taro2canvas/src/index.js

将 Taro 指定节点转换成 canvas 元素

import Taro from '@tarojs/taro';

import { IMAGE_MODE } from './constants';
import { getUid, noop, transferBorder, transferBoxShadow, transferPadding } from './utils';

export default class Taro2Canvas {
  constructor(options = {}) {
    this.device = Taro.getSystemInfoSync() || {};
    this.zoom = options.zoom || this.device.windowWidth / 375;

    this.element = options.element;
    this.obj = options.obj;
    this.width = Math.floor(options.width * this.zoom) || 0;
    this.height = Math.floor(options.height * this.zoom) || 0;
    this.destZoom = options.destZoom || 3;
    this.destWidth = Math.floor(this.width * this.destZoom) || 0;
    this.destHeight = Math.floor(this.height * this.destZoom) || 0;
    this.translateX = options.translateX * this.zoom || 0;
    this.translateY = options.translateY * this.zoom || 0;
    this.gradientBackground = options.gradientBackground || null;
    this.background = options.background || '#ffffff';
    this.finishDraw = options.finish || noop;
    this.errorHandler = options.error || noop;
    this.progress = options.progress || noop;
    this.textAlign = options.textAlign || 'left';
    this.fullText = options.fullText || false;
    this.font = options.font || '14px PingFang SC';

    this._init();
  }

  draw(data = {}, that) {
    let self = this;
    this.data = data;
    this.fef = that;

    this.progress(10);
    this._preloadImage(data.list)
      .then(result => {
        this.progress(30);
        self._draw();
      })
      .catch(res => {
        self.errorHandler(res);
      });
  }

  measureWidth(text, font) {
    if (font) {
      this.ctx.font = font;
    }
    let res = this.ctx.measureText(text) || {};
    return res.width || 0;
  }

  _init() {
    this.progressPercent = 0; // 绘制进度百分比
    this.data = null;
    this.ref = null;
    this.allPic = [];
    this.screenList = [];
    this.asyncList = [];
    this.imgUrl = '';
    this.progressPercent = 0;
    this.distance = 0;
    this.progress(0);

    this.ctx = Taro.createCanvasContext(this.element, this.obj);
    this.ctx.font = this.font;
    this.ctx.setTextBaseline('top');
    this.ctx.setStrokeStyle('white');

    this.debug = this.device.platform === 'devtools';

    this._drawBakcground();
  }

  _drawBakcground() {
    if (this.gradientBackground) {
      let line = this.gradientBackground.line || [0, 0, 0, this.height];
      let color = this.gradientBackground.color || ['#fff', '#fff'];
      let style = { fill: { line, color } };
      this._drawRectToCanvas(0, 0, this.width, this.height, style);
    } else {
      let style = { fill: this.background };
      this._drawRectToCanvas(0, 0, this.width, this.height, style);
    }
  }

  _draw() {
    let self = this;
    let list = this.data.list || [];
    let index = 0;
    let all = [];
    let count = 0;

    list.forEach(item => {
      if (item.type === 'wxml') {
        count += 3;
      } else {
        count += 1;
      }
    });

    this.distance = 60 / (count || 1); // 进度条的间距
    this.progressPercent = 30;
    this.asyncList = list.filter(item => item.delay == true);
    list = list.filter(item => item.delay != true);
    drawList(list);

    Promise.all(all)
      .then(results => {
        index = 0;
        drawList(self.asyncList, true);

        Promise.all(all).then(results => {
          self.progress(90);
          self._saveCanvasToImage();
        });
      })
      .catch(e => {
        console.log(e);
        self.errorHandler(e);
      });

    function drawList(list = [], noDelay) {
      list.forEach((item, i) => {
        all[index++] = new Promise((resolve, reject) => {
          let attr = item.style;
          item.progress = self.distance;
          if (noDelay) {
            item.delay = 0;
          }
          if (item.type === 'radius-image') {
            self._drawCircle(item, attr, resolve, reject, 'image');
          } else if (item.type === 'text') {
            self._drawText(item, attr, resolve, reject);
          } else if (item.type === 'line') {
            self._drawLine(item, attr, resolve, reject);
          } else if (item.type === 'circle') {
            self._drawCircle(item, attr, resolve, reject);
          } else if (item.type === 'rect') {
            self._drawRect(item, attr, resolve, reject);
          } else if (item.type === 'image') {
            self._drawRect(item, attr, resolve, reject, 'image');
          } else if (item.type === 'wxml') {
            self._drawWxml(item, attr, resolve, reject);
          } else {
            resolve();
          }
        });
      });
    }
  }

  _saveCanvasToImage() {
    let self = this;

    // 延时保存有两个原因，一个是等待绘制delay的元素，另一个是安卓上样式会错乱
    setTimeout(
      () => {
        self.progress(95);

        let obj = {
          x: 0,
          y: 0,
          width: self.width,
          height: self.height,
          canvasId: self.element,
          success: function(res) {
            self.progress(100);
            self.imgUrl = res.tempFilePath;
            self.finishDraw(self.imgUrl);
          },
          fail: function(res) {
            self.errorHandler({ errcode: 1000, errmsg: 'save canvas error', e: res });
          },
        };

        if (self.destZoom !== 3) {
          obj.destWidth = self.destWidth;
          obj.destHeight = self.destHeight;
        }

        Taro.canvasToTempFilePath(obj, self.obj);
      },
      self.device.system.indexOf('iOS') === -1 ? 300 : 100
    );
  }

  _preloadImage(list = []) {
    let self = this;
    let all = [];
    let count = 0;

    list.forEach((item, i) => {
      if (item.url && self._findPicIndex(item.url) === -1) {
        // 避免重复下载同一图片
        self.allPic.push({
          url: item.url,
          local: '',
        });
        all[count++] = new Promise((resolve, reject) => {
          // 非http(s)域名的就不下载了
          if (
            !/^http/.test(item.url) ||
            /^http:\/\/(tmp)|(usr)\//.test(item.url) ||
            /^http:\/\/127\.0\.0\.1/.test(item.url)
          ) {
            if (item.isBase64) {
              let fileManager = Taro.getFileSystemManager();

              fileManager.writeFile({
                filePath: item.url,
                data: item.isBase64.replace(/data:image\/(.*);base64,/, ''),
                encoding: 'base64',
                success(res) {
                  imageInfo(item.url);
                },
                fail(res) {
                  reject(res);
                },
              });
            } else {
              imageInfo(item.url);
            }

            function imageInfo(url) {
              Taro.getImageInfo({
                src: url,
                success(res) {
                  let index = self._findPicIndex(url);
                  if (index > -1) {
                    self.allPic[index].local = url;
                    self.allPic[index].width = res.width;
                    self.allPic[index].height = res.height;
                  }
                  resolve({ tempFilePath: url });
                },
                fail(res) {
                  reject(res);
                },
              });
            }
          } else {
            Taro.downloadFile({
              url: item.url.replace(/^https?/, 'https'),
              success: function(res) {
                Taro.getImageInfo({
                  src: res.tempFilePath,
                  success(img) {
                    let index = self._findPicIndex(item.url);
                    if (index > -1) {
                      self.allPic[index].local = res.tempFilePath;
                      self.allPic[index].width = img.width;
                      self.allPic[index].height = img.height;
                    }
                    resolve(res);
                  },
                  fail(res) {
                    reject(res);
                  },
                });
              },
              fail: res => {
                reject({ errcode: 1001, errmsg: 'download pic error' });
              },
            });
          }
        });
      }
    });

    return Promise.all(all)
      .then(results => {
        return new Promise(resolve => {
          resolve();
        });
      })
      .catch(results => {
        return new Promise((resolve, reject) => {
          reject(results);
        });
      });
  }

  _findPicIndex(url) {
    let index = this.allPic.findIndex(pic => pic.url === url);
    return index;
  }

  _drawRect(item, style, resolve, reject, isImage, isWxml) {
    let zoom = this.zoom;
    let leftOffset = 0;
    let topOffset = 0;
    let width = style.width;
    let height = style.height;
    let imgWidth = style.width;
    let imgHeight = style.height;
    let mode = null;

    try {
      item.x = this._resetPositionX(item, style);
      item.y = this._resetPositionY(item, style);

      let url;
      if (isImage) {
        let index = this._findPicIndex(item.url);
        if (index > -1) {
          url = this.allPic[index].local;
          imgWidth = this.allPic[index].width;
          imgHeight = this.allPic[index].height;
        } else {
          url = item.url;
        }
      }

      style.padding = style.padding || [];
      if (isWxml === 'inline-wxml') {
        item.x = item.x + ((style.padding[3] && style.padding[3]) || 0);
        item.y = item.y + ((style.padding[0] && style.padding[0]) || 0);
      }

      leftOffset = item.x + style.width + ((style.padding[1] && style.padding[1]) || 0);

      if (!isWxml) {
        width = width * zoom;
        height = height * zoom;
      }

      if (style.dataset && style.dataset.mode && IMAGE_MODE.indexOf(style.dataset.mode) > -1) {
        mode = {
          type: style.dataset.mode,
          width: imgWidth,
          height: imgHeight,
        };
      }

      this._drawRectToCanvas(item.x, item.y, width, height, style, url, mode);
      this._updateProgress(item.progress);

      if (resolve) {
        resolve();
      } else {
        return {
          leftOffset,
          topOffset,
        };
      }
    } catch (e) {
      reject && reject({ errcode: isImage ? 1003 : 1002, errmsg: isImage ? 'drawImage error' : 'drawRect error', e });
    }
  }

  _drawRectToCanvas(x, y, width, height, style, url, mode) {
    let { fill, border, boxShadow } = style;
    this.ctx.save();
    this._drawBoxShadow(boxShadow, res => {
      // 真机上填充渐变色时，没有阴影，先画个相等大小的纯色矩形来实现阴影
      if (fill && typeof fill !== 'string' && !this.debug) {
        this.ctx.setFillStyle(res.color || '#ffffff');
        this.ctx.fillRect(x, y, width, height);
      }
    });

    if (url) {
      // 开发者工具有bug，先不裁剪
      if (mode) {
        this._resetImageByMode(url, x, y, width, height, mode);
      } else {
        this.ctx.drawImage(url, x, y, width, height);
      }
    } else {
      this._setFill(fill, () => {
        this.ctx.fillRect(x, y, width, height);
      });
    }

    this._drawBorder(border, style, border => {
      let fixBorder = border.width;
      this.ctx.strokeRect(x - fixBorder / 2, y - fixBorder / 2, width + fixBorder, height + fixBorder);
    });

    this.ctx.draw(true);
    this.ctx.restore();
  }

  _resetImageByMode(url, x, y, width, height, mode) {
    let self = this;
    let offsetX = 0;
    let offsetY = 0;
    let imgWidth = mode.width;
    let imgHeight = mode.height;

    switch (mode.type) {
      case 'scaleToFill':
        imgWidth = width;
        imgHeight = height;
        self.ctx.drawImage(url, x, y, width, height);
        break;
      case 'widthFix':
        height = width / ((imgWidth || 1) / (imgHeight || 1));
        self.ctx.drawImage(url, x, y, width, height);
        break;
      case 'aspectFit':
        if (imgWidth > imgHeight) {
          let realHeight = width / ((imgWidth || 1) / (imgHeight || 1));
          offsetY = -(height - realHeight) / 2;
          imgWidth = width;
          imgHeight = realHeight;
        } else {
          let realWidth = height / ((imgHeight || 1) / (imgWidth || 1));
          offsetX = -(width - realWidth) / 2;
          imgWidth = realWidth;
          imgHeight = height;
        }

        _clip();
        break;
      case 'aspectFill':
        if (imgWidth > imgHeight) {
          let realWidth = imgWidth / ((imgHeight || 1) / (height || 1));
          offsetX = (realWidth - width) / 2;
          imgWidth = realWidth;
          imgHeight = height;
        } else {
          let realHeight = imgHeight / ((imgWidth || 1) / (width || 1));
          offsetY = (realHeight - height) / 2;
          imgWidth = width;
          imgHeight = realHeight;
        }

        _clip();
        break;
      case 'top left':
        _clip();
        break;
      case 'top':
        offsetX = (mode.width - width) / 2;
        _clip();
        break;
      case 'top right':
        offsetX = mode.width - width;
        _clip();
        break;
      case 'left':
        offsetY = (mode.height - height) / 2;
        _clip();
        break;
      case 'center':
        offsetX = (mode.width - width) / 2;
        offsetY = (mode.height - height) / 2;
        _clip();
        break;
      case 'right':
        offsetX = mode.width - width;
        offsetY = (mode.height - height) / 2;
        _clip();
        break;
      case 'bottom left':
        offsetY = mode.height - height;
        _clip();
        break;
      case 'bottom':
        offsetX = (mode.width - width) / 2;
        offsetY = mode.height - height;
        _clip();
        break;
      case 'bottom right':
        offsetX = mode.width - width;
        offsetY = mode.height - height;
        _clip();
        break;
      default:
        imgWidth = width;
        imgHeight = height;
        break;
    }

    function _clip() {
      self.ctx.save();
      self.ctx.beginPath();
      self.ctx.rect(x, y, width, height);
      self.ctx.clip();
      self.ctx.drawImage(url, x - offsetX, y - offsetY, imgWidth, imgHeight);
      self.ctx.closePath();
      self.ctx.restore();
    }
  }

  _drawText(item, style, resolve, reject, type, isWxml) {
    let zoom = this.zoom;
    let leftOffset = 0;
    let topOffset = 0;

    try {
      style.fontSize = this._parseNumber(style.fontSize);
      let fontSize = Math.ceil((style.fontSize || 14) * zoom);
      this.ctx.setTextBaseline('top');
      this.ctx.font = `${style.fontWeight ? style.fontWeight : 'normal'} ${fontSize}px ${style.fontFamily ||
        'PingFang SC'}`;
      this.ctx.setFillStyle(style.color || '#454545');

      let text = item.text || '';
      let textWidth = Math.floor(this.measureWidth(text, style.font || this.ctx.font));
      let lineHeight = this._getLineHeight(style);
      let textHeight = Math.ceil(textWidth / (style.width || textWidth)) * lineHeight;
      let width = Math.ceil((style.width || textWidth) * (!isWxml ? zoom : 1));
      let whiteSpace = style.whiteSpace || 'wrap';
      let x = 0;
      let y = 0;

      if (typeof style.padding === 'string') {
        style.padding = transferPadding(style.padding);
      }
      item.x = this._resetPositionX(item, style);
      item.y = this._resetPositionY(item, style, textHeight);
      this._drawBoxShadow(style.boxShadow);

      if (style.background || style.border) {
        this._drawTextBackgroud(item, style, textWidth, textHeight, isWxml);
      }

      // 行内文本
      if (type === 'inline-text') {
        width = item.maxWidth;
        if (item.leftOffset + textWidth > width) {
          // 如果上一个行内元素换行了，这个元素要继续在后面补足一行
          let lineNum = Math.max(Math.floor(textWidth / width), 1);
          let length = text.length;
          let singleLength = Math.floor(length / lineNum);
          let widthOffset = item.leftOffset ? item.leftOffset - item.originX : 0;
          let { endIndex: currentIndex, single, singleWidth } = this._getTextSingleLine(
            text,
            width,
            singleLength,
            0,
            widthOffset
          );
          x = this._resetTextPositionX(item, style, singleWidth);
          y = this._resetTextPositionY(item, style);
          this.ctx.fillText(single, x, y);
          leftOffset = x + singleWidth;
          topOffset = y;

          // 去除第一行补的内容，然后重置
          text = text.substring(currentIndex, text.length);
          currentIndex = 0;
          lineNum = Math.max(Math.floor(textWidth / width), 1);
          textWidth = Math.floor(this.measureWidth(text, style.font || this.ctx.font));
          item.x = item.originX; // 还原换行后的x
          for (let i = 0; i < lineNum; i++) {
            let { endIndex, single, singleWidth } = this._getTextSingleLine(text, width, singleLength, currentIndex);
            currentIndex = endIndex;
            if (single) {
              x = this._resetTextPositionX(item, style, singleWidth, width);
              y = this._resetTextPositionY(item, style, i + 1);
              this.ctx.fillText(single, x, y);
              if (i === lineNum - 1) {
                leftOffset = x + singleWidth;
                topOffset = lineHeight * lineNum;
              }
            }
          }

          let last = text.substring(currentIndex, length);
          let lastWidth = this.measureWidth(last);

          if (last) {
            x = this._resetTextPositionX(item, style, lastWidth, width);
            y = this._resetTextPositionY(item, style, lineNum + 1);
            this.ctx.fillText(last, x, y);
            leftOffset = x + lastWidth;
            topOffset = lineHeight * (lineNum + 1);
          }
        } else {
          x = this._resetTextPositionX(item, style, textWidth, width);
          y = this._resetTextPositionY(item, style);
          this.ctx.fillText(item.text, x, y);
          leftOffset = x + textWidth;
          topOffset = lineHeight;
        }
      } else {
        // block文本，如果文本长度超过宽度换行
        if (width && textWidth > width && whiteSpace !== 'nowrap') {
          let lineNum = Math.max(Math.floor(textWidth / width), 1);
          let length = text.length;
          let singleLength = Math.floor(length / lineNum);
          let currentIndex = 0;

          // lineClamp参数限制最多行数
          if (style.lineClamp && lineNum + 1 > style.lineClamp) {
            lineNum = style.lineClamp - 1;
          }

          for (let i = 0; i < lineNum; i++) {
            let { endIndex, single, singleWidth } = this._getTextSingleLine(text, width, singleLength, currentIndex);
            currentIndex = endIndex;
            x = this._resetTextPositionX(item, style, singleWidth, width);
            y = this._resetTextPositionY(item, style, i);
            this.ctx.fillText(single, x, y);
          }

          // 换行后剩余的文字，超过一行则截断增加省略号
          let last = text.substring(currentIndex, length);
          let lastWidth = this.measureWidth(last);
          if (lastWidth > width) {
            let { single, singleWidth } = this._getTextSingleLine(last, width, singleLength);
            lastWidth = singleWidth;
            last = single.substring(0, single.length - 1) + '...';
          }

          x = this._resetTextPositionX(item, style, lastWidth, width);
          y = this._resetTextPositionY(item, style, lineNum);
          this.ctx.fillText(last, x, y);
        } else {
          x = this._resetTextPositionX(item, style, textWidth, width);
          y = this._resetTextPositionY(item, style);
          this.ctx.fillText(item.text, x, y);
        }
      }

      this.ctx.draw(true);

      this._updateProgress(item.progress);

      if (resolve) {
        resolve();
      } else {
        return {
          leftOffset,
          topOffset,
        };
      }
    } catch (e) {
      reject && reject({ errcode: 1004, errmsg: 'drawText error', e: e });
    }
  }

  _drawTextBackgroud(item, style, textWidth, textHeight, isWxml) {
    if (!style.width) return;
    let zoom = isWxml ? 1 : this.zoom;
    let width = style.width || textWidth;
    let height = style.height || textHeight;
    let rectStyle = {
      fill: style.background,
      border: style.border,
    };
    style.padding = style.padding || [0, 0, 0, 0];
    width += (style.padding[1] || 0) + (style.padding[3] || 0);
    height += (style.padding[0] || 0) + (style.padding[2] || 0);
    width = width * zoom;
    height = height * zoom;
    this._drawRectToCanvas(item.x, item.y, width, height, rectStyle);
  }

  _drawCircle(item, style, resolve, reject, isImage, isWxml) {
    let zoom = this.zoom;
    let r = style.r;
    try {
      item.x = this._resetPositionX(item, style);
      item.y = this._resetPositionY(item, style);

      let url;
      if (isImage) {
        let index = this._findPicIndex(item.url);
        if (index > -1) {
          url = this.allPic[index].local;
        } else {
          url = item.url;
        }
      }

      if (!isWxml) {
        r = r * zoom;
      }

      this._drawCircleToCanvas(item.x, item.y, r, style, url);

      this._updateProgress(item.progress);
      resolve && resolve();
    } catch (e) {
      reject &&
        reject({ errcode: isImage ? 1006 : 1005, errmsg: isImage ? 'drawCircleImage error' : 'drawCircle error', e });
    }
  }

  _drawCircleToCanvas(x, y, r, style, url) {
    let { fill, border, boxShadow } = style;

    this.ctx.save();

    this._drawBoxShadow(boxShadow, res => {
      // 真机上填充渐变色时，没有阴影，先画个相等大小的纯色矩形来实现阴影
      if ((fill && typeof fill !== 'string') || (url && res.color)) {
        this.ctx.setFillStyle(res.color || '#ffffff');
        this.ctx.beginPath();
        this.ctx.arc(x + r, y + r, r, 0, 2 * Math.PI);
        this.ctx.closePath();
        this.ctx.fill();
      }
    });

    if (url) {
      this.ctx.save();
      this.ctx.beginPath();
      this.ctx.arc(x + r, y + r, r, 0, 2 * Math.PI);
      this.ctx.clip();
      this.ctx.drawImage(url, x, y, r * 2, r * 2);
      this.ctx.closePath();
      this.ctx.restore();
    } else {
      this._setFill(fill, () => {
        this.ctx.beginPath();
        this.ctx.arc(x + r, y + r, r, 0, 2 * Math.PI);
        this.ctx.closePath();
        this.ctx.fill();
      });
    }

    this._drawBorder(border, style, border => {
      this.ctx.beginPath();
      this.ctx.arc(x + r, y + r, r + border.width / 2, 0, 2 * Math.PI);
      this.ctx.stroke();
      this.ctx.closePath();
    });

    this.ctx.draw(true);
    this.ctx.restore();
  }

  _drawLine(item, style, resolve, reject, isWxml) {
    let zoom = this.zoom;
    try {
      let x1 = item.x * zoom + this.translateX;
      let y1 = item.y * zoom + this.translateY;
      let x2 = item.x2 * zoom + this.translateX;
      let y2 = item.y2 * zoom + this.translateY;
      this._drawLineToCanvas(x1, y1, x2, y2, style);

      this._updateProgress(item.progress);
      resolve && resolve();
    } catch (e) {
      reject && reject({ errcode: 1007, errmsg: 'drawLine error', e });
    }
  }

  _drawLineToCanvas(x1, y1, x2, y2, style) {
    let { stroke, dash, boxShadow } = style;

    this.ctx.save();
    if (stroke) {
      this._setStroke(stroke);
    }

    this._drawBoxShadow(boxShadow);

    if (dash) {
      let dash = [style.dash[0] || 5, style.dash[1] || 5];
      let offset = style.dash[2] || 0;
      this.ctx.setLineDash(dash, offset || 0);
    }

    this.ctx.moveTo(x1, y1);
    this.ctx.setLineWidth((style.width || 1) * this.zoom);
    this.ctx.lineTo(x2, y2);
    this.ctx.stroke();
    this.ctx.draw(true);
    this.ctx.restore();
  }

  _drawWxml(item, style, resolve, reject) {
    let self = this;
    let all = [];
    try {
      this._getWxml(item, style).then(results => {
        // 上 -> 下
        let sorted = self._sortListByTop(results[0]);
        let count = 0;
        let progress = 0;
        Object.keys(sorted).forEach(item => {
          count += sorted[item].length;
        });
        progress = (this.distance * 3) / (count || 1);

        all = this._drawWxmlBlock(item, sorted, all, progress, results[1]);
        all = this._drawWxmlInline(item, sorted, all, progress, results[1]);

        Promise.all(all)
          .then(results => {
            resolve && resolve();
          })
          .catch(e => {
            reject && reject(e);
          });
      });
    } catch (e) {
      reject && reject({ errcode: 1008, errmsg: 'drawWxml error' });
    }
  }

  _drawWxmlBlock(item, sorted, all, progress, results) {
    let self = this;
    // 用来限定位置范围，取相对位置
    let limitLeft = results ? results.left : 0;
    let limitTop = results ? results.top : 0;
    Object.keys(sorted).forEach((top, topIndex) => {
      // 左 -> 右
      let list = sorted[top].sort((a, b) => {
        return a.left - b.left;
      });

      list = list.filter(sub => sub.dataset.type && sub.dataset.type.indexOf('inline') === -1);

      list.forEach((sub, index) => {
        all[index] = new Promise((resolve2, reject2) => {
          sub = self._transferWxmlStyle(sub, item, limitLeft, limitTop);
          sub.progress = progress;
          let type = sub.dataset.type;
          if (sub.dataset.delay) {
            setTimeout(() => {
              drawWxmlItem();
            }, sub.dataset.delay);
          } else {
            drawWxmlItem();
          }
          function drawWxmlItem() {
            if (type === 'text') {
              self._drawWxmlText(sub, resolve2, reject2);
            } else if (type === 'image') {
              self._drawWxmlImage(sub, resolve2, reject2);
            } else if (type === 'radius-image') {
              self._drawWxmlCircleImage(sub, resolve2, reject2);
            } else if (type === 'background-image') {
              self._drawWxmlBackgroundImage(sub, resolve2, reject2);
            }
          }
        });
      });
    });

    return all;
  }

  _drawWxmlInline(item, sorted, all, progress, results) {
    let self = this;
    let topOffset = 0;
    let leftOffset = 0;
    let lastTop = 0;
    let limitLeft = results ? results.left : 0;
    let limitTop = results ? results.top : 0;
    let p = new Promise((resolve2, reject2) => {
      let maxWidth = 0;
      let minLeft = Infinity;
      let maxRight = 0;

      // 找出同一top下的最小left和最大right，得到最大的宽度，用于换行
      Object.keys(sorted).forEach(top => {
        let inlineList = sorted[top].filter(sub => sub.dataset.type && sub.dataset.type.indexOf('inline') > -1);
        inlineList.forEach(sub => {
          if (sub.left < minLeft) {
            minLeft = sub.left;
          }
          if (sub.right > maxRight) {
            maxRight = sub.right;
          }
        });
      });
      maxWidth = Math.ceil(maxRight - minLeft || self.width);

      Object.keys(sorted).forEach((top, topIndex) => {
        // 左 -> 右
        let list = sorted[top].sort((a, b) => {
          return a.left - b.left;
        });

        // 换行的行内元素left放到后面，version2.0.6后无法获取高度，改用bottom值来判断是否换行了
        let position = -1;
        for (let i = 0, len = list.length; i < len; i++) {
          if (list[i] && list[i + 1]) {
            if (list[i].bottom > list[i + 1].bottom) {
              position = i;
              break;
            }
          }
        }

        if (position > -1) {
          list.push(list.splice(position, 1)[0]);
        }

        let inlineList = list.filter(sub => sub.dataset.type && sub.dataset.type.indexOf('inline') > -1);
        let originLeft = inlineList[0] ? inlineList[0].left : 0;
        // 换行后和top不相等时，认为是换行了，要清除左边距；当左偏移量大于最大宽度时，也要清除左边距; 当左偏移小于左边距时，也要清除
        if (
          Math.abs(topOffset + lastTop - top) > 2 ||
          leftOffset - originLeft - limitLeft >= maxWidth ||
          leftOffset <= originLeft - limitLeft - 2
        ) {
          leftOffset = 0;
        }

        lastTop = +top;
        topOffset = 0;

        inlineList.forEach((sub, index) => {
          sub = self._transferWxmlStyle(sub, item, limitLeft, limitTop);
          sub.progress = progress;
          let type = sub.dataset.type;
          if (type === 'inline-text') {
            let drawRes = self._drawWxmlInlineText(sub, leftOffset, maxWidth);
            leftOffset = drawRes.leftOffset;
            topOffset = drawRes.topOffset;
          } else if (type === 'inline-image') {
            let drawRes = self._drawWxmlImage(sub) || {};
            leftOffset = drawRes.leftOffset || 0;
            topOffset = drawRes.topOffset || 0;
          }
        });
      });
      resolve2();
    });

    all.push(p);
    return all;
  }

  _drawWxmlInlineText(sub, leftOffset = 0, maxWidth) {
    let text = sub.dataset.text || '';
    if (sub.dataset.maxlength && text.length > sub.dataset.maxlength) {
      text = text.substring(0, sub.dataset.maxlength) + '...';
    }

    let textData = {
      text,
      originX: sub.left,
      x: leftOffset ? leftOffset : sub.left,
      y: sub.top,
      progress: sub.progress,
      leftOffset: leftOffset,
      maxWidth: maxWidth, // 行内元素的最大宽度，取决于limit的宽度
    };

    if (sub.backgroundColor !== 'rgba(0, 0, 0, 0)') {
      sub.background = sub.backgroundColor;
    } else {
      sub.background = 'rgba(0, 0, 0, 0)';
    }

    if (sub.dataset.background) {
      sub.background = sub.dataset.background;
    }

    let res = this._drawText(textData, sub, null, null, 'inline-text', 'wxml');

    return res;
  }

  _drawWxmlText(sub, resolve, reject) {
    let text = sub.dataset.text || '';
    if (sub.dataset.maxlength && text.length > sub.dataset.maxlength) {
      text = text.substring(0, sub.dataset.maxlength) + '...';
    }

    let textData = {
      text,
      x: sub.left,
      y: sub.top,
      progress: sub.progress,
    };
    if (sub.backgroundColor !== 'rgba(0, 0, 0, 0)') {
      sub.background = sub.backgroundColor;
    } else {
      sub.background = 'rgba(0, 0, 0, 0)';
    }

    if (sub.dataset.background) {
      sub.background = sub.dataset.background;
    }

    this._drawText(textData, sub, resolve, reject, 'text', 'wxml');
  }

  _drawWxmlImage(sub, resolve, reject) {
    let imageData = {
      url: sub.dataset.url,
      x: sub.left,
      y: sub.top,
      progress: sub.progress,
    };

    let res = this._drawRect(imageData, sub, resolve, reject, 'image', 'inline-wxml');

    return res;
  }

  _drawWxmlCircleImage(sub, resolve, reject) {
    let imageData = {
      url: sub.dataset.url,
      x: sub.left,
      y: sub.top,
      progress: sub.progress,
    };
    sub.r = sub.width / 2;

    this._drawCircle(imageData, sub, resolve, reject, true, 'wxml');
  }

  _drawWxmlBackgroundImage(sub, resolve, reject) {
    let url = sub.dataset.url;
    let index = this._findPicIndex(url);
    url = index > -1 ? this.allPic[index].local : url;
    let size = sub.backgroundSize.replace(/px/g, '').split(' ');

    let imageData = {
      url: url,
      x: sub.left,
      y: sub.top,
      progress: sub.progress,
    };

    this._drawRect(imageData, sub, resolve, reject, 'image', 'wxml');
  }

  _getWxml(item, style) {
    const query = this.obj ? Taro.createSelectorQuery().in(this.obj) : Taro.createSelectorQuery();
    const self = this;

    const p1 = new Promise((resolve, reject) => {
      // 会触发两次，要限制
      let count = 0;
      query
        .selectAll(`${item.class}`)
        .fields(
          {
            dataset: true,
            size: true,
            rect: true,
            computedStyle: [
              'width',
              'height',
              'font',
              'fontSize',
              'fontFamily',
              'fontWeight',
              'fontStyle',
              'textAlign',
              'color',
              'lineHeight',
              'border',
              'borderColor',
              'borderStyle',
              'borderWidth',
              'verticalAlign',
              'boxShadow',
              'background',
              'backgroundColor',
              'backgroundImage',
              'backgroundPosition',
              'backgroundSize',
              'paddingLeft',
              'paddingTop',
              'paddingRight',
              'paddingBottom',
            ],
          },
          res => {
            if (count++ === 0) {
              let formated = self._formatImage(res);
              let list = formated.list;
              res = formated.res;

              self
                ._preloadImage(list)
                .then(result => {
                  resolve(res);
                })
                .catch(res => {
                  reject && reject({ errcode: 1009, errmsg: 'drawWxml preLoadImage error' });
                });
            }
          }
        )
        .exec();
    });

    const p2 = new Promise((resolve, reject) => {
      if (!item.limit) {
        resolve({ top: 0, width: self.width / self.zoom });
      }

      query
        .select(`${item.limit}`)
        .fields(
          {
            dataset: true,
            size: true,
            rect: true,
          },
          res => {
            resolve(res);
          }
        )
        .exec();
    });

    return Promise.all([p1, p2]);
  }

  _getLineHeight(style) {
    let zoom = this.zoom;
    if (style.dataset && style.dataset.type) {
      zoom = 1;
    }
    let lineHeight;
    if (!isNaN(style.lineHeight) && style.lineHeight > style.fontSize) {
      lineHeight = style.lineHeight;
    } else {
      style.lineHeight = (style.lineHeight || '') + '';
      lineHeight = +style.lineHeight.replace('px', '');
      lineHeight = lineHeight ? lineHeight : (style.fontSize || 14) * 1.2;
    }
    return lineHeight * zoom;
  }

  _formatImage(res = []) {
    const list = [];

    res.forEach((item, index) => {
      let dataset = item.dataset;
      let uid = getUid();
      let filename = `${Taro.env.USER_DATA_PATH}/${uid}.png`;
      if ((dataset.type === 'image' || dataset.type === 'radius-image') && dataset.url) {
        let sub = {
          url: dataset.base64 ? filename : dataset.url,
          isBase64: dataset.base64 ? dataset.url : false,
        };

        res[index].dataset = Object.assign(res[index].dataset, sub);
        list.push(sub);
      } else if (dataset.type === 'background-image' && item.backgroundImage.indexOf('url') > -1) {
        let url = item.backgroundImage.replace(/url\((\"|\')?/, '').replace(/(\"|\')?\)$/, '');
        let sub = {
          url: dataset.base64 ? filename : url,
          isBase64: dataset.base64 ? url : false,
        };
        res[index].dataset = Object.assign(res[index].dataset, sub);
        list.push(sub);
      }
    });

    return { list, res };
  }

  _updateProgress(distance) {
    this.progressPercent += distance;
    this.progress(this.progressPercent);
  }

  _sortListByTop(list = []) {
    let sorted = {};

    // 粗略地认为2px相差的元素在同一行
    list.forEach((item, index) => {
      let top = item.top;
      if (!sorted[top]) {
        if (sorted[top - 2]) {
          top = top - 2;
        } else if (sorted[top - 1]) {
          top = top - 1;
        } else if (sorted[top + 1]) {
          top = top + 1;
        } else if (sorted[top + 2]) {
          top = top + 2;
        } else {
          sorted[top] = [];
        }
      }
      sorted[top].push(item);
    });

    return sorted;
  }

  _parseNumber(number) {
    return isNaN(number) ? +(number || '').replace('px', '') : number;
  }

  _transferWxmlStyle(sub, item, limitLeft, limitTop) {
    let leftFix = +sub.dataset.left || 0;
    let topFix = +sub.dataset.top || 0;

    sub.width = this._parseNumber(sub.width);
    sub.height = this._parseNumber(sub.height);
    sub.left = this._parseNumber(sub.left) - limitLeft + (leftFix + (item.x || 0)) * this.zoom;
    sub.top = this._parseNumber(sub.top) - limitTop + (topFix + (item.y || 0)) * this.zoom;

    let padding = sub.dataset.padding || '0 0 0 0';
    if (typeof padding === 'string') {
      padding = transferPadding(padding);
    }
    let paddingTop = Number(sub.paddingTop.replace('px', '')) + Number(padding[0]);
    let paddingRight = Number(sub.paddingRight.replace('px', '')) + Number(padding[1]);
    let paddingBottom = Number(sub.paddingBottom.replace('px', '')) + Number(padding[2]);
    let paddingLeft = Number(sub.paddingLeft.replace('px', '')) + Number(padding[3]);
    sub.padding = [paddingTop, paddingRight, paddingBottom, paddingLeft];

    return sub;
  }

  /**
   * 支持负值绘制，从右边计算
   * @param {*} item
   * @param {*} style
   */
  _resetPositionX(item, style) {
    let zoom = this.zoom;
    let x = 0;

    if (style.dataset && style.dataset.type) {
      zoom = 1;
    }

    // 通过wxml获取的不需要重置坐标
    if (item.x < 0 && item.type) {
      x = this.width + item.x * zoom - style.width * zoom;
    } else {
      x = item.x * zoom;
    }

    if (parseInt(style.borderWidth)) {
      x += parseInt(style.borderWidth);
    }

    return x + this.translateX;
  }

  /**
   * 支持负值绘制，从底部计算
   * @param {*} item
   * @param {*} style
   */
  _resetPositionY(item, style, textHeight) {
    let zoom = this.zoom;
    let y = 0;

    if (style.dataset && style.dataset.type) {
      zoom = 1;
    }

    if (item.y < 0) {
      y = this.height + item.y * zoom - (textHeight ? textHeight : style.height * zoom);
    } else {
      y = item.y * zoom;
    }

    if (parseInt(style.borderWidth)) {
      y += parseInt(style.borderWidth);
    }

    return y + this.translateY;
  }

  /**
   * 文字的padding、text-align
   * @param {*} item
   * @param {*} style
   * @param {*} textWidth
   */
  _resetTextPositionX(item, style, textWidth, width) {
    let textAlign = style.textAlign || 'left';
    let x = item.x;
    if (textAlign === 'center') {
      x = (width - textWidth) / 2 + item.x;
    } else if (textAlign === 'right') {
      x = width - textWidth + item.x;
    }

    let left = style.padding ? style.padding[3] || 0 : 0;

    return x + left + this.translateX;
  }

  /**
   * 文字的padding、text-align
   * @param {*} item
   * @param {*} style
   * @param {*} textWidth
   */
  _resetTextPositionY(item, style, lineNum = 0) {
    let zoom = this.zoom;
    if (style.dataset && style.dataset.type) {
      zoom = 1;
    }

    let lineHeight = this._getLineHeight(style);
    let fontSize = Math.ceil((style.fontSize || 14) * zoom);

    let blockLineHeightFix =
      ((style.dataset && style.dataset.type) || '').indexOf('inline') > -1 ? 0 : (lineHeight - fontSize) / 2;

    let top = style.padding ? style.padding[0] || 0 : 0;

    // y + lineheight偏移 + 行数 + paddingTop + 整体画布位移
    return item.y + blockLineHeightFix + lineNum * lineHeight + top + this.translateY;
  }

  /**
   * 当文本超过宽度时，计算每一行应该绘制的文本
   * @param {*} text
   * @param {*} width
   * @param {*} singleLength
   * @param {*} currentIndex
   * @param {*} widthOffset
   */
  _getTextSingleLine(text, width, singleLength, currentIndex = 0, widthOffset = 0) {
    let offset = 0;
    let endIndex = currentIndex + singleLength + offset;
    let single = text.substring(currentIndex, endIndex);
    let singleWidth = this.measureWidth(single);

    while (Math.round(widthOffset + singleWidth) > width) {
      offset--;
      endIndex = currentIndex + singleLength + offset;
      single = text.substring(currentIndex, endIndex);
      singleWidth = this.measureWidth(single);
    }

    return {
      endIndex,
      single,
      singleWidth,
    };
  }

  _drawBorder(border, style, callback) {
    let zoom = this.zoom;
    if (style.dataset && style.dataset.type) {
      zoom = 1;
    }
    border = transferBorder(border);

    if (border && border.width) {
      // 空白阴影，清空掉边框的阴影
      this._drawBoxShadow();
      if (border) {
        this.ctx.setLineWidth(border.width * zoom);

        if (border.style === 'dashed') {
          let dash = style.dash || [5, 5, 0];
          let offset = dash[2] || 0;
          let array = [dash[0] || 5, dash[1] || 5];
          this.ctx.setLineDash(array, offset);
        }
        this.ctx.setStrokeStyle(border.color);
      }
      callback && callback(border);
    }
  }

  _drawBoxShadow(boxShadow, callback) {
    boxShadow = transferBoxShadow(boxShadow);
    if (boxShadow) {
      this.ctx.setShadow(boxShadow.offsetX, boxShadow.offsetY, boxShadow.blur, boxShadow.color);
    } else {
      this.ctx.setShadow(0, 0, 0, '#ffffff');
    }

    callback && callback(boxShadow || {});
  }

  _setFill(fill, callback) {
    if (fill) {
      if (typeof fill === 'string') {
        this.ctx.setFillStyle(fill);
      } else {
        let line = fill.line;
        let color = fill.color;
        let grd = this.ctx.createLinearGradient(line[0], line[1], line[2], line[3]);
        grd.addColorStop(0, color[0]);
        grd.addColorStop(1, color[1]);
        this.ctx.setFillStyle(grd);
      }
      callback && callback();
    }
  }

  _setStroke(stroke, callback) {
    if (stroke) {
      if (typeof stroke === 'string') {
        this.ctx.setStrokeStyle(stroke);
      } else {
        let line = stroke.line;
        let color = stroke.color;
        let grd = this.ctx.createLinearGradient(line[0], line[1], line[2], line[3]);
        grd.addColorStop(0, color[0]);
        grd.addColorStop(1, color[1]);
        this.ctx.setStrokeStyle(grd);
      }

      callback && callback();
    }
  }
}