Setup the RpcServer path in Settings and environment

* Handle DELTACHAR_RPC_SERVER environment
* Save the path in settings to avoid startup scans
* Advanced section in settings to customize it

Author: radare

src/account_finder.vala

@@ -11,8 +11,17 @@ namespace Dc {
 
         /**
          * Return an absolute path to deltachat-rpc-server, or null if none found.
+         *
+         * When `override_path` is non-empty, it is used exclusively: if it is
+         * not executable, null is returned so the caller can surface a
+         * "configured path is broken" error instead of silently falling back
+         * to the scan.
          */
-        public static string? find_rpc_server () {
+        public static string? find_rpc_server (string? override_path = null) {
+            if (override_path != null && override_path.length > 0) {
+                return FileUtils.test (override_path, FileTest.IS_EXECUTABLE) ? override_path : null;
+            }
+
             /* PATH first — covers distro packages, /usr/local, and ~/.local/bin
              * when the user has it exported. */
             string? in_path = Environment.find_program_in_path (RPC_BIN);

src/settings_dialog.vala

@@ -8,6 +8,7 @@ namespace Dc {
         public bool markdown_rendering { get; set; default = false; }
         public bool shift_enter_sends { get; set; default = false; }
         public bool notifications_enabled { get; set; default = true; }
+        public string rpc_server_path { get; set; default = ""; }
 
         public static string get_config_path () {
             return Path.build_filename (
@@ -24,6 +25,7 @@ namespace Dc {
             Markdown.enabled = markdown_rendering;
             shift_enter_sends = kf_bool (kf, "shift_enter_sends", false);
             notifications_enabled = kf_bool (kf, "notifications_enabled", true);
+            rpc_server_path = kf_str (kf, "rpc_server_path", "");
         }
 
         private static int kf_int (KeyFile kf, string k, int d) {
@@ -34,6 +36,10 @@ namespace Dc {
             try { return kf.get_boolean ("General", k); } catch { return d; }
         }
 
+        private static string kf_str (KeyFile kf, string k, string d) {
+            try { return kf.get_string ("General", k); } catch { return d; }
+        }
+
         public void save_double_click_action (int v) {
             double_click_action = v;
             save_to_file ((kf) => { kf.set_integer ("General", "double_click_action", v); });
@@ -54,6 +60,11 @@ namespace Dc {
             save_to_file ((kf) => { kf.set_boolean ("General", "notifications_enabled", v); });
         }
 
+        public void save_rpc_server_path (string v) {
+            rpc_server_path = v;
+            save_to_file ((kf) => { kf.set_string ("General", "rpc_server_path", v); });
+        }
+
         public void save_to_file (SettingWriter writer) {
             var kf = new KeyFile ();
             try {
@@ -76,6 +87,8 @@ namespace Dc {
         private Gtk.ListBox accounts_list;
         private Gtk.Box content;
         private unowned Window app_window;
+        private Adw.ActionRow rpc_row;
+        private Gtk.Switch rpc_custom_switch;
 
         public signal void account_changed ();
 
@@ -196,6 +209,39 @@ namespace Dc {
             behavior_list.append (notif_row);
             content.append (behavior_list);
 
+            /* Advanced section */
+            var advanced_label = new Gtk.Label ("Advanced");
+            advanced_label.add_css_class ("title-3");
+            advanced_label.halign = Gtk.Align.START;
+            content.append (advanced_label);
+
+            var advanced_list = new Gtk.ListBox ();
+            advanced_list.selection_mode = Gtk.SelectionMode.NONE;
+            advanced_list.add_css_class ("boxed-list");
+
+            rpc_row = new Adw.ActionRow ();
+            rpc_row.title = "deltachat-rpc-server";
+
+            var rpc_choose_btn = new Gtk.Button.with_label ("Choose…");
+            rpc_choose_btn.valign = Gtk.Align.CENTER;
+            rpc_choose_btn.add_css_class ("flat");
+            rpc_choose_btn.tooltip_text = "Pick a deltachat-rpc-server binary";
+            rpc_choose_btn.clicked.connect (() => { on_browse_rpc_server.begin (); });
+            rpc_row.add_suffix (rpc_choose_btn);
+
+            rpc_custom_switch = new Gtk.Switch ();
+            rpc_custom_switch.valign = Gtk.Align.CENTER;
+            rpc_custom_switch.tooltip_text = "Use a custom deltachat-rpc-server binary";
+            rpc_custom_switch.active = app_window.settings.rpc_server_path.length > 0;
+            rpc_custom_switch.notify["active"].connect (on_rpc_switch_toggled);
+            rpc_custom_switch.bind_property ("active", rpc_choose_btn, "sensitive",
+                                             BindingFlags.SYNC_CREATE);
+            rpc_row.add_suffix (rpc_custom_switch);
+
+            advanced_list.append (rpc_row);
+            content.append (advanced_list);
+            update_rpc_row ();
+
             var scroll = new Gtk.ScrolledWindow ();
             scroll.vexpand = true;
             scroll.hscrollbar_policy = Gtk.PolicyType.NEVER;
@@ -373,6 +419,58 @@ namespace Dc {
                 "remove", "Remove", () => { do_remove_account.begin (acct_id); });
         }
 
+        private void update_rpc_row () {
+            string custom = app_window.settings.rpc_server_path;
+            if (custom.length > 0) {
+                bool ok = FileUtils.test (custom, FileTest.IS_EXECUTABLE);
+                rpc_row.subtitle = ok ? "Custom" : "❌ Custom path is not executable";
+                rpc_row.tooltip_text = custom;
+            } else {
+                string? found = AccountFinder.find_rpc_server ();
+                rpc_row.subtitle = found != null ? "Auto-detected" : "❌ Not found";
+                rpc_row.tooltip_text = found ?? "No deltachat-rpc-server binary in the default locations";
+            }
+        }
+
+        private void on_rpc_switch_toggled () {
+            if (rpc_custom_switch.active) {
+                on_browse_rpc_server.begin ();
+            } else if (app_window.settings.rpc_server_path.length > 0) {
+                app_window.settings.save_rpc_server_path ("");
+                app_window.show_toast ("Using auto-detected RPC server. Restart to apply.");
+                update_rpc_row ();
+            }
+        }
+
+        private async void on_browse_rpc_server () {
+            var dlg = new Gtk.FileDialog ();
+            dlg.title = "Locate deltachat-rpc-server";
+            dlg.modal = true;
+
+            string start = app_window.settings.rpc_server_path;
+            if (start.length == 0) start = AccountFinder.find_rpc_server () ?? "";
+            if (start.length > 0) dlg.initial_file = File.new_for_path (start);
+
+            try {
+                var file = yield dlg.open (app_window, null);
+                if (file != null) {
+                    string? path = file.get_path ();
+                    if (path != null && FileUtils.test (path, FileTest.IS_EXECUTABLE)) {
+                        app_window.settings.save_rpc_server_path (path);
+                        app_window.show_toast ("RPC server path saved. Restart to apply.");
+                    } else {
+                        show_error (app_window, "Selected file is not an executable binary.");
+                    }
+                }
+            } catch (Error e) {
+                if (!(e is Gtk.DialogError) && !(e is IOError.CANCELLED))
+                    show_error (app_window, e.message);
+            }
+            /* Sync switch to actual state — reverts the toggle if nothing was saved. */
+            rpc_custom_switch.active = app_window.settings.rpc_server_path.length > 0;
+            update_rpc_row ();
+        }
+
         private async void do_remove_account (int acct_id) {
             try {
                 yield rpc.remove_account (acct_id);

src/window.vala

@@ -211,11 +211,16 @@ namespace Dc {
         private async void try_connect () {
             rpc = ((Dc.Application) this.application).rpc;
 
-            /* Find the RPC server binary */
-            string? rpc_path = AccountFinder.find_rpc_server ();
+            /* Reset any error widget left from a previous failed attempt. */
+            empty_status.child = null;
+            empty_status.icon_name = "mail-send-receive-symbolic";
+            empty_status.title = "Delta Chat";
+            empty_status.description = "Select a chat to start messaging,\nor wait for the connection…";
+
+            /* Find the RPC server binary — user override then auto-scan. */
+            string? rpc_path = AccountFinder.find_rpc_server (settings.rpc_server_path);
             if (rpc_path == null) {
-                show_toast ("Delta Chat RPC server not found. Install deltachat-rpc-server.");
-                empty_status.description = "deltachat-rpc-server not found.\nInstall it with: pip install deltachat-rpc-server";
+                show_rpc_not_found ();
                 return;
             }
 
@@ -271,6 +276,24 @@ namespace Dc {
             }
         }
 
+        private void show_rpc_not_found () {
+            empty_status.icon_name = "dialog-error-symbolic";
+            empty_status.title = "RPC server not found";
+            empty_status.description = settings.rpc_server_path.length > 0
+                ? "Configured path is missing or not executable:\n" + settings.rpc_server_path
+                : "deltachat-rpc-server was not found.\nOpen Settings to locate it, or install it.";
+
+            var btn = new Gtk.Button.with_label ("Open Settings…");
+            btn.add_css_class ("suggested-action");
+            btn.add_css_class ("pill");
+            btn.halign = Gtk.Align.CENTER;
+            btn.clicked.connect (show_settings_dialog);
+            empty_status.child = btn;
+
+            content_stack.visible_child_name = "empty";
+            show_toast ("Delta Chat RPC server not found");
+        }
+
         /* ================================================================
          *  Chat List
          * ================================================================ */
@@ -568,7 +591,12 @@ namespace Dc {
 
             var dialog = new SettingsDialog (rpc, this);
             active_modal = dialog;
-            dialog.closed.connect (() => { active_modal = null; });
+            dialog.closed.connect (() => {
+                active_modal = null;
+                if (!rpc.is_connected && settings.rpc_server_path.length > 0) {
+                    try_connect.begin ();
+                }
+            });
             dialog.account_changed.connect (() => {
                 reload_active_account.begin ();
             });