Server to client: diffs

3 files changed, 44 insertions, 18 deletions

diff --git a/html/whiteboard.js b/html/whiteboard.js
index 58023fe..3e09621 100644
--- a/html/whiteboard.js
+++ b/html/whiteboard.js
@@ -48,6 +48,26 @@ function on_getfile(data, rev, pos)
 	textAreaSetPos("board", pos);
 }
 
+function on_getdiff(diff, rev)
+{
+        if (rev != revision + 1)
+         alert("Revision skipped: " + rev + " after " + revision);
+
+	var board = document.getElementById("board");
+
+        var old_version_ptr = allocateUTF8(board.value);
+        var diff_ptr = allocateUTF8(new XMLSerializer().serializeToString(diff));
+        var new_version_ptr = Module._diff_apply(old_version_ptr, diff_ptr);
+        var data = UTF8ToString(new_version_ptr);
+	board.value = data;
+        _free(old_version_ptr);
+        _free(new_version_ptr);
+        _free(diff_ptr);
+
+	revision = rev;
+        baseline = data;
+}
+
 function on_getpos(pos)
 {
 	textAreaSetPos("board", pos);
@@ -88,6 +108,9 @@ function on_message(e) {
 		on_getfile(xmlDocument.getElementsByTagName("data")[0].textContent,
 			   parseInt(xmlDocument.getElementsByTagName("revision")[0].textContent),
 		           parseInt(xmlDocument.getElementsByTagName("pos")[0].textContent));
+        } else if (type == "getdiff") {
+		on_getdiff(xmlDocument.getElementsByTagName("diff")[0],
+			   parseInt(xmlDocument.getElementsByTagName("revision")[0].textContent));
 	} else if (type == "getpos") {
 		on_getpos(parseInt(xmlDocument.getElementsByTagName("pos")[0].textContent));
 	} else if (type == "modify") {
@@ -216,10 +239,6 @@ function on_input()
 	idElement.appendChild(document.createTextNode(get_id()));
 	requestElement.appendChild(idElement);
 
-	var dataElement = xmlDocument.createElement("data");
-	dataElement.appendChild(document.createTextNode(document.getElementById("board").value));
-	requestElement.appendChild(dataElement);
-
         baseline_candidate = document.getElementById("board").value;
 
 	var revisionElement = xmlDocument.createElement("baserev");
diff --git a/whiteboard.cpp b/whiteboard.cpp
index 059571d..35ae30b 100644
--- a/whiteboard.cpp
+++ b/whiteboard.cpp
@@ -83,33 +83,39 @@ void Whiteboard::storage_cleanup()
  }
 }
 
-std::string make_xml(const std::initializer_list<std::pair<std::string, std::string>>& key_values)
+pt::ptree make_ptree(const std::initializer_list<std::pair<std::string, std::string>>& key_values)
 {
- pt::ptree xml;
+ pt::ptree ptree;
  for (const auto& i: key_values) {
-  xml.put(fmt::format("serverinfo.{}", i.first), i.second);
+  ptree.put(fmt::format("serverinfo.{}", i.first), i.second);
  }
 
- return Reichwein::XML::plain_xml(xml);
+ return ptree;
+}
+
+std::string make_xml(const std::initializer_list<std::pair<std::string, std::string>>& key_values)
+{
+ pt::ptree ptree{make_ptree(key_values)};
+ return Reichwein::XML::plain_xml(ptree);
 }
 
-void Whiteboard::notify_other_connections_file(Whiteboard::connection& c, const std::string& id)
+void Whiteboard::notify_other_connections_diff(Whiteboard::connection& c, const std::string& id, const Diff& diff)
 {
  std::for_each(m_registry.begin(id), m_registry.end(id), [&](const Whiteboard::connection& ci)
                {
                 if (c != ci) {
                  boost::beast::flat_buffer buffer;
-                 boost::beast::ostream(buffer) << make_xml({
-                   {"type", "getfile"},
-                   {"data", m_storage->getDocument(id)},
-                   {"revision", std::to_string(m_storage->getRevision(id)) },
-                   {"pos", std::to_string(m_storage->getCursorPos(id)) }
-                   });
+                 pt::ptree ptree {make_ptree({
+                   {"type", "getdiff"},
+                   {"revision", std::to_string(m_storage->getRevision(id)) }
+                   })};
+                 ptree.put_child("serverinfo.diff", diff.get_structure().get_child("diff"));
+                 boost::beast::ostream(buffer) << Reichwein::XML::plain_xml(ptree);
                  std::lock_guard<std::mutex> lock(m_websocket_mutex);
                  try {
                   ci->write(buffer.data());
                  } catch (const std::exception& ex) {
-                  std::cerr << "Warning: Notify getfile write for " << ci << " not possible, id " << id << std::endl;
+                  std::cerr << "Warning: Notify getdiff write for " << ci << " not possible, id " << id << std::endl;
                   m_registry.dump();
                  }
                 }
@@ -165,7 +171,7 @@ std::string Whiteboard::handle_request(Whiteboard::connection& c, const std::str
 
    m_storage->setDocument(id, data);
    m_registry.setId(c, id);
-   notify_other_connections_file(c, id);
+   notify_other_connections_diff(c, id, d);
    
    int pos {xml.get<int>("request.pos")};
    if (m_storage->getCursorPos(id) != pos) {
diff --git a/whiteboard.h b/whiteboard.h
index 818fcfe..c000e36 100644
--- a/whiteboard.h
+++ b/whiteboard.h
@@ -7,6 +7,7 @@
 
 #include <boost/asio/ip/tcp.hpp>
 
+#include "diff.h"
 #include "config.h"
 #include "connectionregistry.h"
 #include "storage.h"
@@ -27,7 +28,7 @@ private:
  
  using connection = std::shared_ptr<boost::beast::websocket::stream<boost::asio::ip::tcp::socket>>;
  std::string handle_request(connection& c, const std::string& request);
- void notify_other_connections_file(connection& c, const std::string& id); // notify all other id-related connections about changes
+ void notify_other_connections_diff(connection& c, const std::string& id, const Diff& diff); // notify all other id-related connections about changes
  void notify_other_connections_pos(connection& c, const std::string& id); // notify all other id-related connections about changes
  void do_session(boost::asio::ip::tcp::socket socket);
  void storage_cleanup();