refactor: interfaces to protocols

src/converters/xml-mathml-to-latex/XmlMathMLToLaTeX.ts

@@ -1,4 +1,4 @@
-import { MathML } from '../../interfaces/MathML';
+import { MathML } from '../../protocols/MathML';
 import MathmlToLatex from './xml-to-mathml/mathml-to-latex';
 import XmlToMathml from './xml-to-mathml';
 

src/converters/xml-mathml-to-latex/xml-to-mathml/ElementsToMathMLAdapter.ts

@@ -1,4 +1,4 @@
-import { MathML } from '../../../interfaces/MathML';
+import { MathML } from '../../../protocols/MathML';
 
 export class ElementsToMathMLAdapter {
   convert(els: Element[]): MathML[] {

src/converters/xml-mathml-to-latex/xml-to-mathml/XmlToMathMLAdapter.ts

@@ -2,7 +2,7 @@ import xmldom = require('xmldom');
 
 import { DOMParser } from 'xmldom';
 import { ErrorHandler } from './ErrorHandler';
-import { MathML } from '../../../interfaces/MathML';
+import { MathML } from '../../../protocols/MathML';
 import { ElementsToMathMLAdapter } from './ElementsToMathMLAdapter';
 
 export class XmlToMathMLAdapter {

src/converters/xml-mathml-to-latex/xml-to-mathml/mathml-to-latex/MathMLToLaTeX.ts

@@ -1,4 +1,4 @@
-import { MathML } from '../../../../interfaces/MathML';
+import { MathML } from '../../../../protocols/MathML';
 import Dispatcher from './mathml-to-latex';
 import { MathMLTag } from './mathml-to-latex/mathml-tags';
 

src/converters/xml-to-mathml/ElementsToMathMLAdapter.ts

@@ -0,0 +1,33 @@
+import { MathML } from '../../protocols/MathML';
+
+export class ElementsToMathMLAdapter {
+  convert(els: Element[]): MathML[] {
+    return els.filter((el: Element) => el.tagName !== undefined).map((el: Element) => this._convertElement(el));
+  }
+
+  private _convertElement(el: Element): MathML {
+    return {
+      name: el.tagName,
+      attributes: el.attributes ? this._convertElementAttributes(el.attributes) : {},
+      value: this._hasElementChild(el) ? '' : el.textContent || '',
+      children: this._hasElementChild(el) ? this.convert(Array.from(el.childNodes) as Element[]) : ([] as MathML[]),
+    };
+  }
+
+  private _convertElementAttributes(attributes: NamedNodeMap): Record<string, string> {
+    return Array.from(attributes).reduce(
+      (acc, attr: Attr) =>
+        Object.assign({ [attr.nodeName]: attr.nodeValue === attr.nodeName ? '' : attr.nodeValue }, acc),
+      {},
+    );
+  }
+
+  private _hasElementChild(el: Element): boolean {
+    const childNodes = el.childNodes;
+    return !!childNodes && childNodes.length !== 0 && this._isThereAnyNoTextNode(childNodes);
+  }
+
+  private _isThereAnyNoTextNode(children: NodeListOf<ChildNode>): boolean {
+    return Array.from(children).some((child) => child.nodeName !== '#text');
+  }
+}

src/converters/xml-to-mathml/XmlToMathMLAdapter.ts

@@ -0,0 +1,42 @@
+import xmldom = require('xmldom');
+
+import { DOMParser } from 'xmldom';
+import { ErrorHandler } from './ErrorHandler';
+import { MathML } from '../../protocols/MathML';
+import { ElementsToMathMLAdapter } from './ElementsToMathMLAdapter';
+
+export class XmlToMathMLAdapter {
+  private _xmlDOM: DOMParser;
+  private _errorHandler: ErrorHandler;
+  private _elementsConvertor: ElementsToMathMLAdapter;
+
+  constructor(private _xml: string) {
+    this._xml = this._removeLineBreaks(_xml);
+
+    this._elementsConvertor = new ElementsToMathMLAdapter();
+    this._errorHandler = new ErrorHandler();
+
+    this._xmlDOM = new xmldom.DOMParser({
+      locator: this._errorHandler.errorLocator,
+      errorHandler: this._fixError.bind(this),
+    });
+  }
+
+  convert(): MathML[] {
+    return this._elementsConvertor.convert(this._mathMLElements);
+  }
+
+  private _fixError(errorMessage: string): void {
+    this._xml = this._errorHandler.fixError(this._xml, errorMessage);
+  }
+
+  private _removeLineBreaks(xml: string): string {
+    const LINE_BREAK = /\n|\r\n|\r/g;
+    return xml.replace(LINE_BREAK, '');
+  }
+
+  private get _mathMLElements(): Element[] {
+    const elements = this._xmlDOM.parseFromString(this._xml).getElementsByTagName('math');
+    return Array.from(elements) as Element[];
+  }
+}