Allow pasting images (#472)

Fixes #283

src/hooks/useAttachments.ts

@@ -1,4 +1,4 @@
-import { useState, useRef } from "react";
+import React, { useState, useRef } from "react";
 
 export function useAttachments() {
   const [attachments, setAttachments] = useState<File[]>([]);
@@ -45,6 +45,50 @@ export function useAttachments() {
     setAttachments([]);
   };
 
+  const addAttachments = (files: File[]) => {
+    setAttachments((attachments) => [...attachments, ...files]);
+  };
+
+  const handlePaste = async (e: React.ClipboardEvent) => {
+    const clipboardData = e.clipboardData;
+    if (!clipboardData) return;
+
+    const items = Array.from(clipboardData.items);
+    const imageItems = items.filter((item) => item.type.startsWith("image/"));
+
+    if (imageItems.length > 0) {
+      e.preventDefault(); // Prevent default paste behavior for images
+
+      const imageFiles: File[] = [];
+      // Generate base timestamp once to avoid collisions
+      const baseTimestamp = new Date().toISOString().replace(/[:.]/g, "-");
+
+      for (let i = 0; i < imageItems.length; i++) {
+        const item = imageItems[i];
+        const file = item.getAsFile();
+        if (file) {
+          // Create a more descriptive filename with timestamp and counter
+          const extension = file.type.split("/")[1] || "png";
+          const filename =
+            imageItems.length === 1
+              ? `pasted-image-${baseTimestamp}.${extension}`
+              : `pasted-image-${baseTimestamp}-${i + 1}.${extension}`;
+
+          const newFile = new File([file], filename, {
+            type: file.type,
+          });
+          imageFiles.push(newFile);
+        }
+      }
+
+      if (imageFiles.length > 0) {
+        addAttachments(imageFiles);
+        // Show a brief toast or indication that image was pasted
+        console.log(`Pasted ${imageFiles.length} image(s) from clipboard`);
+      }
+    }
+  };
+
   return {
     attachments,
     fileInputRef,
@@ -56,5 +100,6 @@ export function useAttachments() {
     handleDragLeave,
     handleDrop,
     clearAttachments,
+    handlePaste,
   };
 }