vim termux fixes

" encoding fix, for russian, hopefuly universal
set enc=utf-8
set fileencoding=utf-8
set fileencodings=ucs-bom,utf8,prc
set guifont=Monaco:h11
set guifontwide=NSimsun:h12

" indent fix, tab shown as 1 space, pc-friendly
set nocindent
set nosmartindent
set nosmarttab
set noexpandtab
set shiftwidth=1
set softtabstop=1
set tabstop=1
set ignorecase
filetype indent off

" fix for navigation like in all other editors
nnoremap <expr> <Up> (v:count == 0 ? 'gk' : 'k')
nnoremap <expr> <Down> (v:count == 0 ? 'gj' : 'j')
inoremap <expr> <silent> <Up>   pumvisible() ? "\<Up>" : "\<C-o>gk"
inoremap <expr> <silent> <Down> pumvisible() ? "\<Down>" : "\<C-o>gj"
set whichwrap+=<,>,h,l,[,],b,s

" copy-paste fix. also do both:
" pkg install termux-api
" google play download 'termux api'
nnoremap <C-c> :'<,'>w !termux-clipboard-set<CR>
nnoremap <C-v> :r !termux-clipboard-get<CR>

" text and code folding, no special symbols
" 1 new line = same foldlevel
" 2 new lines = increase foldlevel
" 3 new lines = decrease foldlevel
let b:ind=0
let b:progress=0
let b:newlines=0
set foldmethod=expr
set foldexpr=VimFoldLevel(v:lnum)
function! VimFoldLevel(line)
    if(b:progress<=a:line)
        let b:progress=a:line else return endif
    if getline(a:line) =~ '^[ \t]*$'
        let b:newlines=b:newlines+1
        if b:newlines==2
            return b:ind+1
        endif
        if b:newlines==3
            let b:ind=max([b:ind-1,0])
        endif
        return b:ind
    else
        if b:newlines==2
            let b:ind=b:ind+1
        endif
        let b:newlines=0
        return b:ind+1
    endif
endfunction