From 7013be6825832cca31d07ecddd65d06f8cca922e Mon Sep 17 00:00:00 2001
From: Sauli Anto <sauli.anto@gmail.com>
Date: Sun, 29 Sep 2019 04:14:02 +0300
Subject: [PATCH] Add paste from word base

---
 package-lock.json          |  10 ++
 package.json               |   1 +
 src/math.js                |   3 +-
 src/mathpastefromoffice.js | 263 +++++++++++++++++++++++++++++++++++++
 4 files changed, 276 insertions(+), 1 deletion(-)
 create mode 100644 src/mathpastefromoffice.js

diff --git a/package-lock.json b/package-lock.json
index 03734e959..84f74a7db 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -90,6 +90,16 @@
         "@ckeditor/ckeditor5-undo": "^11.0.5"
       }
     },
+    "@ckeditor/ckeditor5-paste-from-office": {
+      "version": "11.1.0",
+      "resolved": "https://registry.npmjs.org/@ckeditor/ckeditor5-paste-from-office/-/ckeditor5-paste-from-office-11.1.0.tgz",
+      "integrity": "sha512-LcXmJSlr0fzi+hccdyTnHuKh/K9nWV5OiuWqcOpX3IucczSYzGgykG4MUZVlBLv1mkP0AsjJ1oSPGXCkVkgJkg==",
+      "requires": {
+        "@ckeditor/ckeditor5-clipboard": "^12.0.2",
+        "@ckeditor/ckeditor5-core": "^12.3.0",
+        "@ckeditor/ckeditor5-engine": "^14.0.0"
+      }
+    },
     "@ckeditor/ckeditor5-typing": {
       "version": "12.2.0",
       "resolved": "https://registry.npmjs.org/@ckeditor/ckeditor5-typing/-/ckeditor5-typing-12.2.0.tgz",
diff --git a/package.json b/package.json
index d2768c468..81cf29503 100644
--- a/package.json
+++ b/package.json
@@ -13,6 +13,7 @@
     "@ckeditor/ckeditor5-clipboard": "^12.0.2",
     "@ckeditor/ckeditor5-core": "^12.3.0",
     "@ckeditor/ckeditor5-engine": "^14.0.0",
+    "@ckeditor/ckeditor5-paste-from-office": "^11.1.0",
     "@ckeditor/ckeditor5-ui": "^14.0.0",
     "@ckeditor/ckeditor5-undo": "^11.0.5",
     "@ckeditor/ckeditor5-utils": "^14.0.0",
diff --git a/src/math.js b/src/math.js
index 73f753082..a828653c5 100644
--- a/src/math.js
+++ b/src/math.js
@@ -4,10 +4,11 @@ import Widget from '@ckeditor/ckeditor5-widget/src/widget';
 import MathUI from './mathui';
 import MathEditing from './mathediting';
 import AutoMath from './automath';
+import MathPasteFromOffice from './mathpastefromoffice';
 
 export default class Math extends Plugin {
 	static get requires() {
-		return [ MathEditing, MathUI, Widget, AutoMath ];
+		return [ MathEditing, MathUI, Widget, AutoMath, MathPasteFromOffice ];
 	}
 
 	static get pluginName() {
diff --git a/src/mathpastefromoffice.js b/src/mathpastefromoffice.js
new file mode 100644
index 000000000..f7bc792fd
--- /dev/null
+++ b/src/mathpastefromoffice.js
@@ -0,0 +1,263 @@
+import Plugin from '@ckeditor/ckeditor5-core/src/plugin';
+import Clipboard from '@ckeditor/ckeditor5-clipboard/src/clipboard';
+import UpcastWriter from '@ckeditor/ckeditor5-engine/src/view/upcastwriter';
+import Matcher from '@ckeditor/ckeditor5-engine/src/view/matcher';
+// import Element from '@ckeditor/ckeditor5-engine/src/view/element';
+import { normalizeSpacing, normalizeSpacerunSpans } from '@ckeditor/ckeditor5-paste-from-office/src/filters/space';
+
+const BULLET_REGEXP = /(<span style=['"]mso-list:((.||\r?\n)*?)Ignore['"]>((.|\r?\n)*?)<\/span>)/g;
+
+export default class MathPasteFromOffice extends Plugin {
+	static get pluginName() {
+		return 'MathPasteFromOffice';
+	}
+
+	static get requires() {
+		return [ Clipboard ];
+	}
+
+	init() {
+		const editor = this.editor;
+
+		editor.plugins.get( 'Clipboard' ).on(
+			'inputTransformation',
+			( evt, data ) => {
+				console.log( 'isTransformedWithPasteFromOffice', data.isTransformedWithPasteFromOffice ); // eslint-disable-line
+				console.log( data.content ); // eslint-disable-line
+
+				if ( data.isTransformedWithMathPasteFromOffice ) {
+					return;
+				}
+
+				if ( !data.isTransformedWithPasteFromOffice ) {
+					console.warn( 'Paste from office must be set before this' );// eslint-disable-line
+					return;
+				}
+
+				const domParser = new DOMParser(); // eslint-disable-line
+
+				/*
+				console.log(htmlString); // eslint-disable-line
+				const { body } = parseHtml( htmlString );
+				console.log(body); // eslint-disable-line
+				*/
+
+				const plainString = data.dataTransfer.getData( 'text/plain' );
+				const lines = plainString.split( /\r?\n/ ); // split by new lines
+				if ( lines.length > 1 ) {
+					lines.pop(); // Remove last new line
+				}
+				// console.log(plainString); // eslint-disable-line
+
+				const htmlMimeType = 'text/html';
+				let htmlString = data.dataTransfer.getData( htmlMimeType );
+				// console.log(htmlString); // eslint-disable-line
+
+				htmlString = htmlString.replace( /<!--\[if gte vml 1]>/g, '' );
+				htmlString = htmlString.replace( BULLET_REGEXP, '' );
+
+				const normalizedHtml = normalizeSpacing( cleanContentAfterBody( htmlString ) );
+				const htmlDocument = domParser.parseFromString( normalizedHtml, htmlMimeType );
+				normalizeSpacerunSpans( htmlDocument );
+
+				// const htmlDocument = domParser.parseFromString( htmlString, htmlMimeType );
+				// console.log(htmlDocument); // eslint-disable-line
+
+				const parts = htmlDocument.body.children;
+
+				// console.log(parts); // eslint-disable-line
+
+				const partsByLines = [];
+
+				for ( let i = 0; i < parts.length; i++ ) {
+					const part = parts[ i ];
+					if ( part.tagName.toLowerCase() === 'table' ) {
+						// console.log(part); // eslint-disable-line
+						const table = part;
+						const rows = table.getElementsByTagName( 'tr' );
+						for ( let j = 0; j < rows.length; j++ ) {
+							const row = rows[ j ];
+							partsByLines.push( row );
+						}
+						// console.log(rows); // eslint-disable-line
+					} else {
+						partsByLines.push( part );
+					}
+				}
+
+				// console.log(lines); // eslint-disable-line
+				// console.log(parts); // eslint-disable-line
+				// console.log(lines.length, partsByLines.length); // eslint-disable-line
+
+				if ( lines.length === partsByLines.length ) {
+					for ( let i = 0; i < partsByLines.length; i++ ) {
+						const part = partsByLines[ i ];
+						const line = lines[ i ];
+
+						const nodes = part.childNodes;
+						// console.log( nodes ); // eslint-disable-line
+
+						let lineFromNode = '';
+						let equationCounter = 0;
+						for ( let j = 0; j < nodes.length; j++ ) {
+							const node = nodes[ j ];
+							// If node is comment
+							const commentType = Node.COMMENT_NODE; // eslint-disable-line
+							if ( node.nodeType === commentType ) {
+								const commentNode = node;
+								// console.log( comment ); // eslint-disable-line
+								const comment = commentNode.textContent;
+								// console.log(comment); // eslint-disable-line
+								if ( comment.match( /\[if gte msEquation 12]>/g ) ) {
+									equationCounter++;
+								}
+							}
+							if ( node.nodeType === Node.ELEMENT_NODE || node.nodeType === Node.TEXT_NODE ) { // eslint-disable-line
+								// console.log( node.nodeType, node.textContent ); // eslint-disable-line
+								lineFromNode += node.textContent;
+							}
+						}
+
+						// Skip if don't have any equation
+						if ( equationCounter === 0 ) {
+							continue;
+						}
+
+						const equations = collectEquations( line, lineFromNode, equationCounter );
+						// console.log( part, equations ); // eslint-disable-line
+
+						const images = part.getElementsByTagName( 'img' );
+						// console.log( images ); // eslint-disable-line
+						for ( let j = 0; j < images.length; j++ ) {
+							const img = images[ j ];
+							// console.log( img.src ); // eslint-disable-line
+
+							const mathtex = document.createElement( 'span' ); // eslint-disable-line
+							mathtex.classList.add( 'math-tex' );
+							mathtex.innerHTML = '\\[' + equations[ j ] + '\\]';
+
+							const parent = img.parentNode;
+							parent.replaceChild( mathtex, img );
+
+							// console.log( parent ); // eslint-disable-line
+						}
+					}
+
+					const writer = new UpcastWriter();
+					const documentFragment = data.content;
+					const itemLikeElements = findAllItemLikeElements( documentFragment, writer );
+					console.log( itemLikeElements ); // eslint-disable-line
+
+					if ( !itemLikeElements.length ) {
+						return;
+					}
+
+					itemLikeElements.forEach( ( itemLikeElement, i ) => {
+						console.log( i, itemLikeElement, itemLikeElement.element ); // eslint-disable-line
+						// const item = new Element( 'span' );
+					} );
+				} else {
+					console.warn( 'Lines length is wrong',  lines.length + ' !== ' + partsByLines.length ); // eslint-disable-line
+				}
+
+				data.isTransformedWithMathPasteFromOffice = true;
+			},
+			{ priority: 'high' }
+		);
+	}
+}
+
+function collectEquations( line, lineFromNode, equationCounter ) {
+	const equations = [];
+	let equation = '';
+	let charCounter = 0;
+	let newEquation = true;
+
+	// Replace all spaces to non breaking spaces. (Cannot be in equation)
+	let lineFiltered = line;
+	lineFiltered = lineFiltered.replace( /&nbsp;/g, ' ' );
+	lineFiltered = lineFiltered.trim();
+
+	// Remove '\ ' chars
+	lineFiltered = lineFiltered.replace( /\\ /g, '' ); // Remove all extra spaces.
+
+	// Try remove all spaces in equation
+	lineFiltered = lineFiltered.replace( /{(?=.*?)(?=\\+).*?}/g, match => {
+		return match.replace( /\s+/g, '' );
+	} ); // Remove all extra spaces.
+	lineFiltered = lineFiltered.replace( /\s/g, '\u00A0' ); // Replcae all spaces to non breaking spaces
+
+	let lineFromNodeFiltered = lineFromNode;
+	lineFromNodeFiltered = lineFromNodeFiltered.replace( /\r?\n|\r/g, ' ' ); // Line break is same as space
+	lineFromNodeFiltered = lineFromNodeFiltered.replace( /&nbsp;/g, ' ' );
+	lineFromNodeFiltered = lineFromNodeFiltered.trim();
+	lineFromNodeFiltered = lineFromNodeFiltered.replace( /\s/g, '\u00A0' ); // Replcae all spaces to non breaking spaces
+
+	// eslint-disable-next-line
+	// console.log( '%c' + lineFiltered + ' %c' + lineFromNodeFiltered + ' %c', 'color:green', 'color:red','color:white' );
+
+	// Let check line char by char
+	for ( let j = 0; j < lineFiltered.length; j++ ) {
+		const charFromLine = lineFiltered.charAt( j );
+		// console.log( charFromLine, lineFiltered.charCodeAt( j ) ); // eslint-disable-line
+		const charFromNode = lineFromNodeFiltered.charAt( j - charCounter );
+		// Jump to next iteration if same char
+		// console.log( charFromLine, charFromNode ); // eslint-disable-line
+		if ( charFromLine === charFromNode ) {
+			if ( !newEquation ) {
+				equations.push( equation.trim() );
+				equation = '';
+				newEquation = true;
+			}
+			continue;
+		} else {
+			equation += charFromLine;
+			charCounter++;
+			if ( newEquation ) {
+				newEquation = false;
+			}
+		}
+	}
+	// Add last one
+	if ( !newEquation ) {
+		equations.push( equation.trim() );
+		equation = '';
+		newEquation = true;
+	}
+
+	if ( equations.length !== equationCounter ) {
+		console.warn( 'Couldn\'t parse all equations' ); // eslint-disable-line
+	}
+
+	return equations;
+}
+
+function cleanContentAfterBody( htmlString ) {
+	const regexp = /<\/body>(.*?)(<\/html>|$)/;
+	const match = htmlString.match( regexp );
+
+	if ( match && match[ 1 ] ) {
+		htmlString = htmlString.slice( 0, match.index ) + htmlString.slice( match.index ).replace( match[ 1 ], '' );
+	}
+
+	return htmlString;
+}
+
+function findAllItemLikeElements( documentFragment, writer ) {
+	const range = writer.createRangeIn( documentFragment );
+
+	// Matcher for finding list-like elements.
+	const itemLikeElementsMatcher = new Matcher( {
+		name: /^img$/
+	} );
+
+	const itemLikeElements = [];
+
+	for ( const value of range ) {
+		if ( value.type === 'elementStart' && itemLikeElementsMatcher.match( value.item ) ) {
+			itemLikeElements.push( value.item );
+		}
+	}
+
+	return itemLikeElements;
+}