" cecutil.vim : save/restore window position
"               save/restore mark position
"               save/restore selected user maps
"  Author:	Charles E. Campbell
"  Version:	18k	ASTRO-ONLY
"  Date:	Nov 22, 2017
"
"  Saving Restoring Destroying Marks: {{{1
"       call SaveMark(markname)       let savemark= SaveMark(markname)
"       call RestoreMark(markname)    call RestoreMark(savemark)
"       call DestroyMark(markname)
"       commands: SM RM DM
"
"  Saving Restoring Destroying Window Position: {{{1
"       call SaveWinPosn()        let winposn= SaveWinPosn()
"       call RestoreWinPosn()     call RestoreWinPosn(winposn)
"		\swp : save current window/buffer's position
"		\rwp : restore current window/buffer's previous position
"       commands: SWP RWP
"
"  Saving And Restoring User Maps: {{{1
"       call SaveUserMaps(mapmode,maplead,mapchx,suffix)
"       call RestoreUserMaps(suffix)
"
" GetLatestVimScripts: 1066 1 :AutoInstall: cecutil.vim
"
" You believe that God is one. You do well. The demons also {{{1
" believe, and shudder. But do you want to know, vain man, that
" faith apart from works is dead?  (James 2:19,20 WEB)
"redraw!|call inputsave()|call input("Press <cr> to continue")|call inputrestore()

" ---------------------------------------------------------------------
" Load Once: {{{1
if &cp || exists("g:loaded_cecutil")
 finish
endif
let g:loaded_cecutil = "v18k"
let s:keepcpo        = &cpo
set cpo&vim
"if exists("g:loaded_Decho")  " Decho
" DechoRemOn
"endif  " Decho

" =======================
"  Public Interface: {{{1
" =======================

" ---------------------------------------------------------------------
"  Map Interface: {{{2
if !hasmapto('<Plug>SaveWinPosn')
 map <unique> <Leader>swp <Plug>SaveWinPosn
endif
if !hasmapto('<Plug>RestoreWinPosn')
 map <unique> <Leader>rwp <Plug>RestoreWinPosn
endif
nmap <silent> <Plug>SaveWinPosn		:call SaveWinPosn()<CR>
nmap <silent> <Plug>RestoreWinPosn	:call RestoreWinPosn()<CR>

" ---------------------------------------------------------------------
" Command Interface: {{{2
com! -bar -nargs=0 SWP	call SaveWinPosn()
com! -bar -nargs=? RWP	call RestoreWinPosn(<args>)
com! -bar -nargs=1 SM	call SaveMark(<q-args>)
com! -bar -nargs=1 RM	call RestoreMark(<q-args>)
com! -bar -nargs=1 DM	call DestroyMark(<q-args>)

com! -bar -nargs=1 WLR	call s:WinLineRestore(<q-args>)

if v:version < 630
 let s:modifier= "sil! "
else
 let s:modifier= "sil! keepj "
endif

" ===============
" Functions: {{{1
" ===============

" ---------------------------------------------------------------------
" SaveWinPosn: {{{2
"    let winposn= SaveWinPosn()  will save window position in winposn variable
"    call SaveWinPosn()          will save window position in b:cecutil_winposn{b:cecutil_iwinposn}
"    let winposn= SaveWinPosn(0) will *only* save window position in winposn variable (no stacking done)
fun! SaveWinPosn(...)
"  echomsg "Decho: SaveWinPosn() a:0=".a:0
  let savedposn= winsaveview()
  if a:0 == 0
   if !exists("b:cecutil_iwinposn")
    let b:cecutil_iwinposn= 1
   else
    let b:cecutil_iwinposn= b:cecutil_iwinposn + 1
   endif
"   echomsg "Decho: saving posn to SWP stack"
   let b:cecutil_winposn{b:cecutil_iwinposn}= savedposn
  endif
  return savedposn
""  echomsg "Decho: SaveWinPosn() a:0=".a:0
"  if line("$") == 1 && getline(1) == ""
""   echomsg "Decho: SaveWinPosn : empty buffer"
"   return ""
"  endif
"  let so_keep   = &l:so
"  let siso_keep = &siso
"  let ss_keep   = &l:ss
"  setlocal so=0 siso=0 ss=0

"  let swline = line(".")                           " save-window line in file
"  let swcol  = col(".")                            " save-window column in file
"  if swcol >= col("$")
"   let swcol= swcol + virtcol(".") - virtcol("$")  " adjust for virtual edit (cursor past end-of-line)
"  endif
"  let swwline   = winline() - 1                    " save-window window line
"  let swwcol    = virtcol(".") - wincol()          " save-window window column
"  let savedposn = ""
""  echomsg "Decho: sw[".swline.",".swcol."] sww[".swwline.",".swwcol."]"
"  let savedposn = "call GoWinbufnr(".winbufnr(0).")"
"  let savedposn = savedposn."|".s:modifier.swline
"  let savedposn = savedposn."|".s:modifier."norm! 0z\<cr>"
"  if swwline > 0
"   let savedposn= savedposn.":".s:modifier."call s:WinLineRestore(".(swwline+1).")\<cr>"
"  endif
"  if swwcol > 0
"   let savedposn= savedposn.":".s:modifier."norm! 0".swwcol."zl\<cr>"
"  endif
"  let savedposn = savedposn.":".s:modifier."call cursor(".swline.",".swcol.")\<cr>"

"  " save window position in
"  " b:cecutil_winposn_{iwinposn} (stack)
"  " only when SaveWinPosn() is used
"  if a:0 == 0
"   if !exists("b:cecutil_iwinposn")
"    let b:cecutil_iwinposn= 1
"   else
"    let b:cecutil_iwinposn= b:cecutil_iwinposn + 1
"   endif
""   echomsg "Decho: saving posn to SWP stack"
"   let b:cecutil_winposn{b:cecutil_iwinposn}= savedposn
"  endif

"  let &l:so = so_keep
"  let &siso = siso_keep
"  let &l:ss = ss_keep

""  if exists("b:cecutil_iwinposn")                                                                  " Decho
""   echomsg "Decho: b:cecutil_winpos{".b:cecutil_iwinposn."}[".b:cecutil_winposn{b:cecutil_iwinposn}."]"
""  else                                                                                             " Decho
""   echomsg "Decho: b:cecutil_iwinposn doesn't exist"
""  endif                                                                                            " Decho
""  echomsg "Decho: SaveWinPosn [".savedposn."]"
"  return savedposn
endfun

" ---------------------------------------------------------------------
" RestoreWinPosn: {{{2
"      call RestoreWinPosn()
"      call RestoreWinPosn(winposn)
fun! RestoreWinPosn(...)
  if line("$") == 1 && getline(1) == ""
   return ""
  endif
  if a:0 == 0 || type(a:1) != 4
   " use saved window position in b:cecutil_winposn{b:cecutil_iwinposn} if it exists
   if exists("b:cecutil_iwinposn") && exists("b:cecutil_winposn{b:cecutil_iwinposn}")
    try
	 call winrestview(b:cecutil_winposn{b:cecutil_iwinposn})
    catch /^Vim\%((\a\+)\)\=:E749/
     " ignore empty buffer error messages
    endtry
    " normally drop top-of-stack by one
    " but while new top-of-stack doesn't exist
    " drop top-of-stack index by one again
    if b:cecutil_iwinposn >= 1
     unlet b:cecutil_winposn{b:cecutil_iwinposn}
     let b:cecutil_iwinposn= b:cecutil_iwinposn - 1
     while b:cecutil_iwinposn >= 1 && !exists("b:cecutil_winposn{b:cecutil_iwinposn}")
      let b:cecutil_iwinposn= b:cecutil_iwinposn - 1
     endwhile
     if b:cecutil_iwinposn < 1
      unlet b:cecutil_iwinposn
     endif
    endif
   else
    echohl WarningMsg
    echomsg "***warning*** need to SaveWinPosn first!"
    echohl None
   endif

  else	 " handle input argument
"   echomsg "Decho: using input a:1<".a:1.">"
   " use window position passed to this function
   call winrestview(a:1)
   " remove a:1 pattern from b:cecutil_winposn{b:cecutil_iwinposn} stack
   if exists("b:cecutil_iwinposn")
    let jwinposn= b:cecutil_iwinposn
    while jwinposn >= 1                     " search for a:1 in iwinposn..1
     if exists("b:cecutil_winposn{jwinposn}")    " if it exists
      if a:1 == b:cecutil_winposn{jwinposn}      " and the pattern matches
       unlet b:cecutil_winposn{jwinposn}            " unlet it
       if jwinposn == b:cecutil_iwinposn            " if at top-of-stack
        let b:cecutil_iwinposn= b:cecutil_iwinposn - 1      " drop stacktop by one
       endif
      endif
     endif
     let jwinposn= jwinposn - 1
    endwhile
   endif
  endif

""  echomsg "Decho: RestoreWinPosn() a:0=".a:0
""  echomsg "Decho: getline(1)<".getline(1).">"
""  echomsg "Decho: line(.)=".line(".")
"  if line("$") == 1 && getline(1) == ""
""   echomsg "Decho: RestoreWinPosn : empty buffer"
"   return ""
"  endif
"  let so_keep   = &l:so
"  let siso_keep = &l:siso
"  let ss_keep   = &l:ss
"  setlocal so=0 siso=0 ss=0

"  if a:0 == 0 || a:1 == ""
"   " use saved window position in b:cecutil_winposn{b:cecutil_iwinposn} if it exists
"   if exists("b:cecutil_iwinposn") && exists("b:cecutil_winposn{b:cecutil_iwinposn}")
""    echomsg "Decho: using stack b:cecutil_winposn{".b:cecutil_iwinposn."}<".b:cecutil_winposn{b:cecutil_iwinposn}.">"
"    try
"     exe s:modifier.b:cecutil_winposn{b:cecutil_iwinposn}
"    catch /^Vim\%((\a\+)\)\=:E749/
"     " ignore empty buffer error messages
"    endtry
"    " normally drop top-of-stack by one
"    " but while new top-of-stack doesn't exist
"    " drop top-of-stack index by one again
"    if b:cecutil_iwinposn >= 1
"     unlet b:cecutil_winposn{b:cecutil_iwinposn}
"     let b:cecutil_iwinposn= b:cecutil_iwinposn - 1
"     while b:cecutil_iwinposn >= 1 && !exists("b:cecutil_winposn{b:cecutil_iwinposn}")
"      let b:cecutil_iwinposn= b:cecutil_iwinposn - 1
"     endwhile
"     if b:cecutil_iwinposn < 1
"      unlet b:cecutil_iwinposn
"     endif
"    endif
"   else
"    echohl WarningMsg
"    echomsg "***warning*** need to SaveWinPosn first!"
"    echohl None
"   endif

"  else	 " handle input argument
""   echomsg "Decho: using input a:1<".a:1.">"
"   " use window position passed to this function
"   exe a:1
"   " remove a:1 pattern from b:cecutil_winposn{b:cecutil_iwinposn} stack
"   if exists("b:cecutil_iwinposn")
"    let jwinposn= b:cecutil_iwinposn
"    while jwinposn >= 1                     " search for a:1 in iwinposn..1
"     if exists("b:cecutil_winposn{jwinposn}")    " if it exists
"      if a:1 == b:cecutil_winposn{jwinposn}      " and the pattern matches
"       unlet b:cecutil_winposn{jwinposn}            " unlet it
"       if jwinposn == b:cecutil_iwinposn            " if at top-of-stack
"        let b:cecutil_iwinposn= b:cecutil_iwinposn - 1      " drop stacktop by one
"       endif
"      endif
"     endif
"     let jwinposn= jwinposn - 1
"    endwhile
"   endif
"  endif

"  " Seems to be something odd: vertical motions after RWP
"  " cause jump to first column.  The following fixes that.
"  " Note: was using wincol()>1, but with signs, a cursor
"  " at column 1 yields wincol()==3.  Beeping ensued.
"  let vekeep= &ve
"  set ve=all
"  if virtcol('.') > 1
"   exe s:modifier."norm! hl"
"  elseif virtcol(".") < virtcol("$")
"   exe s:modifier."norm! lh"
"  endif
"  let &ve= vekeep

"  let &l:so   = so_keep
"  let &l:siso = siso_keep
"  let &l:ss   = ss_keep

""  echomsg "Decho: RestoreWinPosn"
endfun

" ---------------------------------------------------------------------
" s:WinLineRestore: {{{2
fun! s:WinLineRestore(swwline)
"  echomsg "Decho: s:WinLineRestore(swwline=".a:swwline.")"
  while winline() < a:swwline
   let curwinline= winline()
   exe s:modifier."norm! \<c-y>"
   if curwinline == winline()
	break
   endif
  endwhile
"  echomsg "Decho: s:WinLineRestore"
endfun

" ---------------------------------------------------------------------
" GoWinbufnr: go to window holding given buffer (by number) {{{2
"   Prefers current window; if its buffer number doesn't match,
"   then will try from topleft to bottom right
fun! GoWinbufnr(bufnum)
"  call Dfunc("GoWinbufnr(".a:bufnum.")")
  if winbufnr(0) == a:bufnum
"   call Dret("GoWinbufnr : winbufnr(0)==a:bufnum")
   return
  endif
  winc t
  let first=1
  while winbufnr(0) != a:bufnum && (first || winnr() != 1)
  	winc w
	let first= 0
   endwhile
"  call Dret("GoWinbufnr")
endfun

" ---------------------------------------------------------------------
" SaveMark: sets up a string saving a mark position. {{{2
"           For example, SaveMark("a")
"           Also sets up a global variable, g:savemark_{markname}
fun! SaveMark(markname)
"  call Dfunc("SaveMark(markname<".string(a:markname).">)")
  let markname= a:markname
  if strpart(markname,0,1) !~ '\a'
   let markname= strpart(markname,1,1)
  endif
"  call Decho("markname=".string(markname))

  let lzkeep  = &lz
  set lz

  if 1 <= line("'".markname) && line("'".markname) <= line("$")
   let winposn               = SaveWinPosn(0)
   exe s:modifier."norm! `".markname
   let savemark              = SaveWinPosn(0)
   let g:savemark_{markname} = savemark
   let savemark              = markname.string(savemark)
   call RestoreWinPosn(winposn)
  else
   let g:savemark_{markname} = ""
   let savemark              = ""
  endif

  let &lz= lzkeep

"  call Dret("SaveMark : savemark<".savemark.">")
  return savemark
endfun

" ---------------------------------------------------------------------
" RestoreMark: {{{2
"   call RestoreMark("a")  -or- call RestoreMark(savemark)
fun! RestoreMark(markname)
"  call Dfunc("RestoreMark(markname<".a:markname.">)")

  if strlen(a:markname) <= 0
"   call Dret("RestoreMark : no such mark")
   return
  endif
  let markname= strpart(a:markname,0,1)
  if markname !~ '\a'
   " handles 'a -> a styles
   let markname= strpart(a:markname,1,1)
  endif
"  call Decho("markname=".markname." strlen(a:markname)=".strlen(a:markname))

  let lzkeep  = &lz
  set lz
  let winposn = SaveWinPosn(0)

  if strlen(a:markname) <= 2
   if exists("g:savemark_{markname}")
	" use global variable g:savemark_{markname}
"	call Decho("use savemark list")
	call RestoreWinPosn(g:savemark_{markname})
	exe "norm! m".markname
   endif
  else
   " markname is a savemark command (string)
"	call Decho("use savemark command")
   let markcmd= strpart(a:markname,1)
  call RestoreWinPosn(winposn)
   exe "norm! m".markname
  endif

  call RestoreWinPosn(winposn)
  let &lz       = lzkeep

"  call Dret("RestoreMark")
endfun

" ---------------------------------------------------------------------
" DestroyMark: {{{2
"   call DestroyMark("a")  -- destroys mark
fun! DestroyMark(markname)
"  call Dfunc("DestroyMark(markname<".a:markname.">)")

  " save options and set to standard values
  let reportkeep= &report
  let lzkeep    = &lz
  set lz report=10000

  let markname= strpart(a:markname,0,1)
  if markname !~ '\a'
   " handles 'a -> a styles
   let markname= strpart(a:markname,1,1)
  endif
"  call Decho("markname=".markname)

  let curmod  = &mod
  let winposn = SaveWinPosn(0)
  1
  let lineone = getline(".")
  exe "k".markname
  d
  put! =lineone
  let &mod    = curmod
  call RestoreWinPosn(winposn)

  " restore options to user settings
  let &report = reportkeep
  let &lz     = lzkeep

"  call Dret("DestroyMark")
endfun

" ---------------------------------------------------------------------
" QArgSplitter: to avoid \ processing by <f-args>, <q-args> is needed. {{{2
" However, <q-args> doesn't split at all, so this one returns a list
" with splits at all whitespace (only!), plus a leading length-of-list.
" The resulting list:  qarglist[0] corresponds to a:0
"                      qarglist[i] corresponds to a:{i}
fun! QArgSplitter(qarg)
"  call Dfunc("QArgSplitter(qarg<".a:qarg.">)")
  let qarglist    = split(a:qarg)
  let qarglistlen = len(qarglist)
  let qarglist    = insert(qarglist,qarglistlen)
"  call Dret("QArgSplitter ".string(qarglist))
  return qarglist
endfun

" ---------------------------------------------------------------------
" ListWinPosn: {{{2
"fun! ListWinPosn()                                                        " Decho 
"  if !exists("b:cecutil_iwinposn") || b:cecutil_iwinposn == 0             " Decho 
"   call Decho("nothing on SWP stack")                                     " Decho
"  else                                                                    " Decho
"   let jwinposn= b:cecutil_iwinposn                                       " Decho 
"   while jwinposn >= 1                                                    " Decho 
"    if exists("b:cecutil_winposn{jwinposn}")                              " Decho 
"     call Decho("winposn{".jwinposn."}<".b:cecutil_winposn{jwinposn}.">") " Decho 
"    else                                                                  " Decho 
"     call Decho("winposn{".jwinposn."} -- doesn't exist")                 " Decho 
"    endif                                                                 " Decho 
"    let jwinposn= jwinposn - 1                                            " Decho 
"   endwhile                                                               " Decho 
"  endif                                                                   " Decho
"endfun                                                                    " Decho 
"com! -nargs=0 LWP	call ListWinPosn()                                    " Decho 

" ---------------------------------------------------------------------
" SaveUserMaps: this function sets up a script-variable (s:restoremap) {{{2
"          which can be used to restore user maps later with
"          call RestoreUserMaps()
"
"          mapmode - see :help maparg for details (n v o i c l "")
"                    ex. "n" = Normal
"                    The letters "b" and "u" are optional prefixes;
"                    The "u" means that the map will also be unmapped
"                    The "b" means that the map has a <buffer> qualifier
"                    ex. "un"  = Normal + unmapping
"                    ex. "bn"  = Normal + <buffer>
"                    ex. "bun" = Normal + <buffer> + unmapping
"                    ex. "ubn" = Normal + <buffer> + unmapping
"          maplead - see mapchx
"          mapchx  - "<something>" handled as a single map item.
"                    ex. "<left>"
"                  - "string" a string of single letters which are actually
"                    multiple two-letter maps (using the maplead:
"                    maplead . each_character_in_string)
"                    ex. maplead="\" and mapchx="abc" saves user mappings for
"                        \a, \b, and \c
"                    Of course, if maplead is "", then for mapchx="abc",
"                    mappings for a, b, and c are saved.
"                  - :something  handled as a single map item, w/o the ":"
"                    ex.  mapchx= ":abc" will save a mapping for "abc"
"          suffix  - a string unique to your plugin
"                    ex.  suffix= "DrawIt"
fun! SaveUserMaps(mapmode,maplead,mapchx,suffix)
"  call Dfunc("SaveUserMaps(mapmode<".a:mapmode."> maplead<".a:maplead."> mapchx<".a:mapchx."> suffix<".a:suffix.">)")

  if !exists("s:restoremap_{a:suffix}")
   " initialize restoremap_suffix to null string
   let s:restoremap_{a:suffix}= ""
  endif

  " set up dounmap: if 1, then save and unmap  (a:mapmode leads with a "u")
  "                 if 0, save only
  let mapmode  = a:mapmode
  let dounmap  = 0
  let dobuffer = ""
  while mapmode =~# '^[bu]'
   if     mapmode =~# '^u'
    let dounmap = 1
    let mapmode = strpart(a:mapmode,1)
   elseif mapmode =~# '^b'
    let dobuffer = "<buffer> "
    let mapmode  = strpart(a:mapmode,1)
   endif
  endwhile
"  call Decho("dounmap=".dounmap."  dobuffer<".dobuffer.">")
 
  " save single map :...something...
  if strpart(a:mapchx,0,1) == ':'
"   call Decho("save single map :...something...")
   let amap= strpart(a:mapchx,1)
   if amap == "|" || amap == "\<c-v>"
    let amap= "\<c-v>".amap
   endif
   let amap                    = a:maplead.amap
   let s:restoremap_{a:suffix} = s:restoremap_{a:suffix}."|:sil! ".mapmode."unmap ".dobuffer.amap
   if maparg(amap,mapmode) != ""
    let maprhs                  = substitute(maparg(amap,mapmode),'|','<bar>','ge')
	let s:restoremap_{a:suffix} = s:restoremap_{a:suffix}."|:".mapmode."map ".dobuffer.amap." ".maprhs
   endif
   if dounmap
	exe "sil! ".mapmode."unmap ".dobuffer.amap
   endif
 
  " save single map <something>
  elseif strpart(a:mapchx,0,1) == '<'
"   call Decho("save single map <something>")
   let amap       = a:mapchx
   if amap == "|" || amap == "\<c-v>"
    let amap= "\<c-v>".amap
"	call Decho("amap[[".amap."]]")
   endif
   let s:restoremap_{a:suffix} = s:restoremap_{a:suffix}."|sil! ".mapmode."unmap ".dobuffer.amap
   if maparg(a:mapchx,mapmode) != ""
    let maprhs                  = substitute(maparg(amap,mapmode),'|','<bar>','ge')
	let s:restoremap_{a:suffix} = s:restoremap_{a:suffix}."|".mapmode."map ".dobuffer.amap." ".maprhs
   endif
   if dounmap
	exe "sil! ".mapmode."unmap ".dobuffer.amap
   endif
 
  " save multiple maps
  else
"   call Decho("save multiple maps")
   let i= 1
   while i <= strlen(a:mapchx)
    let amap= a:maplead.strpart(a:mapchx,i-1,1)
	if amap == "|" || amap == "\<c-v>"
	 let amap= "\<c-v>".amap
	endif
	let s:restoremap_{a:suffix} = s:restoremap_{a:suffix}."|sil! ".mapmode."unmap ".dobuffer.amap
    if maparg(amap,mapmode) != ""
     let maprhs                  = substitute(maparg(amap,mapmode),'|','<bar>','ge')
	 let s:restoremap_{a:suffix} = s:restoremap_{a:suffix}."|".mapmode."map ".dobuffer.amap." ".maprhs
    endif
	if dounmap
	 exe "sil! ".mapmode."unmap ".dobuffer.amap
	endif
    let i= i + 1
   endwhile
  endif
"  call Dret("SaveUserMaps : s:restoremap_".a:suffix.": ".s:restoremap_{a:suffix})
endfun

" ---------------------------------------------------------------------
" RestoreUserMaps: {{{2
"   Used to restore user maps saved by SaveUserMaps()
fun! RestoreUserMaps(suffix)
"  call Dfunc("RestoreUserMaps(suffix<".a:suffix.">)")
  if exists("s:restoremap_{a:suffix}")
   let s:restoremap_{a:suffix}= substitute(s:restoremap_{a:suffix},'|\s*$','','e')
   if s:restoremap_{a:suffix} != ""
"   	call Decho("exe ".s:restoremap_{a:suffix})
    exe "sil! ".s:restoremap_{a:suffix}
   endif
   unlet s:restoremap_{a:suffix}
  endif
"  call Dret("RestoreUserMaps")
endfun

" ==============
"  Restore: {{{1
" ==============
let &cpo= s:keepcpo
unlet s:keepcpo

" ================
"  Modelines: {{{1
" ================
" vim: ts=4 fdm=marker