lindell / JsBarcode

import merge from "../help/merge.js";

import {calculateEncodingAttributes, getTotalWidthOfEncodings, getMaximumHeightOfEncodings} from "./shared.js";

var svgns = "http://www.w3.org/2000/svg";

class SVGRenderer{

	constructor(svg, encodings, options){

		this.svg = svg;

		this.encodings = encodings;

		this.options = options;

		this.document = options.xmlDocument || document;

	}

	render(){

		var currentX = this.options.marginLeft;

		this.prepareSVG();

		for(let i = 0; i < this.encodings.length; i++){

			var encoding = this.encodings[i];

			var encodingOptions = merge(this.options, encoding.options);

			var group = this.createGroup(currentX, encodingOptions.marginTop, this.svg);

			this.setGroupOptions(group, encodingOptions);

			this.drawSvgBarcode(group, encodingOptions, encoding);

			this.drawSVGText(group, encodingOptions, encoding);

			currentX += encoding.width;

		}

	}

	prepareSVG(){

		// Clear the SVG

		while (this.svg.firstChild) {

			this.svg.removeChild(this.svg.firstChild);

		}

		calculateEncodingAttributes(this.encodings, this.options);

		var totalWidth = getTotalWidthOfEncodings(this.encodings);

		var maxHeight = getMaximumHeightOfEncodings(this.encodings);

		var width = totalWidth + this.options.marginLeft + this.options.marginRight;

		this.setSvgAttributes(width, maxHeight);

		if(this.options.background){

			this.drawRect(0, 0, width, maxHeight, this.svg).setAttribute(

				"style", "fill:" + this.options.background + ";"

			);

		}

	}

	drawSvgBarcode(parent, options, encoding){

		var binary = encoding.data;

		// Creates the barcode out of the encoded binary

		var yFrom;

		if(options.textPosition == "top"){

			yFrom = options.fontSize + options.textMargin;

		}

		else{

			yFrom = 0;

		}

		var barWidth = 0;

		var x = 0;

		for(var b = 0; b < binary.length; b++){

			x = b * options.width + encoding.barcodePadding;

			if(binary[b] === "1"){

				barWidth++;

			}

			else if(barWidth > 0){

				this.drawRect(x - options.width * barWidth, yFrom, options.width * barWidth, options.height, parent);

				barWidth = 0;

			}

		}

		// Last draw is needed since the barcode ends with 1

		if(barWidth > 0){

			this.drawRect(x - options.width * (barWidth - 1), yFrom, options.width * barWidth, options.height, parent);

		}

	}

	drawSVGText(parent, options, encoding){

		var textElem = this.document.createElementNS(svgns, 'text');

		// Draw the text if displayValue is set

		if(options.displayValue){

			var x, y;

			textElem.setAttribute("style",

				"font:" + options.fontOptions + " " + options.fontSize + "px " + options.font

			);

			if(options.textPosition == "top"){

				y = options.fontSize - options.textMargin;

			}

			else{

				y = options.height + options.textMargin + options.fontSize;

			}

			// Draw the text in the correct X depending on the textAlign option

			if(options.textAlign == "left" || encoding.barcodePadding > 0){

				x = 0;

				textElem.setAttribute("text-anchor", "start");

			}

			else if(options.textAlign == "right"){

				x = encoding.width - 1;

				textElem.setAttribute("text-anchor", "end");

			}

			// In all other cases, center the text

			else{

				x = encoding.width / 2;

				textElem.setAttribute("text-anchor", "middle");

			}

			textElem.setAttribute("x", x);

			textElem.setAttribute("y", y);

			textElem.appendChild(this.document.createTextNode(encoding.text));

			parent.appendChild(textElem);

		}

	}

	setSvgAttributes(width, height){

		var svg = this.svg;

		svg.setAttribute("width", width + "px");

		svg.setAttribute("height", height + "px");

		svg.setAttribute("x", "0px");

		svg.setAttribute("y", "0px");

		svg.setAttribute("viewBox", "0 0 " + width + " " + height);

		svg.setAttribute("xmlns", svgns);

		svg.setAttribute("version", "1.1");

		svg.setAttribute("style", "transform: translate(0,0)");

	}

	createGroup(x, y, parent){

		var group = this.document.createElementNS(svgns, 'g');

		group.setAttribute("transform", "translate(" + x + ", " + y + ")");

		parent.appendChild(group);

		return group;

	}

	setGroupOptions(group, options){

		group.setAttribute("style",

			"fill:" + options.lineColor + ";"

		);

	}

	drawRect(x, y, width, height, parent){

		var rect = this.document.createElementNS(svgns, 'rect');

		rect.setAttribute("x", x);

		rect.setAttribute("y", y);

		rect.setAttribute("width", width);

		rect.setAttribute("height", height);

		parent.appendChild(rect);

		return rect;

	}

}

export default SVGRenderer;