Merge pull request #2979 from overleaf/ta-outline-parser-v2

Improve Outline Parser

GitOrigin-RevId: 1774ac1055efc8c2b899396e4f56b6993438daad

services/web/frontend/js/ide/outline/OutlineParser.js

@@ -1,32 +1,97 @@
 const COMMAND_LEVELS = {
-  section: 0,
-  subsection: 1,
-  subsubsection: 2
+  book: 10,
+  part: 20,
+  chapter: 30,
+  section: 40,
+  subsection: 50,
+  subsubsection: 60,
+  paragraph: 70,
+  subparagraph: 80
 }
 
+/*
+ *
+ * RegExp matcher parts:
+ *
+ * REGEX_START: begining of line, any number of spaces, double \ (required)
+ * REGEX_COMMAND: any of the listed commands (required)
+ * REGEX_SPACING: spaces and * between groups (optional)
+ * REGEX_SHORT_TITLE: a text between square brackets (optional)
+ * REGEX_TITLE: a text between curly brackets (required)
+ *
+ */
+const REGEX_START = '^\\s*\\\\'
+const REGEX_COMMAND = `(${Object.keys(COMMAND_LEVELS).join('|')})`
+const REGEX_SPACING = '\\s?\\*?\\s?'
+const REGEX_SHORT_TITLE = '(\\[([^\\]]+)\\])?'
+const REGEX_TITLE = '{(.*)}'
+const MATCHER = new RegExp(
+  `${REGEX_START}${REGEX_COMMAND}${REGEX_SPACING}${REGEX_SHORT_TITLE}${REGEX_SPACING}${REGEX_TITLE}`
+)
+
 function matchOutline(content) {
   const lines = content.split('\n')
   const flatOutline = []
   lines.forEach((line, lineId) => {
-    const match = line.match(/\\(?<command>[sub]*section)\{(?<title>[^}]+)\}/)
+    const match = line.match(MATCHER)
     if (!match) return
-    const {
-      groups: { command, title }
-    } = match
+    const [, command, , shortTitle, title] = match
+
     flatOutline.push({
       line: lineId + 1,
-      title,
+      title: matchDisplayTitle(shortTitle || title),
       level: COMMAND_LEVELS[command]
     })
   })
   return flatOutline
 }
 
+const DISPLAY_TITLE_REGEX = new RegExp('([^\\\\]*)\\\\([^{]+){([^}]+)}(.*)')
+/*
+ * Attempt to improve the display of the outline title for titles with commands.
+ * Either skip the command (for labels) or display the command's content instead
+ * of the entire command.
+ *
+ * e.g. "Label \\label{foo} between" => "Label  between"
+ * e.g. "TT \\texttt{Bar}" => "TT Bar"
+ *
+ */
+function matchDisplayTitle(title) {
+  const closingBracketPosition = title.indexOf('}')
+  if (closingBracketPosition < 0) {
+    // simple title (no commands)
+    return title
+  }
+
+  const titleMatch = title.match(DISPLAY_TITLE_REGEX)
+  if (!titleMatch) {
+    // no contained commands; strip everything after the first closing bracket
+    return title.substring(0, closingBracketPosition)
+  }
+
+  const [, textBefore, command, commandContent, textAfter] = titleMatch
+  if (command === 'label') {
+    // label: don't display them at all
+    title = `${textBefore}${textAfter}`
+  } else {
+    // display the content of the command. Works well for formatting commands
+    title = `${textBefore}${commandContent}${textAfter}`
+  }
+
+  return title
+}
+
 function nestOutline(flatOutline) {
   let parentOutlines = {}
   let nestedOutlines = []
   flatOutline.forEach(outline => {
-    const parentOutline = parentOutlines[outline.level - 1]
+    const parentOutlineLevels = Object.keys(parentOutlines)
+
+    // find the nearest parent outline
+    const nearestParentLevel = parentOutlineLevels
+      .reverse()
+      .find(level => level < outline.level)
+    const parentOutline = parentOutlines[nearestParentLevel]
     if (!parentOutline) {
       // top level
       nestedOutlines.push(outline)
@@ -37,7 +102,13 @@ function nestOutline(flatOutline) {
       // push outline to node
       parentOutline.children.push(outline)
     }
+
+    // store the outline as new parent at its level and forget lower-level
+    // outlines (if any) as they shouldn't get any children anymore
     parentOutlines[outline.level] = outline
+    parentOutlineLevels
+      .filter(level => level > outline.level)
+      .forEach(level => delete parentOutlines[level])
   })
   return nestedOutlines
 }