\def\hs{\hspace{0.4 cm}}

\documentclass[aspectratio=169,usenames,dvipsnames]{beamer}

\usetheme{lined}
\usecolortheme{beaver}
\setbeamertemplate{footline}[default]
\beamertemplatenavigationsymbolsempty

\title{
    \makebox[0.525\textwidth][s]{\huge\textbf{M I N I S C R I P T}}\\
    \makebox[0.525\textwidth][s]{Custody. Computable. Composeable.}
}
\author{
    Andrew Poelstra\\
    \small
    Director of Research, Blockstream
}
\date{November 6, 2021}

\usepackage{colortbl}
\usepackage{multirow}
\usepackage{tikz}

\tikzset{
    every node/.style = {
        shape=rectangle,
        rounded corners,
        draw,
        top color = white,
        label distance=-0.5ex,
    },
    comb/.style = { bottom color = blue!20 },
    term/.style = { bottom color = red!50 },
    F/.style = { label = {below:\tiny F} },
    Q/.style = { label = {below:\tiny Q} },
    B/.style = { label = {below:\tiny B} },
    V/.style = { label = {below:\tiny V} },
    W/.style = { label = {below:\tiny W} },
}

\newcommand{\outpoint}[3]{
    \framebox{
        \texttt{\hash{#1}#2\color{black!60}:#3}
    }
}
\newcommand{\txout}[3]{
    \framebox{\parbox{10em}{
        #1 BTC\\
        \texttt{\hash{#2}#3}
    }}
}
\newcommand{\hash}[9]{\texttt{\color{black!60}#1\color{black!55}#2\color{black!50}#3\color{black!45}#4\color{black!35}#5\color{black!25}#6\color{black!15}#7\color{black!10}#8\color{black!5}#9}}
\newcommand{\witstack}[4]{
    \framebox{\parbox{10em}{
        \texttt{\hash{#1}#2}
    }}
    \framebox{\parbox[t][8em]{10em}{\texttt{
        ~\\
        \alert{#3}\\
        #4
    }}}
}

\setlength{\fboxsep}{1ex}
\begin{document}
\frame{ \maketitle }

\frame
{
    \frametitle{Issues with Bitcoin Script}

    \begin{itemize}
    \item Difficult to argue \alert{correctness} (or other properties)
    \item Difficult to argue \alert{security} (or malleability freeness)
    \item Difficult to estimate satisfaction cost
    \item Difficult to determine which signatures are needed
    \item Difficult to assemble a witness, even given signatures
    \end{itemize}
}

\frame
{
    \frametitle{Issues with Bitcoin Script}
    \begin{itemize}
    \item Not \alert{interoperable} between wallet implementations
    \item Not \alert{composeable} within wallets
    \end{itemize}
}

\frame
{
    \frametitle{Miniscript}

    \begin{itemize}
    \item Idea: create script templates for signature checks, hash-locks and time-locks
    \item Idea: create \alert{composable} script templates for AND, OR and thresholds
    \end{itemize}
}

\frame
{
    \frametitle{Miniscript}
    % todo figure out this \indent black magic
    \begin{minipage}[c]{0.5\textwidth}
        \texttt{2 pk$_1$ pk$_2$ pk$_3$ 3 CHECKMULTISIG\\
        \alert{IFDUP NOTIF}\\
        \indent ~~~~pk\textsubscript{emergency} CHECKSIGVERIFY\\
        \indent ~~~~1000 CSV\\
        \alert{ENDIF}}
    \end{minipage}
    \begin{minipage}[c]{0.45\textwidth}

    \begin{tikzpicture}[
        level 1/.style = {sibling distance=8em},
        level 2/.style = {sibling distance=8em},
    ]
        \node[comb,B] {OR\textsubscript{c}}
            child { node[term,B] {thresh\_m(2,pk$_1$,pk$_2$,pk$_3$)} }
            child { node[comb,B] {AND\textsubscript{v}}
                child { node[term,V] {vc:pk\textsubscript{emergency}} }
                child { node[term,B] {after(1000)} }
            };
    \end{tikzpicture}
    \end{minipage}
}

\frame
{
    \frametitle{Miniscript}
    % todo figure out this \indent black magic
    \begin{minipage}[c]{0.5\textwidth}
        \texttt{2 pk$_1$ pk$_2$ pk$_3$ 3 CHECKMULTISIG\\
        \alert{IFDUP NOTIF}\\
        \indent ~~~~pk\textsubscript{emergency} CHECKSIGVERIFY\\
        \indent ~~~~1000 CSV\\
        \alert{ENDIF}}
    \end{minipage}
    \begin{minipage}[c]{0.45\textwidth}

    \begin{tikzpicture}[
        level 1/.style = {sibling distance=8em},
        level 2/.style = {sibling distance=8em},
    ]
        \node[comb] {OR}
            child { node[term] {thresh\_m(2,pk$_1$,pk$_2$,pk$_3$)} }
            child { node[comb] {AND}
                child { node[term] {pk\textsubscript{emergency}} }
                child { node[term] {after(1000)} }
            };
    \end{tikzpicture}
    \end{minipage}
}

\frame
{
    \frametitle{Script and Miniscript}

    \begin{itemize}
    \item In a technical sense, Miniscript is a subset of Script.
    \item In a non-technical sense, Miniscript works in a \alert{different paradigm} than Script
    \item Miniscript describes \alert{conditions to satisfy}, not \alert{instructions to execute}
    \end{itemize}
}

\frame
{
    \frametitle{Miniscript}
    % todo figure out this \indent black magic
    \begin{minipage}[c]{0.5\textwidth}
        [some totally different language]
    \end{minipage}
    \begin{minipage}[c]{0.45\textwidth}

    \begin{tikzpicture}[
        level 1/.style = {sibling distance=8em},
        level 2/.style = {sibling distance=8em},
    ]
        \node[comb] {OR}
            child { node[term] {thresh\_m(2,pk$_1$,pk$_2$,pk$_3$)} }
            child { node[comb] {AND}
                child { node[term] {pk\textsubscript{emergency}} }
                child { node[term] {after(1000)} }
            };
    \end{tikzpicture}
    \end{minipage}
}

\frame
{
    \frametitle{Future Work}

    \begin{itemize}
    \item Further Integration with PSBT
    \item Library development (\texttt{rust-bitcoin}, \texttt{bdk})
    \item Taproot support!
    \item Connections to other languages (Script+\texttt{CTV}, Simplicity)
    \end{itemize}
}

%% end
\frame
{
    \frametitle{Thank You}
    \begin{center}
    Andrew Poelstra\\
    \texttt{miniscript@wpsoftware.net}\\~\\~\\
    \texttt{\huge https://bitcoin.sipa.be/miniscript}
    \end{center}
}

\end{document}