scripts: Refactor py script

Made detection and setup a little more stable, will still have its kinks since
it is rather hastily put together but should work for detecting kernels,
invoking the right python repl and letting you set it manually with `py -c`.

scripts/.local/bin/py

@@ -5,7 +5,39 @@ cur_dir=$(pwd)
 search_dir="${molten_session_dir}${cur_dir}"
 
 if [ "$1" == "-c" ]; then
-    cmd=$(echo -e "euporie-console\njupyter-console\nptipython\nipython\npython" | fzf)
+	cmd_explicit=$(echo -e "euporie-console\njupyter-console\nptipython\nipython\npython" | fzf)
+fi
+
+# search for molten session for current dir
+if [ -n "$(ls -A "${search_dir}" 2>/dev/null)" ]; then
+	session=$(find "$search_dir" -maxdepth 1 -type f -name "*.json")
+	if [ "$(echo "$session" | wc -l)" -gt 1 ]; then
+		session=$(echo "$session" | fzf --prompt "Molten session> ")
+	fi
+fi
+
+if [ -n "$cmd_explicit" ] && not exist "$cmd_explicit"; then
+    echo "Command $cmd_explicit not found."
+    exit 1
+elif [ "$cmd_explicit" == "euporie-console" ]; then
+	if [ -n "$session" ]; then
+		euporie-console --edit-mode vi --connection-file "$session"
+	else
+		echo "Starting euporie without a session to attach to."
+		euporie-console --edit-mode vi
+	fi
+    exit 0
+elif [ "$cmd_explicit" == "jupyter-console" ]; then
+	if [ -n "$session" ]; then
+		jupyter-console --existing "$session"
+	else
+		echo "Starting jupyter console without a session to attach to."
+		jupyter-console
+	fi
+    exit 0
+elif [ -n "$cmd_explicit" ]; then
+    "$cmd_explicit"
+    exit 0
 fi
 
 # set normal command first
@@ -22,22 +54,15 @@ if [ -z "$cmd" ]; then
 	fi
 fi
 
-# search for molten session for current dir
-if [ -n "$(ls -A "${search_dir}" 2>/dev/null)" ]; then
-    res=$(find "$search_dir" -maxdepth 1 -type f -name "*.json")
-    if [ "$(echo "$res" | wc -l)" -gt 1 ]; then
-        session=$(echo "$res" | fzf --prompt "Molten session> ")
-    fi
-fi
-
 # attach to kernel
 if [ -n "${session}" ]; then
-    if exist euporie-console || [ "$cmd" == "euporie-console" ]; then
+	if exist euporie-console; then
 		euporie-console --edit-mode vi --connection-file "$session"
-    elif exist jupyter-console || [ "$cmd" == "jupyter-console" ]; then
+		exit 0
+	elif exist jupyter-console; then
 		jupyter-console --existing "$session"
+		exit 0
 	fi
-# or just run normal python
-else
-    $cmd
 fi
+# or just run normal python
+$cmd