From cd2954216a912e56167a897c91e6cca0e4f92903 Mon Sep 17 00:00:00 2001
From: "martin f. krafft" <madduck@madduck.net>
Date: Wed, 19 Dec 2018 12:41:31 +0100
Subject: [PATCH] editor config depending on mail area detection

---
 .vim/after/ftplugin/mail.vim | 78 ++++++++++++++++++++++++++++++++++++
 1 file changed, 78 insertions(+)

diff --git a/.vim/after/ftplugin/mail.vim b/.vim/after/ftplugin/mail.vim
index 6b6d527..21e66d8 100644
--- a/.vim/after/ftplugin/mail.vim
+++ b/.vim/after/ftplugin/mail.vim
@@ -3,3 +3,81 @@ setlocal formatoptions-=o
 setlocal formatoptions-=r
 
 "setlocal spell
+
+" Dynamically set format options, depending on where you are in a
+" mail, idea from Teemu Likonen:
+" http://groups.google.com/group/vim_use/msg/f59e5c1adc6be2b3
+
+let d_fo = &fo
+let s:defaults = 'setlocal tw=68 ts=2 sts=2 sw=2 fo='.d_fo
+execute s:defaults
+let b:MailAreaDetect=1
+
+"nnoremap <buffer> <LocalLeader>ma1 :call <SID>MailAreaDetect_On()
+"    \ <bar> echo 'MailAreaDetect On'<CR>
+"nnoremap <buffer> <LocalLeader>ma0 :call <SID>MailAreaDetect_Off()
+"    \ <bar> echo 'MailAreaDetect Off'<CR>
+
+nnoremap <buffer><silent> <F9> :call <SID>MailAreaDetect_Switch(0)<CR>
+inoremap <buffer><silent> <F9> <C-\><C-O>:call <SID>MailAreaDetect_Switch(1)<CR>
+
+function! s:MailAreaDetect_Switch(vmode)
+    if b:MailAreaDetect
+	silent call <SID>MailAreaDetect_Off()
+        let b:MailAreaDetect=0
+	echo 'MailAreaDetect Off'
+        if a:vmode
+            sleep 1
+        endif
+    else
+	silent call <SID>MailAreaDetect_On()
+        let b:MailAreaDetect=1
+	echo 'MailAreaDetect On'
+        if a:vmode
+            sleep 1
+        endif
+    endif
+endfu
+
+
+function! s:MailAreaDetect_On()
+    silent autocmd! MailAreaDetect CursorMoved,CursorMoved
+        \ <buffer> call <SID>AreaOptions()
+    let b:MailAreaDetect=1
+endfunction
+
+function! s:MailAreaDetect_Off()
+    silent autocmd! MailAreaDetect
+    execute s:defaults
+    let b:MailAreaDetect=0
+endfunction
+
+augroup MailAreaDetect
+    autocmd!
+    call <SID>MailAreaDetect_On()
+augroup END
+
+function! s:AreaOptions()
+    execute s:defaults
+    if <SID>CheckArea('\v^From( |: ).*\n','\v^$')
+        "echo 'Header'
+        setlocal fo-=a fo-=w fo-=t sts=0 sw=2 noet
+    elseif getline('.') =~ '\m^\s*>'
+        "echo 'Quotation'
+        setlocal fo-=a fo-=w
+    elseif <SID>CheckArea('\m^--- .*\n^+++ ','\v(^$|\n^-- $)')
+        "echo 'Patch'
+        setlocal fo-=a fo-=w fo-=t sts=0 sw=2 noet
+    elseif <SID>CheckArea('^-- $','^$')
+        "echo 'Signature'
+        setlocal fo-=a fo-=w fo-=t sts=0 sw=2 noet
+    else
+        "echo 'My text'
+        setlocal fo+=aw et
+    endif
+endfunction
+
+function! s:CheckArea(start, end)
+    return (search(a:start,'bcnW')-line('.')) >
+        \ (search(a:end,'bnW')-line('.'))
+endfunction
-- 
2.39.2