Enable re-reading and sending changed files without input dialog

Author: jdtsmith

webrepl.html

@@ -59,7 +59,7 @@
     <strong>Send a file</strong>
     <input type="file" id="put-file-select" />
     <div id="put-file-list"></div>
-    <input type="button" value="Send to device" id="put-file-button" onclick="put_file(); return false;" />
+    <input type="button" value="Send to device" id="put-file-button" onclick="reread_and_put_file(); return false;" />
   </div>
 
   <div class="file-box">
@@ -85,7 +85,9 @@
 var connected = false;
 var binary_state = 0;
 var put_file_name = null;
+var put_file_lastMod = null;
 var put_file_data = null;
+var put_file_reader = null;
 var get_file_name = null;
 var get_file_data = null;
 
@@ -339,23 +341,61 @@
     ws.send(rec);
 }
 
+function reread_and_put_file() {
+    if(put_file_reader) put_file_reader(()=>{put_file()});
+}
+
 function handle_put_file_select(evt) {
     // The event holds a FileList object which is a list of File objects,
     // but we only support single file selection at the moment.
     var files = evt.target.files;
-
+    var file = files[0];
+    
     // Get the file info and load its data.
-    var f = files[0];
-    put_file_name = f.name;
+    put_file_name = file.name;
+    put_file_lastMod = -1;	// reset
+    put_file_reader = (callback) => {
+	read_put_file(file,callback);
+    }
+    document.getElementById('put-file-button').disabled = false;
+    put_file_message('');
+}
+
+function put_file_changed(file) {
+    if (file && put_file_lastMod && file.lastModified !== put_file_lastMod) {
+	var initial = put_file_lastMod===-1; // Initial load?
+	put_file_lastMod = file.lastModified;
+	console.log("Updating lastMod to ",put_file_lastMod);
+	return initial ? 1 : true;
+    }
+    return false;
+}
+
+function put_file_message(msg, suffix) {
+    if (suffix) msg=escape(put_file_name) + ' - ' + put_file_data.length + ' bytes ' +msg;
+    document.getElementById('put-file-list').innerHTML = msg;
+}
+
+function read_put_file(file,callback) {
+    var changed = put_file_changed(file);
+    if (!changed) {
+	update_file_status("[Unchanged]",true);
+	return;
+    }
     var reader = new FileReader();
     reader.onload = function(e) {
         put_file_data = new Uint8Array(e.target.result);
-        document.getElementById('put-file-list').innerHTML = '' + escape(put_file_name) + ' - ' + put_file_data.length + ' bytes';
-        document.getElementById('put-file-button').disabled = false;
+	put_file_message(changed === true ? "[Changed]" : "",true);
+	if(changed && callback) callback();
     };
-    reader.readAsArrayBuffer(f);
+    reader.onerror= function(e) {
+	update_file_status("[Error: Must Choose File Again]")
+	console.log("Error Reading File " + escape(put_file_name) + ': ',e.target.error);
+    }
+    reader.readAsArrayBuffer(file);
 }
-
+  
+  
 document.getElementById('put-file-select').addEventListener('click', function(){
     this.value = null;
 }, false);