" if without, nvim with no file will give error because it's not defined?
let fenc_bef = 0

" https://github.com/junegunn/vim-plug
call plug#begin()
" https://github.com/junegunn/fzf.vim#commands
" seems only need junegunn/fzf.vim, no need junegunn/fzf if already installed fzf with pacman
"Plug 'junegunn/fzf', { 'do': { -> fzf#install() } }
"Plug 'junegunn/fzf.vim'
"Plug 'vim-perl/vim-perl', { 'for': 'perl', 'do': 'make clean carp dancer highlight-all-pragmas moose test-more try-tiny' }
if has('nvim') && executable('firefox')
	Plug 'glacambre/firenvim', { 'do': { _ -> firenvim#install(0) } }
endif
" tinted-theming/base16-vim has low contrast on fold title make it unreadable, but I customized it easily
" chriskempson/base16-vim doesn't do bold/italic for markdown syntax, and not maintained
" RRethy/base16-nvim does not highlight markdown codeblocks
" tinted-theming/base16-vim and RRethy/base16-nvim seem both work, both support tree-sitter
Plug 'tinted-theming/base16-vim'
" nvim-treesitter seems support markdown highlight now, run `:TSEnable highlight`, more see vc notes
" but very slow when editing large markdown files so I sitll don't enable it, maybe related:
" https://github.com/nvim-treesitter/nvim-treesitter/issues/2206
"Plug 'nvim-treesitter/nvim-treesitter', {'do': ':TSUpdate'}  " We recommend updating the parsers on update
" use latest vim-markdown
"Plug 'tpope/vim-markdown'
" alternatives: h-hg/fcitx.nvim, rlue/vim-barbaric, lilydjwg/fcitx.vim
" h-hg/fcitx.nvim is the only one out of the three alternatives that does not
" have this issue: after / search with chinese pingyin, then enter, then in
" normal mode if I press one key, e.g., k, it will trying to use chinese
" pingyin instead of using english
if executable('fcitx5')
	Plug 'h-hg/fcitx.nvim'
endif
" alternatives: 'thinca/vim-ref' with 'eiiches/vim-ref-info', 'HiPhish/info.vim', 'alx741/vinfo'
Plug 'https://gitlab.com/HiPhish/info.vim.git'
" :h hexmode
" other related doc: :h hex-editing, :h 23.3, :h edit-binary
if executable('xxd')
	Plug 'fidian/hexmode'
endif
call plug#end()

" next line must put below `Plug 'glacambre/firenvim'`, else if click github issue textarea, then click elsewhere, then click textarea, textarea will not be selected (no cursor in it), not sure why
let g:firenvim_config = { 'localSettings': { '.*': { 'takeover': 'never' } } }

let g:infoprg = '/usr/bin/info'

" I use only one return for better readability
function! Autocmd_set_fenc() abort
	" need to test &modifiable for gO
	if &modifiable && (&fileencoding != "utf-8")
		let l:fenc_bef = &fileencoding
		setlocal fileencoding=utf-8
		unsilent echom ":w to rewrite as utf-8"
		return l:fenc_bef
	else
		return &fileencoding
	endif
endfunction

function! Md_toggle_fold() abort
	" &markdown_folding won't work because markdown_folding is not an option
	" two ways to check if g:markdown_folding variable exists and is true:
	" more see https://stackoverflow.com/q/15864164/9008720
	"if exists('g:markdown_folding') && g:markdown_folding
	if get(g:, 'markdown_folding')
		let g:markdown_folding=0
		" :e
		e
	else
		let g:markdown_folding=1
		e
	endif
endfunction

" not fully understood augroup, recommanded in :help
" https://www.youtube.com/watch?v=dBBUOO1PRIU
augroup mycmd
	autocmd!
	" disable auto line break (tc) and insert comment (cro)
	autocmd FileType * setlocal formatoptions-=c formatoptions-=r formatoptions-=o formatoptions-=t
	" auto rewrite as utf-8 if not when :w
	" if use FileType *, nvim can't recognize some file extensions, ex: .csv
	autocmd BufRead * let fenc_bef = Autocmd_set_fenc()
	" similar to filetype.vim code, use setfiletype
	" .csx seems not c# but c# script file, this works tho
	" set syntax=cs also works
	autocmd BufNewFile,BufRead *.csx setfiletype cs
	" https://stackoverflow.com/q/28310094 multi filetypes
	" for alerting me plain text email characters per line
	" neomutt auto set new email filetype as mail so this will work
	" /usr/share/nvim/runtime/ftplugin/mail.vim default textwidth 72
	" https://stackoverflow.com/q/2290016 suggest gitcommit main body should be about 72
	" https://useplaintext.email/ suggest 72
	" https://mailformat.dan.info/body/linelength.html suggested 65
	"" https://superuser.com/q/827647/1282809
	" https://lkml.org shows Linus seems use 70
	" https://lkml.org Hottest messages shows people use around 70-80
	" https://en.wikipedia.org/wiki/Characters_per_line
	" related: textwidth
	" if want to do this only for some file extensions, see:
	"" https://stackoverflow.com/a/469576/9008720
	"" don't forget to put in augroup:
	"" https://stackoverflow.com/a/60470085/9008720
	"" also other ways:
	"" https://stackoverflow.com/q/158968/9008720
	" or use setlocal cc=
	autocmd FileType mail,gitcommit setlocal colorcolumn=72
	" open file readonly if it already been open
	" nvim seems change default from '' to 'e', but I prefer 'o'
	" :h w325 e325 SwapExists swapchoice default-autocmds
	" https://vi.stackexchange.com/questions/21784/vim-edit-anyway-without-prompting
	" https://github.com/neovim/neovim/pull/25336
	" https://github.com/neovim/neovim/commit/29fe883aa9166bdbcae3f935523c75a8aa56fe45
	" remove nvim.swapfile autocmd is more correct, without also works but I think it change to 'e' then to 'o' which is not ideal, also it will echo "W325: ..." which is not what I want
	autocmd! nvim.swapfile
	autocmd SwapExists * let v:swapchoice = 'o'
augroup END

" :h markdown, for vim default tpope/vim-markdown
" enable markdown fold will make opening large files slower, so I don't enable it
"let g:markdown_folding = 1
" g:markdown_minlines before nvim 0.8, 500 works well; version 0.8 makes even 400 noticeable slow when keep pressing gk
let g:markdown_minlines = 350
"let g:markdown_fenced_languages = ['python', 'sh', 'vim', 'c', 'cpp']

" :h hexmode, fidian/hexmode plugin
" imagemagick .gray file format
let g:hexmode_patterns = '*.gray'
map <leader>h :Hexmode<CR>
"let g:hexmode_xxd_options = '-c 32'

" netrw-p preview vertial split
let g:netrw_preview = 1
let g:netrw_winsize = 20

" seems needs this for autocmd FileType * to work? 
filetype plugin on

" fold is slow and buggy, at least for different kinds of vim-markdown, disable it, not sure if works or not
"set nofoldenable

language en_US
set number relativenumber

" need next line for base16 colorscheme to work?
set termguicolors
colorscheme base16-tomorrow-night

" set dir to current editing file's dir 
set autochdir

" Spaces & Tabs
set tabstop=4       " number of visual spaces per TAB
set softtabstop=4   " number of spaces in tab when editing
set shiftwidth=4    " number of spaces to use for autoindent
"set expandtab       " tabs are space

" https://www.zhihu.com/question/22363620/answer/21199296
" euc-cn=gb2312, cp936=gbk
" it is recommended by `:h fileencodings` to put ucs-bom at first and latin1 at last
" based on my experience, if put utf-16 in front of euc-cn, euc-cn will have mojibake
" based on my experience, if put big5 in front of euc-cn and cp936, euc-cn will have mojibake
" according to zhihu comment, if put gb18030 in front of big5 , big5 will have mojibake
" according to wikipedia articles, euc-cn is preceded by cp936 which is preceded by gb18030, gb18030 is backward compatible with cp936 which seems is backward compatible with euc-cn
set fileencodings=ucs-bom,utf-8,euc-cn,cp936,big5,gb18030,utf-16,latin1
" seems is default to neovim but not vim
set encoding=utf-8

" some file on win10 display as unix but is dos
if has('win32')
	set fileformats=dos
	" windows 10 bug, need this to change cursor back to vertical bar after leaving neovim
	" the number after ver seems no effects, maybe because neovim is exited
	" https://github.com/alacritty/alacritty/issues/2839#issuecomment-766421840
	" use of ! after autocmd see youtube video above, not fully understood
	autocmd! VimLeave * set guicursor=a:ver25
endif

" if don't want to generate swap file
"set noswapfile
" nvim backup file defualt off, see `:h nobackup` `:set backup?`
" nvim undo file default off, see `:h noundofile` `:set undofile?`

" gg=G work for .xml files now,:h matchit-activate
" https://stackoverflow.com/questions/21408222/vim-indent-xml-file/28365920#28365920
packadd! matchit

" search case sensitive only if have uppercase
set ignorecase
set smartcase

" disable mouse support
" :h disable-mouse
set mouse=

" map ctrl+h/j/k/l to move between split windows
map <C-h> <C-w>h
map <C-j> <C-w>j
map <C-k> <C-w>k
map <C-l> <C-w>l

" moving in long line
"nnoremap k gk
"nnoremap j gj

nnoremap o o<Esc>
nnoremap O O<Esc>

" maybe useful if use mapleader in the future: https://www.slant.co/topics/7423/~which-key-works-best-as-vim-leader
" for searching command in manpages
map <leader>- /^ *-
map <leader>* /\*\*.*\*\*<CR>
" toggle markdown folding and re-edit current file
map <leader>m :call Md_toggle_fold()<CR>

" default statusline:set statusline=%<%f\ %h%m%r%=%-14.(%l,%c%V%)\ %P
set statusline+=%<
set statusline+=%f          " %F or 1CTRL+G to show full path
set statusline+=\ %m
set statusline+=%=
" https://stackoverflow.com/questions/5375240/a-more-useful-statusline-in-vim#comment84812779_10416234
" :h eol-and-eof
" show if there's newline at end of file
set statusline+=%{&eol?'':'noeol'}
set statusline+=\ %y
"set statusline+=\ %{&fileencoding?&fileencoding:&encoding}
" below line doesn't work as expected, not sure why
"set statusline+=\ %{fenc_bef?fenc_bef:&fileencoding}
set statusline+=\ %{fenc_bef}
set statusline+=\ \[%{&fileformat}\]
set statusline+=\ %-10.(%l,%c%V%)
set statusline+=\ %P