#!/usr/bin/env bash

# Functions

VERBOSE=0
MAXSTEP=0

binary_exists() {
    if ! command -v $1 &> /dev/null
    then
        cat <<EOF
Command "$1" could not be found in \$PATH.
Hint: $2
EOF
        exit 1
    fi
}

help() {
    cat <<EOF >&2
Usage: $0 [OPTIONS] file.ept
Options:
        -s <node_name>       Simulate node <node_name>
        -t                   Simulate in text mode
        -g                   Simulate in graphical mode (hepts)
        -m <maximum>         Stop after <maximum> steps in text mode
        -c                   Check for required tools and terminate
        -v                   Print internal information
EOF
}

info() {
    if [ $VERBOSE -ne 0 ]; then echo $1; fi
}

warn() {
    echo -e "\e[93m$1\e[0m" >&2
}

die() {
    echo -e "\e[31m$1\e[0m" >&2
    exit 1
}

cmd() {
    if [ $VERBOSE -ne 0 ]; then echo $1; fi
    command $1
}

# Entry point

VERBOSE=0
if ! command -v hepts &> /dev/null
then
    GRAPHICAL=0
else
    GRAPHICAL=1
fi

NODES=""

while getopts "cvs:htgm:" OPT
do
    case "${OPT}" in
        v)
            VERBOSE=1
            ;;
        s)
            NODES="${NODES} ${OPTARG}"
            ;;
        t)
            GRAPHICAL=0
            ;;
        g)
            GRAPHICAL=1
            ;;
        h)
            help
            exit 0
            ;;
        c)
            binary_exists "realpath" "brew install coreutils"
            binary_exists "gcc" "use the package manager of your Linux distro"
            binary_exists "heptc" "opam install heptagon"
            binary_exists "hepts" "opam install lablgtk heptagon"
            echo "All tools seem to be available, $0 ready to run simulations"
            exit 0
            ;;
        m)
            MAXSTEP=$(expr ${OPTARG})
            ;;
        ?)
            help
            ;;
    esac
done
shift $((OPTIND-1))

if [ $# -lt 1 ]
then
    help
    exit 1
fi

if [ $GRAPHICAL -eq 1 ]
then
    binary_exists "hepts" "opam install lablgtk heptagon"
fi
binary_exists "heptc" "opam install heptagon"
binary_exists "gcc" "use the package manager of your Linux distro"
binary_exists "realpath" "brew install coreutils"

CDIR=`pwd`
FILE=$1
TMPDIR=`mktemp -d`
BASENAME=`basename $1 .ept`
MOD="$(tr '[:lower:]' '[:upper:]' <<< ${BASENAME:0:1})${BASENAME:1}"
BIN=$BASENAME.bin

info "Entering temporary dir $TMPDIR"

cp $FILE $TMPDIR
cd $TMPDIR

if [ "$NODES" = "" ]; then
    warn "No node specified. In $FILE, there is:"
    egrep -oh '(node|fun) *(\w+)' "$FILE"
fi

for NODE in $NODES
do
    info "Simulating node $NODE in $FILE"

    if [ $GRAPHICAL -eq 1 ]
    then
        cmd "heptc -target c -s $NODE -hepts $FILE"
    else
        cmd "heptc -target c -s $NODE $FILE"
    fi
    if [ $? -ne 0 ]; then exit 1; fi

    DIRN=${BASENAME//-/lex45_}_c
    [ -d ${DIRN} ] || die "Could not find directory ${DIRN}"

    cd ${DIRN}
    cmd "gcc -I `heptc -where`/c *.c -o ../$BIN"
    if [ $? -ne 0 ]
    then
        die "Could not compile the generated C code in $TMPDIR"
    fi
    cd ..

    info "Running simulation of $NODE"

    if [ $GRAPHICAL -eq 1 ]
    then
        cmd "hepts -mod $MOD -node $NODE -exec "`realpath $TMPDIR/$BIN`""
    else
        cmd "`realpath $TMPDIR/$BIN` ${MAXSTEP}"
    fi
    if [ $? -ne 0 ]; then die "Could not simulate node $NODE"; fi
done
info "Finished simulation"