })
}