cd to folder when doing nvim FOLDER and layout code

- when doing `nvim FOLDER` it works as expected, opening the tree
on the correct folder (updating the ROOT_PATH)
- add the code for keeping the tree window on the side no matter
what, but since the lack of window events, disable this feature.

lua/lib/winutils.lua

@@ -40,7 +40,7 @@ local BUF_OPTIONS = {
 }
 
 local WIN_WIDTH = 30
-local SIDE = 'topleft'
+local SIDE = 'H'
 
 if api.nvim_call_function('exists', { 'g:lua_tree_width' }) == 1 then
     WIN_WIDTH = api.nvim_get_var('lua_tree_width')
@@ -48,7 +48,7 @@ end
 
 if api.nvim_call_function('exists', { 'g:lua_tree_side' }) == 1 then
     if api.nvim_get_var('lua_tree_side') == 'right' then
-        SIDE = 'rightbelow'
+        SIDE = 'L'
     end
 end
 
@@ -66,13 +66,33 @@ local function open()
         api.nvim_buf_set_option(buf, opt, val)
     end
 
-    api.nvim_command(SIDE.. ' '..WIN_WIDTH..'vnew')
+    api.nvim_command('vnew')
+    api.nvim_command('wincmd '..SIDE)
+    api.nvim_command('vertical resize '..WIN_WIDTH)
     api.nvim_win_set_buf(0, buf)
     for _, opt in pairs(BUF_OPTIONS) do
         api.nvim_command('setlocal '..opt)
     end
 end
 
+local function replace_tree()
+    local win = get_win()
+    if not win then return end
+
+    local tree_position = api.nvim_win_get_position(win)
+    local win_width = api.nvim_win_get_width(win)
+    -- TODO: change this to check on right side with window width - win_width == tree_position[2]
+    if win_width == WIN_WIDTH and tree_position[2] == 0 then return end
+
+    local current_win = api.nvim_get_current_win()
+
+    api.nvim_set_current_win(win)
+    api.nvim_command('wincmd '..SIDE)
+    api.nvim_command('vertical resize '..WIN_WIDTH)
+
+    api.nvim_set_current_win(current_win)
+end
+
 local function close()
     local win = get_win()
     if not win then return end
@@ -97,11 +117,6 @@ local function update_view(update_cursor)
     end
 end
 
-
-local function is_win_open()
-    return get_buf() ~= nil
-end
-
 local function set_mappings()
     local buf = get_buf()
     if not buf then return end
@@ -125,6 +140,10 @@ local function set_mappings()
     end
 end
 
+local function is_win_open()
+    return get_buf() ~= nil
+end
+
 return {
     open = open;
     close = close;
@@ -133,4 +152,5 @@ return {
     get_buf = get_buf;
     get_win = get_win;
     set_mappings = set_mappings;
+    replace_tree = replace_tree;
 }

lua/tree.lua

@@ -23,6 +23,7 @@ local is_win_open = winutils.is_win_open
 local close = winutils.close
 local open = winutils.open
 local set_mappings = winutils.set_mappings
+local replace_tree = winutils.replace_tree
 
 local git = require 'lib/git'
 local refresh_git = git.refresh_git
@@ -50,11 +51,9 @@ local function open_file(open_type)
     if node.name == '..' then
         api.nvim_command('cd ..')
 
-        local new_path
-        if get_cwd() == '/' then
-            new_path = '/'
-        else
-            new_path = get_cwd() .. '/'
+        local new_path = get_cwd()
+        if new_path ~= '/' then
+            new_path = new_path .. '/'
         end
 
         set_root_path(new_path)
@@ -132,7 +131,20 @@ end
 
 local function check_buffer_and_open()
     local bufname = api.nvim_buf_get_name(0)
-    if bufname == '' or is_dir(bufname) then toggle() end
+    if bufname == '' then
+        toggle()
+    elseif is_dir(bufname) then
+        api.nvim_command('cd ' .. bufname)
+
+        local new_path = get_cwd()
+        if new_path ~= '/' then
+            new_path = new_path .. '/'
+        end
+        set_root_path(new_path)
+        init_tree()
+
+        toggle()
+    end
 end
 
 return {
@@ -142,5 +154,6 @@ return {
     refresh = refresh;
     check_windows_and_close = check_windows_and_close;
     check_buffer_and_open = check_buffer_and_open;
+    replace_tree = replace_tree;
 }