function SPR(cond)
% =========================================================================
%                            function SPR
%                Experiment = Self-Paced/RSVP Paradigm
%                =========================================
%                      Assumes 60 Hz refresh rate
%                ** PLEASE ADJUST MONITOR REFRESH RATE **
%                =========================================
%
%% EXP 1: Experiment Title
% Experiment description
%
%% Code Authors:
%  Thiago Oliveira da Motta Sampaio (ACESIN/LAPEX/UFRJ/INSERM/NeuroSpin)
%  Virginie van Wassenhove (CEA/NeuroSpin)
%==========================================================================

%% Rappel des "response pads" en MEG:
% (On pose Port1= 888, Port2= 48353 et Port3= 48369)
%
% Couleur:  blue  /  red   /  green  /  yellow  /  blue(thumb)   
% LEFT:     [64]  / [-128] /   [64]  /   [32]   /   [16]
% Port:    Port3  /  Port3 /  Port2  /  Port2   /  Port2
% RIGHT:    [8]   / [64]   /   [32]  /   [16]   /   [8]
% Port :   Port2  /Port1+1 / Port1+1 /  Port1+1 /  Port1+1
% RQ1: Port3 donne un biais de 152 qu'il faut donc soustraire ? la
% lecture !
% RQ2: Pas les m?mes n? pour l'ordi d'acquisition MEG 

%% EEG Ports and Triggers 
% PC stim port definition:
  %PCport1= hex2dec('378'); % &H378 -> 888 en base 10
  %PCport2= hex2dec('BCE1'); %&HBCE1 -> 48353 en base 10
  %PCport3= hex2dec('BCF1'); % &HBCF1 -> 48369 en base 10
  
%% Some frequently used KeyCodes for MAC Portability
% ESC       - 41
% SPACE     - 44
% 1         - 30
% 2         - 31
% 3         - 32
% 4         - 33
% Q         - 20
% P         - 19
% A         - 4
% L         - 15
% K         - 14
% J         - 13
  
  
%%
try
    KbName('UnifyKeyNames');
    escapeKey = KbName('ESCAPE');
    AssertOpenGL;
    %----------------------------------------------------------------------
    %               - PROMPT USER FOR DATA FILE NAME -
    %----------------------------------------------------------------------
    dataFile='tmp';
    promptUser=true;
    
    while promptUser
        prompt=inputdlg('ID','Output File',1,{'tmp'});
        if isempty(prompt);
            disp(['Cancel experiment ...']);
            return;
        else
            initials=prompt{1};
        end
        
        tmpFile = [initials,'_SPR.mat'];
        
        if ~exist(tmpFile);
            promptUser = false;
        else
            replace=questdlg(['Um arquivo com o mesmo nome já existe. Gostaria de substituí-lo?']);
            if strcmp( replace, 'Yes' );
                dataFile = tmpFile;
                promptUser = false;
            end
        end
    end
    %----------------------------------------------------------------------
    %                  LOADING VERSION/SUBJECT PARAMS
    %----------------------------------------------------------------------
    
    if exist('cond')
        load([initials, '_SPR_params_', cond, '.mat']);
        dataFile = [initials,'_SPR_data_', cond];
    else
        display('error: specify condition');
    end
    
    psycdata = [];
    
    %----------------------------------------------------------------------
    %                     - INITIALIZE DISPLAY -
    %----------------------------------------------------------------------
    
    % affichage warning/error/autocalibration settings
    Screen('Preference','SkipSyncTests', 0);
    Screen('Preference','VisualDebugLevel', 1);
    Screen('Preference', 'ConserveVRAM', 4096);
    screens = Screen('Screens');
    
    % Size of window: Default to fullscreen:
    screenNumber = 0;
    [w,screenRect] = Screen('OpenWindow', screenNumber,0,[],32,2);

    % blending (pour antialiasing)
    Screen('BlendFunction', w, GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
    
    % Display frequency
    fps = Screen('FrameRate',w);      % frames per second
    ifi = Screen('GetFlipInterval', w);
    if fps == 0
        fps = 1/ifi;
    end
    
    % Screen size in cm
    sH = 24;             % screen height (cm)
    sW = 25;             % screen width (cm)
    
    %
    whichScreen = max(Screen('Screens'));
    [w,wRect] = Screen('OpenWindow', whichScreen);
    
    % Color Defs
    white = WhiteIndex(w);
    black = BlackIndex(w);
    gray = (white+black)/2;
    red     = [255 0 0 ];
    green   = [0 255 0];
    blue    = [0 0 255];
    yellow  = [255 255 0];
    grayish = [100 100 100];
    ft_color  = white;
    bck_color   = black;
    
    % Fixation Dot
    % dim + pos defs
    dW = wRect(3) - wRect(1);
    dH = wRect(4) - wRect(2);
    %

    pixel = dH/sH;
    x0 = dW/2;
    y0 = dH/2;
    fix_size = 0.2*pixel;
    fix_pos  = [x0-fix_size/2 y0-fix_size/2 x0+fix_size/2 y0+fix_size/2];
    fix_col  = black;

    % choice positions TO CHECK
    x1 = x0 - 300; 
    x2 = x0 + 150; 
    y1 = y0 - 100; 
    y2 = y0 - 150; 
    
    %
    Screen('FillRect',w, bck_color);
    Screen('Flip', w);
    % 
    %%
    %----------------------------------------------------------------------
    %                     - INSTRUCTIONS SCREEN -
    %----------------------------------------------------------------------
    
    HideCursor;
    inst1 = 'Pressione ESPALJO para continuar';
    inst2 = 'PAUSA';
    inst3 = 'Fim do Experimento. Obrigado pela participação';
    %
    clear RestrictKeysForKbCheck;
    RestrictKeysForKbCheck([41, 44]);
    Screen('FillRect',w, bck_color);
    Screen('TextFont',w, 'Arial');
    Screen('TextSize',w, 28);
    Screen('DrawText', w, inst1, x0-300, y0, ft_color);
    Screen('FillOval',w, fix_col, fix_pos);
    Screen('Flip', w);
    KbWait;
    
    %----------------------------------------------------------------------
    %                     - STIMULI PRESENTATION -
    %----------------------------------------------------------------------
    
    % - START LOOP -
    priorityLevel=MaxPriority(w);
    Priority(priorityLevel);
    
    for block = 1:1;
        
        % Initialize Data Matrix
        psycdata = [];        
        for trial=1:length(expMat);
            
            clear RestrictKeysForKbCheck;
            RestrictKeysForKbCheck([41, 44]);            
            %
            Screen('FillOval', w, fix_col, fix_pos);
            [nx, ny, bbox] = DrawFormattedText(w, ' + ', 'center', 'center', 255);         
            Screen('Flip', w);
            WaitSecs(1);
            %
            [nx, ny, bbox] = DrawFormattedText(w, '  ', 'center', 'center', 255);
            Screen('Flip', w);
            WaitSecs(.03);
            
            % initialize trial RT
            t0  = GetSecs;
            
            for cnum = 3:9 
                promptUser  = true;
                [nx, ny, bbox] = DrawFormattedText(w, lista{expMat(trial, cnum), expMat(trial,2)}, 'center', 'center', 255);
                Screen('Flip', w);
                WaitSecs(0.2); 
                while (promptUser)
                     KbWait;
                    [keyIsDown,secs,keyCode]=KbCheck;
                    WaitSecs(0.001); % delay to prevent CPU hogging
                   if keyIsDown;
                        psycdata{block}(trial,cnum) = secs-t0; % col 3:9 RT
                        promptUser  = false;
                   end
                end
            end
            %
            %WaitSecs(0.03) %???? tempo
            RestrictKeysForKbCheck([14, 15, 41]);
            
            %                           TASK
            
            [nx, ny, bbox] = DrawFormattedText(w, lista{expMat(trial, 10), expMat(trial,2)}, 'center', 'center', red); 
            Screen('Flip', w);
            %WaitSecs(.03);
            
            promptUser  = true;
            while (promptUser)
                KbWait;
                [keyIsDown,secs,keyCode]=KbCheck;
                if keyIsDown;
                    keyNum = find(keyCode);
                    psycdata{block}(trial,10) = secs-t0; % col 2 RT
                    
                    if keyNum == 14;     % Q
                        psycdata{block}(trial,11) = 1; % col 11 choix
                    elseif keyNum == 15; % P
                        psycdata{block}(trial,11) = 2; % col 11 choix
                    elseif  keyCode(escapeKey)
                        error('Esc key was pressed');       % ESCAPE program
                    break;
                    end
                    promptUser  = false;
                end
            end     
            %
        end % trial
        
        save(dataFile,'expMat','psycdata');
        
    %----------------------------------------------------------------------
    %                  - BREAK AND END OF EXPERIMENT -
    %----------------------------------------------------------------------
    
        if block > 1   
            % participant's break time after each block
            Screen('FillRect',w, bck_color);
            Screen('TextFont',w, 'Arial');
            Screen('TextSize',w, 30);
            Screen('DrawText', w, inst2, x0-50, y0-10, ft_color);
            Screen('Flip', w);
            WaitSecs(2)
            KbWait;
            Screen('DrawText', w, inst1, x0-300, y0, ft_color);
            Screen('FillOval',w, fix_col, fix_pos);
            Screen('Flip', w);
            WaitSecs(2)
            KbWait;
        else
            Screen('FillRect',w, black);
            Screen('TextFont',w, 'Arial');
            Screen('TextSize',w, 30);
            Screen('DrawText', w, inst3, x0-350, y0, ft_color);
            Screen('Flip', w);
            WaitSecs(3);
        end
        %
    end % block
    
    %% DATA correction
    
    % initialize temporary data matrix
    tmpdata = []

    % Copy Subject Data from psycdata
    tmpdata = psycdata{1,1};

    % merge trial number and stimuli number with subject data
    tmpdata(:,1) = expMat(:,1);
    tmpdata(:,2) = expMat(:,2);
    
    % As Rts are cumulative (2nd segment RT = 1st + 2nd segment RT) we need
    % to calculate segment RT from sentence check points.
    tmpdata(:,4) = tmpdata(:,4)-tmpdata(:,3)
    tmpdata(:,5) = tmpdata(:,5)-tmpdata(:,4)-tmpdata(:,3) % = tmpdata 5th column should be equal to tmpdata 5th column - tmpdata 4rd column and so on....
    tmpdata(:,6) = tmpdata(:,6)-tmpdata(:,5)-tmpdata(:,4)-tmpdata(:,3)
    tmpdata(:,7) = tmpdata(:,7)-tmpdata(:,5)-tmpdata(:,4)-tmpdata(:,6)-tmpdata(:,3)
    tmpdata(:,8) = tmpdata(:,8)-tmpdata(:,5)-tmpdata(:,4)-tmpdata(:,6)-tmpdata(:,7)-tmpdata(:,3)
    tmpdata(:,9) = tmpdata(:,9)-tmpdata(:,5)-tmpdata(:,4)-tmpdata(:,6)-tmpdata(:,7)-tmpdata(:,8)-tmpdata(:,3)
    tmpdata(:,10) = tmpdata(:,10)-tmpdata(:,4)-tmpdata(:,3)-tmpdata(:,5)-tmpdata(:,6)-tmpdata(:,7)-tmpdata(:,8)-tmpdata(:,9)
    
    % save temporary data matrix as the final subject data matrix 'subjdata'
    subjdata = tmpdata
    
    % clear base matrixes
    clear psycdata, clear expMat, clear tmpdata
    
    %%% END RT Correction %%%
    %% SUBJECT DATA ANALYSIS
    
    
    
    % END SUBJ DATA ANALYSIS
    
    
    %%
    
    % Access DATA folder and save datafile
    cd DATA_SPR/
    save(dataFile, 'initials', 'subjdata');
    
    % Closing the Experiment
    Priority(0);
    ShowCursor;
    clear mex;
    Screen('CloseAll');
    
    %----------------------------------------------------------------------
    %                        - CATCH ERRORS -
    %----------------------------------------------------------------------
catch
    ShowCursor;
    Screen('CloseAll');
    disp(['CRITICAL ERROR: ' lasterr ]);
    disp(['Exiting program ...']);
    rethrow(lasterror);
end