Rework buffers provider

Close #8
Close #59

autoload/clap/icon.vim

@@ -162,6 +162,24 @@ function! clap#icon#get(pattern) abort
   endif
 endfunction
 
+function! s:get_or_default(k) abort
+  return get(g:clap#icon#extensions, a:k, g:clap#icon#default)
+endfunction
+
+function! clap#icon#for(bufname) abort
+  let ft = getbufvar(a:bufname, '&ft')
+  if empty(ft)
+    let ext = fnamemodify(expand(a:bufname), ':e')
+    if empty(ext)
+      return g:clap#icon#default
+    else
+      return s:get_or_default(ext)
+    endif
+  else
+    return s:get_or_default(ft)
+  return
+endfunction
+
 function! clap#icon#get_all() abort
   let extensions = values(g:clap#icon#extensions)
   let exact_matches = values(g:clap#icon#exact_matches)

autoload/clap/provider/buffers.vim

@@ -4,18 +4,47 @@
 let s:save_cpo = &cpo
 set cpo&vim
 
-" TODO more fancy buffers, e.g., append icon.
+function! s:padding(origin, target_width) abort
+  let width = strdisplaywidth(a:origin)
+  if width < a:target_width
+    return a:origin.repeat(' ', a:target_width - width)
+  else
+    return a:origin
+  endif
+endfunction
+
+function! s:format_buffer(b)
+  let name = bufname(a:b)
+  let name = empty(name) ? '[No Name]' : fnamemodify(name, ":p:~:.")
+  let flag = a:b == bufnr('')  ? '%' : (a:b == bufnr('#') ? '#' : ' ')
+  let modified = getbufvar(a:b, '&modified') ? ' [+]' : ''
+  let readonly = getbufvar(a:b, '&modifiable') ? '' : ' [RO]'
+
+  let bp = s:padding('['.a:b.']', 5)
+  let fsize = s:padding(clap#util#getfsize(name), 6)
+  let icon = s:padding(clap#icon#for(name), 3)
+  let extra = join(filter([modified, readonly], '!empty(v:val)'), '')
+  let line = get(s:line_info, a:b, '')
+
+  return trim(printf("%s %s %s  %s %s %s %s", bp, fsize, icon, flag, name, extra, line))
+endfunction
+
 function! s:buffers() abort
   redir => l:buffers
     silent buffers
   redir END
-  let s:buffers_cache = split(l:buffers, "\n")
-  return s:buffers_cache
+  let s:line_info = {}
+  for line in split(l:buffers, "\n")
+    let bufnr = str2nr(trim(matchstr(line, '^\s*\d\+')))
+    let lnum = matchstr(line, 'line.*$')
+    let s:line_info[bufnr] = lnum
+  endfor
+  return map(clap#util#buflisted_sorted(), "s:format_buffer(str2nr(v:val))")
 endfunction
 
 function! s:buffers_sink(selected) abort
-  call win_gotoid(bufwinid(g:clap.start.bufnr))
-  let b = split(a:selected)[0]
+  call g:clap.start.goto_win()
+  let b = matchstr(a:selected, '^\[\zs\d\+\ze\]')
   execute 'buffer' b
 endfunction
 

autoload/clap/util.vim

@@ -227,5 +227,22 @@ function! clap#util#expand(args) abort
   return a:args
 endfunction
 
+function! clap#util#getfsize(fname) abort
+  let l:size = getfsize(a:fname)
+  if l:size == 0 || l:size == -1 || l:size == -2
+    return ''
+  endif
+  if l:size < 1024
+    let size = l:size.'B'
+  elseif l:size < 1024*1024
+    let size = printf('%.1f', l:size/1024.0) . 'K'
+  elseif l:size < 1024*1024*1024
+    let size = printf('%.1f', l:size/1024.0/1024.0) . 'M'
+  else
+    let size = printf('%.1f', l:size/1024.0/1024.0/1024.0) . 'G'
+  endif
+  return size
+endfunction
+
 let &cpo = s:save_cpo
 unlet s:save_cpo