function  [sys, x0, str, ts]  = eyesampl(t,x,u,flag,...
    timeRange, boundary, storeLength, eyeLine, scatterLine, sampleTime)
% EYESAMPL Simulink eye diagram and scatter plot --- sampled time version.
%   [SYS, X0, STR, TS]  = EYESAMPL(T,X,U,FLAG,TIMERANGE,BOUNDARY,STORELENGTH,EYELINE,SCATTERLINE,SAMPLETIME)
%
%   This M-file is designed to be used in a Simulink S-function block.
%   It plots eyediagram against time and the scatter plot.
%   The parameter for the block of this figure are:
%
%   timeRange    Time range = [Digit Sample Time, Plot offset, Decision offset]
%   boundary     Lower and upper boundary of the Y axis.
%   storeLength  Keep number of traces in storage for print purpose.
%   eyeLine      Line type for eye-pattern diagram (0 for no such plot)
%   scatterLine  Symbol type for scatter plot (0 for no such plot)
%   sampleTime   [Update sample time, update offset]
%   
%   This file takes scalar input or 2 dimensional vector input
%
%   Set this M-file up in an S-function block.
%   Set the function parameter up as a four element vector
%   which defines the axis of the graph. The line type must be in
%   quotes.
%
%   See also PLOT, SFUNYST, SFUNXY, EYEDIASI

%       Copyright 1996-2001 The MathWorks, Inc.
%       $Revision: 1.27 $ $Date: 2001/04/05 04:38:01 $ 

switch flag,

  %%%%%%%%%%%%%%%%%%
  % Initialization %
  %%%%%%%%%%%%%%%%%%
  case 0,
  [sys,x0,ts] = mdlInitializeSizes(...
      timeRange, boundary, storeLength, eyeLine, scatterLine, sampleTime);
  SetBlockCallbacks(gcbh);
  
  %%%%%%%%%%
  % Update %
  %%%%%%%%%%
  case 2,
  sys = mdlUpdate(t,x,u,...
      timeRange, boundary, storeLength, eyeLine, scatterLine, sampleTime);
  
  %%%%%%%%%%%%%%%%%%%
  % Next Sample Hit %
  %%%%%%%%%%%%%%%%%%%
  case 4,
  sys = mdlGetTimeOfNextVarHit(t, x, u);  
  
  %%%%%%%%%%%%%%%%%%%
  % Unhandled flags %
  %%%%%%%%%%%%%%%%%%%
  case {1, 3, 9 }
    sys=[];

  %%%%%%%%%
  % Start %
  %%%%%%%%%
  case 'Start'
  LocalBlockStartFcn

  %%%%%%%%
  % Stop %
  %%%%%%%%
  case 'Stop'
  LocalBlockStopFcn

  %%%%%%%%%%%%%%
  % NameChange %
  %%%%%%%%%%%%%%
  case 'NameChange'
  LocalBlockNameChangeFcn
    
  %%%%%%%%%%%%%
  % Load,Copy %
  %%%%%%%%%%%%%
  case { 'LoadBlock', 'CopyBlock' }
  LocalBlockLoadCopyFcn
    
  %%%%%%%%%%%%%%%
  % DeleteBlock %
  %%%%%%%%%%%%%%%
  case 'DeleteBlock'
  LocalBlockDeleteFcn
    
  %%%%%%%%%%%%%%%%
  % DeleteFigure %
  %%%%%%%%%%%%%%%%
  case 'DeleteFigure'
  LocalFigureDeleteFcn

  %%%%%%%%%%%%%%%%%%%%
  % Unexpected flags %
  %%%%%%%%%%%%%%%%%%%%
  otherwise
  if ischar(flag),
    errmsg=sprintf('Unhandled flag: '' 	%s''', flag);
  else
    errmsg=sprintf('Unhandled flag: 	%d', flag);
  end
  
  error(errmsg);
  
end

% end eyesampl

%
%=============================================================================
% mdlInitializeSizes
% Return the sizes, initial conditions, and sample times for the S-function.
%=============================================================================
%
function [sys,x0,ts] = mdlInitializeSizes(...
	timeRange, boundary, storeLength, eyeLine, scatterLine, sampleTime);

%
% call simsizes for a sizes structure, fill it in and convert it to a sizes array.
%
sizes = simsizes;

sizes.NumContStates  = 0;
sizes.NumDiscStates  = 3;   % 3 discrete states
sizes.NumOutputs     = 0;
sizes.NumInputs      = -1;  % dynamically sized input vector
sizes.DirFeedthrough = 0;   % the meter does not have direct feedthrough
sizes.NumSampleTimes = 1;

sys = simsizes(sizes);

%
% initialize the initial condition
%
x0 = [0, 0, 0]; 			% figure handle, u[last] input, last_mod_time

% x(1), the figure handle.
if isempty(sampleTime)
  sampleTime = [-1 0];
end;
if length(sampleTime) < 2
  sampleTime(2) = 0;
end
ts = [sampleTime(1), sampleTime(2)];

%
% str is always an empty matrix
%
str = [];

% end mdlInitializeSizes

%
%============================================================================
% mdlGetTimeOfNextVarHit
% Return the time of the next hit for this block. Note that the result 
% is absolute time.
%============================================================================
%
function sys = mdlGetTimeOfNextVarHit(t, x, u);  

if sampleTime(1) > 0
  sys = t + sampleTime(1);
else
  sys = [];
end;

% end mdlGetTimeOfNextVarHit

%
%=============================================================================
% mdlUpdate
% Handle discrete state updates, sample time hits, and major time step
% requirements.
%=============================================================================
%
function sys = mdlUpdate(t,x,u,...
   timeRange, boundary, storeLength, eyeLine, scatterLine, sampleTime);

%
% Locate the figure window associated with this block. If it's not a valid
% handle (it may have been closed by the user), then return.
%
figureHandle = GetEyesamplFigure(gcbh);
if ~ishandle(figureHandle)
  return;
end;  

threshold = .2;
eye_plot = ~((eyeLine(1)==0) + (eyeLine(1)=='0'));
scatter_plot = ~((scatterLine(1)==0) + (scatterLine(1) == '0'));
len_u = length(u);

if scatter_plot & (len_u > 2)
  sl_name = get_param(0,'CurrentSystem'); 
  block = get_param(sl_name ,'CurrentBlock'); 
  error(['Please set scatter plot line type to be zero in block ', sl_name, '/', block]);
  if len_u > 2
    error('The input signal length should be no larger than two.')
  end;
end;

plot_type = eye_plot + scatter_plot;
% in case of no plot
if plot_type <= 0
  return;
end;

if length(timeRange) < 2
  timeRange(2) = 0;
else
  timeRange(2) = rem(rem(timeRange(2), timeRange(1)) + timeRange(1), timeRange(1));
end;

if length(timeRange) < 3
  timeRange(3) = timeRange(1)/2 + timeRange(2);
end;

% initialize the figure
if x(1) == 0
  h_fig = x(1);
  % Initialize graph
  sl_name = gcs;
  block = get_param(sl_name,'CurrentBlock'); 
  sl_name_gcs = sl_name;
  if ~isempty(find(sl_name=='/'))
    sl_name = sl_name(find(sl_name=='/')+1 : length(sl_name));
  end;    

  [n_b, m_b]= size(block);
  if n_b < 1
    error('Cannot delete block while simulating');
  elseif n_b > 1
    error('Something wrong in get_param, You don''t have the current Simulink')
  end;
  
  %  if new_figure | old_figure
  %  generate a new figure here.
  x(1) = figureHandle;
  if plot_type == 1
    %open a single window figure
    delete(allchild(x(1)));
    figurePosition = get(x(1),'Position');
    figurePosition(3) = 360;	
    set(x(1), ...
	'Visible','on',...
	'Position', figurePosition );	  
    plt(1) = axes('Unit','norm',...
	'Pos',[.08, .08 .87,.87],...
	'Clipping', 'on',...
	'Parent', x(1),...
	'NextPlot','Add' ,...
	'HandleVisibility', 'off');
  elseif plot_type == 2
    % open a double window figure
    delete(allchild(x(1)));
    figurePosition = get(x(1),'Position');
    figurePosition(3) = 660;	
    set(x(1), ...
	'Visible','on',...
	'Position', figurePosition );	  
    plt(1) = axes('Unit','norm',...
	'Pos',[.08, .08 .8/2,.87],...
	'Clipping', 'on',...
	'Parent', x(1),...
	'NextPlot','Add',...
	'HandleVisibility', 'Off');
    plt(2) = axes('Unit','norm',...
	'Pos',[.08+.5, .08 .8/2,.87],...
	'Parent', x(1),...
	'NextPlot','Add',...
	'HandleVisibility', 'Off');
  end;
  
  i = 1;
  if eye_plot
    eye_plot = plt(i);
    i = i+1;
    set(x(1),'CurrentAxes',eye_plot);
    ax = [];
    lines = eyeLine;
    for j = 1:len_u+1;
      [col, lines] = strtok(lines, '/');
      if length(col) <= 1
	col = 'k-';
      end;
      if lower(col(1)) == 'n'
	ax(j) = 0
      else
	[linest, markst] = LineTypeSeparation(col(2:length(col)));
	ax(j) = plot(0,0,col,...    
	    'Erasemode','none',...
	    'Color',col(1),...
	    'LineStyle',linest,...
	    'Marker', markst,...
	    'Parent', eye_plot);
	set(ax(j), 'XData', [], 'YData', []);
      end;
    end;
    
    set(eye_plot,...
	'Xlim',[rem(timeRange(2)/timeRange(1),1)...
	    *timeRange(1), timeRange(1)+timeRange(2)], ...
	'Ylim',[boundary(1), boundary(2)], 'Clipping', 'on');
    set(eye_plot,'UserData',[ax, 0  ]);
    %                        |   | |==>space for time points
    %                        |   |==> number of NaN added
    %                        |===> have size of length(u)
  end;
  if (scatter_plot)
    scatter_plot = plt(i);
    i = i + 1;
    set(x(1),'CurrentAxes',scatter_plot);
    ax = [];
    lines = scatterLine;
    for j = 1:len_u
      [col, lines] = strtok(lines, '/');
      if length(col) <= 1
	col = 'k-';
      end;
      if ((len_u == 2) & (j == 2))
	ax(j) = 0;
      else
	if lower(col(1)) == 'n'
	  ax(j) = 0
	else
	  [linest, markst] = LineTypeSeparation(col(2:length(col)));
	  ax(j) = plot(0,0,col,...
	      'Erasemode','none',...
	      'Color',col(1),...
	      'LineStyle',linest,...
	      'Marker', markst,...
	      'Parent', scatter_plot);
	  if col(2) == '.'
	    set(ax(j), 'MarkerSize', 10);
	  end;
	  set(ax(j), 'XData', [], 'YData', []);
	end;
      end;
    end;
    if len_u == 2
      set(scatter_plot,...
	  'Xlim',[boundary(1), boundary(2)], ...
	  'Ylim',[boundary(1), boundary(2)]);
    else
      set(scatter_plot,...
	  'Xlim',[-1, 1],...
	  'Ylim',[boundary(1), boundary(2)]);
    end;
    set(scatter_plot,'UserData',[ax, abs(scatterLine)]);
  end;
  set(x(1),'UserData',[eye_plot, scatter_plot, timeRange, boundary, abs(eyeLine)]);
  %                    1         2             3           6         8
  set_param(sl_name_gcs, 'userdata', x(1));
  %  end;
elseif x(1) < 0
  % figure has been closed.
  return;
end;

plot_flag_test = allchild(0);
if isempty(plot_flag_test)
  return;
elseif isempty(find(plot_flag_test == x(1)))
  x(1) = -1;
  return;
end;

handles = get(x(1), 'UserData');
len_u = length(u);
changed_boundary   = 0;
if max(boundary ~= handles(6:7)) > 0
  changed_boundary = 1;
end;

mod_time = rem((t - timeRange(2))/timeRange(1), 1) * timeRange(1) + timeRange(2);
triggered = 0;
if (mod_time >= timeRange(3)) & (x(2) < timeRange(3))
  triggered = 1;
end;
x(2) = mod_time;

if handles(1) & eye_plot
  %eye_pattern plot
  sub_han = get(handles(1),'UserData');
  changed_timeRange = 0;
  if max(timeRange ~= handles(3:5)) > 0
    changed_timeRange = 1;
  end;
  if changed_boundary
    set(handles(1), 'Ylim', boundary);
  end;
  if changed_timeRange
    %this is a complicated process. Deal it later.
  end;
  len_h_userdata = length(handles);
  changed_line_type = 0;
  if (length(eyeLine) ~= len_h_userdata-7)
    changed_line_type = 1;
  elseif max(abs(eyeLine) ~= handles(8:len_h_userdata))
    changed_line_type = 1;
  else
    changed_line_type = 0;
  end;
  if changed_line_type
    lines = eyeLine;
    for i = 1 : len_u+1
      [col, lines] = strtok(lines, '/');
      if length(col) <= 1
	col = 'k-';
      end;
      if sub_han(i)
	[linest, markst] = LineTypeSeparation(col(2:length(col)));
	set(sub_han(i), ...
	    'Color',col(1),...
	    'LineStyle',linest,...
	    'Marker', markst);
      end;
    end;
    set(x(1),'UserData',[handles(1:7), abs(eyeLine)]);
  end;