[Tex/LaTex] Add fourth argument to address command in moderncv class

Question

I'm trying to add a fourth argument to the address command in the moderncv class. I've looked for a solution around the internet and tried a few things including attempting to edit the moderncv class file, but I haven't got anything to work properly. The closest I came was using this method; How can I add a new address line within moderncv style, which did get the end result that I wanted except that the last line of the address (Country) and the phone are on the same line. The code and result it produces are as follows:

\documentclass[12pt,a4paper,sans]{moderncv}
\moderncvtheme[blue]{classic}
\usepackage[scale=0.75]{geometry}
\usepackage{etoolbox}

\makeatletter
\patchcmd{\makecvtitle}{\ifthenelse{\equal{\@addresscountry}{}}}%
{\ifstrempty{\@addresscountry}}{}{}
\makeatother

\firstname{John}
\familyname{Smith}
\title{Curriculum Vitae}
\address{42 Apartment complex}{Street}{City\\Country}
\mobile{0000000000}
\email{email@email.email}

Does anyone have any solution to offer, preferably to add a fourth argument to the command, but I would take an amendment to the above code that would move the country onto its own line? Any help is appreciated.

Answer 1

Maybe something like this if I've understood correctly:

\documentclass[12pt,a4paper,sans]{moderncv}
\moderncvtheme[blue]{classic}
\usepackage[scale=0.75]{geometry}
\usepackage{etoolbox}

\makeatletter
\RenewDocumentCommand{\address}{mG{}G{}G{}}{%
  \def\@addressapartment{#1}\def\@addressstreetonly{#2}\def\@addresscity{#3}\def\@addresscountry{#4}%
  \def\@addressstreet{%
  \ifthenelse{\isundefined{\@addressapartment}}{}{\@addressapartment}%
  \ifthenelse{\isundefined{\@addressstreetonly}}{}{\makenewline\@addressstreetonly}%
  }}
\makeatother

\firstname{John}
\familyname{Smith}
\title{Curriculum Vitae}
\address{42 Apartment complex}{Street}{City}{Country}
\mobile{0000000000}
\email{email@email.email}

\begin{document}
    \makecvtitle
\end{document}