scripts/env

   1 #!/usr/bin/env bash
   2 BASEDIR="$PWD"
   3 ENVDIR="$PWD/env"
   4
   5 usage() {
   6         cat <<EOF
   7 Usage: $0 [options] <command> [arguments]
   8 Commands:
   9         help              This help text
  10         list              List environments
  11         clear             Delete all environment and revert to flat config/files
  12         new <name>        Create a new environment
  13         switch <name>     Switch to a different environment
  14         delete <name>     Delete an environment
  15         rename <newname>  Rename the current environment
  16         diff              Show differences between current state and environment
  17         save              Save your changes to the environment
  18         revert            Revert your changes since last save
  19
  20 Options:
  21
  22 EOF
  23         exit ${1:-1}
  24 }
  25
  26 error() {
  27         echo "$0: $*"
  28         exit 1
  29 }
  30
  31 ask_bool() {
  32         local DEFAULT="$1"; shift
  33         local def defstr val
  34         case "$DEFAULT" in
  35                 1) def=0; defstr="Y/n";;
  36                 0) def=1; defstr="y/N";;
  37                 *) def=;  defstr="y/n";;
  38         esac
  39         while [ -z "$val" ]; do
  40                 local VAL
  41
  42                 echo -n "$* ($defstr): "
  43                 read VAL
  44                 case "$VAL" in
  45                         y*|Y*) val=0;;
  46                         n*|N*) val=1;;
  47                         *) val="$def";;
  48                 esac
  49         done
  50         return "$val"
  51 }
  52
  53 env_init() {
  54         local CREATE="$1"
  55         if [ -z "$CREATE" ]; then
  56                 [ -d "$ENVDIR" ] || exit 0
  57         fi
  58         [ -x "$(which git 2>/dev/null)" ] || error "Git is not installed"
  59         mkdir -p "$ENVDIR" || error "Failed to create the environment directory"
  60         cd "$ENVDIR" || error "Failed to switch to the environment directory"
  61         [ -d .git ] || {
  62                 git init &&
  63                 touch .config &&
  64                 mkdir files &&
  65                 git-add . &&
  66                 git-commit -q -m "Initial import"
  67         } || {
  68                 rm -rf .git
  69                 error "Failed to initialize the environment directory"
  70         }
  71 }
  72
  73 env_sync_data() {
  74         [ \! -L "$BASEDIR/.config" -a -f "$BASEDIR/.config" ] && mv "$BASEDIR/.config" "$ENVDIR"
  75         git-add .
  76         git-add -u
  77 }
  78
  79 env_sync() {
  80         local STR="$1"
  81         env_sync_data
  82         git-commit -m "${STR:-Update} at $(date)"
  83 }
  84
  85 env_link_config() {
  86         rm -f "$BASEDIR/.config"
  87         ln -s env/.config "$BASEDIR/.config"
  88         mkdir -p "$ENVDIR/files"
  89         [ -L "$BASEDIR/files" ] || ln -s env/files "$BASEDIR/files"
  90 }
  91
  92 env_do_reset() {
  93         git-reset --hard HEAD
  94         git-clean -d -f
  95 }
  96
  97 env_list() {
  98         env_init
  99         git-branch | grep -vE '^. master$'
 100 }
 101
 102 env_diff() {
 103         env_init
 104         env_sync_data
 105         git-diff --cached
 106 }
 107
 108 env_save() {
 109         env_init
 110         env_sync
 111         env_link_config
 112 }
 113
 114 env_revert() {
 115         env_init
 116         env_do_reset
 117         env_link_config
 118 }
 119
 120 env_ask_sync() {
 121         LINES="$(env_diff | wc -l)" # implies env_init
 122         [ "$LINES" -gt 0 ] && {
 123                 if ask_bool 1 "Do you want to save your changes"; then
 124                         env_sync
 125                 else
 126                         env_sync_data
 127                         env_do_reset
 128                 fi
 129         }
 130 }
 131
 132 env_clear() {
 133         env_init
 134         [ -L "$BASEDIR/.config" ] && rm -f "$BASEDIR/.config"
 135         [ -L "$BASEDIR/files" ] && rm -f "$BASEDIR/files"
 136         [ -f "$ENVDIR/.config" ] || ( cd "$ENVDIR/files" && find | grep -vE '^\.$' > /dev/null )
 137         env_sync_data
 138         if ask_bool 1 "Do you want to keep your current config and files"; then
 139                 mkdir -p "$BASEDIR/files"
 140                 cp -a "$ENVDIR/files/*" "$BASEDIR/files" 2>/dev/null >/dev/null
 141                 cp "$ENVDIR/.config" "$BASEDIR/"
 142         else
 143                 rm -rf "$BASEDIR/files" "$BASEDIR/.config"
 144         fi
 145         cd "$BASEDIR"
 146         rm -rf "$ENVDIR"
 147 }
 148
 149 env_delete() {
 150         local name="${1##*/}"
 151         [ -z "$name" ] && usage
 152         [ -f "$envdir/.git/refs/heads/$name" ] || error "environment '$name' not found"
 153         branch="$(git-branch | grep '^\* ' | awk '{print $2}')"
 154         [ "$name" = "branch" ] && error "cannot delete the currently selected environment"
 155         git-branch -D "$name"
 156 }
 157
 158 env_switch() {
 159         local name="${1##*/}"
 160         [ -z "$name" ] && usage
 161         [ -f "$ENVDIR/.git/refs/heads/$name" ] || error "environment '$name' not found"
 162
 163         env_init
 164         env_ask_sync
 165         git-checkout "$name"
 166         env_link_config
 167 }
 168
 169 env_rename() {
 170         local NAME="${1##*/}"
 171         env_init
 172         git-branch -m "$NAME"
 173 }
 174
 175 env_new() {
 176         local NAME="$1"
 177         local branch
 178         local from="master"
 179
 180         [ -z "$NAME" ] && usage
 181         env_init 1
 182
 183         branch="$(git-branch | grep '^\* ' | awk '{print $2}')"
 184         if [ -n "$branch" -a "$branch" != "master" ]; then
 185                 env_ask_sync
 186                 if ask_bool 0 "Do you want to clone the current environment?"; then
 187                         from="$branch"
 188                 fi
 189                 rm -f "$BASEDIR/.config" "$BASEDIR/files"
 190         fi
 191         git-checkout -b "$1" "$from"
 192         if [ -f "$BASEDIR/.config" -o -d "$BASEDIR/files" ]; then
 193                 if ask_bool 1 "Do you want to keep your current config and files?"; then
 194                         [ -d "$BASEDIR/files" -a \! -L "$BASEDIR/files" ] && {
 195                                 mv "$BASEDIR/files/"* "$ENVDIR/" 2>/dev/null
 196                                 rmdir "$BASEDIR/files"
 197                         }
 198                         env_sync
 199                 else
 200                         rm -rf "$BASEDIR/.config" "$BASEDIR/files"
 201                 fi
 202         fi
 203         env_link_config
 204 }
 205
 206 COMMAND="$1"; shift
 207 case "$COMMAND" in
 208         help) usage 0;;
 209         new) env_new "$@";;
 210         list) env_list "$@";;
 211         clear) env_clear "$@";;
 212         switch) env_switch "$@";;
 213         delete) env_delete "$@";;
 214         rename) env_rename "$@";;
 215         diff) env_diff "$@";;
 216         save) env_save "$@";;
 217         revert) env_revert "$@";;
 218         *) usage;;
 219 esac