From 9030bc5d58b6ba351645f34e45fd08635e9ab62b Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Micha=C5=82=20Ska=C5=82ka?=
 <39538890+Skalakid@users.noreply.github.com>
Date: Tue, 7 Jan 2025 00:50:52 -0800
Subject: [PATCH] Fix custom parsing on the web (#585)

---
 src/parseExpensiMark.ts      | 40 +-------------------------
 src/rangeUtils.ts            | 56 ++++++++++++++++++++++++++++++++++++
 src/web/utils/parserUtils.ts | 19 +++---------
 3 files changed, 61 insertions(+), 54 deletions(-)
 create mode 100644 src/rangeUtils.ts

diff --git a/src/parseExpensiMark.ts b/src/parseExpensiMark.ts
index 7657efd9..7073d349 100644
--- a/src/parseExpensiMark.ts
+++ b/src/parseExpensiMark.ts
@@ -6,6 +6,7 @@ import {unescapeText} from 'expensify-common/dist/utils';
 import {decode} from 'html-entities';
 import type {WorkletFunction} from 'react-native-reanimated/lib/typescript/commonTypes';
 import type {MarkdownType, MarkdownRange} from './commonTypes';
+import {groupRanges, sortRanges} from './rangeUtils';
 
 function isWeb() {
   return Platform.OS === 'web';
@@ -233,45 +234,6 @@ function parseTreeToTextAndRanges(tree: StackItem): [string, MarkdownRange[]] {
   return [text, ranges];
 }
 
-// getTagPriority returns a priority for a tag, higher priority means the tag should be processed first
-function getTagPriority(tag: string) {
-  switch (tag) {
-    case 'blockquote':
-      return 2;
-    case 'h1':
-      return 1;
-    default:
-      return 0;
-  }
-}
-
-function sortRanges(ranges: MarkdownRange[]) {
-  // sort ranges by start position, then by length, then by tag hierarchy
-  return ranges.sort((a, b) => a.start - b.start || b.length - a.length || getTagPriority(b.type) - getTagPriority(a.type) || 0);
-}
-
-function groupRanges(ranges: MarkdownRange[]) {
-  const lastVisibleRangeIndex: {[key in MarkdownType]?: number} = {};
-
-  return ranges.reduce((acc, range) => {
-    const start = range.start;
-    const end = range.start + range.length;
-
-    const rangeWithSameStyleIndex = lastVisibleRangeIndex[range.type];
-    const sameStyleRange = rangeWithSameStyleIndex !== undefined ? acc[rangeWithSameStyleIndex] : undefined;
-
-    if (sameStyleRange && sameStyleRange.start <= start && sameStyleRange.start + sameStyleRange.length >= end && range.length > 1) {
-      // increment depth of overlapping range
-      sameStyleRange.depth = (sameStyleRange.depth || 1) + 1;
-    } else {
-      lastVisibleRangeIndex[range.type] = acc.length;
-      acc.push(range);
-    }
-
-    return acc;
-  }, [] as MarkdownRange[]);
-}
-
 function parseExpensiMark(markdown: string): MarkdownRange[] {
   if (markdown.length > MAX_PARSABLE_LENGTH) {
     return [];
diff --git a/src/rangeUtils.ts b/src/rangeUtils.ts
new file mode 100644
index 00000000..dcfb913f
--- /dev/null
+++ b/src/rangeUtils.ts
@@ -0,0 +1,56 @@
+import type {MarkdownRange, MarkdownType} from './commonTypes';
+
+// getTagPriority returns a priority for a tag, higher priority means the tag should be processed first
+function getTagPriority(tag: string) {
+  switch (tag) {
+    case 'blockquote':
+      return 2;
+    case 'h1':
+      return 1;
+    default:
+      return 0;
+  }
+}
+
+function sortRanges(ranges: MarkdownRange[]) {
+  // sort ranges by start position, then by length, then by tag hierarchy
+  return ranges.sort((a, b) => a.start - b.start || b.length - a.length || getTagPriority(b.type) - getTagPriority(a.type) || 0);
+}
+
+function groupRanges(ranges: MarkdownRange[]) {
+  const lastVisibleRangeIndex: {[key in MarkdownType]?: number} = {};
+
+  return ranges.reduce((acc, range) => {
+    const start = range.start;
+    const end = range.start + range.length;
+
+    const rangeWithSameStyleIndex = lastVisibleRangeIndex[range.type];
+    const sameStyleRange = rangeWithSameStyleIndex !== undefined ? acc[rangeWithSameStyleIndex] : undefined;
+
+    if (sameStyleRange && sameStyleRange.start <= start && sameStyleRange.start + sameStyleRange.length >= end && range.length > 1) {
+      // increment depth of overlapping range
+      sameStyleRange.depth = (sameStyleRange.depth || 1) + 1;
+    } else {
+      lastVisibleRangeIndex[range.type] = acc.length;
+      acc.push(range);
+    }
+
+    return acc;
+  }, [] as MarkdownRange[]);
+}
+
+function ungroupRanges(ranges: MarkdownRange[]): MarkdownRange[] {
+  const ungroupedRanges: MarkdownRange[] = [];
+  ranges.forEach((range) => {
+    if (!range.depth) {
+      ungroupedRanges.push(range);
+    }
+    const {depth, ...rangeWithoutDepth} = range;
+    Array.from({length: depth!}).forEach(() => {
+      ungroupedRanges.push(rangeWithoutDepth);
+    });
+  });
+  return ungroupedRanges;
+}
+
+export {sortRanges, groupRanges, ungroupRanges};
diff --git a/src/web/utils/parserUtils.ts b/src/web/utils/parserUtils.ts
index 419ed780..694b6601 100644
--- a/src/web/utils/parserUtils.ts
+++ b/src/web/utils/parserUtils.ts
@@ -6,6 +6,7 @@ import {getCurrentCursorPosition, moveCursorToEnd, setCursorPosition} from './cu
 import {addStyleToBlock, extendBlockStructure, getFirstBlockMarkdownRange, isBlockMarkdownType} from './blockUtils';
 import type {InlineImagesInputProps, MarkdownRange} from '../../commonTypes';
 import {getAnimationCurrentTimes, updateAnimationsTime} from './animationUtils';
+import {sortRanges, ungroupRanges} from '../../rangeUtils';
 
 type Paragraph = {
   text: string;
@@ -14,20 +15,6 @@ type Paragraph = {
   markdownRanges: MarkdownRange[];
 };
 
-function ungroupRanges(ranges: MarkdownRange[]): MarkdownRange[] {
-  const ungroupedRanges: MarkdownRange[] = [];
-  ranges.forEach((range) => {
-    if (!range.depth) {
-      ungroupedRanges.push(range);
-    }
-    const {depth, ...rangeWithoutDepth} = range;
-    Array.from({length: depth!}).forEach(() => {
-      ungroupedRanges.push(rangeWithoutDepth);
-    });
-  });
-  return ungroupedRanges;
-}
-
 function splitTextIntoLines(text: string): Paragraph[] {
   let lineStartIndex = 0;
   const lines: Paragraph[] = text.split('\n').map((line) => {
@@ -167,7 +154,9 @@ function parseRangesToHTMLNodes(
     return {dom: rootElement, tree: rootNode};
   }
 
-  const markdownRanges = ungroupRanges(ranges);
+  // Sort all ranges by start position, length, and by tag hierarchy so the styles and text are applied in correct order
+  const sortedRanges = sortRanges(ranges);
+  const markdownRanges = ungroupRanges(sortedRanges);
   lines = mergeLinesWithMultilineTags(lines, markdownRanges);
 
   let lastRangeEndIndex = 0;