feat: save and restore mainview state when switching projects

src/project_manager.zig

@@ -58,17 +58,35 @@ pub fn shutdown() void {
     pid.send(.{"shutdown"}) catch {};
 }
 
-pub fn open(rel_project_directory: []const u8) (ProjectManagerError || FileSystemError || std.fs.File.OpenError || SetCwdError)!void {
+pub fn open(rel_project_directory: []const u8) (ProjectManagerError || FileSystemError || std.fs.File.OpenError || SetCwdError)!?[]const u8 {
     var path_buf: [std.fs.max_path_bytes]u8 = undefined;
     const project_directory = std.fs.cwd().realpath(rel_project_directory, &path_buf) catch "(none)";
     const current_project = tp.env.get().str("project");
-    if (std.mem.eql(u8, current_project, project_directory)) return;
+    if (std.mem.eql(u8, current_project, project_directory)) return get_project_state(project_directory);
     if (!root.is_directory(project_directory)) return error.InvalidProjectDirectory;
     var dir = try std.fs.openDirAbsolute(project_directory, .{});
     try dir.setAsCwd();
     dir.close();
     tp.env.get().str_set("project", project_directory);
-    return send(.{ "open", project_directory });
+    try send(.{ "open", project_directory });
+    return get_project_state(project_directory);
+}
+
+const project_state_allocator = std.heap.c_allocator;
+var project_state_mutex: std.Thread.Mutex = .{};
+var project_state: ProjectStateMap = .empty;
+const ProjectStateMap = std.StringHashMapUnmanaged([]const u8);
+
+fn get_project_state(project_directory: []const u8) ?[]const u8 {
+    project_state_mutex.lock();
+    defer project_state_mutex.unlock();
+    return project_state.get(project_directory);
+}
+
+pub fn store_state(project_directory: []const u8, state: []const u8) error{OutOfMemory}!void {
+    project_state_mutex.lock();
+    defer project_state_mutex.unlock();
+    try project_state.put(project_state_allocator, try project_state_allocator.dupe(u8, project_directory), state);
 }
 
 pub fn close(project_directory: []const u8) (ProjectManagerError || error{CloseCurrentProject})!void {

src/tui/mainview.zig

@@ -356,7 +356,8 @@ const cmds = struct {
     pub const quit_without_saving_meta: Meta = .{ .description = "Quit without saving" };
 
     pub fn open_project_cwd(self: *Self, _: Ctx) Result {
-        try project_manager.open(".");
+        if (try project_manager.open(".")) |state|
+            try self.restore_state(state);
         if (self.top_bar) |bar| _ = try bar.msg(.{ "PRJ", "open" });
         if (self.bottom_bar) |bar| _ = try bar.msg(.{ "PRJ", "open" });
     }
@@ -366,7 +367,8 @@ const cmds = struct {
         var project_dir: []const u8 = undefined;
         if (!try ctx.args.match(.{tp.extract(&project_dir)}))
             return;
-        try project_manager.open(project_dir);
+        if (try project_manager.open(project_dir)) |state|
+            try self.restore_state(state);
         const project = tp.env.get().str("project");
         tui.rdr().set_terminal_working_directory(project);
         if (self.top_bar) |bar| _ = try bar.msg(.{ "PRJ", "open" });
@@ -394,7 +396,18 @@ const cmds = struct {
         if (!try ctx.args.match(.{tp.extract(&project_dir)}))
             return;
         try self.check_all_not_dirty();
-        try project_manager.open(project_dir);
+
+        {
+            var state_writer: std.Io.Writer.Allocating = .init(self.allocator);
+            defer state_writer.deinit();
+            try self.write_state(&state_writer.writer);
+            try state_writer.writer.flush();
+            const old_project = tp.env.get().str("project");
+            try project_manager.store_state(old_project, try state_writer.toOwnedSlice());
+        }
+
+        const project_state = try project_manager.open(project_dir);
+
         try self.close_all_editors();
         self.delete_all_buffers();
         self.clear_find_in_files_results(.diagnostics);
@@ -402,10 +415,14 @@ const cmds = struct {
             try self.toggle_panel_view(filelist_view, false);
         self.buffer_manager.deinit();
         self.buffer_manager = Buffer.Manager.init(self.allocator);
+
         const project = tp.env.get().str("project");
         tui.rdr().set_terminal_working_directory(project);
+        if (project_state) |state| try self.restore_state(state);
+
         if (self.top_bar) |bar| _ = try bar.msg(.{ "PRJ", "open" });
         if (self.bottom_bar) |bar| _ = try bar.msg(.{ "PRJ", "open" });
+        if (project_state == null)
             tp.self_pid().send(.{ "cmd", "open_recent" }) catch return;
     }
     pub const change_project_meta: Meta = .{ .arguments = &.{.string} };
@@ -1657,6 +1674,11 @@ fn read_restore_info(self: *Self) !void {
     try self.extract_state(&iter);
 }
 
+fn restore_state(self: *Self, state: []const u8) !void {
+    var iter = state;
+    try self.extract_state(&iter);
+}
+
 fn extract_state(self: *Self, iter: *[]const u8) !void {
     tp.trace(tp.channel.debug, .{ "mainview", "extract" });
     var editor_file_path: ?[]const u8 = undefined;