epub.js/lib/epubjs/layout.js

EPUBJS.Layout = EPUBJS.Layout || {};

EPUBJS.Layout.Reflowable = function(view){
  // this.documentElement = null;
  this.view = view;
  this.spreadWidth = null;
};

EPUBJS.Layout.Reflowable.prototype.format = function(documentElement, _width, _height, _gap){
  // Get the prefixed CSS commands
  var columnAxis = EPUBJS.core.prefixed('columnAxis');
  var columnGap = EPUBJS.core.prefixed('columnGap');
  var columnWidth = EPUBJS.core.prefixed('columnWidth');
  var columnFill = EPUBJS.core.prefixed('columnFill');

  //-- Check the width and create even width columns
  var width = Math.floor(_width);
  // var width = (fullWidth % 2 === 0) ? fullWidth : fullWidth - 0; // Not needed for single
  var section = Math.floor(width / 8);
  var gap = (_gap >= 0) ? _gap : ((section % 2 === 0) ? section : section - 1);
  this.documentElement = documentElement;
  //-- Single Page
  this.spreadWidth = (width + gap);


  documentElement.style.overflow = "hidden";

  // Must be set to the new calculated width or the columns will be off
  documentElement.style.width = width + "px";

  //-- Adjust height
  documentElement.style.height = _height + "px";

  //-- Add columns
  documentElement.style[columnAxis] = "horizontal";
  documentElement.style[columnFill] = "auto";
  documentElement.style[columnWidth] = width+"px";
  documentElement.style[columnGap] = gap+"px";
  this.colWidth = width;
  this.gap = gap;

  return {
    pageWidth : this.spreadWidth,
    pageHeight : _height
  };
};

EPUBJS.Layout.Reflowable.prototype.calculatePages = function() {
  var totalWidth, displayedPages;
  this.documentElement.style.width = "auto"; //-- reset width for calculations
  totalWidth = this.documentElement.scrollWidth;
  displayedPages = Math.ceil(totalWidth / this.spreadWidth);

  return {
    displayedPages : displayedPages,
    pageCount : displayedPages
  };
};

EPUBJS.Layout.ReflowableSpreads = function(view){
  this.view = view;
  this.documentElement = view.document.documentElement;
  this.spreadWidth = null;
};

EPUBJS.Layout.ReflowableSpreads.prototype.format = function(_width, _height, _gap){
  var columnAxis = EPUBJS.core.prefixed('columnAxis');
  var columnGap = EPUBJS.core.prefixed('columnGap');
  var columnWidth = EPUBJS.core.prefixed('columnWidth');
  var columnFill = EPUBJS.core.prefixed('columnFill');

  var divisor = 2,
      cutoff = 800;

  //-- Check the width and create even width columns
  var fullWidth = Math.floor(_width);
  var width = (fullWidth % 2 === 0) ? fullWidth : fullWidth - 1;

  var section = Math.floor(width / 8);
  var gap = (_gap >= 0) ? _gap : ((section % 2 === 0) ? section : section - 1);

  //-- Double Page
  var colWidth = Math.floor((width - gap) / divisor);

  this.spreadWidth = (colWidth + gap) * divisor;


  this.view.document.documentElement.style.overflow = "hidden";

  // Must be set to the new calculated width or the columns will be off
  this.view.document.body.style.width = width + "px";

  //-- Adjust height
  this.view.document.body.style.height = _height + "px";

  //-- Add columns
  this.view.document.body.style[columnAxis] = "horizontal";
  this.view.document.body.style[columnFill] = "auto";
  this.view.document.body.style[columnGap] = gap+"px";
  this.view.document.body.style[columnWidth] = colWidth+"px";

  this.colWidth = colWidth;
  this.gap = gap;

  // this.view.document.body.style.paddingRight = gap + "px";
  // view.iframe.style.width = this.spreadWidth+"px";
  // this.view.element.style.paddingRight = gap+"px";
  // view.iframe.style.paddingLeft = gap+"px";

  return {
    pageWidth : this.spreadWidth,
    pageHeight : _height
  };
};

EPUBJS.Layout.ReflowableSpreads.prototype.calculatePages = function(view) {
  var totalWidth = this.documentElement.scrollWidth;
  var displayedPages = Math.ceil(totalWidth / this.spreadWidth);

  //-- Add a page to the width of the document to account an for odd number of pages
  // this.documentElement.style.width = totalWidth + this.spreadWidth + "px";
  return {
    displayedPages : displayedPages,
    pageCount : displayedPages * 2
  };
};

EPUBJS.Layout.Fixed = function(){
  this.documentElement = null;
};

EPUBJS.Layout.Fixed = function(documentElement, _width, _height, _gap){
  var columnWidth = EPUBJS.core.prefixed('columnWidth');
  var viewport = documentElement.querySelector("[name=viewport");
  var content;
  var contents;
  var width, height;

  this.documentElement = documentElement;
  /**
  * check for the viewport size
  * <meta name="viewport" content="width=1024,height=697" />
  */
  if(viewport && viewport.hasAttribute("content")) {
    content = viewport.getAttribute("content");
    contents = content.split(',');
    if(contents[0]){
      width = contents[0].replace("width=", '');
    }
    if(contents[1]){
      height = contents[1].replace("height=", '');
    }
  }

  //-- Adjust width and height
  documentElement.style.width =  width + "px" || "auto";
  documentElement.style.height =  height + "px" || "auto";

  //-- Remove columns
  documentElement.style[columnWidth] = "auto";

  //-- Scroll
  documentElement.style.overflow = "auto";

  this.colWidth = width;
  this.gap = 0;

  return {
    pageWidth : width,
    pageHeight : height
  };

};

EPUBJS.Layout.Fixed.prototype.calculatePages = function(){
  return {
    displayedPages : 1,
    pageCount : 1
  };
};