Spellcheck - first try to fix #2176

browser/components/CodeEditor.js

@@ -11,9 +11,12 @@ import eventEmitter from 'browser/main/lib/eventEmitter'
 import iconv from 'iconv-lite'
 import crypto from 'crypto'
 import consts from 'browser/lib/consts'
+import styles from '../components/CodeEditor.styl'
 import fs from 'fs'
-const { ipcRenderer } = require('electron')
+const { ipcRenderer, remote } = require('electron')
 import normalizeEditorFontFamily from 'browser/lib/normalizeEditorFontFamily'
+const spellcheck = require('browser/lib/spellcheck')
+const buildEditorContextMenu = require('browser/lib/contextMenuBuilder')
 
 CodeMirror.modeURL = '../node_modules/codemirror/mode/%N/%N.js'
 
@@ -29,7 +32,7 @@ export default class CodeEditor extends React.Component {
       leading: false,
       trailing: true
     })
-    this.changeHandler = e => this.handleChange(e)
+    this.changeHandler = (editor, changeObject) => this.handleChange(editor, changeObject)
     this.focusHandler = () => {
       ipcRenderer.send('editor:focused', true)
     }
@@ -60,6 +63,13 @@ export default class CodeEditor extends React.Component {
     this.searchState = null
 
     this.formatTable = () => this.handleFormatTable()
+
+    this.contextMenuHandler = function (editor, event) {
+      const menu = buildEditorContextMenu(editor, event)
+      if (menu != null) {
+        setTimeout(() => menu.popup(remote.getCurrentWindow()), 30)
+      }
+    }
   }
 
   handleSearch (msg) {
@@ -202,6 +212,7 @@ export default class CodeEditor extends React.Component {
     this.editor.on('blur', this.blurHandler)
     this.editor.on('change', this.changeHandler)
     this.editor.on('paste', this.pasteHandler)
+    this.editor.on('contextmenu', this.contextMenuHandler)
     eventEmitter.on('top:search', this.searchHandler)
 
     eventEmitter.emit('code:init')
@@ -217,6 +228,9 @@ export default class CodeEditor extends React.Component {
     CodeMirror.Vim.map('ZZ', ':q', 'normal')
     this.setState({ isReady: true })
     this.tableEditor = new TableEditor(new TextEditorInterface(this.editor))
+    if (this.props.spellCheck) {
+      this.editor.addPanel(this.createSpellCheckPanel(), {position: 'bottom'})
+    }
     eventEmitter.on('code:format-table', this.formatTable)
   }
 
@@ -305,9 +319,11 @@ export default class CodeEditor extends React.Component {
     this.editor.off('paste', this.pasteHandler)
     eventEmitter.off('top:search', this.searchHandler)
     this.editor.off('scroll', this.scrollHandler)
+    this.editor.off('contextmenu', this.contextMenuHandler)
     const editorTheme = document.getElementById('editorTheme')
     editorTheme.removeEventListener('load', this.loadStyleHandler)
 
+    spellcheck.setLanguage(null, spellcheck.SPELLCHECK_DISABLED)
     eventEmitter.off('code:format-table', this.formatTable)
   }
 
@@ -367,10 +383,11 @@ export default class CodeEditor extends React.Component {
     CodeMirror.autoLoadMode(this.editor, syntax.mode)
   }
 
-  handleChange (e) {
-    this.value = this.editor.getValue()
+  handleChange (editor, changeObject) {
+    spellcheck.handleChange(editor, changeObject)
+    this.value = editor.getValue()
     if (this.props.onChange) {
-      this.props.onChange(e)
+      this.props.onChange(editor)
     }
   }
 
@@ -589,6 +606,24 @@ export default class CodeEditor extends React.Component {
       />
     )
   }
+
+  createSpellCheckPanel () {
+    const panel = document.createElement('div')
+    panel.className = 'panel bottom'
+    const dropdown = document.createElement('select')
+    dropdown.title = 'Spellcheck'
+    dropdown.className = styles['spellcheck-select']
+    dropdown.addEventListener('change', (e) => spellcheck.setLanguage(this.editor, dropdown.value))
+    const options = spellcheck.getAvailableDictionaries()
+    for (const op of options) {
+      const option = document.createElement('option')
+      option.value = op.value
+      option.innerHTML = op.label
+      dropdown.appendChild(option)
+    }
+    panel.appendChild(dropdown)
+    return panel
+  }
 }
 
 CodeEditor.propTypes = {
@@ -599,7 +634,8 @@ CodeEditor.propTypes = {
   className: PropTypes.string,
   onBlur: PropTypes.func,
   onChange: PropTypes.func,
-  readOnly: PropTypes.bool
+  readOnly: PropTypes.bool,
+  spellCheck: PropTypes.bool
 }
 
 CodeEditor.defaultProps = {
@@ -609,5 +645,6 @@ CodeEditor.defaultProps = {
   fontSize: 14,
   fontFamily: 'Monaco, Consolas',
   indentSize: 4,
-  indentType: 'space'
+  indentType: 'space',
+  spellCheck: false
 }

browser/components/CodeEditor.styl

@@ -0,0 +1,6 @@
+.codeEditor-typo
+  text-decoration underline wavy red
+
+.spellcheck-select
+  border: none
+  text-decoration underline wavy red

browser/components/MarkdownEditor.js

@@ -268,6 +268,7 @@ class MarkdownEditor extends React.Component {
           fetchUrlTitle={config.editor.fetchUrlTitle}
           onChange={(e) => this.handleChange(e)}
           onBlur={(e) => this.handleBlur(e)}
+          spellCheck
         />
         <MarkdownPreview styleName={this.state.status === 'PREVIEW'
             ? 'preview'

browser/components/MarkdownSplitEditor.js

@@ -162,6 +162,7 @@ class MarkdownSplitEditor extends React.Component {
           noteKey={noteKey}
           onChange={this.handleOnChange.bind(this)}
           onScroll={this.handleScroll.bind(this)}
+          spellCheck
        />
         <div styleName='slider' style={{left: this.state.codeEditorWidthInPercent + '%'}} onMouseDown={e => this.handleMouseDown(e)} >
           <div styleName='slider-hitbox' />

browser/lib/contextMenuBuilder.js

@@ -0,0 +1,65 @@
+const {remote} = require('electron')
+const {Menu} = remote.require('electron')
+const spellcheck = require('./spellcheck')
+
+/**
+ * Creates the context menu that is shown when there is a right click in the editor of a (not-snippet) note.
+ * If the word is does not contains a spelling error (determined by the 'error style'), no suggestions for corrections are requested
+ * => they are not visible in the context menu
+ * @param editor CodeMirror editor
+ * @param {MouseEvent} event that has triggered the creation of the context menu
+ * @returns {Electron.Menu} The created electron context menu
+ */
+const buildEditorContextMenu = function (editor, event) {
+  if (editor == null || event == null || event.pageX == null || event.pageY == null) {
+    return null
+  }
+  const cursor = editor.coordsChar({left: event.pageX, top: event.pageY})
+  const wordRange = editor.findWordAt(cursor)
+  const word = editor.getRange(wordRange.anchor, wordRange.head)
+  const existingMarks = editor.findMarks(wordRange.anchor, wordRange.head) || []
+  let isMisspelled = false
+  for (const mark of existingMarks) {
+    if (mark.className === spellcheck.getCSSClassName()) {
+      isMisspelled = true
+      break
+    }
+  }
+  let suggestion = []
+  if (isMisspelled) {
+    suggestion = spellcheck.getSpellingSuggestion(word)
+  }
+
+  const selection = {
+    isMisspelled: isMisspelled,
+    spellingSuggestions: suggestion
+  }
+  const template = [{
+    role: 'cut'
+  }, {
+    role: 'copy'
+  }, {
+    role: 'paste'
+  }, {
+    role: 'selectall'
+  }]
+
+  if (selection.isMisspelled) {
+    const suggestions = selection.spellingSuggestions
+    template.unshift.apply(template, suggestions.map(function (suggestion) {
+      return {
+        label: suggestion,
+        click: function (suggestion) {
+          if (editor != null) {
+            editor.replaceRange(suggestion.label, wordRange.anchor, wordRange.head)
+          }
+        }
+      }
+    }).concat({
+      type: 'separator'
+    }))
+  }
+  return Menu.buildFromTemplate(template)
+}
+
+module.exports = buildEditorContextMenu

browser/lib/spellcheck.js

@@ -0,0 +1,229 @@
+import styles from '../components/CodeEditor.styl'
+import i18n from 'browser/lib/i18n'
+
+const Typo = require('typo-js')
+const _ = require('lodash')
+
+const CSS_ERROR_CLASS = 'codeEditor-typo'
+const SPELLCHECK_DISABLED = 'NONE'
+const DICTIONARY_PATH = '../dictionaries'
+const MILLISECONDS_TILL_LIVECHECK = 500
+
+let dictionary = null
+let self
+
+function getAvailableDictionaries () {
+  return [
+    {label: i18n.__('Disabled'), value: SPELLCHECK_DISABLED},
+    {label: i18n.__('English'), value: 'en_GB'},
+    {label: i18n.__('German'), value: 'de_DE'},
+    {label: i18n.__('French'), value: 'fr_FR'}
+  ]
+}
+
+/**
+ * Only to be used in the tests :)
+ */
+function setDictionaryForTestsOnly (newDictionary) {
+  dictionary = newDictionary
+}
+
+/**
+ * @description Initializes the spellcheck. It removes all existing marks of the current editor.
+ * If a language was given (i.e. lang !== this.SPELLCHECK_DISABLED) it will load the stated dictionary and use it to check the whole document.
+ * @param {Codemirror} editor CodeMirror-Editor
+ * @param {String} lang on of the values from getAvailableDictionaries()-Method
+ */
+function setLanguage (editor, lang) {
+  self = this
+  dictionary = null
+
+  if (editor == null) {
+    return
+  }
+
+  const existingMarks = editor.getAllMarks() || []
+  for (const mark of existingMarks) {
+    mark.clear()
+  }
+  if (lang !== SPELLCHECK_DISABLED) {
+    dictionary = new Typo(lang, false, false, {
+      dictionaryPath: DICTIONARY_PATH,
+      asyncLoad: true,
+      loadedCallback: () =>
+        checkWholeDocument(editor)
+    })
+  }
+}
+
+/**
+ * Checks the whole content of the editor for typos
+ * @param {Codemirror} editor CodeMirror-Editor
+ */
+function checkWholeDocument (editor) {
+  const lastLine = editor.lineCount() - 1
+  const textOfLastLine = editor.getLine(lastLine) || ''
+  const lastChar = textOfLastLine.length
+  const from = {line: 0, ch: 0}
+  const to = {line: lastLine, ch: lastChar}
+  checkMultiLineRange(editor, from, to)
+}
+
+/**
+ * Checks the given range for typos
+ * @param {Codemirror} editor CodeMirror-Editor
+ * @param {line, ch} from starting position of the spellcheck
+ * @param {line, ch} to end position of the spellcheck
+ */
+function checkMultiLineRange (editor, from, to) {
+  function sortRange (pos1, pos2) {
+    if (pos1.line > pos2.line || (pos1.line === pos2.line && pos1.ch > pos2.ch)) {
+      return {from: pos2, to: pos1}
+    }
+    return {from: pos1, to: pos2}
+  }
+
+  const {from: smallerPos, to: higherPos} = sortRange(from, to)
+  for (let l = smallerPos.line; l <= higherPos.line; l++) {
+    const line = editor.getLine(l) || ''
+    let w = 0
+    if (l === smallerPos.line) {
+      w = smallerPos.ch
+    }
+    let wEnd = line.length
+    if (l === higherPos.line) {
+      wEnd = higherPos.ch
+    }
+    while (w <= wEnd) {
+      const wordRange = editor.findWordAt({line: l, ch: w})
+      self.checkWord(editor, wordRange)
+      w += (wordRange.head.ch - wordRange.anchor.ch) + 1
+    }
+  }
+}
+
+/**
+ * @description Checks whether a certain range of characters in the editor (i.e. a word) contains a typo.
+ * If so the ranged will be marked with the class CSS_ERROR_CLASS.
+ * Note: Due to performance considerations, only words with more then 3 signs are checked.
+ * @param {Codemirror} editor CodeMirror-Editor
+ * @param wordRange Object specifying the range that should be checked.
+ * Having the following structure: <code>{anchor: {line: integer, ch: integer}, head: {line: integer, ch: integer}}</code>
+ */
+function checkWord (editor, wordRange) {
+  const word = editor.getRange(wordRange.anchor, wordRange.head)
+  if (word == null || word.length <= 3) {
+    return
+  }
+  if (!dictionary.check(word)) {
+    editor.markText(wordRange.anchor, wordRange.head, {className: styles[CSS_ERROR_CLASS]})
+  }
+}
+
+/**
+ * Checks the changes recently made (aka live check)
+ * @param {Codemirror} editor CodeMirror-Editor
+ * @param fromChangeObject codeMirror changeObject describing the start of the editing
+ * @param toChangeObject codeMirror changeObject describing the end of the editing
+ */
+function checkChangeRange (editor, fromChangeObject, toChangeObject) {
+  /**
+   * Calculate the smallest respectively largest position as a start, resp. end, position and return it
+   * @param start CodeMirror change object
+   * @param end CodeMirror change object
+   * @returns {{start: {line: *, ch: *}, end: {line: *, ch: *}}}
+   */
+  function getStartAndEnd (start, end) {
+    const possiblePositions = [start.from, start.to, end.from, end.to]
+    let smallest = start.from
+    let biggest = end.to
+    for (const currentPos of possiblePositions) {
+      if (currentPos.line < smallest.line || (currentPos.line === smallest.line && currentPos.ch < smallest.ch)) {
+        smallest = currentPos
+      }
+      if (currentPos.line > biggest.line || (currentPos.line === biggest.line && currentPos.ch > biggest.ch)) {
+        biggest = currentPos
+      }
+    }
+    return {start: smallest, end: biggest}
+  }
+
+  if (dictionary === null || editor == null) { return }
+
+  try {
+    const {start, end} = getStartAndEnd(fromChangeObject, toChangeObject)
+
+    // Expand the range to include words after/before whitespaces
+    start.ch = Math.max(start.ch - 1, 0)
+    end.ch = end.ch + 1
+
+    // clean existing marks
+    const existingMarks = editor.findMarks(start, end) || []
+    for (const mark of existingMarks) {
+      mark.clear()
+    }
+
+    self.checkMultiLineRange(editor, start, end)
+  } catch (e) {
+    console.info('Error during the spell check. It might be due to problems figuring out the range of the new text..', e)
+  }
+}
+
+function saveLiveSpellCheckFrom (changeObject) {
+  liveSpellCheckFrom = changeObject
+}
+let liveSpellCheckFrom
+const debouncedSpellCheckLeading = _.debounce(saveLiveSpellCheckFrom, MILLISECONDS_TILL_LIVECHECK, {
+  'leading': true,
+  'trailing': false
+})
+const debouncedSpellCheck = _.debounce(checkChangeRange, MILLISECONDS_TILL_LIVECHECK, {
+  'leading': false,
+  'trailing': true
+})
+
+/**
+ * Handles a keystroke. Buffers the input and performs a live spell check after a certain time. Uses _debounce from lodash to buffer the input
+ * @param {Codemirror} editor CodeMirror-Editor
+ * @param changeObject codeMirror changeObject
+ */
+function handleChange (editor, changeObject) {
+  debouncedSpellCheckLeading(changeObject)
+  debouncedSpellCheck(editor, liveSpellCheckFrom, changeObject)
+}
+
+/**
+ * Returns an array of spelling suggestions for the given (wrong written) word.
+ * Returns an empty array if the dictionary is null (=> spellcheck is disabled) or the given word was null
+ * @param word word to be checked
+ * @returns {String[]} Array of suggestions
+ */
+function getSpellingSuggestion (word) {
+  if (dictionary == null || word == null) {
+    return []
+  }
+  return dictionary.suggest(word)
+}
+
+/**
+ * Returns the name of the CSS class used for errors
+ */
+function getCSSClassName () {
+  return styles[CSS_ERROR_CLASS]
+}
+
+module.exports = {
+  DICTIONARY_PATH,
+  CSS_ERROR_CLASS,
+  SPELLCHECK_DISABLED,
+  getAvailableDictionaries,
+  setLanguage,
+  checkChangeRange,
+  handleChange,
+  getSpellingSuggestion,
+  checkWord,
+  checkMultiLineRange,
+  checkWholeDocument,
+  setDictionaryForTestsOnly,
+  getCSSClassName
+}