fix: copy raw markdown from chat messages

.changeset/copy-chat-raw-markdown.md

@@ -0,0 +1,5 @@
+---
+"@jmfederico/pi-web": patch
+---
+
+Copying selected rendered chat markdown now places the raw markdown source on the clipboard.

src/client/src/components/FormattedText.ts

@@ -9,7 +9,7 @@ export class FormattedText extends LitElement {
   @property() text = "";
 
   override render() {
-    return html`<div class="formatted" @click=${this.onFormattedClick}>${unsafeHTML(toSafeMarkdownHtml(this.text))}</div>`;
+    return html`<div class="formatted" @click=${this.onFormattedClick} @copy=${this.onFormattedCopy}>${unsafeHTML(toSafeMarkdownHtml(this.text))}</div>`;
   }
 
   override updated(): void {
@@ -48,6 +48,13 @@ export class FormattedText extends LitElement {
     void this.copyCode(code.textContent, button);
   };
 
+  private readonly onFormattedCopy = (event: ClipboardEvent): void => {
+    if (event.clipboardData === null || !hasSelectedText(currentSelection(this))) return;
+    event.clipboardData.setData("text/plain", this.text);
+    event.preventDefault();
+    event.stopPropagation();
+  };
+
   private async copyCode(text: string, button: HTMLButtonElement): Promise<void> {
     const ok = await writeClipboard(text);
     this.setCopyButtonState(button, ok ? "copied" : "failed");
@@ -67,6 +74,20 @@ export class FormattedText extends LitElement {
   static override styles = formattedTextStyles;
 }
 
+function currentSelection(element: Element): Selection | null {
+  const root = element.getRootNode();
+  if (typeof ShadowRoot !== "undefined" && root instanceof ShadowRoot && hasRootSelection(root)) return root.getSelection();
+  return element.ownerDocument.getSelection();
+}
+
+function hasRootSelection(root: Node): root is Node & { getSelection: () => Selection | null } {
+  return "getSelection" in root && typeof root.getSelection === "function";
+}
+
+function hasSelectedText(selection: Selection | null): boolean {
+  return selection !== null && !selection.isCollapsed && selection.toString() !== "";
+}
+
 async function writeClipboard(text: string): Promise<boolean> {
   try {
     await navigator.clipboard.writeText(text);