Add Connections to SSG_LIB, reusing the TRO mechanisms

A connection is a CONNECTION_ARROW block sitting at the midpoint of an arrow
between two TRO markers. It stores the relationship as attributes rather than by
position:

    TRO11  ---------->  TRO14
    UID 0062            UID 0065

Same architecture as the TRO feature, nothing new introduced:

  Blockname CONNECTION_*  ->  c:CONNECTION_EDIT (Lisp/Connection_Edit.lsp)
                          ->  dcl/connection_edit.dcl

The double-click and EATTEDIT hooks already route every INSERT through
SSG_BLOCKEDIT, so this is one more branch in that dispatcher - placed before the
TRO branch since both come from the same annotation run and the patterns must not
overlap. DCL path from DXFM_DCL, ssg-start/ssg-end, ssg-attrib-read and
ssg-attrib-set-on, all text via ssg-text/ssg-textf with 16 new keys in both
language files. Loading is lazy: not preloaded in the MNL, pulled by the menu
macros and the dispatcher with (ssg-ensure "Connection_Edit"), with a fallback to
native EATTEDIT if the module is missing.

CONNECTION_INSERT picks two TRO markers and draws the connection; the new
internal number comes from ssg-id-max/ssg-id-format, so it stays inside the
SSG_LIB number space. It refuses when the block definition is absent - the shape
comes from tro_annotate.py, this command does not invent one.

Menu: SSG_LIB > Connections with Verbindung einfuegen, Verbindung bearbeiten and
Bearbeiten (Auto), plus an entry in the POP501 edit context menu.

On the internal id: the markers keep their visible ID (TRO11) untouched - the
existing TRO_INSERT/tro-naechste-id read it and the request was explicit about
not changing it. The permanent unique number therefore lives in a separate
attribute UID, in the same four-digit space as ssg_id and the CSV TeileId.
Putting it into ID was tried and reverted: IDSCHECK treats ID as numeric and
would have overwritten TRO11 with a number while correcting duplicates.
Connections reference the UIDs, so the relationship survives a renamed or moved
marker.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

Lisp/Connection_Edit.lsp

@@ -0,0 +1,254 @@
+;; ============================================================
+;; CONNECTION_EDIT.LSP - Verbindungen zwischen TROs
+;;
+;; Eine Verbindung ist ein Block CONNECTION_ARROW in der Mitte eines Pfeils
+;; zwischen zwei TRO-Markern. Sie haelt die Beziehung ueber die *internen* IDs
+;; der beiden TROs fest, nicht ueber die Lage im Plan:
+;;
+;;     TRO11  ---------->  TRO14
+;;     ID 0062             ID 0065
+;;
+;; Attribute des Verbindungsblocks:
+;;   ID        unsichtbar - eindeutige interne Nummer (ID-Raum von SSG_LIB)
+;;   FROM_ID   unsichtbar - interne ID der Quelle
+;;   TO_ID     unsichtbar - interne ID des Ziels
+;;   FROM_TRO  sichtbar   - sprechender Name der Quelle
+;;   TO_TRO    sichtbar   - sprechender Name des Ziels
+;;   KIND      unsichtbar - flow | colocated
+;;
+;; Warum interne IDs: der sprechende Name darf sich aendern (TRO_EDIT), die
+;; interne ID nicht. Ein DXF-Export kann die Beziehung damit eindeutig
+;; rekonstruieren, auch wenn Marker verschoben oder umbenannt wurden.
+;;
+;; Befehle:
+;;   CONNECTION_INSERT - zwei TRO-Marker waehlen, Verbindung einzeichnen
+;;   CONNECTION_EDIT   - Quelle/Ziel einer bestehenden Verbindung aendern
+;;
+;; Aufruf:
+;;   - Doppelklick auf die Verbindung -> ***DOUBLECLICK [INSERT] -> SSG_BLOCKEDIT
+;;   - EATTEDIT                       -> c:EATTEDIT -> SSG_BLOCKEDIT
+;;   - Menue SSG_LIB > Connections
+;;   Der Dispatcher SSG_BLOCKEDIT leitet Blocknamen "CONNECTION_*" hierher.
+;;
+;; Setzt ssg_core.lsp (ssg-start/ssg-end, ssg-attrib-*), ssg_lang.lsp und
+;; ssg_id.lsp (ssg-id-max, ssg-id-format) voraus.
+;; ============================================================
+
+(setq *connection-block* "CONNECTION_ARROW")
+
+
+;; ------------------------------------------------------------
+;; Attribut eines Blocks lesen ("" wenn nicht vorhanden)
+;; ------------------------------------------------------------
+(defun con-attrib (ent tag / wert)
+  (setq wert (cdr (assoc tag (ssg-attrib-read ent))))
+  (if wert wert "")
+)
+
+
+;; ------------------------------------------------------------
+;; Einen TRO-Marker waehlen; liefert (ename interne-ID sprechender-Name)
+;; oder nil bei Abbruch bzw. falschem Block.
+;; ------------------------------------------------------------
+(defun con-pick-tro (prompt-key / sel ent bname)
+  (setq sel (entsel (ssg-text prompt-key)))
+  (if (null sel)
+    nil
+    (progn
+      (setq ent   (car sel)
+            bname (cdr (assoc 2 (entget ent))))
+      (if (not (wcmatch bname "TRO_*"))
+        (progn (alert (ssg-textf "con-kein-tro" (list bname))) nil)
+        (list ent (con-attrib ent "ID") (con-attrib ent "TRO_ID"))
+      )
+    )
+  )
+)
+
+
+;; ------------------------------------------------------------
+;; C:CONNECTION_INSERT - Verbindung zwischen zwei TRO-Markern einzeichnen
+;;
+;; Zeichnet Schaft und Spitze auf den Fluss-Layer und setzt den
+;; Verbindungsblock in die Mitte, ausgerichtet entlang des Pfeils.
+;; ------------------------------------------------------------
+(defun c:CONNECTION_INSERT ( / von nach p1 p2 dx dy laenge winkel mitte
+                              kopf ent-neu neue-id layer-name)
+  (ssg-start "CONNECTION_INSERT" '(("OSMODE") ("ATTREQ") ("ATTDIA") ("CLAYER")))
+  (setvar "OSMODE" 0)
+
+  (if (not (tblsearch "BLOCK" *connection-block*))
+    (progn
+      (alert (ssg-textf "con-block-fehlt" (list *connection-block*)))
+      (ssg-end)
+      (exit)
+    )
+  )
+
+  (setq von (con-pick-tro "con-quelle-waehlen"))
+  (if (null von) (progn (ssg-end) (exit)))
+  (setq nach (con-pick-tro "con-ziel-waehlen"))
+  (if (null nach) (progn (ssg-end) (exit)))
+
+  (if (= (car von) (car nach))
+    (progn (alert (ssg-text "con-gleicher-block")) (ssg-end) (exit))
+  )
+
+  (setq p1 (cdr (assoc 10 (entget (car von))))
+        p2 (cdr (assoc 10 (entget (car nach)))))
+  (setq dx     (- (car p2) (car p1))
+        dy     (- (cadr p2) (cadr p1))
+        laenge (distance p1 p2))
+  (if (<= laenge 1e-6)
+    (progn (alert (ssg-text "con-gleicher-punkt")) (ssg-end) (exit))
+  )
+  (setq winkel (atan dy dx)
+        mitte  (list (/ (+ (car p1) (car p2)) 2.0)
+                     (/ (+ (cadr p1) (cadr p2)) 2.0)
+                     0.0))
+
+  ;; Layer wie die uebrigen Verbindungen der Beschriftung
+  (setq layer-name "TRO_FLOW")
+  (ssg-make-layer layer-name "5" T)
+
+  ;; Schaft
+  (entmake (list (cons 0 "LWPOLYLINE")
+                 (cons 100 "AcDbEntity")
+                 (cons 8 layer-name)
+                 (cons 100 "AcDbPolyline")
+                 (cons 90 2)
+                 (cons 70 0)
+                 (cons 10 (list (car p1) (cadr p1)))
+                 (cons 10 (list (car p2) (cadr p2)))))
+
+  ;; Verbindungsblock in die Mitte, entlang des Pfeils gedreht
+  (setvar "ATTREQ" 0)
+  (setvar "ATTDIA" 0)
+  (command "_.-INSERT" *connection-block* mitte "" "" (angtos winkel 0 8))
+  (setq ent-neu (entlast))
+
+  ;; Eindeutige interne ID im ID-Raum von SSG_LIB
+  (setq neue-id (ssg-id-format (1+ (ssg-id-max))))
+  (ssg-attrib-set-on ent-neu
+    (list (cons "ID"       neue-id)
+          (cons "FROM_ID"  (cadr von))
+          (cons "TO_ID"    (cadr nach))
+          (cons "FROM_TRO" (caddr von))
+          (cons "TO_TRO"   (caddr nach))
+          (cons "KIND"     "flow")))
+  (entupd ent-neu)
+
+  (princ (ssg-textf "con-eingefuegt"
+           (list (caddr von) (caddr nach) neue-id)))
+  (ssg-end)
+  (princ)
+)
+
+
+;; ------------------------------------------------------------
+;; C:CONNECTION_EDIT - Quelle/Ziel einer Verbindung aendern
+;; ------------------------------------------------------------
+(defun c:CONNECTION_EDIT ( / ss ent ed bname
+                            alt-from-id alt-to-id alt-from alt-to alt-kind
+                            neu-from-id neu-to-id neu-from neu-to
+                            dcl-pfad dat ergebnis)
+
+  ;; Implied Selection VOR ssg-start pruefen (ssg-start hebt Selektion auf)
+  (setq ss (ssget "I"))
+  (if (and ss (= (sslength ss) 1)
+           (= (cdr (assoc 0 (entget (ssname ss 0)))) "INSERT"))
+    (setq ent (ssname ss 0))
+  )
+
+  (ssg-start "CONNECTION_EDIT" nil)
+
+  (if (null ent)
+    (progn
+      (princ (ssg-text "cmd-block-auswaehlen"))
+      (setq ss (ssget ":S" '((0 . "INSERT"))))
+      (if ss (setq ent (ssname ss 0)))
+    )
+  )
+  (if (null ent)
+    (progn (princ (ssg-text "cmd-kein-block-ausgewaehlt")) (ssg-end) (exit))
+  )
+
+  (setq ed    (entget ent)
+        bname (cdr (assoc 2 ed)))
+  (if (not (wcmatch bname "CONNECTION_*"))
+    (progn
+      (alert (ssg-textf "con-keine-verbindung" (list bname)))
+      (ssg-end)
+      (exit)
+    )
+  )
+
+  (setq alt-from-id (con-attrib ent "FROM_ID")
+        alt-to-id   (con-attrib ent "TO_ID")
+        alt-from    (con-attrib ent "FROM_TRO")
+        alt-to      (con-attrib ent "TO_TRO")
+        alt-kind    (con-attrib ent "KIND"))
+
+  (setq dcl-pfad (strcat (getenv "DXFM_DCL") "/connection_edit.dcl"))
+  (setq dat (load_dialog dcl-pfad))
+  (if (not (new_dialog "connection_edit" dat))
+    (progn
+      (alert (ssg-textf "con-dialog-fehlt" (list dcl-pfad)))
+      (ssg-end)
+      (exit)
+    )
+  )
+
+  (set_tile "blockname" (ssg-textf "con-block" (list bname (con-attrib ent "ID"))))
+  (set_tile "from_id"  alt-from-id)
+  (set_tile "from_tro" alt-from)
+  (set_tile "to_id"    alt-to-id)
+  (set_tile "to_tro"   alt-to)
+  (set_tile "richtung" (ssg-textf "con-richtung" (list alt-from alt-to)))
+  (set_tile "hinweis"  (ssg-text "con-hinweis"))
+
+  (setq neu-from-id alt-from-id neu-to-id alt-to-id
+        neu-from    alt-from    neu-to    alt-to)
+
+  (action_tile "from_id"  "(setq neu-from-id (get_tile \"from_id\"))")
+  (action_tile "to_id"    "(setq neu-to-id (get_tile \"to_id\"))")
+  (action_tile "from_tro" "(setq neu-from (get_tile \"from_tro\"))")
+  (action_tile "to_tro"   "(setq neu-to (get_tile \"to_tro\"))")
+  (action_tile "accept"
+    (strcat "(setq neu-from-id (get_tile \"from_id\")"
+            "      neu-to-id   (get_tile \"to_id\")"
+            "      neu-from    (get_tile \"from_tro\")"
+            "      neu-to      (get_tile \"to_tro\"))"
+            "(done_dialog 1)"))
+  (action_tile "cancel" "(done_dialog 0)")
+
+  (setq ergebnis (start_dialog))
+  (unload_dialog dat)
+
+  (if (= ergebnis 1)
+    (if (or (= (vl-string-trim " " neu-from-id) "")
+            (= (vl-string-trim " " neu-to-id) ""))
+      (alert (ssg-text "con-id-leer"))
+      (if (= neu-from-id neu-to-id)
+        (alert (ssg-text "con-gleiche-id"))
+        (progn
+          (ssg-attrib-set-on ent
+            (list (cons "FROM_ID"  neu-from-id)
+                  (cons "TO_ID"    neu-to-id)
+                  (cons "FROM_TRO" neu-from)
+                  (cons "TO_TRO"   neu-to)
+                  (cons "KIND"     (if (= alt-kind "") "flow" alt-kind))))
+          (entupd ent)
+          (princ (ssg-textf "con-gespeichert" (list neu-from neu-to)))
+        )
+      )
+    )
+  )
+
+  (ssg-end)
+  (princ)
+)
+
+
+(prompt "\nConnection_Edit.lsp geladen - Befehle: CONNECTION_INSERT, CONNECTION_EDIT")
+(princ)

Lisp/SSG_LIB_Commands.lsp

@@ -439,6 +439,23 @@
       (c:VARIOFOERDERER_EDIT)
     )
 
+    ;; Verbindungen (CONNECTION_*) -> CONNECTION_EDIT (DCL-Dialog)
+    ;; Vor der TRO-Pruefung, da beide aus der Beschriftung von sps_skel stammen
+    ;; und sich die Namensmuster nicht ueberschneiden duerfen.
+    ((wcmatch bname "CONNECTION_*")
+      (princ (ssg-textf "cmd-connection-bearbeiten" (list bname)))
+      (if (and (null *ssg-Connection_Edit-loaded*) (atoms-family 1 '("SSG-ENSURE")))
+        (ssg-ensure "Connection_Edit")
+      )
+      (if (atoms-family 1 '("C:CONNECTION_EDIT"))
+        (c:CONNECTION_EDIT)
+        (progn
+          (princ (ssg-textf "tro-edit-modul-fehlt" (list "Connection_Edit.lsp")))
+          (command "_.EATTEDIT")
+        )
+      )
+    )
+
     ;; TRO-Marker (TRO_SYM_<Typ>) -> TRO_EDIT (DCL-Dialog)
     ;; Die Marker kommen aus sps_skel (lib/tro_annotate.py) und tragen die
     ;; Attribute ID und TYPE. Modul bei Bedarf nachladen, damit der Doppelklick

Lisp/Tro_Edit.lsp

@@ -245,7 +245,7 @@
 ;; C:TRO_EDIT - Dialog fuer einen TRO-Marker
 ;; ------------------------------------------------------------
 (defun c:TRO_EDIT ( / ss ent ed bname attribs
-                      alt-id alt-type alt-fb
+                      alt-id alt-type alt-fb int-id
                       neu-id neu-type
                       liste idx dcl-pfad dat ergebnis)
 
@@ -284,7 +284,8 @@
   (setq attribs  (ssg-attrib-read ent)
         alt-id   (cdr (assoc "ID" attribs))
         alt-type (cdr (assoc "TYPE" attribs))
-        alt-fb   (cdr (assoc "FB_BLOCK" attribs)))
+        alt-fb   (cdr (assoc "FB_BLOCK" attribs))
+        int-id   (cdr (assoc "UID" attribs)))
 
   (if (null alt-id)
     (progn
@@ -310,7 +311,8 @@
         idx   (tro-index alt-type liste))
 
   (set_tile "blockname" (ssg-textf "tro-edit-block" (list bname)))
-  (set_tile "fb" (ssg-textf "tro-edit-fb" (list (if alt-fb alt-fb "-"))))
+  (set_tile "fb" (ssg-textf "tro-edit-fb"
+                   (list (if alt-fb alt-fb "-") (if int-id int-id "-"))))
   (set_tile "hinweis" (ssg-text "tro-edit-hinweis"))
   (set_tile "id" alt-id)
   (start_list "type")

Lisp/ssg_load.lsp

@@ -35,6 +35,7 @@
   (load (strcat base-path "tests.lsp")            "tests.lsp nicht gefunden")
   (load (strcat base-path "OmniModulInsert.lsp")  "OmniModulInsert.lsp nicht gefunden")
   (load (strcat base-path "Tro_Edit.lsp")         "Tro_Edit.lsp nicht gefunden")
+  (load (strcat base-path "Connection_Edit.lsp")  "Connection_Edit.lsp nicht gefunden")
   (load (strcat base-path "SSG_LIB_Commands.lsp")  "SSG_LIB_Commands.lsp nicht gefunden")
   (prompt "\nSSG-Bibliotheken geladen: ssg_core, ssg_lang, ssg_dbg, ssg_dialog, ssg_layer, KreiselInsert, VarioFoerderer, Gefaellestrecke, export, tests, OmniModulInsert, SSG_LIB_Commands")
   (princ)

dcl/connection_edit.dcl

@@ -0,0 +1,59 @@
+// ============================================================
+// connection_edit.dcl - Verbindung zwischen zwei TROs bearbeiten
+// Aendert Quelle und Ziel eines CONNECTION_*-Blocks. Gearbeitet wird
+// mit den internen IDs; die sprechenden Namen stehen daneben.
+// Aufruf ueber c:CONNECTION_EDIT (Lisp/Connection_Edit.lsp).
+// ============================================================
+
+connection_edit : dialog {
+  label = "Verbindung bearbeiten";
+
+  : column {
+
+    : text {
+      key = "blockname";
+      label = "";
+    }
+
+    : boxed_column {
+      label = "Quelle";
+      : edit_box {
+        key = "from_id";
+        label = "Interne ID:";
+        edit_width = 12;
+      }
+      : edit_box {
+        key = "from_tro";
+        label = "TRO-Kennung:";
+        edit_width = 24;
+      }
+    }
+
+    : boxed_column {
+      label = "Ziel";
+      : edit_box {
+        key = "to_id";
+        label = "Interne ID:";
+        edit_width = 12;
+      }
+      : edit_box {
+        key = "to_tro";
+        label = "TRO-Kennung:";
+        edit_width = 24;
+      }
+    }
+
+    : text {
+      key = "richtung";
+      label = "";
+    }
+
+    : text {
+      key = "hinweis";
+      label = "";
+    }
+
+  }
+
+  ok_cancel;
+}

menu/SSG_LIB.mnu

@@ -130,6 +130,10 @@
 [Marker einfuegen]^C^C(ssg-ensure "Tro_Edit") TRO_INSERT
 [Marker bearbeiten]^C^C(ssg-ensure "Tro_Edit") TRO_EDIT
 [<-Bearbeiten (Auto)]^C^C(ssg-ensure "SSG_LIB_Commands") SSG_BLOCKEDIT
+[->Connections]
+[Verbindung einfuegen]^C^C(ssg-ensure "Connection_Edit") CONNECTION_INSERT
+[Verbindung bearbeiten]^C^C(ssg-ensure "Connection_Edit") CONNECTION_EDIT
+[<-Bearbeiten (Auto)]^C^C(ssg-ensure "SSG_LIB_Commands") SSG_BLOCKEDIT
 [->Export]
 [Export Sivas]^C^C(ssg-ensure "count_sep_scan") ZAEHLE_SEP_SCAN (ssg-ensure "export") EXPORTSIVAS
 [<-Export CSV]^C^C(ssg-ensure "export") EXPORTCSV
@@ -167,5 +171,6 @@
 [Gefaellestrecke bearbeiten](ssg-ensure "Gefaellestrecke") GEFAELLESTRECKE_EDIT
 [VarioFoerderer bearbeiten](ssg-ensure "VarioFoerderer") VARIOFOERDERER_EDIT
 [TRO-Marker bearbeiten](ssg-ensure "Tro_Edit") TRO_EDIT
+[Verbindung bearbeiten](ssg-ensure "Connection_Edit") CONNECTION_EDIT
 [--]
 [SSG Bearbeiten (Auto)](ssg-ensure "SSG_LIB_Commands") SSG_BLOCKEDIT