" Autoload funtions for custom statusbar.
" Last Changed: 2021-09-29
" Author: Federico Igne <>
" License: This file is placed in the public domain.

" Highlight statusbar if current buffer contains unsaved changes.
function! dyamon#statusline#setcolor() abort
    if getbufvar(bufnr('%'), '&modified')
        highlight User3 ctermbg=3 guibg=#d79921
    else
        highlight User3 ctermbg=248 guibg=#bdae93
    endif
    " Force statusline update
    setlocal statusline=
    " Overrides default return value (0) that would be displayed in the
    " statusbar
    return ''
endfunction

function! dyamon#statusline#modeflag() abort
    " The preview window is an exception among exceptions
    if &previewwindow && has_key(g:specialFlag, 'preview')
        return g:specialFlag.preview
    endif
    " Compute the correct flag
    let l:flag=get( g:nameFlag,
                  \ expand('%'),
                  \ get( g:filetypeFlag,
                       \ &filetype,
                       \ get(g:modeFlag, mode(), 'Err')
                       \ )
                  \ )
    return l:flag
endfunction

function! dyamon#statusline#fileprefix() abort
  let l:basename=expand('%:h')
  if l:basename ==# '' || l:basename ==# '.'
    return ''
  elseif winwidth(0) > g:fullstatusline
    return substitute(l:basename . '/', '\C^' . $HOME, '~', '')
  else
    return ''
  endif
endfunction

" Return session flag, if an active (Ob)session is detected.
function! dyamon#statusline#session() abort
    let l:session_flag = ['s', 'S']
    let l:numeric = !empty(v:this_session) + exists('g:this_obsession')
    if l:numeric
        return ',' . l:session_flag[l:numeric-1]
    else
      return ''
    endif
endfunction

" Return filetype (if any).
function! dyamon#statusline#filetype() abort
  if strlen(&ft) && !has_key(g:filetypeFlag,&ft)
    return ',' . &ft
  else
    return ''
  endif
endfunction

" Return file encoding if different from default (utf8).
function! dyamon#statusline#fileenc() abort
  if strlen(&fenc) && &fenc !=# 'utf-8' && winwidth(0) > g:fullstatusline
    return ',' . &fenc
  else
    return ''
  endif
endfunction

" Return git related info (if GitGutter is active provide additional info
" about changed hunks in the current buffer)
function! dyamon#statusline#gitinfo() abort
    let l:git = ' '
    let l:head = ''
    if exists('*FugitiveHead') && len(FugitiveHead(8))
        let l:head = FugitiveHead(8)
        let l:git .= ' ' . l:head . ' '
    endif
    if len(l:head) &&
     \ exists('g:gitgutter_enabled') && g:gitgutter_enabled &&
     \ winwidth(0) ># g:fullstatusline
        let l:s = GitGutterGetHunkSummary()
        let l:git .= len(l:s) ? printf('(+%d ~%d -%d) ', l:s[0], l:s[1], l:s[2]) : ''
    endif
    return l:git
endfun

" If a language server is registered and enabled (via `vim-lsp` plugin)
" add a custom indicator.
function! dyamon#statusline#lsp() abort
    " Manually detect the server name based on the filetype
    let l:servers = {
        \ 'scala' : 'metals',
        \ 'sbt' : 'metals'
        \}
    " Indicators
    let l:indicators = {
        \ 'unknown server' : ' ',
        \ 'exited'         : ' ',
        \ 'starting'       : ' ',
        \ 'failed'         : ' ',
        \ 'running'        : ' ',
        \ 'not running'    : ' ',
        \ 'hint'           : ' ',
        \ 'information'    : ' ',
        \ 'warning'        : ' ',
        \ 'error'          : ' '
        \}
    let l:server = get(l:servers, &filetype, '')
    if len(l:server)
        let l:status = lsp#get_server_status(l:server)
        let l:prefix = '▕ '
        if l:status ==# 'running'
            " Get language server counts
            let l:counts = lsp#get_buffer_diagnostics_counts() 
            let l:hint = get(l:counts, 'hint', 0)
            let l:info = get(l:counts, 'information', 0)
            let l:warn = get(l:counts, 'warning', 0)
            let l:erro = get(l:counts, 'error', 0)
            " Build output
            let l:output = ''
            if l:hint > 0
                let l:output .= get(l:indicators,'hint') . l:hint . ' '
            endif
            if l:info > 0
                let l:output .= get(l:indicators,'information') . l:info . ' '
            endif
            if l:warn > 0
                let l:output .= get(l:indicators,'warning') . l:warn . ' '
            endif
            if l:erro > 0
                let l:output .= get(l:indicators,'error') . l:erro . ' '
            endif
            if len(l:output)
                return  l:prefix . l:output
            else
                return l:prefix . get(l:indicators, l:status) . ' '
            endif
        else
            return l:prefix . get(l:indicators, l:status) . ' '
        endif
    else
        return ''
    endif
endfun

" Blur statusline
function! dyamon#statusline#blur() abort
  if ! exists("b:disable_statusline")
    let l:blurred='\ '  " space
    let l:blurred.='%<' " truncation point
    let l:blurred.='%f' " filename
    let l:blurred.='%=' " split left/right halves (makes background cover whole)
    execute 'setlocal statusline=' . l:blurred
  endif
endfunction

" Focus statusline
function! dyamon#statusline#focus() abort
  if ! exists("b:disable_statusline")
    " Reset to global option
    setlocal statusline=
  endif
endfunction

" Custom function for the TagBar plugin
function! dyamon#statusline#tagbar(current, sort, fname, flags, ...) abort
    " Initialise custom statusline
    let l:statusline = ''
    if a:current
        " Tagbar label is always set to 'unmodified' color
        highlight User3 cterm=bold ctermfg=18 ctermbg=20
        " 'TagBar' label
        let l:statusline .= '%3* TagBar '
        " Filename
        let l:statusline .= '%* '.a:fname.' '
        " Left/right separator
        let l:statusline .= '%='
        " Flags (sort method included)
        let l:statusline .= '[' . ((a:sort ==# 'Name') ? 'N' : 'O') . ',' . join(a:flags, ',') . '] '
    else
        " 'TagBar' label
        let l:statusline .= ' TagBar > '
        " Filename
        let l:statusline .= a:fname
    endif
    return l:statusline
endfunction

function! dyamon#statusline#tabline() abort
    let line = ''
    for i in range(tabpagenr('$'))
        " Select the relevant highlight group
        if i + 1 == tabpagenr()
            let line .= '%#TabLineSel#'
        else
            let line .= '%#TabLine#'
        endif
        " Start tabpage label (with number indicator)
        let line .= '%' . (i + 1) . 'T ' . (i + 1)
        " Modified buffer indicator
        let l:modified = ''
        let l:buflist = tabpagebuflist(i + 1)
        for l:buf in l:buflist
            if getbufvar(l:buf, '&modified')
                let l:modified = '+'
            endif
        endfor
        let line .= l:modified
        " Get tabpage label
        let line .= ' %{dyamon#statusline#tablabel(' . (i + 1) . ')} '
        " Get number of windows
        "let line .= '[%{tabpagewinnr(' . (i + 1) . ', "$")}]'
    endfor
    " Fill with TabLineFill and reset tabpage label
    let line .= '%#TabLineFill#%T'
    return line
endfunction

function! dyamon#statusline#tablabel(tab) abort
    let buflist = tabpagebuflist(a:tab)
    let winnr = tabpagewinnr(a:tab)
    let cwd = getcwd(-1, a:tab)
    if exists('*FugitiveGitDir') && len(FugitiveGitDir(buflist[winnr-1]))
        let gitroot = fnamemodify(FugitiveGitDir(buflist[winnr-1]), ':h:h')
        let cwd = substitute(cwd, gitroot . '/', '', '')
    else
        let cwd = fnamemodify(cwd, ':t')
    endif
    return cwd
endfunction