refactor upgrade script

UPDATE.sh

@@ -1,32 +1,91 @@
-#!/bin/bash
-distro=$1
-if [ -z ${distro+x} ]; then 
-    distro='master'
+#!/usr/bin/env bash
+
+progname=$(basename $0)
+
+tmpd=$(mktemp -d)
+trap "rm -rf $tmpd" EXIT
+
+set -e
+
+err() {
+  echo "$progname: ""$@" >&2
+}
+
+usage() {
+  echo "usage: $progname: -b <git branch> -d </full/path/to/shinobi>"
+  echo ""
+  echo "-b   dev|master      the branch of Shinobi you want to use"
+  echo "-d   /opt/Shinobi    the full path to your Shinobi checkout"
+  echo "-h                   show help"
+}
+
+if [[ $# -eq 0 ]]; then
+  usage >&2
+  exit 99
 fi
-rm -rf $distro master_temp
-wget https://github.com/ShinobiCCTV/Shinobi/tarball/$distro
-mkdir master_temp
-tar -xzf $distro -C master_temp --strip-components=1
+
+while getopts hd:b: opt; do
+  case $opt in
+    b)
+      case $OPTARG in
+        dev|master)
+          distro=$OPTARG
+          ;;
+        *)
+          err "branch must be dev or master"
+          exit 1
+          ;;
+      esac
+      ;;
+    d)
+      if [[ ! -w $OPTARG ]]; then
+        err "$OPTARG is not writable"
+        exit 2
+      fi
+      shinobi=$OPTARG
+      ;;
+    h)
+      usage
+      exit 0
+      ;;
+    *)
+      usage
+      exit 10
+      ;;
+  esac
+done
+shift $((OPTIND-1))
+
+if [[ -z $distro ]]; then
+  err "-b <branch> is required"
+  usage >&2
+  exit 99
+fi
+
+if [[ -z $shinobi ]]; then
+  err "-d </full/path/to/shinobi/checkout> is required"
+  usage >&2
+  exit 99
+fi
+
+# download  source
+wget -O $tmpd/$distro https://github.com/ShinobiCCTV/Shinobi/tarball/$distro
+
+# stop existing processes
+cd $shinobi
 pm2 stop camera.js
 pm2 stop cron.js
 pm2 kill
-mv master_temp/UPDATE.sh UPDATE.sh
-chmod +x UPDATE.sh
-sed -i 's/\r//' UPDATE.sh
-mv master_temp/languages languages
-mv master_temp/definitions definitions
-mv master_temp/web web
-mv master_temp/LICENSE LICENSE
-mv master_temp/COPYING COPYING
-mv master_temp/package.json package.json
-mv master_temp/camera.js camera.js
-mv master_temp/cron.js cron.js
-mv master_temp/plugins/motion/shinobi-motion.js plugins/motion/shinobi-motion.js
-mv master_temp/plugins/opencv/shinobi-opencv.js plugins/motion/shinobi-opencv.js
+
+# unpack new files to shinobi directory
+tar -xzf $tmpd/$distro --strip-components=1
+
+# update nodejs modules and start shinobi processes
 npm install
-rm -rf $distro master_temp
 pm2 start camera.js
 pm2 start cron.js
-if [ ! -f plugins/motion/conf.json ]; then
-    pm2 start plugins/motion/shinobi-motion.js
-fi
+if [[ -f plugins/motion/conf.json ]]; then
+  pm2 start plugins/motion/shinobi-motion.js
+fi
+
+exit 0