%CODEGENERATION.GENMFUNINERTIA Generate M-function for robot inertia matrix
%
% cGen.genmfuninertia() generates a robot-specific M-function to compute
% robot inertia matrix.
%
% Notes::
% - Is called by CodeGenerator.geninertia if cGen has active flag genmfun
% - The inertia matrix is stored row by row to avoid memory issues.
% - The generated M-function recombines the individual M-functions for each row.
% - Access to generated function is provided via subclass of SerialLink 
%   whose class definition is stored in cGen.robjpath.
%
% Author::
%  Joern Malzahn, (joern.malzahn@tu-dortmund.de)
%
% See also CodeGenerator.CodeGenerator, CodeGenerator.gencoriolis.

% Copyright (C) 2012-2014, by Joern Malzahn
%
% This file is part of The Robotics Toolbox for Matlab (RTB).
%
% RTB is free software: you can redistribute it and/or modify
% it under the terms of the GNU Lesser General Public License as published by
% the Free Software Foundation, either version 3 of the License, or
% (at your option) any later version.
%
% RTB 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 Lesser General Public License for more details.
%
% You should have received a copy of the GNU Leser General Public License
% along with RTB.  If not, see <http://www.gnu.org/licenses/>.
%
% http://www.petercorke.com
%
% The code generation module emerged during the work on a project funded by
% the German Research Foundation (DFG, BE1569/7-1). The authors gratefully 
% acknowledge the financial support.

function [] = genmfuninertia(CGen)

%% Does robot class exist?
if ~exist(fullfile(CGen.robjpath,[CGen.getrobfname,'.m']),'file')
    CGen.logmsg([datestr(now),'\tCreating ',CGen.getrobfname,' m-constructor ']);
    CGen.createmconstructor;
    CGen.logmsg('\t%s\n',' done!');
end

%%
CGen.logmsg([datestr(now),'\tGenerating m-function for the robot inertia matrix row' ]);

q = CGen.rob.gencoords;
nJoints = CGen.rob.n;

for kJoints = 1:nJoints
    CGen.logmsg(' %s ',num2str(kJoints));
    symname = ['inertia_row_',num2str(kJoints)];
    fname = fullfile(CGen.sympath,[symname,'.mat']);
    
    if exist(fname,'file')
        tmpStruct = load(fname);
    else
        error ('genmfuninertia:SymbolicsNotFound','Save symbolic expressions to disk first!')
    end
    
    funfilename = fullfile(CGen.robjpath,[symname,'.m']);
    
    matlabFunction(tmpStruct.(symname),'file',funfilename,...              % generate function m-file
        'outputs', {'Irow'},...
        'vars', {'rob',[q]});
    hStruct = createHeaderStructRow(CGen.rob,kJoints,symname);                 % replace autogenerated function header
    replaceheader(CGen,hStruct,funfilename);
    
    
end
CGen.logmsg('\t%s\n',' done!');


CGen.logmsg([datestr(now),'\tGenerating full inertia matrix m-function']);
    
    funfilename = fullfile(CGen.robjpath,'inertia.m');
    hStruct = createHeaderStructFullInertia(CGen.rob,funfilename);
    
    fid = fopen(funfilename,'w+');
    
    fprintf(fid, '%s\n', ['function I = inertia(rob,q)']);                 % Function definition
    fprintf(fid, '%s\n',constructheaderstring(CGen,hStruct));                   % Header
   
    fprintf(fid, '%s \n', 'I = zeros(length(q));');                        % Code
    for iJoints = 1:nJoints
        funcCall = ['I(',num2str(iJoints),',:) = ','rob.inertia_row_',num2str(iJoints),'(q);'];
        fprintf(fid, '%s \n', funcCall);
    end
    
    fclose(fid);
    
    CGen.logmsg('\t%s\n',' done!');           
end

function hStruct = createHeaderStructRow(rob,curJointIdx,fName)
[~,hStruct.funName] = fileparts(fName);
hStruct.shortDescription = ['Computation of the robot specific inertia matrix row for corresponding to joint ', num2str(curJointIdx), ' of ',num2str(rob.n),'.'];
hStruct.calls = {['Irow = ',hStruct.funName,'(rob,q)'],...
    ['Irow = rob.',hStruct.funName,'(q)']};
hStruct.detailedDescription = {'Given a full set of joint variables this function computes the',...
                               ['inertia matrix row number ', num2str(curJointIdx),' of ',num2str(rob.n),' for ',rob.name,'.']};
hStruct.inputs = { ['rob: robot object of ', rob.name, ' specific class'],...
                   ['q:  ',int2str(rob.n),'-element vector of generalized'],...
                   '     coordinates',...
                   'Angles have to be given in radians!'};
hStruct.outputs = {['Irow:  [1x',int2str(rob.n),'] row of the robot inertia matrix']};
hStruct.references = {'1) Robot Modeling and Control - Spong, Hutchinson, Vidyasagar',...
    '2) Modelling and Control of Robot Manipulators - Sciavicco, Siciliano',...
    '3) Introduction to Robotics, Mechanics and Control - Craig',...
    '4) Modeling, Identification & Control of Robots - Khalil & Dombre'};
hStruct.authors = {'This is an autogenerated function!',...
    'Code generator written by:',...
    'Joern Malzahn',...
    '2012 RST, Technische Universitaet Dortmund, Germany',...
    'http://www.rst.e-technik.tu-dortmund.de'};
hStruct.seeAlso = {'coriolis'};
end

function hStruct = createHeaderStructFullInertia(rob,fname)
[~,hStruct.funName] = fileparts(fname);
hStruct.shortDescription = ['Inertia matrix for the ',rob.name,' arm.'];
hStruct.calls = {['I = ',hStruct.funName,'(rob,q)'],...
    ['I = rob.',hStruct.funName,'(q)']};
hStruct.detailedDescription = {'Given a full set of joint variables the function computes the',...
                               'inertia Matrix of the robot.'};
hStruct.inputs = { ['rob: robot object of ', rob.name, ' specific class'],...
                   ['q:  ',int2str(rob.n),'-element vector of generalized'],...
                   '     coordinates',...
                   'Angles have to be given in radians!'};
hStruct.outputs = {['I:  [',int2str(rob.n),'x',int2str(rob.n),'] inertia matrix']};
hStruct.references = {'1) Robot Modeling and Control - Spong, Hutchinson, Vidyasagar',...
    '2) Modelling and Control of Robot Manipulators - Sciavicco, Siciliano',...
    '3) Introduction to Robotics, Mechanics and Control - Craig',...
    '4) Modeling, Identification & Control of Robots - Khalil & Dombre'};
hStruct.authors = {'This is an autogenerated function!',...
    'Code generator written by:',...
    'Joern Malzahn',...
    '2012 RST, Technische Universitaet Dortmund, Germany',...
    'http://www.rst.e-technik.tu-dortmund.de'};
hStruct.seeAlso = {'coriolis'};
end
