Step 117: session persistence

editor/src/SessionManager.h

@@ -0,0 +1,68 @@
+#pragma once
+// Step 117: Session persistence
+
+#include <string>
+#include <vector>
+#include <nlohmann/json.hpp>
+
+struct SessionBufferState {
+    std::string path;
+    std::string language;
+    std::string mode;
+    int cursorLine = 1;
+    int cursorCol = 1;
+    std::vector<int> foldedLines;
+};
+
+struct SessionData {
+    std::string workspaceRoot;
+    std::string activePath;
+    std::string layoutPreset;
+    std::string imguiIni;
+    std::vector<SessionBufferState> buffers;
+};
+
+inline nlohmann::json sessionToJson(const SessionData& session) {
+    nlohmann::json j;
+    j["workspaceRoot"] = session.workspaceRoot;
+    j["activePath"] = session.activePath;
+    j["layoutPreset"] = session.layoutPreset;
+    j["imguiIni"] = session.imguiIni;
+    j["buffers"] = nlohmann::json::array();
+    for (const auto& b : session.buffers) {
+        nlohmann::json item;
+        item["path"] = b.path;
+        item["language"] = b.language;
+        item["mode"] = b.mode;
+        item["cursorLine"] = b.cursorLine;
+        item["cursorCol"] = b.cursorCol;
+        item["foldedLines"] = b.foldedLines;
+        j["buffers"].push_back(std::move(item));
+    }
+    return j;
+}
+
+inline SessionData sessionFromJson(const nlohmann::json& j) {
+    SessionData session;
+    session.workspaceRoot = j.value("workspaceRoot", "");
+    session.activePath = j.value("activePath", "");
+    session.layoutPreset = j.value("layoutPreset", "VSCode");
+    session.imguiIni = j.value("imguiIni", "");
+    if (j.contains("buffers") && j["buffers"].is_array()) {
+        for (const auto& item : j["buffers"]) {
+            SessionBufferState b;
+            b.path = item.value("path", "");
+            b.language = item.value("language", "");
+            b.mode = item.value("mode", "structured");
+            b.cursorLine = item.value("cursorLine", 1);
+            b.cursorCol = item.value("cursorCol", 1);
+            if (item.contains("foldedLines") && item["foldedLines"].is_array()) {
+                for (const auto& ln : item["foldedLines"]) {
+                    if (ln.is_number_integer()) b.foldedLines.push_back(ln.get<int>());
+                }
+            }
+            if (!b.path.empty()) session.buffers.push_back(std::move(b));
+        }
+    }
+    return session;
+}