Encode code into url to make sharing snippets easy

resolves #253

web/src/components/IdeEditor/IdeEditor.js

@@ -1,10 +1,30 @@
-import { useContext } from 'react'
+import { useContext, useEffect } from 'react'
+import { isBrowser } from '@redwoodjs/prerender/browserUtils'
 import { IdeContext } from 'src/components/IdeToolbarNew'
 import Editor from '@monaco-editor/react'
 
 const IdeEditor = () => {
   const { state, dispatch } = useContext(IdeContext)
 
+  const scriptKey = 'encoded_script'
+  useEffect(() => {
+    // load code from hash if it's there
+    let hash
+    if (isBrowser) {
+      hash = window.location.hash
+    }
+    const [key, scriptBase64] = hash.slice(1).split('=')
+    if (key === scriptKey) {
+      const script = atob(scriptBase64)
+      dispatch({ type: 'updateCode', payload: script })
+    }
+  }, [])
+  useEffect(() => {
+    if (isBrowser) {
+      window.location.hash = ''
+    }
+  }, [state.code])
+
   function handleCodeChange(value, _event) {
     dispatch({ type: 'updateCode', payload: value })
   }