From 4249328a06849f3c7fc932119b45f9e0d0d3408d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Karl=20Yngve=20Lerv=C3=A5g?= <karl.yngve+git@gmail.com>
Date: Tue, 11 Oct 2016 22:56:50 +0200
Subject: [PATCH] Fixed #592: Better handling of delimiter indentation

---
 autoload/vimtex/delim.vim | 16 ++-----
 indent/tex.vim            | 93 ++++++++++++++++++++++++++++++---------
 2 files changed, 76 insertions(+), 33 deletions(-)

diff --git a/autoload/vimtex/delim.vim b/autoload/vimtex/delim.vim
index a4104fe..6d680db 100644
--- a/autoload/vimtex/delim.vim
+++ b/autoload/vimtex/delim.vim
@@ -213,19 +213,9 @@ endfunction
 
 " }}}1
 
-function! vimtex#delim#get_valid_regexps(...) " {{{1
-  "
-  " Arguments: (Optional)
-  "   line number
-  "   column number
-  "
-  " Returns:
-  "   [regexp_open_delims, regexp_close_delims]
-  "
-
-  return call('vimtex#util#in_mathzone', a:000)
-        \ ? [s:re.delim_math.open, s:re.delim_math.close]
-        \ : [s:re.delim_tex.open,  s:re.delim_tex.close]
+function! vimtex#delim#get_delim_regexes(...) " {{{1
+  return [s:re.delim_math.open, s:re.delim_math.close,
+       \  s:re.delim_tex.open,  s:re.delim_tex.close]
 endfunction
 
 " }}}1
diff --git a/indent/tex.vim b/indent/tex.vim
index ae0af7a..116373f 100644
--- a/indent/tex.vim
+++ b/indent/tex.vim
@@ -46,11 +46,11 @@ function! VimtexIndent(lnum) " {{{1
 
   let l:nprev = s:get_prev_line(l:nprev, 'ignore-ampersands')
   if l:nprev == 0 | return 0 | endif
-  let l:prev = getline(l:nprev)
+  let l:prev = substitute(getline(l:nprev), '\\\@<!%.*', '', '')
 
   let l:ind = indent(l:nprev)
   let l:ind += s:indent_envs(l:cur, l:prev)
-  let l:ind += s:indent_delims(l:cur, l:prev, a:lnum)
+  let l:ind += s:indent_delims(l:cur, a:lnum, l:prev, l:nprev)
   let l:ind += s:indent_tikz(l:nprev, l:prev)
   return l:ind
 endfunction
@@ -104,12 +104,79 @@ let s:envs_begitem = s:envs_item . '\|' . s:envs_beglist
 let s:envs_enditem = s:envs_item . '\|' . s:envs_endlist
 
 " }}}1
-function! s:indent_delims(cur, prev, lnum) " {{{1
-  let [l:open, l:close] = vimtex#delim#get_valid_regexps(a:lnum, col('.'))
-  return &sw*(  max([s:count(a:prev, l:open) - s:count(a:prev, l:close), 0])
-        \     - max([s:count(a:cur, l:close) - s:count(a:cur, l:open),   0]))
+function! s:indent_delims(cur, ncur, prev, nprev) " {{{1
+  let [l:n1, l:dummy, l:m1] = s:split(a:prev, a:nprev)
+  let [l:n2, l:m2, l:dummy] = s:split(a:cur, a:ncur)
+
+  return &sw*(  max([s:count(l:n1, s:to) + s:count(l:m1, s:mo)
+        \          - s:count(l:n1, s:tc) - s:count(l:m1, s:mc), 0])
+        \     - max([s:count(l:n2, s:tc) + s:count(l:m2, s:mc)
+        \          - s:count(l:n2, s:to) - s:count(l:m2, s:mo), 0]))
 endfunction
 
+let [s:mo, s:mc, s:to, s:tc] = vimtex#delim#get_delim_regexes()
+
+function! s:count(line, pattern) " {{{2
+  let sum = 0
+  let indx = match(a:line, a:pattern)
+  while indx >= 0
+    let sum += 1
+    let match = matchstr(a:line, a:pattern, indx)
+    let indx += len(match)
+    let indx = match(a:line, a:pattern, indx)
+  endwhile
+  return sum
+endfunction
+
+" }}}2
+function! s:split(line, lnum) " {{{2
+  let l:map = map(range(1,col([a:lnum, strlen(a:line)])),
+        \ '[v:val, vimtex#util#in_mathzone(a:lnum, v:val)]')
+
+  " Adjust math mode limits (currently handle only $'s)
+  let l:prev = 1
+  for l:i in range(len(l:map))
+    if l:map[l:i][1] == 1 && l:prev == 0
+      let l:prev = l:map[l:i][1]
+      let l:map[l:i][1] = 0
+    else
+      let l:prev = l:map[l:i][1]
+    endif
+  endfor
+  if l:map[0][1] == 1 && a:line[0] ==# '$'
+    let l:map[0][1] = 0
+  endif
+
+  " Extract normal text
+  let l:normal = ''
+  for [l:i, l:val] in l:map
+    if l:val == 0
+      let l:normal .= a:line[l:i - 1]
+    endif
+  endfor
+  let l:normal = substitute(l:normal, '\\verb\(.\).\{}\1', '', 'g')
+
+  " Extract math text from beginning of line
+  let l:math_pre = ''
+  let l:indx = 0
+  while l:map[l:indx][1] == 1
+    let l:math_pre .= a:line[l:map[l:indx][0] - 1]
+    let l:indx += 1
+  endwhile
+
+  " Extract math text from end of line
+  let l:math_end = ''
+  let l:indx = -1
+  while l:map[l:indx][1] == 1
+    let l:math_end = a:line[l:map[l:indx][0] - 1] . l:math_end
+    let l:indx -= 1
+  endwhile
+
+  return [l:normal, l:math_pre, l:math_end]
+endfunction
+
+" }}}2
+
 " }}}1
 function! s:indent_tikz(lnum, prev) " {{{1
   if vimtex#env#is_inside('tikzpicture')
@@ -142,20 +209,6 @@ let s:tikz_commands = '\v\\%(' . join([
 
 " }}}1
 
-function! s:count(line, pattern) " {{{1
-  let sum = 0
-  let indx = match(a:line, a:pattern)
-  while indx >= 0
-    let sum += 1
-    let match = matchstr(a:line, a:pattern, indx)
-    let indx += len(match)
-    let indx = match(a:line, a:pattern, indx)
-  endwhile
-  return sum
-endfunction
-
-" }}}1
-
 let &cpo = s:cpo_save
 unlet s:cpo_save