scripts/env

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