" -------------------------------
" Global options
" -------------------------------

"colorscheme ice
colorscheme default

" Colors
if has('termguicolors')
  set termguicolors
endif

" Cursor can rest beyond the last character
set virtualedit=onemore

" Highlight
set hlsearch

" Options
syntax on
set nowrap
set number
set relativenumber
set tabstop=8
set shiftwidth=8
set softtabstop=8
set noexpandtab
set autoindent
set smartindent
set scrolloff=999
set mouse=a


" Line numbers
hi LineNr       ctermfg=7 ctermbg=NONE guifg=#505050 guibg=NONE
hi CursorLineNr ctermfg=7 ctermbg=NONE guifg=#505050 guibg=NONE


" -------------------------------
" Toggle between default and kernel-style settings
" -------------------------------

let g:vim_kernel_mode = 1  " 0 = personal, 1 = kernel

function! ToggleListStyle()
    if g:vim_kernel_mode
        " Kernel style settings
        set list               " show tabs, trailing spaces, eol
        set listchars=tab:>-,trail:~,eol:$
        let g:vim_list_mode = 1
        echo "List mode"
    else
        " Restore your personal settings
        set nolist
        set listchars=
        let g:vim_list_mode = 0
        echo "No list mode"
    endif
    " toggle the mode for next call
    let g:vim_kernel_mode = !g:vim_kernel_mode
endfunction


" -------------------------------
" Statusbar
" -------------------------------

function! VisualModeLineCount()
  if mode() =~# 'v'
    return '['.(line("'>") - line("'<") + 1).' lines selected]'
  endif
  return ''
endfunction

function! ModifiedFlag()
  if &modified
    return '[Modified]'    " Your custom text
  endif
  return ''                 " Empty if not modified
endfunction

function! ReadOnlyFlag()
  if &readonly
    return '[Read-only]'    " Your custom text
  endif
  return ''                 " Empty if not modified
endfunction


" Function to display current column / total columns in current line
function! ColAndTotal()
  return printf('%d/%d', col('.'), col('$'))
endfunction

" Full-width statusline
set laststatus=2

" LEFT Side
set statusline=
set statusline+=%f                          " File name
set statusline+=\ [%l:%{ColAndTotal()}]     " Line and column / total columns
set statusline+=\ [%L/%p%%]                 " Total lines and percent
set statusline+=%{VisualModeLineCount()}    " Selected lines in visual mode
set statusline+=%{ModifiedFlag()}           " Custom modified flag

" CENTER filler (optional)
set statusline+=%=

" RIGHT side
set statusline+=\ [%y]                      " Filetype
set statusline+=%{ReadOnlyFlag()}

" Status bar transparent
hi StatusLine ctermbg=0 cterm=NONE

" Disable expandtab for make files
autocmd FileType make setlocal noexpandtab

" System clipboard
if has("clipboard")
  set clipboard=unnamedplus
endif

" ===============================
" Kernel-style 80-column guide for C files
" ===============================

" Use ftplugin for C files only
augroup c_kernel_style
    autocmd!

    " Trigger for C files
    autocmd FileType c call s:kernel_c_setup()
augroup END

function! s:kernel_c_setup()
    " Highlight the 80th column
    setlocal colorcolumn=80

    " Optional: show cursor position
    setlocal ruler

    " Optional: soft wrap for comments
    "setlocal textwidth=80
    "setlocal formatoptions+=t

    " Optional: subtle color for colorcolumn (works in GUI or truecolor terminals)
    hi ColorColumn ctermbg=236 guibg=#3a3a3a
endfunction


" -------------------------------
" Keymaps
" -------------------------------

" F2: toggle all numbers
nnoremap <F2> :if &number \| set nonumber norelativenumber \| else \| set number relativenumber \| endif<CR>

" F4: absolute numbers only
"nnoremap <F4> :set relativenumber!<CR>

" F5: Search highlight
nnoremap <F5> :nohlsearch<CR>

" F6: to toggle kernel style
nnoremap <F6> :call ToggleListStyle()<CR>

" F7: remove all trailing line
nnoremap <F7> :%s/\s\+$//e<CR>

" F8 will run checkpatch.pl and populate quickfix list
nnoremap <F8> :w<CR>:cexpr system('checkpatch.pl --no-tree --file ' . expand('%:p'))<CR>:cwindow<CR>

" Quickfix navigation with Shift + > / Shift + <
" Note: Vim sees these as > and < in normal mode
nnoremap > :cnext<CR>
nnoremap < :cprev<CR>

if &term =~ 'tmux\|xterm\|konsole'
  " Map HOME key to move to beginning of line in normal mode
  noremap <Esc>[1~ 0
  noremap <Esc>[H 0
  noremap <Esc>OH 0
endif