#!/bin/sh
# postinst script for signalfx-agent
#
# see: dh_installdeb(1)

set -e

# summary of how this script can be called:
#        * <postinst> `configure' <most-recently-configured-version>
#        * <old-postinst> `abort-upgrade' <new version>
#        * <conflictor's-postinst> `abort-remove' `in-favour' <package>
#          <new-version>
#        * <postinst> `abort-remove'
#        * <deconfigured's-postinst> `abort-deconfigure' `in-favour'
#          <failed-install-package> <version> `removing'
#          <conflicting-package> <version>
# for details, see https://www.debian.org/doc/debian-policy/ or
# the debian-policy package

case "$1" in
    configure)
        bundle_dir=/usr/lib/signalfx-agent
        getent passwd signalfx-agent >/dev/null || \
          useradd --system --home-dir $bundle_dir --no-create-home --shell /sbin/nologin signalfx-agent
        setcap CAP_SYS_PTRACE,CAP_DAC_READ_SEARCH=+eip $bundle_dir/bin/signalfx-agent
        
        # Get the binaries' interpreter patched properly
        ${bundle_dir}/bin/patch-interpreter ${bundle_dir}

        echo "The SignalFx agent has been successfully installed."
        echo "If you do not already have a access token configured, please add it to /etc/signalfx/agent.yaml and then start the agent."
    ;;

    abort-upgrade|abort-remove|abort-deconfigure)
    ;;

    *)
        echo "postinst called with unknown argument \`$1'" >&2
        exit 1
    ;;
esac

# All of the autogenerated sections are copied and hardcoded here so that we
# can conditionalize the use of deb-systemd-helper.

if command -v deb-systemd-helper; then
  deb-systemd-helper unmask signalfx-agent.service >/dev/null || true

  # was-enabled defaults to true, so new installations run enable.
  if deb-systemd-helper --quiet was-enabled signalfx-agent.service; then
          # Enables the unit on first installation, creates new
          # symlinks on upgrades if the unit file has changed.
          deb-systemd-helper enable signalfx-agent.service >/dev/null || true
  else
          # Update the statefile to add new symlinks (if any), which need to be
          # cleaned up on purge. Also remove old symlinks.
          deb-systemd-helper update-state signalfx-agent.service >/dev/null || true
  fi
fi

if [ "$1" = "configure" ] || [ "$1" = "abort-upgrade" ]; then
        # In case this system is running systemd, we need to ensure that all
        # necessary tmpfiles (if any) are created before starting.
        if [ -d /run/systemd/system ] ; then
                systemd-tmpfiles --create /usr/lib/tmpfiles.d/signalfx-agent.conf >/dev/null || true
                if command -v update-rc.d && [ -e "/etc/init.d/signalfx-agent" ]; then
                    rm -f /etc/init.d/signalfx-agent
                    update-rc.d -f signalfx-agent remove >/dev/null || exit $?
                fi
        fi
fi

if [ "$1" = "configure" ] || [ "$1" = "abort-upgrade" ]; then
  if [ -x "/etc/init.d/signalfx-agent" ]; then
    if command -v update-rc.d; then
      update-rc.d signalfx-agent defaults >/dev/null || exit $?
    fi
  fi
fi

exit 0