New command with cases / conditionals / 'if… then's

Question

I defined a command to insert figures easier and according to some college formatting. It is working just fine, but I am having a problem trying to add a conditional statement. The command is this:

%\figura{fig-location}{caption}{width(0-1)}{Source(if own, leavy empty)}{label}
     \newcommand{\figura}[5]{
        \begin{figure}[H]
            \begin{minipage}{\textwidth}
                \caption[#2]{\raggedright #2}
                \label{fig:#5}
                \begin{center}
                    \includegraphics[width=#3\textwidth]{#1}\\
                \end{center}
                \textbf{Fuente: }#4
            \end{minipage}
        \end{figure}
     }

The output is as I want it to be, here is an example:

However, some figures are made by me, and I don't need to cite the source of such figures. Source is the word Fuente (Spanish). So I want to modify the command with a conditional so that when I leave the #4 argument empty, it does not print the word Fuente: under the figure. Id est:

• If #4 =, then do nothing.

• If #4 = something, then write under the figure Fuente: #4.

Is it possible to realise the above pseudocode? If so, how can I?

I found this in another post, but it only works with the exact word "something", I need it to work with anything different from an empty argument:

\documentclass{article}
\usepackage{xstring}

\newcommand{\example}[2]{%
    \IfEqCase{#1}{%
        {}{$\sqrt{#2}$}%
        {something}{Fuente: XYZ}%
        % you can add more cases here as desired
    }
     [\PackageError{tree}{Undefined option to tree: #1}{}]%
}%
\begin{document}

\example{}{None}
\example{something}{}


\end{document}

Answer 1

UPDATE.

I made it, here is the new version of the command:

\newcommand{\figura}[5]{
    \begin{figure}[H]
        \begin{minipage}{\textwidth}
            \caption[#2]{\raggedright #2}
            \label{fig:#5}
            \begin{center}
                \includegraphics[width=#3\textwidth]{#1}\\
            \end{center}            
              \ifstrequal{#4}{}%
              {}%
              {\textbf{Fuente: }#4}%            
        \end{minipage}
    \end{figure}
}