#!/usr/bin/env bash
set -x
set -e

# Ensure the directory for LAST_DEPENDENCIES_HASH exists
mkdir -p /var/lib/zulip

SOURCES_FILE=/etc/apt/sources.list.d/zulip_debathena.list
STAMP_FILE=/etc/apt/sources.list.d/zulip_debathena.list.apt-update-in-progress

ZULIP_SCRIPTS="$(dirname "$(dirname "$0")")"
DEPENDENCIES_HASH=$(sha1sum "$ZULIP_SCRIPTS/setup/"*.asc "$0")
DEPENDENCIES_HASH_FILE="/var/lib/zulip/setup-repositories-state-debathena"
# Ensure that DEPENDENCIES_HASH_FILE exists before hashing it.
touch "$DEPENDENCIES_HASH_FILE"
LAST_DEPENDENCIES_HASH="$(cat "$DEPENDENCIES_HASH_FILE")"

# First, we only do anything in setup-apt-repo if any of its inputs
# (apt keys, code, etc.)  changed.
if [ "$DEPENDENCIES_HASH" = "$LAST_DEPENDENCIES_HASH" ]; then
    exit 0
fi

# Ensure that the sources file exists
touch "$SOURCES_FILE"

# Hash it to check if the sources file is changed by the script later.
zulip_source_hash=$(sha1sum "$SOURCES_FILE")

apt-get install -y lsb-release apt-transport-https gnupg

SCRIPTS_PATH="$(dirname "$(dirname "$0")")"

release=$(lsb_release -sc)
if [ "$release" = "xenial" ]; then
    apt-key add "$SCRIPTS_PATH"/setup/debathena-archive.asc
    cat >$SOURCES_FILE <<EOF
    deb http://debathena.mit.edu/apt $release debathena debathena-config
    deb-src http://debathena.mit.edu/apt $release debathena debathena-config
EOF
else
    echo "Unsupported release $release."
    exit 1
fi

# Copied blindly from scripts/lib/setup-apt-repo
if [ "$zulip_source_hash" = "$(sha1sum "$SOURCES_FILE")" ] && ! [ -e "$STAMP_FILE" ]; then
    echo "zulip.list file did not change; skipping apt-get update"
else
    # We create this stamp file to ensure `apt-get update` will be run
    # the next time this script is invoked, and each time after, until
    # `apt-get update` finishes successfully.
    touch "$STAMP_FILE"
    apt-get update && rm -f "$STAMP_FILE"
fi

echo "$DEPENDENCIES_HASH" > "$DEPENDENCIES_HASH_FILE"