fix &background value detection

autoload/lightline/colorscheme.vim

@@ -2,7 +2,7 @@
 " Filename: autoload/lightline/colorscheme.vim
 " Author: itchyny
 " License: MIT License
-" Last Change: 2015/03/18 08:37:17.
+" Last Change: 2017/11/28 21:25:13.
 " =============================================================================
 
 let s:save_cpo = &cpo
@@ -224,5 +224,32 @@ function! lightline#colorscheme#flatten(p) abort
   return a:p
 endfunction
 
+if has('gui_running')
+  function! lightline#colorscheme#background() abort
+    return &background
+  endfunction
+else
+  " &background is set inappropriately when the colorscheme sets ctermbg of the Normal group
+  function! lightline#colorscheme#background() abort
+    let bg_color = synIDattr(synIDtrans(hlID('Normal')), 'bg', 'cterm')
+    if bg_color !=# ''
+      if bg_color < 8 || 232 <= bg_color && bg_color < 244
+        return 'dark'
+      elseif 8 <= bg_color && bg_color < 16 || 244 <= bg_color
+        return 'light'
+      endif
+    endif
+    let fg_color = synIDattr(synIDtrans(hlID('Normal')), 'fg', 'cterm')
+    if fg_color !=# ''
+      if fg_color < 8 || 232 <= fg_color && fg_color < 244
+        return 'light'
+      elseif 8 <= fg_color && fg_color < 16 || 244 <= fg_color
+        return 'dark'
+      endif
+    endif
+    return &background
+  endfunction
+endif
+
 let &cpo = s:save_cpo
 unlet s:save_cpo

autoload/lightline/colorscheme/16color.vim

@@ -2,8 +2,9 @@
 " Filename: autoload/lightline/colorscheme/16color.vim
 " Author: itchyny
 " License: MIT License
-" Last Change: 2014/01/02 10:04:03.
+" Last Change: 2017/11/25 11:14:04.
 " =============================================================================
+
 let s:base03 = [ '#808080', 8 ]
 let s:base02 = [ '#000000', 0 ]
 let s:base01 = [ '#00ff00', 10 ]
@@ -20,12 +21,14 @@ let s:violet = [ '#ff00ff', 13 ]
 let s:blue = [ '#000080', 4 ]
 let s:cyan = [ '#008080', 6 ]
 let s:green = [ '#008000', 2 ]
-if &background ==# 'light'
+
+if lightline#colorscheme#background() ==# 'light'
   let [s:base03, s:base3] = [s:base3, s:base03]
   let [s:base02, s:base2] = [s:base2, s:base02]
   let [s:base01, s:base1] = [s:base1, s:base01]
   let [s:base00, s:base0] = [s:base0, s:base00]
 endif
+
 let s:p = {'normal': {}, 'inactive': {}, 'insert': {}, 'replace': {}, 'visual': {}, 'tabline': {}}
 let s:p.normal.left = [ [ s:base3, s:blue ], [ s:base3, s:base01 ] ]
 let s:p.normal.right = [ [ s:base02, s:base0 ], [ s:base1, s:base01 ] ]

autoload/lightline/colorscheme/PaperColor.vim

@@ -2,10 +2,10 @@
 " Filename: autoload/lightline/colorscheme/PaperColor.vim
 " Author: TKNGUE
 " License: MIT License
-" Last Change: 2015/07/28 07:35:00.
+" Last Change: 2017/11/25 11:13:35.
 " =============================================================================
 
-if &background ==# 'light'
+if lightline#colorscheme#background() ==# 'light'
   let g:lightline#colorscheme#PaperColor#palette = g:lightline#colorscheme#PaperColor_light#palette
 else
   let g:lightline#colorscheme#PaperColor#palette = g:lightline#colorscheme#PaperColor_dark#palette

autoload/lightline/colorscheme/materia.vim

@@ -2,7 +2,7 @@
 " Filename: autoload/lightline/colorscheme/materia.vim
 " Author: Lokesh Krishna
 " License: MIT License
-" Last Change: 2017/10/21 11:32:27.
+" Last Change: 2017/11/25 11:13:40.
 " =============================================================================
 
 " Common colors
@@ -16,7 +16,7 @@ let s:yellow = '#ffcc00'
 
 let s:p = {'normal': {}, 'inactive': {}, 'insert': {}, 'replace': {}, 'visual': {}, 'tabline': {}}
 
-if &background ==# 'light'
+if lightline#colorscheme#background() ==# 'light'
   " Light variant
   let s:bg     = '#ffffff'
   let s:gray1  = '#2c393f'

autoload/lightline/colorscheme/material.vim

@@ -2,7 +2,7 @@
 " Filename: autoload/lightline/colorscheme/material.vim
 " Author: Lokesh Krishna
 " License: MIT License
-" Last Change: 2017/10/30 16:35:27.
+" Last Change: 2017/11/25 11:13:42.
 " =============================================================================
 
 " Common colors
@@ -16,7 +16,7 @@ let s:yellow = '#ffcb6b'
 
 let s:p = {'normal': {}, 'inactive': {}, 'insert': {}, 'replace': {}, 'visual': {}, 'tabline': {}}
 
-if &background ==# 'light'
+if lightline#colorscheme#background() ==# 'light'
   " Light variant
   let s:bg     = '#ffffff'
   let s:gray1  = '#2e3c43'

autoload/lightline/colorscheme/one.vim

@@ -2,7 +2,7 @@
 " Filename: autoload/lightline/colorscheme/one.vim
 " Author: Zoltan Dalmadi
 " License: MIT License
-" Last Change: 2016/11/2 17:34:27.
+" Last Change: 2017/11/25 11:13:44.
 " =============================================================================
 
 " Common colors
@@ -16,7 +16,7 @@ let s:yellow = '#e5c07b'
 
 let s:p = {'normal': {}, 'inactive': {}, 'insert': {}, 'replace': {}, 'visual': {}, 'tabline': {}}
 
-if &background ==# 'light'
+if lightline#colorscheme#background() ==# 'light'
   " Light variant
   let s:bg     = '#fafafa'
   let s:gray1  = '#494b53'

autoload/lightline/colorscheme/solarized.vim

@@ -2,7 +2,7 @@
 " Filename: autoload/lightline/colorscheme/solarized.vim
 " Author: itchyny
 " License: MIT License
-" Last Change: 2016/08/08 10:31:00.
+" Last Change: 2017/11/25 11:13:46.
 " =============================================================================
 
 let s:cuicolors = {
@@ -53,7 +53,7 @@ let s:blue = [ '#268bd2', s:cuicolors.blue[s:cuiindex] ]
 let s:cyan = [ '#2aa198', s:cuicolors.cyan[s:cuiindex] ]
 let s:green = [ '#859900', s:cuicolors.green[s:cuiindex] ]
 
-if &background ==# 'light'
+if lightline#colorscheme#background() ==# 'light'
   let [ s:base03, s:base3 ] = [ s:base3, s:base03 ]
   let [ s:base02, s:base2 ] = [ s:base2, s:base02 ]
   let [ s:base01, s:base1 ] = [ s:base1, s:base01 ]