function oo_ = realtime_shock_decomposition(M_,oo_,options_,varlist,estim_params_)
% function oo_ = realtime_shock_decomposition(M_,oo_,options_,varlist,estim_params_)
% Computes shocks contribution to a simulated trajectory. The fields set are
% oo_.realtime_shock_decomposition, oo_.conditional_shock_decomposition and oo_.realtime_forecast_shock_decomposition.
% Subfields are arrays n_var by nshock+2 by nperiods. The
% first nshock columns store the respective shock contributions, column n+1
% stores the role of the initial conditions, while column n+2 stores the
% value of the smoothed variables.  Both the variables and shocks are stored
% in the order of declaration, i.e. M_.endo_names and M_.exo_names, respectively.
%
% INPUTS
%    M_:          [structure]  Definition of the model
%    oo_:         [structure]  Storage of results
%    options_:    [structure]  Options
%    varlist:     [char]       List of variables
%    estim_params_: [structure] characterizing parameters to be estimated
%
% OUTPUTS
%    oo_:         [structure]  Storage of results
%
% SPECIAL REQUIREMENTS
%    none

% Copyright © 2009-2026 Dynare Team
%
% This file is part of Dynare.
%
% Dynare is free software: you can redistribute it and/or modify
% it under the terms of the GNU General Public License as published by
% the Free Software Foundation, either version 3 of the License, or
% (at your option) any later version.
%
% Dynare is distributed in the hope that it will be useful,
% but WITHOUT ANY WARRANTY; without even the implied warranty of
% MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
% GNU General Public License for more details.
%
% You should have received a copy of the GNU General Public License
% along with Dynare.  If not, see <https://www.gnu.org/licenses/>.


if isfield(oo_,'shock_decomposition_info') && isfield(oo_.shock_decomposition_info,'i_var')
    if isfield (oo_,'realtime_conditional_shock_decomposition') ...
            || isfield (oo_,'realtime_forecast_shock_decomposition') ...
            || isfield (oo_,'realtime_shock_decomposition') ...
            || isfield (oo_,'shock_decomposition') ...
            || isfield (oo_,'conditional_shock_decomposition') ...
            || isfield (oo_,'initval_decomposition')
        error('realtime_shock_decomposition::squeezed shock decompositions are already stored in oo_')
    end
end

with_epilogue = options_.shock_decomp.with_epilogue;

% indices of endogenous variables
if isempty(varlist)
    varlist = M_.endo_names(1:M_.orig_endo_nbr);
end

[~, ~, index_uniques] = varlist_indices(varlist,M_.endo_names);
varlist = varlist(index_uniques);

% number of shocks
nshocks = M_.exo_nbr;

% parameter set
parameter_set = options_.parameter_set;
if isempty(parameter_set)
    if isfield(oo_,'posterior_mean')
        parameter_set = 'posterior_mean';
    elseif isfield(oo_,'mle_mode')
        parameter_set = 'mle_mode';
    elseif isfield(oo_,'posterior')
        parameter_set = 'posterior_mode';
    else
        error(['realtime_shock_decomposition: option parameter_set is not specified ' ...
               'and posterior mode is not available'])
    end
    options_.parameter_set=parameter_set; %store local copy to make sure subsequently called routines use same value
end

presample = max(1,options_.presample-1);
if isfield(options_.shock_decomp,'presample')
    my_presample = max(1,options_.shock_decomp.presample);
    presample = min(presample,my_presample);
end

forecast_ = options_.shock_decomp.forecast;
forecast_params=0;
if forecast_ && isfield(options_.shock_decomp,'forecast_params')
    forecast_params = options_.shock_decomp.forecast_params;
end
fast_realtime = 0;
if isfield(options_.shock_decomp,'fast_realtime')
    fast_realtime = options_.shock_decomp.fast_realtime;
end

save_realtime = options_.shock_decomp.save_realtime;
% array of time points in the range options_.presample+1:options_.nobs
if isnan(options_.nobs)
    error('realtime_shock_decomposition: the nobs-option must be set.')
end

zreal = zeros(M_.endo_nbr+length(M_.epilogue_names)*with_epilogue,nshocks+2,options_.nobs+forecast_);
zcond = zeros(M_.endo_nbr+length(M_.epilogue_names)*with_epilogue,nshocks+2,options_.nobs);

options_.selected_variables_only = 0; %make sure all variables are stored
options_.nograph=true;
options_.plot_priors=0;
init=1;
nobs = options_.nobs;

if forecast_ && any(forecast_params)
    M_forecast=M_;
    M_forecast.params = forecast_params;
    [~,~,~,~,~,dr_forecast] = dynare_resolve(M_forecast,options_,oo_.dr,oo_.steady_state,oo_.exo_steady_state,oo_.exo_det_steady_state);
end

gend0=0;

skipline()
skipline()
if isequal(fast_realtime,0)
    running_text = 'Realtime shock decomposition ';
else
    running_text = 'Fast realtime shock decomposition ';
end
newString=sprintf(running_text);
fprintf('%s',newString);

for j=presample+1:nobs
    %    evalin('base',['options_.nobs=' int2str(j) ';'])
    options_.nobs=j;
    if isequal(fast_realtime,0)
        [oo_local,M_,~,Smoothed_Variables_deviation_from_mean] = evaluate_smoother(parameter_set,varlist,M_,oo_,options_,estim_params_);
        gend = size(oo_local.SmoothedShocks.(M_.exo_names{1}),1);
    else
        if j<min(fast_realtime) && gend0<j
            options_.nobs=min(fast_realtime);
            [oo0,M_,~,Smoothed_Variables_deviation_from_mean0] = evaluate_smoother(parameter_set,varlist,M_,oo_,options_,estim_params_);
            gend0 = size(oo0.SmoothedShocks.(M_.exo_names{1}),1);
            options_.nobs=j;
        end

        if ismember(j,fast_realtime) && gend0<j
            [oo_local,M_,~,Smoothed_Variables_deviation_from_mean] = evaluate_smoother(parameter_set,varlist,M_,oo_,options_,estim_params_);
            gend = size(oo_local.SmoothedShocks.(M_.exo_names{1}),1);
            gend0 = gend;
            oo0=oo_local;
            Smoothed_Variables_deviation_from_mean0=Smoothed_Variables_deviation_from_mean;
        else
            if j>gend0
                if j>max(fast_realtime)
                    options_.nobs = nobs;
                else
                    options_.nobs=min(fast_realtime(fast_realtime>j));
                end
                [oo0,M_,~,Smoothed_Variables_deviation_from_mean0] = evaluate_smoother(parameter_set,varlist,M_,oo_,options_,estim_params_);
                gend0 = size(oo0.SmoothedShocks.(M_.exo_names{1}),1);
                options_.nobs=j;
            end

            gend = j;
            oo_local=oo0;
            Smoothed_Variables_deviation_from_mean = Smoothed_Variables_deviation_from_mean0(:,1:gend);
        end

    end
    % reduced form
    dr = oo_local.dr;

    if forecast_
        if any(forecast_params)
            Af = dr_forecast.ghx;
        else
            Af = dr.ghx;
        end
    end

    % initialization
    epsilon=NaN(nshocks,gend);
    for i = 1:nshocks
        epsilon(i,:) = oo_local.SmoothedShocks.(M_.exo_names{i})(1:gend);
    end
    epsilon=[epsilon zeros(nshocks,forecast_)];

    z = zeros(M_.endo_nbr,nshocks+2,gend+forecast_);

    z(:,end,1:gend) = Smoothed_Variables_deviation_from_mean;

    i_state = dr.order_var(M_.nstatic+(1:M_.nspred));
    for i=1:gend+forecast_
        if i > 1 && i <= M_.maximum_lag+1
            lags = min(i-1,M_.maximum_lag):-1:1;
        end

        if i > 1
            tempx = permute(z(:,1:nshocks,lags),[1 3 2]);
            m = min(i-1,M_.maximum_lag);
            tempx = [reshape(tempx,M_.endo_nbr*m,nshocks); zeros(M_.endo_nbr*(M_.maximum_lag-i+1),nshocks)];
            if i > gend
                z(:,nshocks+2,i) = Af(dr.inv_order_var,:)*z(i_state,nshocks+2,lags);
                z(:,1:nshocks,i) = Af(dr.inv_order_var,:)*tempx(i_state,:);
            else
                z(:,1:nshocks,i) = dr.ghx(dr.inv_order_var,:)*tempx(i_state,:);
            end
            lags = lags+1;
            z(:,1:nshocks,i) = z(:,1:nshocks,i) + dr.ghu(dr.inv_order_var,:).*repmat(epsilon(:,i)',M_.endo_nbr,1);
        end

        z(:,nshocks+1,i) = z(:,nshocks+2,i) - sum(z(:,1:nshocks,i),2);
    end

    if with_epilogue
        [z, epilogue_steady_state] = epilogue_shock_decomposition(z, M_, oo_);
        if ~isfield(oo_,'shock_decomposition_info') || ~isfield(oo_.shock_decomposition_info,'epilogue_steady_state')
            oo_.shock_decomposition_info.epilogue_steady_state = epilogue_steady_state;
        end
    end
    %% conditional shock decomp 1 step ahead
    z1 = zeros(M_.endo_nbr,nshocks+2);
    z1(:,end) = Smoothed_Variables_deviation_from_mean(:,gend);
    for i=gend
        z1(:,1:nshocks) = z1(:,1:nshocks) + dr.ghu(dr.inv_order_var,:).*repmat(epsilon(:,i)',M_.endo_nbr,1);
        z1(:,nshocks+1) = z1(:,nshocks+2) - sum(z1(:,1:nshocks),2);
    end
    if with_epilogue
        clear ztmp0
        ztmp0(:,1,:) = Smoothed_Variables_deviation_from_mean(:,1:gend-1);
        ztmp0(:,2,:) = Smoothed_Variables_deviation_from_mean(:,1:gend-1);
        ztmp = cat(3,cat(2,zeros(M_.endo_nbr,nshocks,gend-1),ztmp0),z1);
        z1  = epilogue_shock_decomposition(ztmp, M_, oo_);
        z1=squeeze(z1(:,:,end));
    end

    %% conditional shock decomp k step ahead
    if forecast_ && forecast_<j
        zn = zeros(M_.endo_nbr,nshocks+2,forecast_+1);
        zn(:,end,1:forecast_+1) = Smoothed_Variables_deviation_from_mean(:,gend-forecast_:gend);
        for i=1:forecast_+1
            if i > 1 && i <= M_.maximum_lag+1
                lags = min(i-1,M_.maximum_lag):-1:1;
            end

            if i > 1
                tempx = permute(zn(:,1:nshocks,lags),[1 3 2]);
                m = min(i-1,M_.maximum_lag);
                tempx = [reshape(tempx,M_.endo_nbr*m,nshocks); zeros(M_.endo_nbr*(M_.maximum_lag-i+1-1),nshocks)];
                zn(:,1:nshocks,i) = dr.ghx(dr.inv_order_var,:)*tempx(i_state,:);
                lags = lags+1;
                zn(:,1:nshocks,i) = zn(:,1:nshocks,i) + dr.ghu(dr.inv_order_var,:).*repmat(epsilon(:,i+gend-forecast_-1)',M_.endo_nbr,1);
            end

            zn(:,nshocks+1,i) = zn(:,nshocks+2,i) - sum(zn(:,1:nshocks,i),2);
        end
        if with_epilogue
            clear ztmp0
            ztmp0(:,1,:) = Smoothed_Variables_deviation_from_mean(:,1:gend-forecast_-1);
            ztmp0(:,2,:) = Smoothed_Variables_deviation_from_mean(:,1:gend-forecast_-1);
            ztmp = cat(3,cat(2,zeros(M_.endo_nbr,nshocks,gend-forecast_-1),ztmp0),zn);
            zn  = epilogue_shock_decomposition(ztmp, M_, oo_);
            zn=squeeze(zn(:,:,end-forecast_:end));
        end
        if ismember(j-forecast_,save_realtime)
            oo_.conditional_shock_decomposition.(['time_' int2str(j-forecast_)])=zn;
        end
    end
    %%

    if init
        zreal(:,:,1:j) = z(:,:,1:j);
    elseif j<nobs
        zreal(:,:,j) = z(:,:,gend);
    else
        zreal(:,:,j:end) = z(:,:,gend:end);
    end
    zcond(:,:,j) = z1;
    if ismember(j,save_realtime)
        oo_.realtime_shock_decomposition.(['time_' int2str(j)])=z;
    end

    if forecast_
        zfrcst(:,:,j+1) = z(:,:,gend+1);
        ootmp.realtime_forecast_shock_decomposition.(['time_' int2str(j)])=z(:,:,gend:end);
        if ismember(j,save_realtime)
            oo_.realtime_forecast_shock_decomposition.(['time_' int2str(j)]) = ...
                ootmp.realtime_forecast_shock_decomposition.(['time_' int2str(j)]);

        end
        if j>forecast_+presample
            %% realtime conditional shock decomp k step ahead
            ootmp.realtime_conditional_shock_decomposition.(['time_' int2str(j-forecast_)]) = ...
                zreal(:,:,j-forecast_:j) - ...
                ootmp.realtime_forecast_shock_decomposition.(['time_' int2str(j-forecast_)]);
            ootmp.realtime_conditional_shock_decomposition.(['time_' int2str(j-forecast_)])(:,end-1,:) = ...
                ootmp.realtime_conditional_shock_decomposition.(['time_' int2str(j-forecast_)])(:,end-1,:) + ...
                ootmp.realtime_forecast_shock_decomposition.(['time_' int2str(j-forecast_)])(:,end,:);
            ootmp.realtime_conditional_shock_decomposition.(['time_' int2str(j-forecast_)])(:,end,:) = ...
                zreal(:,end,j-forecast_:j);
            if ismember(j-forecast_,save_realtime)
                oo_.realtime_conditional_shock_decomposition.(['time_' int2str(j-forecast_)]) = ...
                    ootmp.realtime_conditional_shock_decomposition.(['time_' int2str(j-forecast_)]);
                oo_.shock_decomposition_info.realtime_conditional_shock_decomposition.parameter_set=options_.parameter_set;
            end
            if j==nobs
                for my_forecast_=(forecast_-1):-1:1
                    ootmp.realtime_conditional_shock_decomposition.(['time_' int2str(j-my_forecast_)]) = ...
                        zreal(:,:,j-my_forecast_:j) - ...
                        ootmp.realtime_forecast_shock_decomposition.(['time_' int2str(j-my_forecast_)])(:,:,1:my_forecast_+1);
                    ootmp.realtime_conditional_shock_decomposition.(['time_' int2str(j-my_forecast_)])(:,end-1,:) = ...
                        ootmp.realtime_conditional_shock_decomposition.(['time_' int2str(j-my_forecast_)])(:,end-1,:) + ...
                        ootmp.realtime_forecast_shock_decomposition.(['time_' int2str(j-my_forecast_)])(:,end,1:my_forecast_+1);
                    ootmp.realtime_conditional_shock_decomposition.(['time_' int2str(j-my_forecast_)])(:,end,:) = ...
                        zreal(:,end,j-my_forecast_:j);
                    if ismember(j-my_forecast_,save_realtime)
                        oo_.realtime_conditional_shock_decomposition.(['time_' int2str(j-my_forecast_)]) = ...
                            ootmp.realtime_conditional_shock_decomposition.(['time_' int2str(j-my_forecast_)]);
                        oo_.shock_decomposition_info.realtime_conditional_shock_decomposition.parameter_set=options_.parameter_set;
                    end
                end
            end

        end
    end

    prctdone=(j-presample)/(nobs-presample);
    if isoctave
        printf([running_text,' %3.f%% done\r'], prctdone*100);
    else
        s0=repmat('\b',1,length(newString));
        newString=sprintf([running_text,' %3.1f%% done'], prctdone*100);
        fprintf([s0,'%s'],newString);
    end
    init=0;
end
oo_.realtime_shock_decomposition.pool = zreal;
oo_.shock_decomposition_info.realtime_shock_decomposition.parameter_set=options_.parameter_set;
oo_.conditional_shock_decomposition.pool = zcond;
oo_.shock_decomposition_info.conditional_shock_decomposition.parameter_set=options_.parameter_set;
if forecast_
    oo_.realtime_forecast_shock_decomposition.pool = zfrcst;
    oo_.shock_decomposition_info.realtime_forecast_shock_decomposition.parameter_set=options_.parameter_set;
end
oo_.gui.ran_realtime_shock_decomposition = true;

skipline()
