.vimrc.lite

" ============================================================================
" Vim Lite Configuration — Zero Plugins Required
" Author: George Gozal
" All features use vim built-ins only. No :PlugInstall needed.
" Usage: vim -u ~/.vimrc.lite  OR  copy to ~/.vimrc on a fresh machine
" ============================================================================

" Required when loading with vim -u (skips defaults.vim)
set nocompatible
set backspace=indent,eol,start

" ============================================================================
" TERMINAL & COLOR COMPATIBILITY
" ============================================================================

let s:is_mac = has('mac') || has('macunix')

function! s:HasTrueColor() abort
    if !has('termguicolors')
        return 0
    endif
    if s:is_mac && $TERM_PROGRAM ==# 'Apple_Terminal'
        return 0
    endif
    return $COLORTERM ==# 'truecolor' || $COLORTERM ==# '24bit'
        \ || $TERM_PROGRAM ==# 'iTerm.app'
        \ || $TERM_PROGRAM ==# 'vscode'
        \ || $TERM =~# 'direct'
        \ || $TERM =~# 'kitty'
        \ || $TERM =~# 'wezterm'
        \ || $TERM =~# 'alacritty'
endfunction

let s:use_termguicolors = s:HasTrueColor()
if s:use_termguicolors
    set termguicolors
else
    set notermguicolors
    if &t_Co < 256 && ($TERM =~# '256color' || $TERM =~# 'xterm')
        set t_Co=256
    endif
endif

function! s:ApplyUiHighlights() abort
    if s:use_termguicolors
        highlight CursorLine   guibg=#303030
        highlight CursorLineNr guifg=#ffff00
        highlight LineNr       guifg=#585858
        highlight StatusLine   guibg=#262626 guifg=#ffffff
        highlight StatusLineNC guibg=#262626 guifg=#808080
    elseif &t_Co >= 256
        highlight CursorLine   cterm=NONE ctermbg=236
        highlight CursorLineNr ctermfg=226 cterm=bold
        highlight LineNr       ctermfg=243
        highlight Normal       ctermfg=252 ctermbg=234
        highlight StatusLine   cterm=bold ctermfg=15 ctermbg=236
        highlight StatusLineNC ctermfg=246 ctermbg=236
    else
        highlight CursorLine   cterm=underline
        highlight CursorLineNr ctermfg=Yellow cterm=bold
        highlight LineNr       ctermfg=Cyan
        highlight StatusLine   cterm=bold ctermfg=White ctermbg=Black
        highlight StatusLineNC ctermfg=Grey ctermbg=Black
    endif
endfunction

if s:is_mac
    set clipboard=unnamed
else
    if has('clipboard')
        set clipboard=unnamedplus
    else
        autocmd TextYankPost * call system('xclip -selection clipboard', @")
        nnoremap p :let @"=system('xclip -selection clipboard -o')<CR>p
        nnoremap P :let @"=system('xclip -selection clipboard -o')<CR>P
    endif
endif

" ============================================================================
" GENERAL SETTINGS
" ============================================================================

filetype plugin indent on
syntax on

set number
set relativenumber
set tabstop=4
set shiftwidth=4
set expandtab
set cursorline
set autoindent
set nowrap
set ignorecase
set smartcase
set incsearch
set hlsearch
set backspace=indent,eol,start
set mouse=a
set encoding=utf-8
set background=dark

" ============================================================================
" BETTER DEFAULTS
" ============================================================================

set hidden
set splitright
set splitbelow
set undofile
set undodir=~/.vim/undodir
set wildmenu
set wildmode=list:longest,full
set showcmd
set showmatch
set matchtime=2
set history=1000
set updatetime=300
set lazyredraw
set completeopt=menuone,noinsert,noselect
set shortmess+=c
set noswapfile
set nobackup

" ============================================================================
" COLORSCHEME (built-in)
" ============================================================================

colorscheme desert
call s:ApplyUiHighlights()
syntax enable

" ============================================================================
" BUILT-IN STATUS LINE (replaces vim-airline)
" ============================================================================

set laststatus=2
set statusline=
set statusline+=\ %f                   " file path
set statusline+=\ %m%r                 " modified/readonly flags
set statusline+=%=                     " right align
set statusline+=\ %y                   " filetype
set statusline+=\ [%{&fileencoding}]   " encoding
set statusline+=\ %l:%c               " line:column
set statusline+=\ [%p%%]              " percentage

" ============================================================================
" BUILT-IN FILE EXPLORER (replaces NERDTree)
" ============================================================================

" netrw is built into vim — use :Explore or :Vexplore
let g:netrw_banner = 0         " hide banner
let g:netrw_liststyle = 3      " tree view
let g:netrw_browse_split = 4   " open in previous window
let g:netrw_altv = 1           " open splits to the right
let g:netrw_winsize = 25       " 25% width

" Toggle netrw sidebar with Ctrl+n
nnoremap <C-n> :Lexplore<CR>

" :Tree command (same as full .vimrc)
command! Tree Lexplore

" Open netrw as a proper sidebar when vim starts with a directory argument
" This prevents 'vim .' from putting netrw in the main window, which would
" cause Ctrl+n to open a duplicate sidebar
autocmd StdinReadPre * let s:std_in=1
autocmd VimEnter * if argc() == 1 && isdirectory(argv()[0]) && !exists('s:std_in') |
    \ execute 'cd' fnameescape(argv()[0]) | enew | Lexplore | endif


" ============================================================================
" BUILT-IN FUZZY FIND (replaces ctrlp)
" ============================================================================

" Search recursively in subdirectories
set path+=**

" :find <filename> now works with tab completion across the project
" :b <partial> switches buffers with tab completion

" ============================================================================
" BUILT-IN COMMENTING (replaces vim-commentary)
" ============================================================================

" Toggle comment with <leader>c in normal and visual mode
" Uses filetype-aware comment strings
augroup commenting
    autocmd!
    autocmd FileType python,sh,bash,zsh,yaml let b:comment_prefix = '# ' | let b:comment_suffix = ''
    autocmd FileType javascript,java,c,cpp   let b:comment_prefix = '// ' | let b:comment_suffix = ''
    autocmd FileType vim                      let b:comment_prefix = '" ' | let b:comment_suffix = ''
    autocmd FileType html,xml                 let b:comment_prefix = '<!-- ' | let b:comment_suffix = ' -->'
augroup END

function! ToggleComment() range
    let l:prefix = get(b:, 'comment_prefix', '# ')
    let l:suffix = get(b:, 'comment_suffix', '')
    let l:lines = getline(a:firstline, a:lastline)
    let l:uncomment = 0
    for l:line in l:lines
        if l:line =~ '^\s*$' | continue | endif
        if l:line =~ '^\s*' . escape(l:prefix, '/*')
            let l:uncomment = 1
        endif
        break
    endfor
    for l:lnum in range(a:firstline, a:lastline)
        let l:line = getline(l:lnum)
        if l:line =~ '^\s*$' | continue | endif
        if l:uncomment
            if !empty(l:suffix)
                call setline(l:lnum, substitute(l:line, '^\(\s*\)' . escape(l:prefix, '/*') . '\(.*\)' . escape(l:suffix, '/*') . '\s*$', '\1\2', ''))
            else
                call setline(l:lnum, substitute(l:line, '^\(\s*\)' . escape(l:prefix, '/*'), '\1', ''))
            endif
        else
            if !empty(l:suffix)
                call setline(l:lnum, substitute(l:line, '^\(\s*\)\(.*\)\s*$', '\1' . l:prefix . '\2' . l:suffix, ''))
            else
                call setline(l:lnum, substitute(l:line, '^\(\s*\)', '\1' . escape(l:prefix, '&'), ''))
            endif
        endif
    endfor
endfunction

nnoremap <leader>c :call ToggleComment()<CR>
vnoremap <leader>c :call ToggleComment()<CR>

" ============================================================================
" KEY MAPPINGS
" ============================================================================

nnoremap <C-s> :w<CR>
nnoremap <C-q> :q<CR>
nnoremap <leader>h :nohlsearch<CR>
nnoremap j gj
nnoremap k gk
inoremap jk <Esc>

nnoremap <C-j> :m .+1<CR>==
nnoremap <C-k> :m .-2<CR>==
vnoremap <C-j> :m '>+1<CR>gv=gv
vnoremap <C-k> :m '<-2<CR>gv=gv

if !s:is_mac || $TERM_PROGRAM ==# 'iTerm.app'
    nnoremap <M-j> :m .+1<CR>==
    nnoremap <M-k> :m .-2<CR>==
    vnoremap <M-j> :m '>+1<CR>gv=gv
    vnoremap <M-k> :m '<-2<CR>gv=gv
endif

" ============================================================================
" BUFFER & WINDOW NAVIGATION
" ============================================================================

nnoremap <leader>n :bnext<CR>
nnoremap <leader>p :bprev<CR>
nnoremap <leader>d :bdelete<CR>
nnoremap <leader>b :ls<CR>:b<Space>
nnoremap <leader>1 :b1<CR>
nnoremap <leader>2 :b2<CR>
nnoremap <leader>3 :b3<CR>
nnoremap <leader>4 :b4<CR>
nnoremap <leader>5 :b5<CR>
nnoremap <leader>x :bp<bar>sp<bar>bn<bar>bd<CR>
nnoremap <leader>v :vsplit<CR>
nnoremap <leader>s :split<CR>
nnoremap <leader>w :w<CR>
nnoremap <leader>q :q<CR>

" Keep visual selection after indent
vnoremap < <gv
vnoremap > >gv


" ============================================================================
" BUILT-IN BUFFER TABLINE (replaces vim-buftabline)
" ============================================================================

" Show tabline when 2+ buffers open
set showtabline=2

function! BufTabLine()
    let s = ''
    for i in range(1, bufnr('$'))
        if buflisted(i)
            let name = fnamemodify(bufname(i), ':t')
            if empty(name) | let name = '[No Name]' | endif
            if i == bufnr('%')
                let s .= ' %#TabLineSel# ' . name . ' '
            else
                let s .= ' %#TabLine# ' . name . ' '
            endif
        endif
    endfor
    return s . '%#TabLineFill#'
endfunction

set tabline=%!BufTabLine()

" ============================================================================
" FILE TYPE SPECIFIC SETTINGS
" ============================================================================

autocmd FileType python     setlocal shiftwidth=4 tabstop=4
autocmd FileType javascript setlocal shiftwidth=2 tabstop=2
autocmd FileType html       setlocal shiftwidth=2 tabstop=2
autocmd FileType sh         setlocal shiftwidth=4 tabstop=4
autocmd FileType xml        setlocal shiftwidth=2 tabstop=2
autocmd FileType json       setlocal shiftwidth=2 tabstop=2
autocmd FileType yaml       setlocal shiftwidth=2 tabstop=2

" ============================================================================
" AUTO-CLEANUP
" ============================================================================

" Remove trailing whitespace on save for Python and shell scripts
autocmd BufWritePre *.py,*.sh,*.bash %s/\s\+$//e

" ============================================================================
" INITIALIZATION
" ============================================================================

if !isdirectory($HOME."/.vim/undodir")
    call mkdir($HOME."/.vim/undodir", "p", 0700)
endif