function dtfgui(mode)
%DTFGUI Graphical User Interface program for DT transfer functions


% ADSP Toolbox: Version 2.0 
% For use with "Analog and Digital Signal Processing", 2nd Ed.
% Published by PWS Publishing Co.
%
% Ashok Ambardar, EE Dept. MTU, Houghton, MI 49931, USA
% http://www.ee.mtu/faculty/akambard.html
% e-mail: akambard@mtu.edu
% Copyright (c) 1998



%v=matverch;
%if v<5,
%errordlg('This gui requires MATLAB 5.x and above','Version Error');
%return,
%end


if nargin == 0, mode = 0; end

if mode ~= 0,
   f = gcf;
   ui = get(f,'userdata');
   num_edt = ui(3);
   mag_axs=ui(27);
   phs_axs=ui(10);
   pz_axs=ui(23);
   sig_axs=ui(7);
   curs_btn = ui(21);
   curs_dsp = ui(17:20);
end

if mode == 0,
   grey = [0.5,0.5,0.5];
   ltgrey = grey*1.5;
   dkgrey = grey*0.5;
   offwhite = grey*1.9;
   scrn_size = get(0,'screensize');
   fig_w = 620; fig_h = 440+16;
   flft = (scrn_size(3) - fig_w)/2;
   fbtm = (scrn_size(4) - fig_h)/2;


%   ver_str = version;
ver4=0;   %ver4    = length(findstr('4.',ver_str));
   if ver4,
      int_str = 'yes';
      f = figure('pos',[flft,fbtm,fig_w,fig_h],'menubar','none',...
            'name','DT Transfer Functions','numbertitle','off',...
            'resize','off','vis','off','interruptible',int_str,...
            'color',dkgrey,'defaultaxesfontsize',10,...
            'defaulttextfontsize',10);
   else
      int_str = 'on';
      eval('f = colordef(''new'',''none'');');
      set(f,'pos',[flft,fbtm,fig_w,fig_h],'menubar','none',...
           'name','DT Transfer Functions','numbertitle','off',...
           'resize','off','vis','off','interruptible',int_str,...
           'color',dkgrey,'defaultaxesfontsize',8,...
           'defaultuicontrolback',[0.5,0.5,0.5],...
           'defaulttextfontsize',8);
   end


%%% OPTIONS: 
   uim(1) = uimenu('label','OPTIONS');
   uim(2) = uimenu(uim(1),'label','Help and Info','callback','dtfhlp');
   uim(3) = uimenu(uim(1),'label','Export Data','separator','on',...
                          'callback','dtfgui(15)');
   uim(4) = uimenu(uim(1),'label','Print Figure','separator','on',...
                          'callback','printdlg(gcf)');
   uim(5) = uimenu(uim(1),'label','Close and Exit','separator','on',...
                          'callback','close(gcf)');
   uim(6) = uimenu('label','   Axis Limits','separator','on',...
                          'callback','dtfgui(17)');
   uim(7) = uimenu('label','   Zoom ON','separator','on',...
                          'callback','dtfgui(18)');
   uim(8) = uimenu('label','   Zoom OFF','separator','on',...
                          'callback','dtfgui(19)');
   uim(9) = uimenu('label','   RESIZE','callback','dtfgui(20)');


%%%%%%%%


   lft = 10; btm = fig_h - 5;
   ui(1) = uicontrol('style','frame','pos',[5,btm-142-24+100-30,175,65+30],...
           'back',grey,'fore',ltgrey);

   btm = btm - 22;
   uix = uicontrol('style','text','pos',[lft,btm,165,17],...
           'string','Transfer Function H(z)','horiz','left','fore','c');
   btm = btm - 20;

   ui(2) = uicontrol('style','text','pos',[lft,btm,30,17],...
           'string','Num','horiz','left');
   ui(3) = uicontrol('style','edit','pos',[lft+35,btm,130,18],...
           'back','w','string','1 0');
   btm=btm - 20;
   ui(4) = uicontrol('style','text','pos',[lft,btm,30,17],...
           'string','Den','horiz','left');
   ui(5) = uicontrol('style','edit','pos',[lft+35,btm,130,18],...
           'back','w','string','1 -0.5','userdata',0);

   btm=btm - 28;
   ui(6) = uicontrol('style','push','pos',[lft+20,btm,60,20],...
           'string','Accept','callback','dtfplt');

   ui(9) = uicontrol('style','push','pos',[lft+85,btm,60,20],...
           'string','Reset','callback','dtfgui(1)');

   uit = uicontrol('style','frame','pos',[5,btm-200+138-20+22,175,72-22],...
           'back',grey,'fore',ltgrey);

   btm = btm - 35;
   ui(13) = uicontrol('style','text','pos',[lft,btm,65,17],...
           'string','Freq Axis','fore','c','horiz','left');

   ui(14) = uicontrol('style','popup','pos',[lft+70,btm,95,20],...
           'string','F|Omega','back','w',...
           'callback','dtfplt');

   btm = btm - 22;
   ui(15) = uicontrol('style','text','pos',[lft,btm,65,17],...
           'string','Freq Lims','fore','c','horiz','left');


   ui(16) = uicontrol('style','edit','pos',[lft+70,btm,95,20],...
           'string','0,0.5','back','w',...
           'callback','dtfplt');

   uit1 = uicontrol('style','frame','pos',[5,btm-200+138-20+22,175,72-22],...
           'back',grey,'fore',ltgrey);

   btm = btm - 35;
   ui(46) = uicontrol('style','text','pos',[lft,btm,60,17],...
           'string','Time domain','fore','c');

   ui(47) = uicontrol('style','popup','pos',[lft+61,btm,105,20],...
           'string',['Impulse response|Step response'],'back','w',...
           'callback','dtfplt');

   btm = btm - 22;
   ui(45) = uicontrol('style','text','pos',[lft,btm,65,17],...
           'string','DT Index','fore','c','horiz','left');

   ui(44) = uicontrol('style','edit','pos',[lft+70,btm,95,20],...
           'string','0, 20','back','w',...
           'callback','dtfplt');

  ui(30) = uicontrol('style','frame','pos',[5,btm-105+18,175,95-18],...
           'back',grey,'fore',ltgrey);

   btm = btm -30;
   ui(31) = uicontrol('style','text','pos',[lft,btm,165,17],...
           'string','MULTIPLE ZEROS','fore','c','horiz','left');

   btm = btm - 18;
   ui(32) = uicontrol('style','text','pos',[lft,btm,165,17],...
           'back','w','horiz','left');

   btm = btm - 18;
   ui(33) = uicontrol('style','text','pos',[lft,btm,165,17],...
           'back','w','horiz','left');

   btm = btm - 18;
   ui(34) = uicontrol('style','text','pos',[lft,btm,165,17],...
           'back','w','horiz','left');

  ui(37) = uicontrol('style','frame','pos',[5,btm-105+18,175,95-18],...
           'back',grey,'fore',ltgrey);

   btm = btm -30;
   ui(38) = uicontrol('style','text','pos',[lft,btm,165,17],...
           'string','MULTIPLE POLES','fore','c','horiz','left');

   btm = btm - 18;
   ui(39) = uicontrol('style','text','pos',[lft,btm,165,17],...
           'back','w','horiz','left');

   btm = btm - 18;
   ui(40) = uicontrol('style','text','pos',[lft,btm,165,17],...
           'back','w','horiz','left');

   btm = btm - 18;
   ui(41) = uicontrol('style','text','pos',[lft,btm,165,17],...
           'back','w','horiz','left');

   btm = btm -40;
   ui(21) = uicontrol('style','check','pos',[lft+100,btm,70,20],...
           'string','Cursor','back','y','callback','dtfgui(7)');

   ui(61) = uicontrol('style','text','pos',[5,1,610,17],'horiz','left',...
           'userdata',0,'fore','b','back',offwhite);


   pos = get(f,'pos');
   lef = pos(3)-166;
   bot = pos(4)-21;

   ui(17) = uicontrol('style','text','pos',[lef,bot,20,20],...
           'string','X ','horiz','right');
   ui(18) = uicontrol('style','text','pos',[lef+20,bot,60,20],...
           'string','','back','w');
   ui(19) = uicontrol('style','text','pos',[lef+85,bot,20,20],...
           'string','Y ','horiz','right');
   ui(20) = uicontrol('style','text','pos',[lef+105,bot,60,20],...
           'string','','back','w');

   set(ui(17:20),'vis','off');


   ui(7) = axes('units','pixel','pos',[220,35+16,160,160],'box','on',...
             'color','k',...
             'xgrid','on','ygrid','on');
  title('Impulse Response h[n]');
   xlabel('DT Index  [n]');
   ui(8) = line('xdata',0,'ydata',0,'color','m','erase','back');

%For drawing dt signals with markers
   if ver4,
      ui(12) = line('xdata',0,'ydata',0,'color','m','linestyle','o',...
                'erase','back');
   else
      ui(12) = line('xdata',0,'ydata',0,'color','m','linestyle','none',...
                    'marker','o','erase','back');
   end
   set(ui(7),'userdata',ui([8,12]));

   ui(10) = axes('units','pixel','pos',[430,35+16,160,160],'box','on',...
            'xlim',[-0.5,0.5],'color','k',...
             'xgrid','on','ygrid','on');
   title('Unwrapped Phase [deg]');
   xlabel('Digital Frequency  [F]');
   ui(11) = line('xdata',0,'ydata',0,'color','y','erase','back');
   set(ui(10),'userdata',ui(11));
   set(ui(3),'userdata',ui(10));


   ui(23) = axes('units','pixel','pos',[220,240+20,160,160],'box','on',...
            'color','k','xgrid','on','ygrid','on');
   title('Pole-Zero Plot');
   ui(26) = line('xdata',0,'ydata',0,'color','y','erase','back');
   if ver4,
      ui(24) = line('xdata',0,'ydata',0,'color','c','linestyle','o',...
                'erase','back');
   else
      ui(24) = line('xdata',0,'ydata',0,'color','c','linestyle','none',...
                    'marker','o','erase','back','markersize',8);
   end
   if ver4,
      ui(25) = line('xdata',0,'ydata',0,'color','g','linestyle','x',...
                'erase','back');
   else
      ui(25) = line('xdata',0,'ydata',0,'color','g','linestyle','none',...
                    'marker','x','erase','back','markersize',11);
   end
%   axis('equal');
   set(ui(23),'userdata',ui(24:26));

   ui(27) = axes('units','pixel','pos',[430,240+20,160,160],'box','on',...
            'xlim',[-0.5,0.5],'color','k',...
             'xgrid','on','ygrid','on');
   title('Magnitude Spectrum');
   xlabel('Digital Frequency  [F]');
   ui(28) = line('xdata',0,'ydata',0,'color','y','erase','back');
   set(ui(27),'userdata',ui(28));
%   set(ui(3),'userdata',ui(10));



   set(f,'userdata',ui);
   set(ui(1),'userdata',ui(10));
   dtfplt;
   drawnow;
   set(f,'vis','on');

elseif mode == 1, % clear
   set(ui(3),'string','1 0');
   set(ui(5),'string','1 -0.5');
   dtfplt;


elseif mode == 7, % cursor
    if get(curs_btn,'value')
    set(curs_dsp,'vis','on');

    set(f,'WindowButtonMotionFcn','dtfgui(8)');

    else

  set(f,'Pointer','arrow','WindowButtonMotionFcn','');


   set(curs_dsp,'vis','off')
   set(curs_btn,'value',0),

    end


elseif mode == 8, % cursor movement
       h=gca;
       set(f,'currentaxes',h);
       lim=get(h,'pos');  % get current axis position
       c_p = [lim(1) lim(1)+lim(3) lim(2) lim(2)+lim(4)];
       f_p=get(f,'CurrentPoint'); % get co-ordinates of current point

     if f_p(1) < c_p(1) | f_p(1) > c_p(2) | f_p(2) < c_p(3) | f_p(2) > c_p(4)
        set(f,'Pointer','arrow');

        set(curs_dsp(2),'string','');
        set(curs_dsp(4),'string','');

     else
        curr_pt=get(h,'CurrentPoint');  % get current mouse position
        set(f,'Pointer','crosshair');
        set(curs_dsp(2),'string',num2str(curr_pt(1,1)));
        set(curs_dsp(4),'string',num2str(curr_pt(1,2)));
     end


elseif mode == 15, %Export data
dtfplt;
fstr=get(ui(14),'string');fval=get(ui(14),'value');fstr=fstr(fval,:);
tstr=get(ui(47),'string');tval=get(ui(47),'value');tstr=tstr(tval,:);
str1='Export transfer function numerator as';
str2='Export transfer function denominator as';
str3=['Export ', tstr, ' (symbolic) as'];
str4=['Export frequency ', fstr, ' as'];
str5='Export magnitude as';
str6='Export phase (deg) as';
exp_str={str1,str2,str3,str4,str5,str6};
exp_var={'numdtf','dendtf','n_resp','freqdtf','Mdtf','Pdtf'};

expect=inputdlg(exp_str,'Save Variables as',1,exp_var);
if ~isempty(expect)
hn=get(ui(13),'userdata');%%% FIX FOR UIs 
hd=get(ui(14),'userdata');%%% FIX FOR UIs 
tres=get(ui(15),'userdata');
ftf=get(ui(16),'userdata');
mtf=get(ui(17),'userdata');
ptf=get(ui(18),'userdata');

if ~isempty(expect{1}),assignin('base',expect{1},hn);end
if ~isempty(expect{2}),assignin('base',expect{2},hd);end
if ~isempty(expect{3}),assignin('base',expect{3},tres);end
if ~isempty(expect{4}),assignin('base',expect{4},ftf);end
if ~isempty(expect{5}),assignin('base',expect{5},mtf);end
if ~isempty(expect{6}),assignin('base',expect{6},ptf);end
end


elseif mode == 16, % Axis Control Help
msgbox([' First click in a plot window.                             ',... 
'                  Then, come back and execute'],...
'Axis Control Info','help')


elseif mode == 17, % Axis Control
cur_axs=[];   cur_obj = gco;
   cur_par = get(cur_obj,'parent');
if ~isempty(cur_par)
   if cur_par == f,
      cur_axs = cur_obj;
   else
      cur_axs = cur_par;
   end
end

if isempty(cur_axs),dtfgui(16);
else
set(curs_btn,'value',0);
dtfgui(7); 
if any(cur_axs==ui([7,10,23,27]))
if cur_axs==ui(7),txt=get(ui(7),'userdata'); 
elseif cur_axs==ui(10),txt='Transfer Function Phase';
elseif cur_axs==ui(27),txt='Transfer Function Gain';
elseif cur_axs==ui(23),txt='Pole-Zero Plot';
end
axlimdlg(txt,[1 1]); %[1 1]=auto +linear/log,  [1 0]=auto, no linear/log
else
dtfgui(16);
end
end


elseif mode == 18, % zoom on
set(curs_btn,'value',0);
dtfgui(7);                    % Use CURSOR MODE 
if get(ui(5),'userdata')==0  %%Change ui(15) to whatever
zoom on
set(ui(5),'userdata',1);
else
msgbox('Zoom is already ON.','Zoom Info','help')
end

elseif mode == 19, % zoom off
set(curs_btn,'value',0);
dtfgui(7);                    % Use CURSOR MODE 
if get(ui(5),'userdata')==1

%%%%%Insert old zoom off here
set(f,'currentaxes',ui(7));
zoom out,zoom reset,zoom off
set(f,'currentaxes',ui(10));
zoom out,zoom reset,zoom off
set(f,'currentaxes',ui(23));
zoom out,zoom reset,zoom off
set(f,'currentaxes',ui(27));
zoom out,zoom reset,zoom off
set(ui(5),'userdata',0);
else
msgbox('Zoom is already OFF.','Zoom Info','help')
end



elseif mode == 20, % mouse functionality
cur_axs = [];   cur_obj = gco;
   cur_par = get(cur_obj,'parent');

if ~isempty(cur_par)
   if cur_par == f,
      cur_axs = cur_obj;
   else
      cur_axs = cur_par;
   end
end


if isempty(cur_axs),dtfgui(16);return,end

   if any(cur_axs == [mag_axs,phs_axs,pz_axs,sig_axs]),
      axes(cur_axs);
         axs_pos = get(cur_axs,'pos');
         if axs_pos(4) == 160, % need to maximize
            set(mag_axs,'pos',[-600 35+16 160 160]);
            set(phs_axs,'pos',[-600 35+16 160 160]);
            set(pz_axs,'pos',[-600 240+20 160 160]);
            set(sig_axs,'pos',[-600 240+20 160 160]);

            if cur_axs==pz_axs
            set(cur_axs,'pos',[210 35+16 375 375]);
            else
            set(cur_axs,'pos',[210 35+16 400 365]);
            end

         else % minimization
            set(mag_axs,'pos',[430 240+20 160 160]);
            set(phs_axs,'pos',[430 35+16 160 160]);
            set(pz_axs,'pos',[220 240+20 160 160]);
            set(sig_axs,'pos',[220 35+16 160 160]);

         end
   else
         dtfgui(16);
   end


end