function hDialogout=export2wsdlg(checkboxLabels, defaultVariableNames, itemsToExport, varargin)
%EXPORT2WSDLG Exports variables to the workspace. 
%   EXPORT2WSDLG(CHECKBOXLABELS, DEFAULTVARIABLENAMES, ITEMSTOEXPORT) creates
%   a dialog with a series of checkboxes and edit fields. CHECKBOXLABELS is a 
%   cell array of labels for the checkboxes. DEFAULTVARIABLENAMES is a cell
%   array of strings that serve as a basis for variable names that appear in 
%   the edit fields. ITEMSTOEXPORT is a cell array of the values to be stored 
%   in the variables. If there is only one item to export, EXPORT2WSDLG creates
%   a text control instead of a checkbox. 
%
%   EXPORT2WSDLG(CHECKBOXLABELS, DEFAULTVARIABLENAMES, ITEMSTOEXPORT, TITLE) 
%   creates the dialog with TITLE as its title.
%
%   EXPORT2WSDLG(CHECKBOXLABELS, DEFAULTVARIABLENAMES, ITEMSTOEXPORT, TITLE, 
%                   SELECTED) 
%   creates the dialog allowing the user to control which checkboxes are
%   checked. SELECTED is a logical array, whose length is the same as 
%   CHECKBOXLABELS. True indicates that the checkbox should initially be 
%   checked, false unchecked.
%
%   EXPORT2WSDLG(CHECKBOXLABELS, DEFAULTVARIABLENAMES, ITEMSTOEXPORT, TITLE, 
%                   SELECTED, HELPFUNCTION) 
%   creates the dialog with a help button. HELPFUNCTION is a callback that 
%   displays help.
%
%   EXPORT2WSDLG(CHECKBOXLABELS, DEFAULTVARIABLENAMES, ITEMSTOEXPORT, TITLE, 
%                   SELECTED, HELPFUNCTION, FUNCTIONLIST) 
%   creates a dialog that enables the user to pass in FUNCTIONLIST, a cell 
%   array of functions and optional arguments that calcluate, then return 
%   the value to export. FUNCTIONLIST should be the same length as CHECKBOXLABELS. 
%
%   User can edit the text fields to modify the default variable names. If the
%   same name appears in multiple edit fields, EXPORT2WSDLG creates a structure 
%   using that name. It then uses the DEFAULTVARIABLENAMES as fieldnames for 
%   that structure.
%
%   The lengths of CHECKBOXLABELS, DEFAULTVARIABLENAMES, ITEMSTOEXPORT and 
%   SELECTED must all be equal.
%
%   The strings in DEFAULTVARIABLENAMES must be unique.

%   Copyright 2002-2004 The MathWorks, Inc.
%   $Revision: 1.1.6.6 $  $Date: 2004/10/22 19:44:54 $

if (~iscell(checkboxLabels) || ~iscell(defaultVariableNames) || ...
    ~iscell(itemsToExport))
    error('MATLAB:export2wsdlg:CellArrayRequired',...
          ['CHECKBOXLABELS, DEFAULTVARIABLENAMES and '...
           'ITEMSTOEXPORT must all be cell arrays']);
end

checkBoxCount = length(checkboxLabels);

if checkBoxCount ~= length(defaultVariableNames) || ...
   checkBoxCount ~= length(itemsToExport)
    error('MATLAB:export2wsdlg:InputSizeMismatch',...
          ['CHECKBOXLABELS, DEFAULTVARIABLENAMES and '...
           'ITEMSTOEXPORT must all be the same length.']);
end

if length(unique(defaultVariableNames)) ~= checkBoxCount
    error('MATLAB:export2wsdlg:BadDefaultNames',...
          'Default variable names must be unique');
end

if (nargin > 3)
    title = varargin{1};
else
    title = 'Export To Workspace';
end

if (nargin > 4)
    selected = varargin{2};
    if ~islogical(selected)
        error('MATLAB:export2wsdlg:BadSelected',...
              'SELECTED must be a logical array');
    elseif length(selected) ~= checkBoxCount
        error('MATLAB:export2wsdlg:InputSizeMismatch',...
              'SELECTED must be the same length as ITEMSTOEXPORT');
    end
else
    selected = true(1, checkBoxCount);
end

if (nargin > 6)     % export functions
    functionlist = varargin{4}
    if length(functionlist) ~= checkBoxCount
        error('MATLAB:export2wsdlg:InputSizeMismatch',...
              'FUNCTIONLIST must be the same length as ITEMSTOEXPORT');
    end
else
    functionlist = cell(1, checkBoxCount);
end

hDialog = dialog('Visible', 'off', 'Name', title, 'WindowStyle', 'normal');
variableNames = createVarNames(defaultVariableNames);

if (nargin > 5)   % help button wanted
    helpButton = uicontrol(hDialog,'String', 'Help',...
                                   'Callback', {@HelpCallback, varargin{3}});
else
    helpButton = [];
end

cancelButton = uicontrol(hDialog,'String', 'Cancel',...
                                 'Callback', {@CancelCallback, hDialog});
okButton = uicontrol(hDialog,'String', 'OK', 'Fontweight', 'bold');

[checkBoxes, editFields] = layoutDialog(hDialog, okButton, cancelButton, helpButton, ...
                                        checkboxLabels, variableNames, ...
                                        selected, checkBoxCount); 

set(okButton, 'Callback', {@OKCallback, hDialog, checkBoxes, editFields, ...
                           itemsToExport, defaultVariableNames, functionlist});
set(hDialog, 'KeyPressFcn', {@KeyPressCallback, hDialog, checkBoxes, editFields, ...
                           itemsToExport, defaultVariableNames, functionlist});

if (length(checkBoxes) > 1)
    for i = 1:length(checkBoxes)
        set(checkBoxes{i}, 'Callback', {@CBCallback, checkBoxes, ...
                                        editFields, i});
    end
end

set(hDialog, 'HandleVisibility', 'callback', 'WindowStyle', 'modal', 'Resize', 'on');
set(hDialog, 'Visible', 'on');
if nargout > 0
    hDialogout = hDialog;
end

%----------------------------------------------------------------------------
function modifiedNames = createVarNames(defVariableNames)
    % Preallocating for speed
    modifiedNames = cell(1, length(defVariableNames));
    for i = 1:length(defVariableNames)
        modifiedNames{i} = computename(defVariableNames{i});
    end

%----------------------------------------------------------------------------
function name = computename(nameprefix)

if (evalin('base',['exist(''', nameprefix,''', ''var'');']) == 0)
    name = nameprefix;
    return
end

% get all names that start with prefix in workspace
workvars = evalin('base', ['char(who(''',nameprefix,'*''))']);
% trim off prefix name
workvars = workvars(:,length(nameprefix)+1:end); 

if ~isempty(workvars)
    % remove all names with suffixes that are "non-numeric"
    lessthanzero = workvars < '0';
    morethannine = workvars > '9';
    notblank = (workvars ~= ' ');
    notnumrows = any((notblank & (lessthanzero | morethannine)),2);
    workvars(notnumrows,:) = [];
end

% find the "next one"
if isempty(workvars)
    name = [nameprefix, '1'];
else
    nextone = max(str2num(workvars)) + 1;
    if isempty(nextone)
        name = [nameprefix, '1'];
    else
        name = [nameprefix, num2str(nextone)];
    end
end

%----------------------------------------------------------------------------
function OKCallback(obj, eventdata, dialog, cb, e, itm, defaultVariableNames, fcs)
    
    varnames = [];
    items = [];
    funcs = [];
    fieldnames = [];
    
    if (length(e) == 1)
          varnames{1} = get(e{1}, 'String');
          items{1} = itm{1};
          funcs{1} = fcs{1};
          fieldnames{1} = defaultVariableNames{1};
    else
        % we only care about items that are checked
        for i = 1:length(e)
            if get(cb{i}, 'Value') == 1
                varnames{end + 1} = get(e{i}, 'String');
                items{end + 1} = itm{i};
                funcs{end + 1} = fcs{i};
                fieldnames{end + 1} = defaultVariableNames{i};
            end
        end
    
        if (length(varnames) == 0)
            errordlg('You must check a box to export variables', ...
                     'Nothing selected','modal');
            return;
        end
    end
    
    %check for invalid and empty variable names
    badnames = [];
    emptynames = 0;
    emptystrmsg = '';
    badnamemsg = '';
    for i = 1:length(varnames)
        if strcmp('', varnames{i})
            emptynames = 1;
            emptystrmsg = sprintf('%s\n', ...
                'An empty string is not a valid choice for a variable name.');
        elseif ~isvarname(varnames{i})
            badnames{end + 1} = varnames{i};
        end
    end
    badnames = unique(badnames);
    
   
    if (length(badnames) > 0)
        if (length(badnames) == 1)
            badnamemsg = ['"' badnames{1} '"' ...
                      ' is not a valid MATLAB variable name.'];
        elseif (length(badnames) == 2)
            badnamemsg = ['"' badnames{1} '" and "' badnames{2} ...
                      '" are not valid MATLAB variable names.'];
        else 
            badnamemsg = [sprintf('"%s", ', badnames{1:end-2}),...
                      '"' badnames{end-1} ...
                      '" and "' badnames{end} ...
                      '" are not valid MATLAB variable names.', ];
        end
    end
    
    if (emptynames + length(badnames) > 0)
        dialogname = 'Invalid variable names';
        if (emptynames + length(badnames) == 1)
            dialogname = 'Invalid variable name';
        end
        errordlg([emptystrmsg badnamemsg], dialogname,'modal');    
        return; 
    end
    
    %check for names already in the workspace
    dupnames = [];
    for i = 1:length(varnames)
        if evalin('base',['exist(''',varnames{i},''', ''var'');'])
            dupnames{end + 1} = varnames{i};
        end
    end
    dupnames = unique(dupnames);
 
    if (length(dupnames) > 0)
        dialogname = 'Duplicate variable names';
        if (length(dupnames) == 1)
            queststr = ['"' dupnames{1} '"'...
                        ' already exists. Do you want to overwrite it?'];
            dialogname = 'Duplicate variable name';
        elseif (length(dupnames) == 2)
            queststr = ['"' dupnames{1} '" and "' dupnames{2} ...
                        '" already exist. Do you want to overwrite them?'];
        else
            queststr = [sprintf('"%s" , ', dupnames{1:end-2}), ...
                        '"' dupnames{end-1} '" and "' dupnames{end} ...
                        '" already exist. Do you want to overwrite them?'];
        end
        buttonName = questdlg(queststr, dialogname, 'Yes', 'No', 'Yes');
        if ~strcmp(buttonName, 'Yes') 
            return;
        end 
    end


    %Check for variable names repeated in the dialog edit fields
    [uniqueArray ignore uniqueIndex] = unique(varnames);
    for i = 1:length(uniqueArray)
        found = find(uniqueIndex == i);
        if (length(found) == 1) %variable name is not repeated
            index = found(1);
            if (isempty(funcs{index}))
                itemtoexport = items{index};
            else
                fun = funcs{index}
                itemtoexport = feval(fun{1}, fun{2:end})
            end
            assignin('base', varnames{found(1)}, itemtoexport);
        else %repeated variable names
            tempstruct = struct;
            for j = 1:length(found)
                index = found(j);
                if (isempty(funcs{index}))
                    itemtoexport = items{index};
                else
                    fun = funcs{index};
                    itemtoexport = feval(fun{1}, fun{2:end})
                end
                tempstruct.(fieldnames{index}) = itemtoexport;
            end
            assignin('base', varnames{found(1)}, tempstruct); 
        end
    end 
    
    disp('Variables have been created in the current workspace.')
    
    delete(dialog);
   
 
%----------------------------------------------------------------------------
function CBCallback(obj, eventdata, cb, e, num)
    if (get(cb{num}, 'Value') == 0)
        set(e{num}, 'Enable', 'off');
        set(e{num}, 'Backgroundcolor', [0.831373 0.815686 0.784314]);
    else
        set(e{num}, 'Enable', 'on');
        set(e{num}, 'Backgroundcolor', 'white');
    end
   
%----------------------------------------------------------------------------
function CancelCallback(obj, eventdata, dialog)
    delete(dialog);
   
%----------------------------------------------------------------------------
function KeyPressCallback(obj, eventdata, dialog, cb, e, itm, defaultVariableNames, fcs)
    asciiVal = get(dialog, 'CurrentCharacter');
    if ~isempty(asciiVal)
		if (asciiVal==32 || asciiVal==13)   % space bar or return is the "same" as OK
			OKCallback(obj, eventdata, dialog, cb, e, itm, defaultVariableNames, fcs);
		elseif (asciiVal == 27) % escape is the "same" as Cancel
			delete(dialog);
		end
    end
   
%----------------------------------------------------------------------------
function HelpCallback(obj, eventdata, helpfun)
     feval(helpfun{1}, helpfun{2:end});
   
%----------------------------------------------------------------------------
function [cb, e] = layoutDialog(hDlg, okBut, cancelBut, helpBut, checkboxLabels, ...
                                variableNames, selected, itemCnt)
    
    EXTENT_WIDTH_INDEX = 3;  % width is the third argument of extent
    
    POS_X_INDEX      = 1;
    POS_Y_INDEX      = 2;
    POS_WIDTH_INDEX  = 3;
    POS_HEIGHT_INDEX = 4;
    
    CONTROL_SPACING  = 5;
    EDIT_WIDTH       = 100;
    CHECK_BOX_WIDTH  = 20;
    DEFAULT_INDENT   = 20;
    
    okPos = get(okBut, 'Position');
    cancelPos = get(cancelBut, 'Position');
    if isempty(helpBut)
        helpPos = [0 0 0 0];
        helpWidth = 0;
    else
        helpPos = get(helpBut, 'Position');
        helpWidth = helpPos(POS_WIDTH_INDEX) + CONTROL_SPACING; 
    end
    longestCBExtent = 0;
    checkboxWidth = okPos(POS_WIDTH_INDEX) + cancelPos(POS_WIDTH_INDEX) + ...
                    helpPos(POS_WIDTH_INDEX);
    ypos = okPos(POS_HEIGHT_INDEX) + okPos(POS_Y_INDEX)+ 2*CONTROL_SPACING;
    cb = cell(itemCnt, 1);
    e = cell(itemCnt, 1);
    for i = itemCnt:-1:1
        % create uicontrols in reverse order. We will flip them later.
        e{i} = uicontrol(hDlg, 'Style', 'edit', 'String', variableNames{i}, ...
                               'BackgroundColor', 'white', ...
                               'HorizontalAlignment', 'left');
        cb{i} = uicontrol(hDlg, 'Style', 'checkbox', 'String', ...
                          checkboxLabels{i});
        check_pos = get(cb{i}, 'Position');
        check_pos(POS_Y_INDEX) = ypos;
        extent = get(cb{i}, 'Extent');
        width = extent(EXTENT_WIDTH_INDEX);
        check_pos(POS_WIDTH_INDEX) = width + CHECK_BOX_WIDTH;  
        set(cb{i}, 'Position', check_pos);
        edit_pos = get(e{i}, 'Position');
        edit_pos(POS_Y_INDEX) = ypos;
        edit_pos(POS_WIDTH_INDEX) = EDIT_WIDTH;
        % cursor doesn't seem to appear in default edit height
        edit_pos(POS_HEIGHT_INDEX) = edit_pos(POS_HEIGHT_INDEX) + 1;
        set(e{i}, 'Position', edit_pos);
        ypos = ypos + CONTROL_SPACING + edit_pos(POS_HEIGHT_INDEX);
        if width > longestCBExtent
            longestCBExtent = width;
        end
        if selected(i)
            set(cb{i}, 'Value', 1)
        else
            set(e{i}, 'Enable', 'off');
            set(e{i}, 'Backgroundcolor', [0.831373 0.815686 0.784314]);
        end                  
    end
    
    % if there is only one item, make it a text control instead of a checkbox
    if (itemCnt == 1)
        set(cb{1}, 'Style', 'text');
    end
    
    % Position edit boxes
    edit_x_pos = check_pos(POS_X_INDEX) + longestCBExtent + CONTROL_SPACING ...
                           + CHECK_BOX_WIDTH;
    for i = 1:itemCnt
        edit_pos = get(e{i}, 'Position');
        edit_pos(POS_X_INDEX) = edit_x_pos;
        set(e{i}, 'Position', edit_pos);
    end
    h_pos = get(hDlg, 'Position');
    
    h_pos(POS_WIDTH_INDEX) = max(edit_x_pos + edit_pos(POS_WIDTH_INDEX) + ...
                                 CHECK_BOX_WIDTH, okPos(POS_WIDTH_INDEX) + ...
                                 cancelPos(POS_WIDTH_INDEX) +  helpWidth + ...
                                 CONTROL_SPACING + (2 * DEFAULT_INDENT));
    h_pos(POS_HEIGHT_INDEX) = ypos;
    set(hDlg, 'Position', h_pos);
    
    % Make sure it is on-screen
    oldu = get(0,'Units');
    set(0,'Units','pixels');
    screenSize = get(0,'ScreenSize');
    set(0,'Units',oldu);
    outerPos = get(hDlg,'OuterPosition');
    if outerPos(1)+outerPos(3) > screenSize(3)
        outerPos(1) = screenSize(3) - outerPos(3);
    end
    if outerPos(2)+outerPos(4) > screenSize(4)
        outerPos(2) = screenSize(4) - outerPos(4);
    end
    set(hDlg, 'OuterPosition', outerPos);
    
    x_ok = (h_pos(POS_WIDTH_INDEX))/2 -  (okPos(POS_WIDTH_INDEX) + ... 
            helpWidth + CONTROL_SPACING + cancelPos(POS_WIDTH_INDEX))/2;
    okPos(POS_X_INDEX) = x_ok;
    set(okBut, 'Position', okPos);
    cancelPos(POS_X_INDEX) = okPos(POS_X_INDEX) + okPos(POS_WIDTH_INDEX) + ...
                                   CONTROL_SPACING;
    set(cancelBut, 'Position', cancelPos);
    if ~isempty(helpBut)
        helpPos(POS_X_INDEX) = cancelPos(POS_X_INDEX) + cancelPos(POS_WIDTH_INDEX) + ...
                                   CONTROL_SPACING;
        set(helpBut, 'Position', helpPos);
    end

    % Reorder the children so that tabbing makes sense
    children = get(hDlg, 'children');
    children = flipud(children);
    set(hDlg, 'children', children);