Add experimental highlighting to composer textarea

package-lock.json

@@ -25,6 +25,7 @@
         "react-hotkeys-hook": "~4.3.7",
         "react-intersection-observer": "~9.4.2",
         "react-router-dom": "6.6.2",
+        "rich-textarea": "~0.19.5",
         "string-length": "~5.0.1",
         "swiped-events": "~1.1.7",
         "toastify-js": "~1.12.0",
@@ -3200,6 +3201,20 @@
         "@babel/core": "^7.12.10"
       }
     },
+    "node_modules/babel-runtime": {
+      "version": "4.7.4",
+      "resolved": "https://registry.npmjs.org/babel-runtime/-/babel-runtime-4.7.4.tgz",
+      "integrity": "sha512-0gnK56hiHkbUCwqtaiK15MAsnNxI8T7aOBYUyoAYyNxWs86ExL0NNTDhn0eDO/AIhJf0oXMgV5+1wfSLQ/FMyw==",
+      "dependencies": {
+        "core-js": "^0.6.1"
+      }
+    },
+    "node_modules/babel-runtime/node_modules/core-js": {
+      "version": "0.6.1",
+      "resolved": "https://registry.npmjs.org/core-js/-/core-js-0.6.1.tgz",
+      "integrity": "sha512-ANdRS9QdyvvVCqMD7gvDhgI5T+/t5FELQB1ZLN94oCDXTJLwt4Q1o6Nbc1wnVrhl6QPyJ5mv0k8hMCdAFLNbLg==",
+      "deprecated": "core-js@<3.23.3 is no longer maintained and not recommended for usage due to the number of issues. Because of the V8 engine whims, feature detection in old core-js versions could cause a slowdown up to 100x even if nothing is polyfilled. Some versions have web compatibility issues. Please, upgrade your dependencies to the actual version of core-js."
+    },
     "node_modules/balanced-match": {
       "version": "1.0.2",
       "resolved": "https://registry.npmjs.org/balanced-match/-/balanced-match-1.0.2.tgz",
@@ -5733,6 +5748,14 @@
         "safe-buffer": "^5.1.0"
       }
     },
+    "node_modules/range-at-index": {
+      "version": "1.0.4",
+      "resolved": "https://registry.npmjs.org/range-at-index/-/range-at-index-1.0.4.tgz",
+      "integrity": "sha512-Aob2FK5jL0cCKvIzA0tuRrdsSXTvxLY5p9dr7GrLY31NwKtUk5EhgHwcKi0kbUacJukGVRglLi6MEqBHB4NHMA==",
+      "dependencies": {
+        "babel-runtime": "4.7.4"
+      }
+    },
     "node_modules/react": {
       "version": "18.2.0",
       "resolved": "https://registry.npmjs.org/react/-/react-18.2.0.tgz",
@@ -5957,6 +5980,18 @@
         "node": ">=0.10.0"
       }
     },
+    "node_modules/rich-textarea": {
+      "version": "0.19.5",
+      "resolved": "https://registry.npmjs.org/rich-textarea/-/rich-textarea-0.19.5.tgz",
+      "integrity": "sha512-jGzE84BUs0VKLTEIdJaQcToQjRxYO1aNRnPNtnGupkwKWl59dCpp5EWWi5qxU1JMjPtKOBFSSynYG0srr71TJw==",
+      "dependencies": {
+        "range-at-index": "^1.0.4",
+        "use-sync-external-store": "^1.2.0"
+      },
+      "peerDependencies": {
+        "react": ">=16.14.0"
+      }
+    },
     "node_modules/rollup": {
       "version": "3.12.1",
       "resolved": "https://registry.npmjs.org/rollup/-/rollup-3.12.1.tgz",
@@ -9146,6 +9181,21 @@
       "dev": true,
       "requires": {}
     },
+    "babel-runtime": {
+      "version": "4.7.4",
+      "resolved": "https://registry.npmjs.org/babel-runtime/-/babel-runtime-4.7.4.tgz",
+      "integrity": "sha512-0gnK56hiHkbUCwqtaiK15MAsnNxI8T7aOBYUyoAYyNxWs86ExL0NNTDhn0eDO/AIhJf0oXMgV5+1wfSLQ/FMyw==",
+      "requires": {
+        "core-js": "^0.6.1"
+      },
+      "dependencies": {
+        "core-js": {
+          "version": "0.6.1",
+          "resolved": "https://registry.npmjs.org/core-js/-/core-js-0.6.1.tgz",
+          "integrity": "sha512-ANdRS9QdyvvVCqMD7gvDhgI5T+/t5FELQB1ZLN94oCDXTJLwt4Q1o6Nbc1wnVrhl6QPyJ5mv0k8hMCdAFLNbLg=="
+        }
+      }
+    },
     "balanced-match": {
       "version": "1.0.2",
       "resolved": "https://registry.npmjs.org/balanced-match/-/balanced-match-1.0.2.tgz",
@@ -10892,6 +10942,14 @@
         "safe-buffer": "^5.1.0"
       }
     },
+    "range-at-index": {
+      "version": "1.0.4",
+      "resolved": "https://registry.npmjs.org/range-at-index/-/range-at-index-1.0.4.tgz",
+      "integrity": "sha512-Aob2FK5jL0cCKvIzA0tuRrdsSXTvxLY5p9dr7GrLY31NwKtUk5EhgHwcKi0kbUacJukGVRglLi6MEqBHB4NHMA==",
+      "requires": {
+        "babel-runtime": "4.7.4"
+      }
+    },
     "react": {
       "version": "18.2.0",
       "resolved": "https://registry.npmjs.org/react/-/react-18.2.0.tgz",
@@ -11057,6 +11115,15 @@
       "integrity": "sha512-U9nH88a3fc/ekCF1l0/UP1IosiuIjyTh7hBvXVMHYgVcfGvt897Xguj2UOLDeI5BG2m7/uwyaLVT6fbtCwTyzw==",
       "dev": true
     },
+    "rich-textarea": {
+      "version": "0.19.5",
+      "resolved": "https://registry.npmjs.org/rich-textarea/-/rich-textarea-0.19.5.tgz",
+      "integrity": "sha512-jGzE84BUs0VKLTEIdJaQcToQjRxYO1aNRnPNtnGupkwKWl59dCpp5EWWi5qxU1JMjPtKOBFSSynYG0srr71TJw==",
+      "requires": {
+        "range-at-index": "^1.0.4",
+        "use-sync-external-store": "^1.2.0"
+      }
+    },
     "rollup": {
       "version": "3.12.1",
       "resolved": "https://registry.npmjs.org/rollup/-/rollup-3.12.1.tgz",

package.json

@@ -27,6 +27,7 @@
     "react-hotkeys-hook": "~4.3.7",
     "react-intersection-observer": "~9.4.2",
     "react-router-dom": "6.6.2",
+    "rich-textarea": "~0.19.5",
     "string-length": "~5.0.1",
     "swiped-events": "~1.1.7",
     "toastify-js": "~1.12.0",

src/components/compose.css

@@ -466,6 +466,12 @@
   vertical-align: middle;
 }
 
+.compose-highlight,
+.compose-link {
+  color: var(--link-color);
+  background-color: transparent;
+}
+
 @media (min-width: 50em) {
   #media-sheet main {
     flex-direction: row;

src/components/compose.jsx

@@ -5,6 +5,7 @@ import equal from 'fast-deep-equal';
 import { forwardRef } from 'preact/compat';
 import { useEffect, useRef, useState } from 'preact/hooks';
 import { useHotkeys } from 'react-hotkeys-hook';
+import { createRegexRenderer, RichTextarea } from 'rich-textarea';
 import stringLength from 'string-length';
 import { uid } from 'uid/single';
 import { useDebouncedCallback } from 'use-debounce';
@@ -1038,6 +1039,28 @@ function Compose({
   );
 }
 
+const HIGHLIGHT_REG = /(#|@|:)[\p{L}\p{M}\p{N}\p{Pc}_@\.]+:?/gu;
+const highlightRenderer = createRegexRenderer([
+  [
+    HIGHLIGHT_REG,
+    ({ value }) => {
+      const first = value[0];
+      const last = value[value.length - 1] === ':' ? ':' : '';
+      const rest = value.slice(1, last ? -1 : undefined);
+      return (
+        <>
+          <mark class="compose-highlight">{first}</mark>
+          {rest}
+          {last && <mark class="compose-highlight">{last}</mark>}
+        </>
+      );
+    },
+  ],
+  [urlRegexObj, (props) => <mark class="compose-link" {...props} />],
+]);
+
+const RICH_TEXTAREA = true;
+
 const Textarea = forwardRef((props, ref) => {
   const { masto } = api();
   const [text, setText] = useState(ref.current?.value || '');
@@ -1216,33 +1239,39 @@ const Textarea = forwardRef((props, ref) => {
     };
   }, []);
 
-  return (
+  const fieldProps = {
-    <text-expander ref={textExpanderRef} keys="@ # :">
+    autoCapitalize: 'sentences',
-      <textarea
+    autoComplete: 'on',
-        autoCapitalize="sentences"
+    autoCorrect: 'on',
-        autoComplete="on"
+    spellCheck: 'true',
-        autoCorrect="on"
+    dir: 'auto',
-        spellCheck="true"
+    rows: '6',
-        dir="auto"
+    cols: '50',
-        rows="6"
+    ...textareaProps,
-        cols="50"
+    ref,
-        {...textareaProps}
+    name: 'status',
-        ref={ref}
+    value: text,
-        name="status"
+    onInput: (e) => {
-        value={text}
-        onInput={(e) => {
       const { scrollHeight, offsetHeight, clientHeight, value } = e.target;
       setText(value);
       const offset = offsetHeight - clientHeight;
       e.target.style.height = value ? scrollHeight + offset + 'px' : null;
       props.onInput?.(e);
-        }}
+    },
-        style={{
+    style: {
       width: '100%',
       height: '4em',
       '--text-weight': (1 + charCount / 140).toFixed(1) || 1,
-        }}
+    },
-      />
+  };
+
+  return (
+    <text-expander ref={textExpanderRef} keys="@ # :">
+      {RICH_TEXTAREA ? (
+        <RichTextarea {...fieldProps}>{highlightRenderer}</RichTextarea>
+      ) : (
+        <textarea {...fieldProps} />
+      )}
     </text-expander>
   );
 });