% Copyright 2018-2024 by Romano Giannetti
% Copyright 2015-2024 by Stefan Lindner
% Copyright 2013-2024 by Stefan Erhardt
% Copyright 2007-2024 by Massimo Redaelli
%
% This file may be distributed and/or modified
%
% 1. under the LaTeX Project Public License and/or
% 2. under the GNU Public License.
%
% See the files gpl-3.0_license.txt and lppl-1-3c_license.txt for more details.

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% flow handling


%% styles
\ctikzset{bipole flow style/.style={}}
\tikzset{bipole flow style/.code={
        \ctikzset{bipole flow style/.style={#1}}
}}
\tikzset{bipole flow append style/.code={
        \ctikzset{bipole flow style/.append style={#1}}
}}

%% Options
\ctikzset{f^>/.style = {
        f={#1},
        \circuitikzbasekey/bipole/flow/direction = forward,
        \circuitikzbasekey/bipole/flow/x position = after,
        \circuitikzbasekey/bipole/flow/y position = above
    }
}

\ctikzset{f_>/.style = {
        f={#1},
        \circuitikzbasekey/bipole/flow/direction = forward,
        \circuitikzbasekey/bipole/flow/x position = after,
        \circuitikzbasekey/bipole/flow/y position = below
    }
}

\ctikzset{f>^/.style = {
        f={#1},
        \circuitikzbasekey/bipole/flow/direction = forward,
        \circuitikzbasekey/bipole/flow/x position = before,
        \circuitikzbasekey/bipole/flow/y position = above
    }
}

\ctikzset{f>_/.style = {
        f={#1},
        \circuitikzbasekey/bipole/flow/direction = forward,
        \circuitikzbasekey/bipole/flow/x position = before,
        \circuitikzbasekey/bipole/flow/y position = below
    }
}

\ctikzset{f^</.style = {
        f={#1},
        \circuitikzbasekey/bipole/flow/direction = backward,
        \circuitikzbasekey/bipole/flow/x position = after,
        \circuitikzbasekey/bipole/flow/y position = above
    }
}

\ctikzset{f_</.style = {
        f={#1},
        \circuitikzbasekey/bipole/flow/direction = backward,
        \circuitikzbasekey/bipole/flow/x position = after,
        \circuitikzbasekey/bipole/flow/y position = below
    }
}

\ctikzset{f<^/.style = {
        f={#1},
        \circuitikzbasekey/bipole/flow/direction = backward,
        \circuitikzbasekey/bipole/flow/x position = before,
        \circuitikzbasekey/bipole/flow/y position = above
    }
}

\ctikzset{f<_/.style = {
        f={#1},
        \circuitikzbasekey/bipole/flow/direction = backward,
        \circuitikzbasekey/bipole/flow/x position = before,
        \circuitikzbasekey/bipole/flow/y position = below
    }
}

\ctikzset{f</.style = { f={#1}, \circuitikzbasekey/bipole/flow/direction = backward} }
\ctikzset{f_/.style = { f={#1}, \circuitikzbasekey/bipole/flow/y position = below } }
\ctikzset{f>/.style = { f={#1}, \circuitikzbasekey/bipole/flow/direction = forward } }
\ctikzset{f^/.style = { f={#1}, \circuitikzbasekey/bipole/flow/y position = above } }

\newif\ifpgfcirc@do@f@symbols\pgfcirc@do@f@symbolstrue
\ctikzset{no f symbols/.code={\pgfcirc@do@f@symbolsfalse}}
\ctikzset{f symbols/.code={\pgfcirc@do@f@symbolstrue}}

\ctikzset{f/.code = {
        \pgfcirc@has@ftrue
        \ifpgf@circuit@bipole@override@source@vif
            \pgf@circuit@bipole@isvoltagefalse
            \pgf@circuit@bipole@iscurrentfalse
        \fi
        \pgfkeys{\circuitikzbasekey/bipole/flow/direction = forward,
            \circuitikzbasekey/bipole/flow/x position = after,
        \circuitikzbasekey/bipole/flow/y position = above }
        \pgfkeys{/tikz/circuitikz/bipole/flow/label/name={#1}}
        \ctikzsetvalof{bipole/flow/label/unit}{}
        \ifpgf@circ@siunitx
            \pgf@circ@handleSI{#1}
            \ifpgf@circ@siunitx@res
                \edef\pgf@temp{\pgf@circ@handleSI@val}
                \pgfkeyslet{/tikz/circuitikz/bipole/flow/label/name}{\pgf@temp}
                \edef\pgf@temp{\pgf@circ@handleSI@unit}
                \pgfkeyslet{/tikz/circuitikz/bipole/flow/label/unit}{\pgf@temp}
            \else
        \fi
        \else
    \fi
}
}

%% Output routine

\def\pgf@circ@drawflow{
    \pgfextra{
        \edef\pgf@circ@rounded@dir{\pgf@circ@direction}
        \def\pgfcircmathresult{\expandafter\pgf@circ@stripdecimals\pgf@circ@rounded@dir\pgf@nil}

        \ifnum\pgfcircmathresult >4 \ifnum\pgfcircmathresult <86
                \ifpgf@circuit@bipole@flow@below
                        \def\pgf@circ@dir{north west} \else \def\pgf@circ@dir{south east}
                \fi
        \fi\fi
        \ifnum\pgfcircmathresult >85 \ifnum\pgfcircmathresult <95
                \ifpgf@circuit@bipole@flow@below
                        \def\pgf@circ@dir{west} \else \def\pgf@circ@dir{east}
                \fi
        \fi\fi
        \ifnum\pgfcircmathresult >94 \ifnum\pgfcircmathresult <176
                \ifpgf@circuit@bipole@flow@below
                         \def\pgf@circ@dir{south west}\else \def\pgf@circ@dir{north east}
                \fi
        \fi\fi
        \ifnum\pgfcircmathresult >175 \ifnum\pgfcircmathresult <185
                \ifpgf@circuit@bipole@flow@below
                          \def\pgf@circ@dir{south}\else\def\pgf@circ@dir{north}
                \fi
        \fi\fi
        \ifnum\pgfcircmathresult >184 \ifnum\pgfcircmathresult <266
                \ifpgf@circuit@bipole@flow@below
                         \def\pgf@circ@dir{south east}\else\def\pgf@circ@dir{north west}
                \fi
        \fi\fi
        \ifnum\pgfcircmathresult >265 \ifnum\pgfcircmathresult <275
                \ifpgf@circuit@bipole@flow@below
                         \def\pgf@circ@dir{east}\else \def\pgf@circ@dir{west}
                \fi
        \fi\fi
        \ifnum\pgfcircmathresult >274 \ifnum\pgfcircmathresult <356
                \ifpgf@circuit@bipole@flow@below
                          \def\pgf@circ@dir{north east}\else\def\pgf@circ@dir{south west}
                \fi
        \fi\fi
        \ifnum\pgfcircmathresult <5
                \ifpgf@circuit@bipole@flow@below
                         \def\pgf@circ@dir{north}\else\def\pgf@circ@dir{south}
                \fi
        \fi
        \ifnum\pgfcircmathresult >355
                \ifpgf@circuit@bipole@flow@below
                         \def\pgf@circ@dir{north}\else\def\pgf@circ@dir{south}
                \fi
        \fi

        \ifpgf@circuit@bipole@flow@below
                \def\pgf@circ@bipole@flow@label@where{-90}
        \else
                \def\pgf@circ@bipole@flow@label@where{+90}
        \fi
        % export anchor position (if not needed, is always the same macro)
        \expandafter\xdef\csname pgfcirc@\pgfcirc@a@prefix-Flab-anchor\endcsname{\pgf@circ@dir}
    }

    \pgfextra{\def\pgf@temp{short}\edef\pgf@circ@temp{\ctikzvalof{bipole/kind}}}
    \ifx\pgf@circ@temp\pgf@temp%draw current at a short at middle of the line
        coordinate (pgfcirc@Ffrom@flat) at (\tikztostart)
        coordinate (pgfcirc@Fto@flat) at (\tikztotarget)
    \else% normal bipole or source
        \ifpgf@circuit@bipole@flow@before
            coordinate (pgfcirc@Ffrom@flat) at (\tikztostart)
            coordinate (pgfcirc@Fto@flat) at (pgfcirc@anchorstartnode)
        \else
            coordinate (pgfcirc@Ffrom@flat) at (pgfcirc@anchorendnode)
            coordinate (pgfcirc@Fto@flat) at (\tikztotarget)
        \fi
    \fi
    \pgfextra{
        \newdimen{\absfshift}
        \def\flow@offset{\ctikzvalof{flow/offset}\pgf@circ@Rlen}
        \absfshift=\flow@offset
        \ifpgf@circuit@bipole@flow@backward
            \pgfmathsubtract{\pgf@circ@rounded@dir}{180}
            \edef\pgf@circ@rounded@dir{\expandafter\pgf@circ@stripdecimals\pgfmathresult\pgf@nil}
        \fi
    }
    \ifpgf@circuit@bipole@flow@below
        coordinate (pgfcirc@Ffrom@up) at ($(pgfcirc@Ffrom@flat) ! \absfshift !-90: (pgfcirc@Fto@flat)$)
        coordinate (pgfcirc@Fto@up) at ($(pgfcirc@Fto@flat) ! \absfshift !90: (pgfcirc@Ffrom@flat)$)
    \else
        coordinate (pgfcirc@Ffrom@up) at ($(pgfcirc@Ffrom@flat) ! \absfshift !90: (pgfcirc@Fto@flat)$)
        coordinate (pgfcirc@Fto@up) at ($(pgfcirc@Fto@flat) ! \absfshift !-90: (pgfcirc@Ffrom@flat)$)
    \fi
    coordinate (\pgfcirc@a@prefix-Fpos) at ($(pgfcirc@Ffrom@up) ! \ctikzvalof{flow/distance} !(pgfcirc@Fto@up)$)
    \pgfextra{
        \absfshift=0.25\pgf@circ@Rlen% This is half size of the "flowarrow" shape!
    }
    coordinate (\pgfcirc@a@prefix-Ffrom) at ($(\pgfcirc@a@prefix-Fpos)!\absfshift!(pgfcirc@Ffrom@up)$)
    coordinate (\pgfcirc@a@prefix-Fto) at ($(\pgfcirc@a@prefix-Fpos)!\absfshift!(pgfcirc@Fto@up) $)
    %
    % coordinate (\pgfcirc@a@prefix-Fpos) at
    %     ([yshift=\flow@offset]$(\pgfcirc@a@prefix-Ffrom)! \ctikzvalof{flow/distance} !(\pgfcirc@a@prefix-Fto)$)
    % export the flow direction
    \pgfextra{\expandafter\xdef\csname pgfcirc@\pgfcirc@a@prefix-Farrow-direction\endcsname{\pgf@circ@rounded@dir}}
    % if the flow label is not empty (in which case we have already all the anchors)
    \pgf@circ@ifkeyempty{bipole/flow/label/name}\else
        % the flow arrow is really a node "flowarrow", not a real arrow
        \ifpgfcirc@do@f@symbols
            node[flowarrow, rotate=\pgf@circ@rounded@dir, anchor=center](Farrowpos) at (\pgfcirc@a@prefix-Fpos) {}
        \else
            node[flowarrow, rotate=\pgf@circ@rounded@dir, anchor=center,
                circuitikz/phantom@flowarrow](Farrowpos) at (\pgfcirc@a@prefix-Fpos) {}
        \fi
        node[anchor=\pgf@circ@dir, \circuitikzbasekey/bipole flow style]
        (\ctikzvalof{bipole/name}flow) at (Farrowpos.\pgf@circ@bipole@flow@label@where) {\pgf@circ@finallabels{flow/label}}
    \fi
    % adjust from and to before exporting --- it's much more simple like this then rework the algorithm above
    \ifpgf@circuit@bipole@flow@backward
        \pgfcirc@swap@coordinates{\pgfcirc@a@prefix-Ffrom}{\pgfcirc@a@prefix-Fto}
    \fi

}

\endinput
