#!/usr/bin/env bash

# This script will update freeview to the current dev version. FREESURFER_HOME must be set.
# For ease (but definitely not efficiency), the whole dev release is downloaded to a
# temporary dir, and the necessary files are copied to the target distribution.
#
# NOTE: this script should NOT be installed in the freesurfer release since, by design, it will
# always be outdated. Instead, it should be copied to:
#
#       https://surfer.nmr.mgh.harvard.edu/pub/dist/freesurfer/installers/fv
#
# where users will always be able to access and run the most up-to-date installer via:
#       
#       bash <(curl -s https://surfer.nmr.mgh.harvard.edu/pub/dist/freesurfer/installers/fv)
#

set -e

# utility functions
function cleanup { if [ -e "$tmpdir" ]; then rm -rf $tmpdir; fi }
function errexit { cleanup; echo "ERROR: $1"; exit 1; }
function replace { for path in "$@"; do rm -rf $FREESURFER_HOME/$path; mv freesurfer/$path $FREESURFER_HOME/$path; done }

# parse arguments
for arg in "$@"; do
case $arg in
    -f|--force) force=true ;;
    -h|--help) echo "Updates freeview. Use the -f flag to force the installation."; exit ;;
    *) errexit "unknown option $arg" ;;
esac
done

# cleanup temporary directory upon exit/kill
trap cleanup EXIT SIGINT SIGTERM

# check the FS install
if [ -z "$FREESURFER_HOME" ]; then errexit "FREESURFER_HOME has not been defined"; fi
if [ ! -e "$FREESURFER_HOME/lib" ]; then errexit "directory $FREESURFER_HOME/lib does not exist - does FREESURFER_HOME point to a valid FreeSurfer install?"; fi
if [ ! -e "$FREESURFER_HOME/bin" ]; then errexit "directory $FREESURFER_HOME/bin does not exist - does FREESURFER_HOME point to a valid FreeSurfer install?"; fi

# ask before installing
if [ ! "$force" = true ]; then
    echo "This will update the freeview version installed in $FREESURFER_HOME"
    read -p "Are you sure you want to continue? [Y/n] " -n 1 -r
    echo
    if [[ ! $REPLY =~ ^[Yy]$ ]]; then exit; fi
fi

# operating system
system="$(uname -s)"

# OS independent way to create a temporary directory
tmpdir="$(mktemp -d 2>/dev/null || mktemp -d -t 'fstmpdir')"
cd $tmpdir

# download link for given OS
if [ "$system" == "Linux" ]; then
    link="https://surfer.nmr.mgh.harvard.edu/pub/dist/freesurfer/dev/freesurfer-linux-centos6_x86_64-dev.tar.gz"
elif [ "$system" == "Darwin" ]; then
    link="https://surfer.nmr.mgh.harvard.edu/pub/dist/freesurfer/dev/freesurfer-darwin-OSX-ElCapitan-dev.tar.gz"
else
    errexit "OS $system is not supported"
fi

echo "Downloading FreeSurfer..."
curl -# $link -o freesurfer.tar.gz

echo "Uncompressing the download (this might take a while)..."
tar -xzf freesurfer.tar.gz

echo "Updating..."
if [ "$system" == "Linux" ]; then
    replace bin/freeview bin/qt.conf lib/qt
    rm -f $FREESURFER_HOME/bin/freeview.bin  # old, unnecessary file
elif [ "$system" == "Darwin" ]; then
    replace bin/freeview Freeview.app
fi

echo "Freeview update complete!"