Thesis Book

\documentclass[fleqn,a4paper,12pt,oneside,onecolumn]{book}

% layout margin
\usepackage[inner=4cm, outer=3cm, top=3cm, bottom=3cm]{geometry}
% font family 'times new roman'-like, PLEASE REMOVE THESE MADNESS!
\usepackage{newtxtext,newtxmath}
% Package terkait AMS dan matematika
\usepackage{amsmath}
% load image package
\usepackage{graphicx}
% hanging indent
\usepackage{hanging}
% chapter style centering
\usepackage[explicit]{titlesec}
\titleformat{\chapter}[hang]
    {\centering\large\bfseries}
    {\chaptertitlename\ \thechapter\;\;\;} 
    {0pt}
    {\centering\MakeUppercase{#1}}
\titlespacing{\chapter}{0pt}{-24pt}{*0}
% section size
\titleformat{\section}
    {\normalsize\bfseries}
    {\thesection\;\;\;} 
    {0pt}
    {#1}

% TODO: page numbering position center bottom just about 1.5cm
% page style
\pagestyle{plain}
% roman chapter numbering
\renewcommand{\thechapter}{\Roman{chapter}} 
% package bahasa
\usepackage[english]{babel} % TODO: nanti ganti ke indo...
% \usepackage[indonesian]{babel}
% fancy header, untuk mengganti tampilan header
\usepackage{fancyhdr}
% Package untuk menampilkan daftar pustaka
% TODO: add indonesian format for biblatex, see https://tex.stackexchange.com/questions/200932/what-is-the-most-appropriate-way-to-configure-biblatex-for-use-with-an-unsupport
\usepackage[
backend=biber,
style=numeric,
sorting=nyt
]{biblatex}
\usepackage{csquotes}
\addbibresource{sample.bib}
% Package hyperlinks dokumen
\usepackage{hyperref}
% indent first paragraph
\usepackage{indentfirst}
%----------------------------------------
% JUDUL DALAM BAHASA INDONESIA
\AtBeginDocument{\renewcommand{\contentsname}{DAFTAR ISI}}
\AtBeginDocument{\renewcommand{\listfigurename}{DAFTAR GAMBAR}}
\AtBeginDocument{\renewcommand{\listtablename}{DAFTAR TABEL}}
\AtBeginDocument{\renewcommand{\chaptername}{BAB}}
\AtBeginDocument{\renewcommand{\bibname}{DAFTAR PUSTAKA}}
% \AtBeginDocument{\renewcommand{\appendixpagename}{LAMPIRAN}}
% \AtBeginDocument{\renewcommand{\appendixname}{LAMPIRAN}}
% \AtBeginDocument{\renewcommand{\appendixtocname}{LAMPIRAN}}
\AtBeginBibliography{\vspace*{\baselineskip}}
%
\renewcommand{\thefootnote}{\arabic{footnote}}
\renewcommand{\index}{\arabic{indeks}}
%----------------------------------------
%-----------------------------------------
% month abbreviation; Please remove this abomination if possible 😡
\usepackage{xifthen}
\newcommand{\ifequals}[3]{\ifthenelse{\equal{#1}{#2}}{#3}{}}
\newcommand{\case}[2]{#1 #2} % Dummy, so \renewcommand has something to overwrite...
\newenvironment{switch}[1]{\renewcommand{\case}{\ifequals{#1}}}{}
\newcommand{\monthabv}[2]{
    \begin{switch}{#1}
        \case{Januari}{Jan}
        \case{Februari}{Feb}
        \case{Maret}{Mar}
        \case{April}{Apr}
        \case{Mei}{Mei}
        \case{Juni}{Jun}
        \case{Juli}{Jul}
        \case{Agustus}{Ags}
        \case{September}{Sep}
        \case{Oktober}{Okt}
        \case{November}{Nov}
        \case{Desember}{Des}
        #2
    \end{switch}
}
%-----------------------------------------
% custom command
\newcommand{\titlename}{Menggunakan GAIA DR3 Untuk Mengkonstrain Kerapatan Materi Gelap di Dekat Matahari dalam Kerangka MOND}
\newcommand{\authorname}{Muhammad Ali Syaifudin}
\newcommand{\authorid}{20321005}
\newcommand{\department}{Program Studi Magister Astronomi}
\newcommand{\completionyear}{2023}
\newcommand{\completionmonth}{Januari}
\newcommand{\completiondate}{\monthabv{\completionmonth}{\completionyear}}
\newcommand{\fullcompletiondate}{5 \completionmonth\ \completionyear}
%-----------------------------------------
\begin{document}
% Bagian Awal Buku
\frontmatter
\clearpage
\input{judul.tex}
\pagenumbering{roman}
\input{abstrak.tex}
\input{abstract.tex}
\input{pengesahan.tex}
\input{pedoman.tex}
\input{dedikasi.tex}
\input{pengantar.tex}
% Daftar-daftar
\tableofcontents
\listoffigures
\listoftables
\input{singkatan.tex}
% Bagian Utama Buku
\mainmatter
\input{bab1.tex}
\input{bab2.tex}
% Bagian Akhir Buku
\backmatter
\printbibliography
\end{document}