#!/bin/sh
set -e -f ${DRY_RUN:+-n} -u
tool=${0%/*}
. "$tool"/lib/functions.sh
. "$tool"/etc/vm.sh

rule_help () {
	cat >&2 <<-EOF
		DESCRIPTION: ce script regroupe des fonctions utilitaires
		             pour gérer la VM _depuis_ une machine distante ;
		             il sert à la fois d'outil et de documentation.
		             Voir \`$tool/vm_host'   pour les utilitaires côté machine hôte.
		             Voir \`$tool/vm_hosted' pour les utilitaires côté VM hébergée.
		SYNTAX: $0 \$RULE \${RULE}_SYNTAX
		RULES:
		$(sed -ne 's/^rule_\([^_][^ ]*\) () {\( *#.*\|\)/\t\1\2/p' "$tool"/vm.sh "$0")
		ENVIRONMENT:
		  TRACE # affiche les commandes avant leur exécution
		$(sed -ne 's/^readonly \([^ ][^ =]*\).*}\( *#.*\|\)$/\t$\1\2/p' "$tool"/vm.sh "$0")
		EOF
 }

rule_git_config () {
	(
	cd "$tool"
	git config remote.host.url >/dev/null ||
	git remote add host $vm_host:tool/vm
	git config --replace remote.host HEAD:refs/heads/origin
	git config remote.$vm.url >/dev/null ||
	git remote add vm root@$vm_fqdn:tool/vm
	git config --replace remote.$vm HEAD:refs/heads/origin
	)
 }
rule_git_push () { # SYNTAX: {host|vm} $git_commit_options
	local remote=${1#remote=}; shift
	git add . &&
	git commit -a -C HEAD "$@" &&
	GIT_SSH=./vm_ssh git push -v -f "$remote"
 }

rule_ssh () {
	"$tool"/vm_ssh $vm_fqdn "$@"
 }
rule__ssh_known_hosts_update () {
	"$tool"/vm_ssh $vm_fqdn "$@" \
	 -o StrictHostKeyChecking=no \
	 -o CheckHostIP=no \
	 -o HashKnownHosts=no \
	 whoami
 }
rule_disk_key_send () {
	gpg --decrypt var/lib/luks/$vm_fqdn.key.gpg |
	"$tool"/vm_ssh root@$vm_fqdn "$@" \
	 -o CheckHostIP=no \
	 -o HostKeyAlias=init.$vm_fqdn \
	 tee /lib/cryptsetup/passfifo \>/dev/null
 }
rule_disk_key_backup () {
	for part in root var home
	 do
		mkdir -p var/lib/luks
		rule_ssh -l root ' \
			tmp=$(mktemp)
			cryptsetup luksHeaderBackup \
			 /dev/$vm_lvm_vg/${vm_lvm_lv}_${part} \
			 --header-backup-file "$tmp" \
			cat "$tmp"
			shred --remove "$tmp"
		 ' |
		gpg --encrypt --recipient $USER@ \
		 -o var/lib/luks/${vm_lvm_lv}_${part}.luks.gpg
	 done
 }

rule=${1:-help}
${1+shift}
case $rule in
 (help);;
 (*)
	test ! "$(hostname --fqdn)" = "$vm_fqdn"
	test ! "$(hostname --fqdn)" = "$vm_host"
	set -x
	;;
 esac
rule_$rule "$@"