!-----------------------------------------------------------------
!
!  This file is (or was) part of SPLASH, a visualisation tool
!  for Smoothed Particle Hydrodynamics written by Daniel Price:
!
!  http://users.monash.edu.au/~dprice/splash
!
!  SPLASH comes with ABSOLUTELY NO WARRANTY.
!  This is free software; and you are welcome to redistribute
!  it under the terms of the GNU General Public License
!  (see LICENSE file for details) and the provision that
!  this notice remains intact. If you modify this file, please
!  note section 2a) of the GPLv2 states that:
!
!  a) You must cause the modified files to carry prominent notices
!     stating that you changed the files and the date of any change.
!
!  Copyright (C) 2005-2017 Daniel Price. All rights reserved.
!  Contact: daniel.price@monash.edu
!
!-----------------------------------------------------------------

!--------------------
!  SPLASH MAIN MENU
!--------------------
module mainmenu
 implicit none
 public :: menu,allowrendering,set_extracols

 private

contains

subroutine menu
 use filenames,        only:defaultsfile,limitsfile,unitsfile,fileprefix,set_filenames
 use labels,           only:label,labelvec,iamvec,isurfdens,itoomre,ipdf,icolpixmap,is_coord,ix
 use limits,           only:write_limits,lim2,lim,reset_lim2,lim2set
 use options_data,     only:submenu_data
 use settings_data,    only:ndim,numplot,ndataplots,nextra,ncalc,ivegotdata, &
                             buffer_data,ncolumns,icoords,icoordsnew,iRescale
 use settings_limits,  only:submenu_limits,iadapt
 use settings_part,    only:submenu_particleplots,mstari
 use settings_page,    only:submenu_page,submenu_legend,interactive,nacross,ndown
 use settings_render,  only:submenu_render,iplotcont_nomulti,icolours,double_rendering
 use settings_vecplot, only:submenu_vecplot,iplotpartvec
 use settings_xsecrot, only:submenu_xsecrotate,xsec_nomulti
 use settings_units,   only:write_unitsfile
 use multiplot
 use prompting,        only:prompt,print_logical
 use transforms,       only:transform_label
 use defaults,         only:defaults_write
 use getdata,          only:get_data
 use geomutils,        only:set_coordlabels
 use timestepping
 integer            :: i,icol,ihalf,iadjust,indexi,ierr
 integer            :: ipicky,ipickx,irender,ivecplot,icontourplot
 integer            :: iamvecprev, ivecplottemp,ichoose
 integer            :: maxdigits
 character(len=5)   :: ioption
 character(len=100) :: vecprompt,string
 character(len=20)  :: rprompt
 character(len=2)   :: fmtstrlen
 character(len=50)  :: fmtstr1,fmtstr2,fmtstr3
 character(len=*), parameter :: sep="(55('-'))"
 logical            :: iAllowRendering

 irender = 0
 icontourplot = 0
 ivecplot = 0
 if (ndim > 1 .and. ix(1) > 0) then
    ipickx = ix(1)
 else
    ipickx = 1
 endif
 ipicky = 1

 menuloop: do
!---------------------------------------------------------------------------
!  preliminaries
!---------------------------------------------------------------------------
!
!--make sure the number of columns is set appropriately
!  (nextra can change depending on what options are set)
!
    !
    !--numplot is the total number of data columns (read + calculated)
    !   not including the particle co-ordinates
    !  nextra are extra graphs to plot (e.g. convergence plots, power spectrum)
    !
    !  note that numplot and ndataplots should *only* be set here
    !  this means that even if ncolumns changes during data reads while plotting
    !  we don't start plotting new quantities
    !
    call set_extracols(ncolumns,ncalc,nextra,numplot,ndataplots)
!
!--set the coordinate and vector labels
!  if working in a different coordinate system
!
    call set_coordlabels(numplot)

!--set contents of the vector plotting prompt
    vecprompt(1:6) = '0=none'
    indexi = 7
    iamvecprev = 0
    do icol=1,numplot
       if (iamvec(icol) /= 0 .and. iamvec(icol) /= iamvecprev) then
          iamvecprev = iamvec(icol)
          if (iamvec(icol) >= 10) then
             write(vecprompt(indexi:),"(',',1x,i2,'=',a)") &
                 iamvec(icol),trim(labelvec(icol))
          else
             write(vecprompt(indexi:),"(',',1x,i1,'=',a)") &
                 iamvec(icol),trim(labelvec(icol))
          endif
          indexi = len_trim(vecprompt) + 1
       endif
    enddo

    ichoose = 0

!---------------------------------------------------------------------------
!  print menu
!---------------------------------------------------------------------------

    if (numplot > 0) then
!
!--data columns
!
       call print_header()
       print sep
       ihalf = numplot/2                ! print in two columns
       iadjust = mod(numplot,2)
       maxdigits = floor(log10(real(maxplot)))+1
       write(fmtstrlen,"(A1,I1)") "i",maxdigits
       fmtstr1 = "(1x,"//trim(adjustl(fmtstrlen))//",')',1x,a20,1x," &
                     //trim(adjustl(fmtstrlen))//",')',1x,a20)"
       print fmtstr1, &
          (i,transform_label(label(i),itrans(i)), &
          ihalf + i + iadjust, transform_label(label(ihalf + i + iadjust), &
          itrans(ihalf+i+iadjust)),i=1,ihalf)
       if (iadjust /= 0) then
          fmtstr2 = "(1x,"//trim(adjustl(fmtstrlen))//",')',1x,a20)"
          print fmtstr2, &
              ihalf + iadjust,transform_label(label(ihalf + iadjust), &
              itrans(ihalf+iadjust))
       endif
!
!--multiplot
!
       print sep
       fmtstr3 = "(1x,"//trim(adjustl(fmtstrlen))//",')',1x,a,'[ '," &
                     //trim(adjustl(fmtstrlen))//",' ]',5x,a2,') ',a)"
       print fmtstr3, &
           numplot+1,'multiplot ',nyplotmulti,'m','set multiplot '
    else
!
!--if no data
!
       maxdigits = 1
       print "(/a)",' No data: You may choose from the options below '
    endif
!
!--options
!
    print sep
    if (ndim <= 1) then
       print "(a)",' d(ata) p(age) o(pts) l(imits) le(g)end s,S(ave) q(uit)'
    else
       print "(a)",' d(ata) p(age) o(pts) l(imits) le(g)end h(elp)'
       print "(a)",' r(ender) v(ector) x(sec/rotate) s,S(ave) q(uit)'
    endif
    print sep

!
!--prompt user for selection
!
    write(*,"(a)",ADVANCE='NO') 'Please enter your selection now (y axis or option):'
    read(*,"(a)",iostat=ierr) string
    if (ierr < 0) stop 'reached end of input' ! end of input (e.g. in script)
    if (ierr > 0) stop !'error reading input'
    ioption = string(1:maxdigits)

!------------------------------------------------------------
!  if input is an integer and within range, plot data
!------------------------------------------------------------
    read(ioption,*,iostat=ierr) ipicky
    if (ierr /= 0) ipicky = -1

    !--try to read more integers from the string
    !  if present, use these to set up an "instant multiplot"
    if (ipicky > 0 .and. ipicky < numplot+1 .and. len_trim(string) > 2) then
       call set_instant_multiplot(string,ipicky,ipickx,numplot,nyplotmulti,&
                                multiplotx,multiploty,nacross,ndown)
    endif

    if (ipicky > 0 .and. ipicky <= numplot+1) then

       if (.not.ivegotdata) then
          !
          !--do not allow plotting if no data - instead try to read data
          !
          print*,' no data '
          if (buffer_data) then
             call get_data(-1,.false.)
          else
             call get_data(1,.false.,firsttime=.true.)
          endif
       else
          !
          !--if needed prompt for x axis selection
          !
          if (ipicky <= (numplot-nextra)) then
             if (ipickx==0) then
                if (ndim > 1 .and. ix(1) > 0) then
                   ipickx = ix(1)
                else
                   ipickx = 1 ! do not allow zero as default
                endif
             endif
             if (ipickx==ipicky) then ! do not allow x same as y by default
                if (ipickx > 1) then
                   ipickx = ipicky-1
                else
                   ipickx = ipicky+1
                endif
             endif
             call prompt(' (x axis) ',ipickx)
             !--go back to y prompt if out of range
             if (ipickx > numplot .or. ipickx <= 0) cycle menuloop
             !
             !--work out whether rendering is allowed
             !
             iAllowRendering = allowrendering(ipickx,ipicky,xsec_nomulti)
             !
             !--prompt for render and vector plots
             ! -> only allow if in "natural" coord system, otherwise h's would be wrong)
             ! (a future feature might be to interpolate in icoord then translate the pixels
             !  to icoordsnew, or alternatively plot non-cartesian pixel shapes)
             ! -> also do not allow if transformations are applied
             !
             if (is_coord(ipicky,ndim) .and. is_coord(ipickx,ndim)) then
                if (iAllowRendering) then
                   call prompt('(render) (0=none)',irender,0,(numplot-nextra))
                   if (irender > 0 .and. iplotcont_nomulti .and. icolours /= 0) then
                      if (double_rendering) then
                         rprompt = '2nd render'
                      else
                         rprompt = 'contours'
                      endif
                      call prompt('('//trim(rprompt)//') (0=none)',icontourplot,0,(numplot-nextra))
                      if (icontourplot==irender) then
                         if (iadapt) then
                            print "(a)",' limits for '//trim(rprompt)//' are adaptive'
                         else
                            if (.not.lim2set(icontourplot)) lim2(icontourplot,:) = lim(icontourplot,:)
                            call prompt(' enter min for '//trim(rprompt)//':',lim2(icontourplot,1))
                            call prompt(' enter max for '//trim(rprompt)//':',lim2(icontourplot,2))
                            if (all(abs(lim2(icontourplot,:)-lim(icontourplot,:)) < tiny(lim))) then
                               call reset_lim2(icontourplot)
                            endif
                         endif
                      endif
                   endif
                else
                   irender = 0
                endif
                if (any(iamvec(1:numplot) /= 0) .and. (icoordsnew==icoords)) then
                   ivecplottemp = -1
                   ierr = 1
                   do while(ierr /= 0 .and. ivecplottemp /= 0)
                      ivecplottemp = ivecplot
                      ierr = 0
                      call prompt('(vector plot) ('//trim(vecprompt)//')',ivecplottemp,0,maxval(iamvec))
                      if (.not.any(iamvec(1:numplot)==ivecplottemp)) then
                         print "(a)",'Error, value not in list'
                         ierr = 1
                      endif
                   enddo
                   ivecplot = ivecplottemp
                else
                   ivecplot = 0
                endif
                if (ivecplot > 0 .and. irender==0) then
                   call prompt('plot particles?',iplotpartvec)
                endif
             else
                if (iAllowRendering) then
                   call prompt('(render) (0=none)',irender,0,(numplot-nextra))
                else
                   irender = 0
                endif
                ivecplot = 0
             endif
          elseif (ipicky > 0 .and. ipicky==itoomre .or. ipicky==isurfdens) then
             if (ipicky==isurfdens) print "(a)",' setting x axis to r for surface density plot'
             if (ipicky==itoomre) print "(a)",' setting x axis to r for Toomre Q plot'
             call prompt('enter central mass for Toomre Q calculation [code units] ',mstari)
             ipickx = 1
             irender = 0
             ivecplot = 0
          elseif (ipicky > 0 .and. ipicky==ipdf) then
             call prompt(' enter x axis for PDF calculation ',ipickx,1,ndataplots)
             irender = 0
             ivecplot = 0
          elseif (ipicky > 0 .and. ipicky==icolpixmap) then
             call prompt(' enter corresponding SPH column for particle data ',irender,0,ndataplots)
             ipickx = 0
             ivecplot = 0
          elseif (ipicky==numplot+1) then
             !
             !--for multiplots, check that options are valid. If not, re-prompt for multiplot
             !  settings
             !
             ipickx   = 0
             irender  = 0
             ivecplot = 0
             if (any(multiploty(1:nyplotmulti) <= 0) .or. &
                any(multiploty(1:nyplotmulti) > numplot) .or. &
                any(multiplotx(1:nyplotmulti) <= 0) .or. &
                any(multiplotx(1:nyplotmulti) > numplot)) then
                print "(/,a,/)",'ERROR: multiplot settings out of range, please re-enter these'
                call options_multiplot
             endif
          endif
          !
          !--call main plotting routine
          !
          call timestep_loop(ipicky,ipickx,irender,icontourplot,ivecplot)
       endif
!------------------------------------------------------------------------
!  if input is an integer > numplot+1, quit
!------------------------------------------------------------------------
    elseif (ipicky > numplot+1) then
       return
    else
!------------------------------------------------------------------------
!  if input is a string, use menu options
!------------------------------------------------------------------------
!--  Menu shortcuts; so you can type e.g. o2 and get the o)ptions menu, item 2
       read(ioption(2:2),*,iostat=ierr) ichoose
       if (ierr /= 0) ichoose = 0

       select case(ioption(1:1))
!------------------------------------------------------------------------
!+ Sets up plotting of (m)ultiple quantities per timestep
       case('m','M')
          call options_multiplot
!------------------------------------------------------------------------
!+ This submenu sets options relating to the (d)ata read
       case('d','D')
          call submenu_data(ichoose)
!------------------------------------------------------------------------
!+ This option turns (i)nteractive mode on/off
       case('i','I')
          interactive = .not.interactive
          print "(a)",' Interactive mode is '//print_logical(interactive)
!------------------------------------------------------------------------
!+ This submenu sets (p)age setup options
       case('p','P')
          call submenu_page(ichoose)
!------------------------------------------------------------------------
!+ This submenu sets particle plot (o)ptions
       case('o','O')
          call submenu_particleplots(ichoose)
!------------------------------------------------------------------------
!+ This submenu sets le(g)end and title options
       case('g','G')
          call submenu_legend(ichoose)
!------------------------------------------------------------------------
!+ This submenu sets (r)endering options
       case('r','R')
          if (ndim <= 1) print "(a)",'WARNING: these options have no effect in < 2D'
          call submenu_render(ichoose)
!------------------------------------------------------------------------
!+ This submenu sets (v)ector plotting options
       case('v','V')
          if (ndim <= 1) print "(a)",'WARNING: these options have no effect in < 2D'
          call submenu_vecplot(ichoose)
!------------------------------------------------------------------------
!+ This submenu sets cross section and rotation options
       case('x','X')
          if (ndim <= 1) print "(a)",'WARNING: these options have no effect in < 2D'
          call submenu_xsecrotate(ichoose)
!------------------------------------------------------------------------
!+ This submenu sets options relating to the plot limits
       case('l','L')
          call submenu_limits(ichoose)
!------------------------------------------------------------------------
!+ The (s)ave option saves the default options to a
!+ file called `splash.defaults'' in the current directory which
!+ is read automatically upon the next invocation of splash.
!+ This file uses namelist formatting and may be edited
!+ manually prior to startup if so desired. This is quite
!+ useful for setting multiplots with many plots per page
!+ The (S)ave option writes both the defaults file and
!+ also saves the current plot limits to a file called
!+ 'splash.limits' which is also read automatically
!+ at startup.
       case('s')
          if (ioption(2:2)=='a') then
             call prompt('enter prefix for defaults file: ',fileprefix,noblank=.true.)
             if (index(fileprefix,'.defaults')==0) then
                defaultsfile = trim(fileprefix)//'.defaults'
             else
                defaultsfile = trim(fileprefix)
             endif
          endif
          call defaults_write(defaultsfile)
       case('S')
          if (ioption(2:2)=='a' .or. ioption(2:2)=='A') then
             call prompt('enter prefix for filenames: ',fileprefix,noblank=.true.)
             call set_filenames(trim(fileprefix))
          endif
          call defaults_write(defaultsfile)
          call write_limits(limitsfile)
          if (iRescale) call write_unitsfile(unitsfile,ncolumns)
!------------------------------------------------------------------------
!+ Slightly obsolete: prints whatever help may be helpful
       case('h','H')
          print "(10(/a))",' Hint: menu items can be shortcut by typing, e.g. o2 for ',&
                 ' the o)ptions menu, item 2.',' ', &
                 ' for detailed help, consult the user guide',' ',&
                 '  (splash/docs/splash.pdf ',&
                 '   or http://users.monash.edu.au/~dprice/splash/userguide/)', &
                 ' ',' and/or the online FAQ. If you''re really stuck, email me! '
          read*
!------------------------------------------------------------------------
!+ (q)uit, unsurprisingly, quits. Typing a number greater
!+ than the number of data columns also exits the program
!+ (e.g. I often simply type 99 to exit).
       case('q','Q')
          return
!------------------------------------------------------------------------
       case DEFAULT
          print "(a)",'unknown option '//trim(ioption)
       end select

    endif

 enddo menuloop

 return

contains

!----------------------------------------------------
! multiplot setup
!----------------------------------------------------
subroutine options_multiplot
 use settings_page,   only:nacross, ndown
 use settings_render, only:iplotcont_nomulti
 use limits,          only:lim,lim2,lim2set,reset_lim2
 use labels,          only:is_coord,labeltype
 use params,          only:maxparttypes
 use settings_data,   only:ntypes
 integer :: ifac,ierr,itype,nvalues
 logical :: isamex, isamey, icoordplot, anycoordplot, imultisamepanel
 integer, dimension(maxparttypes)   :: itypelist

 call prompt('Enter number of plots per timestep:',nyplotmulti,1,numplot)

 isamey = all(multiploty(1:nyplotmulti)==multiploty(1))
 if (ndim >= 2) call prompt('Same y axis for all?',isamey)
 if (isamey) then
    call prompt('Enter y axis for all plots',multiploty(1),1,numplot)
    multiploty(2:nyplotmulti) = multiploty(1)
 endif

 isamex = all(multiplotx(1:nyplotmulti)==multiplotx(1))
 call prompt('Same x axis for all?',isamex)
 if (isamex) then
    call prompt('Enter x axis for all plots',multiplotx(1),1,numplot)
    multiplotx(2:nyplotmulti) = multiplotx(1)
 endif

 anycoordplot = .false.
 do i=1,nyplotmulti
    print*,'-------------- Plot number ',i,' --------------'
    if (.not.isamey) then
       call prompt(' y axis ',multiploty(i),1,numplot)
    endif
    if (multiploty(i) <= ndataplots .and. .not.isamex) then
       call prompt(' x axis ',multiplotx(i),1,ndataplots)
    else
       if (multiploty(i)==isurfdens) then
          print "(a)",' setting x axis to r for surface density plot'
          multiplotx(i) = 1
       elseif (multiploty(i)==itoomre) then
          print "(a)",' setting x axis to r for Toomre Q plot'
          multiplotx(i) = 1
       elseif (multiploty(i)==ipdf) then
          call prompt(' enter x axis for PDF calculation ',multiplotx(i),1,ndataplots)
       elseif (multiploty(i)==icolpixmap) then
          call prompt(' enter corresponding SPH column for particle data ',irendermulti(i),0,ndataplots)
          multiplotx(i) = 1
       elseif (.not.isamex) then
          multiplotx(i) = multiploty(i)
       endif
    endif
    !
    !--work out whether rendering is allowed
    !
    iAllowRendering = allowrendering(multiplotx(i),multiploty(i))

    icoordplot = (is_coord(multiplotx(i),ndim) .and. is_coord(multiploty(i),ndim))
    if (icoordplot) anycoordplot = icoordplot

    if (icoordplot) then
       if (iAllowRendering) then
          call prompt('(render) (0=none)',irendermulti(i),0,numplot-nextra)
          if (irendermulti(i) > 0 .and. iplotcont_nomulti .and. icolours /= 0) then
             if (double_rendering) then
                rprompt = '2nd render'
             else
                rprompt = 'contours'
             endif
             call prompt('('//trim(rprompt)//') (0=none)',icontourmulti(i),0,numplot-nextra)
             if (icontourmulti(i)==irendermulti(i)) then
                if (iadapt) then
                   print "(a)",' limits for '//trim(rprompt)//' are adaptive '
                else
                   if (.not.lim2set(icontourmulti(i))) lim2(icontourmulti(i),:) = lim(icontourmulti(i),:)
                   call prompt(' enter min for '//trim(rprompt)//':',lim2(icontourmulti(i),1))
                   call prompt(' enter max for '//trim(rprompt)//':',lim2(icontourmulti(i),2))
                   if (all(abs(lim2(icontourmulti(i),:)-lim(icontourmulti(i),:)) < tiny(lim))) then
                      call reset_lim2(icontourmulti(i))
                   endif
                endif
             endif
          else
             icontourmulti(i) = 0
          endif
          !iplotcontmulti(i) = iplotcont_nomulti
       endif
       if (any(iamvec(1:numplot) > 0)) then
          ivecplottemp = -1
          ierr = 1
          do while(ierr /= 0 .and. ivecplottemp /= 0)
             ivecplottemp = ivecplotmulti(i)
             ierr = 0
             call prompt('(vector plot) ('//trim(vecprompt)//')',ivecplottemp,0,maxval(iamvec))
             if (.not.any(iamvec(1:numplot)==ivecplottemp)) then
                print "(a)",'Error, value not in list'
                ierr = 1
             endif
          enddo
          ivecplotmulti(i) = ivecplottemp
       else
          ivecplotmulti(i) = 0
       endif
       if (ivecplotmulti(i) > 0 .and. irendermulti(i)==0) then
          call prompt('plot particles?',iplotpartvec)
       endif
    else
       !
       !--set irender, icontour and ivecplot to zero if no rendering allowed
       !
       if (multiploty(i) /= icolpixmap) irendermulti(i) = 0
       icontourmulti(i) = 0
       ivecplotmulti(i) = 0
    endif

    if (icoordplot .and. ndim >= 2) then
       call prompt(' is this a cross section (no=projection)? ',x_secmulti(i))
       if (x_secmulti(i)) then
          call prompt('enter co-ordinate location of cross section slice',xsecposmulti(i))
       endif
    endif
    !
    !--prompt for selection of different particle types
    !  if more than one SPH particle type is present
    !
    itypelist = 0
    if (ntypes >= 2) then
       call prompt('use all active particle types?',iusealltypesmulti(i))

       if (iusealltypesmulti(i)) then
          nvalues = 0
          itypelist(:) = 0
       else
          !
          !--prepare list of types based on current iplotpartoftypemulti
          !
          nvalues = 0
          do itype=1,ntypes
             if (iplotpartoftypemulti(itype,i)) then
                nvalues = nvalues + 1
                itypelist(nvalues) = itype
             endif
          enddo
          if (nvalues==0) then
             print*,'warning: internal error in type list'
             itypelist(:) = 0
             nvalues = 1
          endif
          !
          !--prompt for list of types to use
          !
          do itype=1,ntypes
             print "(i2,':',1x,a)",itype,'use '//trim(labeltype(itype))//' particles'
          enddo

          call prompt('Enter type or list of types to use',itypelist,nvalues,1,ntypes)
          !
          !--set which particle types to plot
          !
          iplotpartoftypemulti(:,i) = .false.
          iplotpartoftypemulti(itypelist(1:nvalues),i) = .true.

       endif
    else
       !
       !--if ntypes < 2 always use the (only) particle type
       !
       iusealltypesmulti(i) = .true.
    endif
 enddo

 if (isamex .and. .not.anycoordplot) then
    imultisamepanel = .false.
    !call prompt('plot all plots in same panel? (default is different panels)',imultisamepanel)
 else
    imultisamepanel = .false.
 endif

 if (nyplotmulti==1 .or. imultisamepanel) then
    nacross = 1
    ndown = 1
    print*,'setting nacross,ndown = ',nacross,ndown
 elseif (mod(nacross*ndown,nyplotmulti) /= 0) then
    !--guess nacross,ndown based on largest factor
    ifac = nyplotmulti/2
    do while (mod(nyplotmulti,ifac) /= 0 .and. ifac > 1)
       ifac = ifac - 1
    enddo
    if (ifac <= 1) then
       nacross = nyplotmulti/2
    else
       nacross = ifac
    endif
    if (nacross <= 0) nacross = 1
    ndown = nyplotmulti/nacross
    print*,'setting nacross,ndown = ',nacross,ndown
 else
    print*,'nacross = ',nacross,' ndown = ',ndown
 endif

 return
end subroutine options_multiplot
end subroutine menu

!----------------------------------------------
! utility function which determines whether
! or not rendering is allowed or not
!----------------------------------------------
logical function allowrendering(iplotx,iploty,xsec)
 use labels,          only:ih,irho,get_z_coord
 use multiplot,       only:itrans
 use settings_data,   only:ndim,ndataplots,icoords,icoordsnew
 use settings_render, only:icolour_particles
 use geometry,        only:coord_is_length
 integer, intent(in) :: iplotx,iploty
 logical, intent(in), optional :: xsec
 integer :: itransx,itransy,iz
 logical :: is_xsec,islengthz

 if (present(xsec)) then
    is_xsec = xsec
 else
    is_xsec = .true.
 endif
 itransx = 0
 itransy = 0
 if (iplotx > 0) itransx = itrans(iplotx)
 if (iploty > 0) itransy = itrans(iploty)

 iz = get_z_coord(ndim,iplotx,iploty)
 islengthz = coord_is_length(iz,icoordsnew)
!
!--work out whether rendering is allowed based on presence of rho, h & m in data read
!  also must be in base coordinate system and no transformations applied
!
 if ((ih > 0 .and. ih <= ndataplots) &
    .and.(irho > 0 .and. irho <= ndataplots) &
    .and.(icoords==icoordsnew .or. (.not.is_xsec .or. (is_xsec .and. islengthz))) &
    .and.(itransx==0 .and. itransy==0)) then

    allowrendering = .true.
 else
    allowrendering = .false.
    if (icolour_particles) allowrendering = .true.
 endif

end function allowrendering

!----------------------------------------------
! utility function which sets up the "extra"
! plot columns and returns the total number
! of allowed columns for plotting
!----------------------------------------------
subroutine set_extracols(ncolumns,ncalc,nextra,numplot,ndataplots)
 use params,        only:maxplot
 use labels,        only:ipowerspec,iacplane,isurfdens,itoomre,iutherm,ipdf,label,icolpixmap
 use settings_data, only:ndim,icoordsnew,ivegotdata,debugmode
 use settings_part, only:iexact
 use system_utils,  only:lenvironment
 use write_pixmap,  only:ireadpixmap
 integer, intent(in)    :: ncolumns
 integer, intent(inout) :: ncalc
 integer, intent(out)   :: nextra,numplot,ndataplots

 !
 !-add extra columns (but not if nothing read from file)
 !
 if (ncolumns > 0) then
    nextra = 0
    ipowerspec = 0
    iacplane = 0
    isurfdens = 0
    itoomre = 0
    if (ndim==3 .and. icoordsnew==2 .or. icoordsnew==3) then
       nextra = nextra + 1
       isurfdens = ncolumns + ncalc + nextra
       label(isurfdens) = 'Surface density'
       if (iutherm > 0 .and. iutherm <= ncolumns) then
          nextra = nextra + 1
          itoomre = ncolumns + ncalc + nextra
          label(itoomre) = 'Toomre Q parameter'
       endif
    endif
    if (ndim==3 .and. lenvironment('SPLASH_TURB')) then  !--Probability Density Function
       nextra = nextra + 1
       ipdf = ncolumns + ncalc + nextra
       label(ipdf) = 'PDF'
    endif

    if (ndim <= 1 .and. lenvironment('SPLASH_TURB')) then !! .or. ndim==3) then ! if 1D or no coord data (then prompts for which x)
       nextra = nextra + 1      ! one extra plot = power spectrum
       ipowerspec = ncolumns + ncalc + nextra
       label(ipowerspec) = '1D power spectrum'
    else
       ipowerspec = 0
    endif
    if (iexact==6) then       ! toy star plot a-c plane
       nextra = nextra + 1
       iacplane = ncolumns + ncalc + nextra
       label(iacplane) = 'a-c plane'
    else
       iacplane = 0
    endif
    !nextra = nextra + 1
    !label(ncolumns+ncalc+nextra) = 'gwaves'
    if (ndim >= 2) then
       if (ireadpixmap) then
          nextra = nextra + 1
          icolpixmap = ncolumns + ncalc + nextra
          label(icolpixmap) = '2D pixel map'
       endif
    endif
 endif
!
!--now that we know nextra, set the total number of allowed plots (numplot).
!
 if (ivegotdata) then
    numplot = ncolumns + ncalc + nextra
    if (numplot > maxplot) then
       print "(a,i3,a)",' ERROR: total number of columns = ',numplot,' is greater '
       print "(a,i3,a)",'        than the current allowed maximum (',maxplot,').'
       print "(a)",'        This is set by the parameter "maxplot" in the params module'
       print "(a)",'        in the file globaldata.f90 -- edit this and recompile splash'
       print "(a)",'        (or email me if this happens to increase the default limit)'
       stop
    endif
    ndataplots = ncolumns + ncalc
 else
    numplot = 0
    ndataplots = 0
    ncalc = 0
 endif

 if (debugmode) print*,'DEBUG: numplot = ',numplot, ' ncalc = ',ncalc,' ndataplots = ',ndataplots

 return
end subroutine set_extracols

!----------------------------------------
! instant multiplot setup from main menu
!----------------------------------------
subroutine set_instant_multiplot(string,ipicky,ipickx,numplot,nmulti,multiplotx,multiploty,nx,ny)
 use params,    only:maxplot
 use prompting, only:prompt
 character(len=*), intent(in) :: string
 integer, intent(in) :: numplot
 integer, intent(inout) :: ipicky,ipickx
 integer, intent(inout) :: nmulti,nx,ny
 integer, intent(inout) :: multiplotx(:),multiploty(:)
 integer :: ipickarr(maxplot),ierr,i

 ipickarr = 0
 read(string,*,iostat=ierr) ipickarr
 i = 1
 do while (i < size(ipickarr) .and. ipickarr(i) /= 0 .and. ipickarr(i) <= numplot)
    i = i + 1
 enddo
 if (i > 2) then
    nmulti = i-1
    !--make sure nmulti matches the number of panels on the page
    if (nmulti /= nx*ny) then
       nx = 1
       ny = nmulti
    endif
    multiploty(1:nmulti) = ipickarr(1:nmulti)
    ipicky = numplot + 1
    if (ipickx==0) ipickx = 1 ! do not allow zero as default
    call prompt(' (x axis) ',ipickx)
    multiplotx(1:nmulti) = ipickx
 endif

end subroutine set_instant_multiplot

!--------------------
! print menu header
!--------------------
subroutine print_header
 integer :: v(8),i
 integer, parameter :: m(48) = (/32,68,111,110,39,116,32,102,111,114,103,101,116,32,116,111,&
                      32,115,101,110,100,32,68,97,110,105,101,108,32,97,32,98,&
                      105,114,116,104,100,97,121,32,109,101,115,115,97,103,101,33/)
 integer, parameter :: c(49) = (/32,120,111,120,111,120,111,120,111,32,77,101,114,114,121,32,&
                      67,104,114,105,115,116,109,97,115,32,102,114,111,109,32,115,&
                      112,108,97,115,104,33,32,120,111,120,111,120,111,120,111,120,111/)
 integer, parameter :: d(49) = (/32,79,111,79,111,79,111,79,32,83,80,76,65,83,72,32,119, &
                      105,115,104,101,115,32,121,111,117,32,97,32,118,101,114,121,32,104,&
                      97,112,112,121,32,33,32,79,111,79,111,79,111,79/)
 integer, parameter :: l(45) = (/64,130,64,216,222,220,206,64,232,210,218,202,64,194,&
                      206,222,64,210,220,64,194,64,206,194,216,194,240,242,64,204,194,&
                      228,88,64,204,194,228,64,194,238,194,242,92,92,92/)
 integer, parameter :: a(49) = (/32,83,101,103,109,101,110,116,97,116,105,111,110,32,&
                      102,97,117,108,116,46,32,80,108,101,97,115,101,32,114,101,98,111,&
                      111,116,32,121,111,117,114,32,99,111,109,112,117,116,101,114,46/)
 integer, parameter :: s(48)=(/64,138,228,228,222,228,116,64,230,224,216,194,230,208,64,&
                      200,210,202,200,92,64,160,216,202,194,230,202,64,228,202,196,222,&
                      222,232,64,242,222,234,228,64,198,222,218,224,234,232,202,228/)
 integer, parameter :: p(53)=(/12,7,10,13,10,14,18,11,15,14,12,14,17,18,16,18,12,11,12,&
                      17,13,15,11,15,13,12,12,17,12,11,16,18,14,9,11,17,17,13,10,18,16,10,15,&
                      18,12,18,18,12,16,14,10,9,14/)

 call date_and_time(values=v)
 if (v(2)==m(1)/4 .and. v(3)==v(2)-2) then
    print "(/,48(a))",(achar(m(i)),i=1,48)
 elseif (v(2)==(m(1)-20) .and. v(3)>20) then
    print "(/,49(a))",(achar(c(i)),i=1,49)
 elseif (v(2)==nint(0.6) .and. v(3)==d(2)/79) then
    print "(/,40(a),i4,9(a))",(achar(d(i)),i=1,40),v(1),(achar(d(i)),i=41,49)
 elseif (v(2)==l(1)-59 .and. v(3)==l(1)/4**2) then
    print "(/,45(a))",(achar(l(i)/2),i=1,45)
 elseif (v(2)==a(14)/8 .and. v(3)==int(1.3) .and. v(5) < (l(1)-16)/4) then
    print "(/,49(a))",(achar(a(i)),i=1,49)
 elseif (v(2)==(s(5)+78)/100+1 .and. v(3)==nint(sqrt(1.5)) .and. v(5) < s(1)/5.3) then
    print "(/,48(a))",(achar(s(i)/2),i=1,48)
 elseif ((v(2)==int(0.25*p(1)) .and. v(3)==p(6)) .or. (abs(v(3)/real(v(2))-4.*atan(1.)) < 1.3e-3)) then
    print "(/,1x,53(a))",(achar(p(i)+39),i=1,53)
 else
    print "(/a)",' You may choose from a delectable sample of plots'
 endif

end subroutine print_header

end module mainmenu
