FT: signature hint close and toggle functions (#242)

* signature hint close and toggle functions

* locally scope temporary vars

lua/scnvim/signature.lua

@@ -8,6 +8,7 @@ local sclang = require 'scnvim.sclang'
 local config = require 'scnvim.config'
 local api = vim.api
 local lsp_util = vim.lsp.util
+local hint_winid = nil
 
 local M = {}
 
@@ -101,7 +102,8 @@ local function show_signature(object)
       local signature = res:match '%((.+)%)'
       if signature then
         if float then
-          lsp_util.open_floating_preview({ signature }, 'supercollider', float_conf)
+          local _, id = lsp_util.open_floating_preview({ signature }, 'supercollider', float_conf)
+          hint_winid = id
         else
           print(signature)
         end
@@ -110,6 +112,11 @@ local function show_signature(object)
   end
 end
 
+local function close_signature()
+  vim.api.nvim_win_close(hint_winid, false)
+  hint_winid = nil
+end
+
 --- Show signature from normal mode
 function M.show()
   local ok, object = pcall(extract_object)
@@ -128,4 +135,20 @@ function M.ins_show()
   end
 end
 
+-- Close signature hint window
+function M.close()
+  if hint_winid ~= nil and vim.api.nvim_win_is_valid(hint_winid) then
+    pcall(close_signature)
+  end
+end
+
+-- Toggle signature hint window
+function M.toggle()
+  if hint_winid ~= nil and vim.api.nvim_win_is_valid(hint_winid) then
+    pcall(close_signature)
+  else
+    M.show()
+  end
+end
+
 return M