Add tm command to dynamically attach to tmux sessions

If a session is running, run a detached session. (Detach
all other clients.) If no session with the name is
running, create a new session and attach. Session name
can be passed in, or defaults to current directory name.

.config/zsh/scripts/tm

@@ -0,0 +1,43 @@
+#!/bin/sh
+#
+# Attach to a tmux session, or create it if it doesnt exist
+
+if [ -e $XDG_CONFIG_HOME/tmux/tmux.conf ]; then
+	start="tmux -f $XDG_CONFIG_HOME/tmux/tmux.conf"
+else
+	start=tmux
+fi
+
+path_name="$(basename "$PWD" | tr . -)"
+curr_dir=${1-$path_name}
+session_name=${1:-$curr_dir}
+
+_not_in_tmux() {
+  [ -z "$TMUX" ]
+}
+
+_session_exists() {
+  $start has-session -t "$session_name"
+}
+
+_create_detached_session() {
+  (TMUX='' $start new-session -Ad -s "$session_name")
+}
+
+_get_session_name() {
+  #${1:-$session_name}
+  return "blubb"
+}
+
+_attach_or_create() {
+  if _not_in_tmux; then
+    $start new-session -As "$session_name"
+  else
+    if ! _session_exists; then
+      _create_detached_session
+    fi
+    $start switch-client -t "$session_name"
+  fi
+}
+
+_attach_or_create