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

@@ -5,39 +5,64 @@ 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)
-fi
-
-# set normal command first
-if [ -z "$cmd" ]; then
-    if exist ptipython; then
-        cmd=ptipython
-    elif exist ipython; then
-        cmd=ipython
-    elif exist python; then
-        cmd=python
-    else
-        echo "No python found on system, please install." 1>&2
-        exit 1
-    fi
+	cmd_explicit=$(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
-    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
+	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
+    "$cmd_explicit"
+    exit 0
+fi
+
+# set normal command first
+if [ -z "$cmd" ]; then
+	if exist ptipython; then
+		cmd=ptipython
+	elif exist ipython; then
+		cmd=ipython
+	elif exist python; then
+		cmd=python
+	else
+		echo "No python found on system, please install." 1>&2
+		exit 1
+	fi
 fi
 
 # attach to kernel
 if [ -n "${session}" ]; then
-    if exist euporie-console || [ "$cmd" == "euporie-console" ]; then
-        euporie-console --edit-mode vi --connection-file "$session"
-    elif exist jupyter-console || [ "$cmd" == "jupyter-console" ]; then
-        jupyter-console --existing "$session"
-    fi
-# or just run normal python
-else
-    $cmd
+	if exist euporie-console; then
+		euporie-console --edit-mode vi --connection-file "$session"
+		exit 0
+	elif exist jupyter-console; then
+		jupyter-console --existing "$session"
+		exit 0
+	fi
 fi
+# or just run normal python
+$cmd