Change selection behaviour (#904)

* Change selection behaviour
* turn mouseup/mousedown events into click
* Remove `drawSelection()`
* Add custom cursor

web/cm_plugins/fenced_code.ts

@@ -6,7 +6,6 @@ import {
   decoratorStateField,
   invisibleDecoration,
   isCursorInRange,
-  shouldRenderAsCode,
 } from "./util.ts";
 import { MarkdownWidget } from "./markdown_widget.ts";
 import { IFrameWidget } from "./iframe_widget.ts";
@@ -18,7 +17,7 @@ export function fencedCodePlugin(editor: Client) {
     syntaxTree(state).iterate({
       enter({ from, to, name, node }) {
         if (name === "FencedCode") {
-          if (shouldRenderAsCode(state, [from, to])) {
+          if (isCursorInRange(state, [from, to])) {
             // Don't render the widget if the cursor is inside the fenced code
             return;
           }

web/cm_plugins/util.ts

@@ -24,10 +24,6 @@ export class LinkWidget extends WidgetType {
 
     // Mouse handling
     anchor.addEventListener("click", (e) => {
-      e.preventDefault();
-      e.stopPropagation();
-    });
-    anchor.addEventListener("mouseup", (e) => {
       if (e.button !== 0) {
         return;
       }
@@ -57,6 +53,13 @@ export class LinkWidget extends WidgetType {
     anchor.href = this.options.href || "#";
     return anchor;
   }
+
+  eq(other: WidgetType): boolean {
+    return other instanceof LinkWidget &&
+      this.options.text === other.options.text &&
+      this.options.href === other.options.href &&
+      this.options.title === other.options.title;
+  }
 }
 
 export class HtmlWidget extends WidgetType {
@@ -89,10 +92,8 @@ export function decoratorStateField(
     },
 
     update(value: DecorationSet, tr: Transaction) {
-      // if (tr.docChanged || tr.selection) {
+      if (tr.isUserEvent("select.pointer")) return value;
       return stateToDecoratorMapper(tr.state);
-      // }
-      // return value;
     },
 
     provide: (f) => EditorView.decorations.from(f),
@@ -161,21 +162,6 @@ export function isCursorInRange(state: EditorState, range: [number, number]) {
   );
 }
 
-export function shouldRenderAsCode(
-  state: EditorState,
-  range: [number, number],
-) {
-  const mainSelection = state.selection.main;
-  // When the selection is empty, we need to check if the cursor is inside the fenced code
-  if (mainSelection.empty) {
-    return checkRangeOverlap(range, [mainSelection.from, mainSelection.to]);
-  } else {
-    // If the selection is encompassing the fenced code we render as code, or vice versa
-    return checkRangeSubset([mainSelection.from, mainSelection.to], range) ||
-      checkRangeSubset(range, [mainSelection.from, mainSelection.to]);
-  }
-}
-
 /**
  * Decoration to simply hide anything.
  */

web/cm_plugins/wiki_link.ts

@@ -86,9 +86,11 @@ export function cleanWikiLinkPlugin(client: Client) {
                 callback: (e) => {
                   if (e.altKey) {
                     // Move cursor into the link
-                    return client.editorView.dispatch({
+                    client.editorView.dispatch({
                       selection: { anchor: from + firstMark.length },
                     });
+                    client.focus();
+                    return;
                   }
                   // Dispatch click event to navigate there without moving the cursor
                   const clickEvent: ClickEvent = {

web/editor_state.ts

@@ -19,14 +19,15 @@ import {
   LanguageSupport,
   syntaxHighlighting,
 } from "@codemirror/language";
-import { EditorState } from "@codemirror/state";
+import { EditorSelection, EditorState } from "@codemirror/state";
 import {
-  drawSelection,
   dropCursor,
   EditorView,
   highlightSpecialChars,
   KeyBinding,
   keymap,
+  layer,
+  RectangleMarker,
   ViewPlugin,
   ViewUpdate,
 } from "@codemirror/view";
@@ -115,7 +116,6 @@ export function createEditorState(
       codeCopyPlugin(client),
       highlightSpecialChars(),
       history(),
-      drawSelection(),
       dropCursor(),
       codeFolding({
         placeholderText: "…",
@@ -124,8 +124,46 @@ export function createEditorState(
       ...cleanModePlugins(client),
       EditorView.lineWrapping,
       plugLinter(client),
-      // lintGutter(),
-      //       gutters(),
+      // Taken from https://github.com/codemirror/view/blob/main/src/draw-selection.ts
+      layer({
+        above: true,
+        markers(view) {
+          const safari = /Apple Computer/.test(navigator.vendor);
+          const ios = safari &&
+            (/Mobile\/\w+/.test(navigator.userAgent) ||
+              navigator.maxTouchPoints > 2);
+
+          const { state } = view;
+          const cursors = [];
+          for (const r of state.selection.ranges) {
+            const prim = r == state.selection.main;
+            if (!r.empty || !prim || !ios) {
+              const className = prim
+                ? "cm-cursor cm-cursor-primary"
+                : "cm-cursor cm-cursor-secondary";
+              const cursor = r.empty
+                ? r
+                : EditorSelection.cursor(r.head, r.head > r.anchor ? -1 : 1);
+              for (
+                const piece of RectangleMarker.forRange(view, className, cursor)
+              ) cursors.push(piece);
+            }
+          }
+          return cursors;
+        },
+        update(update, dom) {
+          if (update.transactions.some((tr) => tr.selection)) {
+            dom.style.animationName = dom.style.animationName == "cm-blink"
+              ? "cm-blink2"
+              : "cm-blink";
+          }
+          return update.docChanged || update.selectionSet;
+        },
+        mount(dom) {
+          dom.style.animationDuration = "1200ms";
+        },
+        class: "cm-cursorLayer",
+      }),
       postScriptPrefacePlugin(client),
       lineWrapper([
         { selector: "ATXHeading1", class: "sb-line-h1" },
@@ -200,7 +238,7 @@ export function createEditorState(
           touchCount = 0;
         },
 
-        mousedown: (event: MouseEvent, view: EditorView) => {
+        click: (event: MouseEvent, view: EditorView) => {
           const pos = view.posAtCoords(event);
           if (event.button !== 0) {
             return;

web/editor_ui.tsx

@@ -60,6 +60,12 @@ export class MainUI {
         });
       }
     });
+
+    globalThis.addEventListener("mouseup", (_) => {
+      setTimeout(() => {
+        client.editorView.dispatch({});
+      })
+    });
   }
 
   ViewComponent() {

web/styles/colors.scss

@@ -4,7 +4,8 @@
   color: var(--root-color);
 }
 
-.cm-cursor {
+.cm-cursor,
+.cm-dropCursor {
   border-left: 1.2px solid var(--editor-caret-color) !important;
 }
 
@@ -174,9 +175,10 @@
 #sb-editor {
   .cm-content {
     font-family: var(--editor-font);
+    caret-color: transparent;
   }
 
-  .cm-selectionBackground {
+  ::selection {
     background-color: var(--editor-selection-background-color);
   }
 

web/styles/editor.scss

@@ -401,6 +401,10 @@
   }
 
   .sb-line-code-outside .sb-code-info {
+    &::selection {
+      background-color: transparent;
+    }
+
     display: block;
     float: right;
     font-size: 90%;
@@ -408,6 +412,10 @@
   }
 
   .sb-code-copy-button {
+    &::selection {
+      background-color: transparent;
+    }
+
     float: right;
     cursor: pointer;
     margin: 0 3px;