etmux

#! /bin/sh

VERSION=0.3

version() {
    echo "$0 version $VERSION"
}

usage() {
    cat << EOF

usage: $0 [options] [session name]

options:
    -h    Show this message
    -v    Output version information
    -V    Verbose

tmux options:
    -d    Detach other clients when connecting to session, the same as tmux's
            attach-session -d option
    -S    Specify a socket file to use with tmux, the same as tmux's -S option

EOF
}

# DEFAULTS
detach=
socket=
help=
version=
verbose=false

# options
short="dS:cvVh"
long="detach,socket:,version,help"
getopt -T > /dev/null 2> /dev/null
if [ $? -eq 4 ]; then
  # the getopt supports long arguments
  opts=`getopt -o $short --long $long -n "$0" -- "$@"`
else
  # fall back to basic getopt
  opts=`getopt $short "$@"`
fi
if [ $? != 0 ] ; then echo "getopt failed, terminating" >&2 ; exit 1 ; fi
eval set -- "$opts"

while true
  do case "$1" in
      d|-d|--detach)  detach="-d" ; shift ;;
      S|-S|--socket)
        # socket has a required argument
        socket="$2"
        socket_flag="-S \"$2\""
        shift 2 ;;
      v|-v|--version)  version=true; shift ;;
      h|-h|--help)  help=true; shift ;;
      V|-V|--verbose)  verbose=true; shift ;;
      --) shift ; break ;;
  esac
done

if [ $help ]; then
  version
  usage
  exit
fi
if [ $version ]; then
  version
  exit
fi

# the first argument passed in will be our session name
session=$1

# make sure we have a session name
if [ -z "$session" ]; then
  session="${PWD##*/}"
fi

#default ETMUX_PATH
if [ -z "$ETMUX_PATH" ]; then
  ETMUX_PATH=~/.etmux-sessions
fi
#default ETMUX_SCRIPT_NAME
if [ -z "$ETMUX_SCRIPT_NAME" ]; then
  ETMUX_SCRIPT_NAME=.etmux.sh
fi

if [ -z "$socket" ] && [ ! -z "$TMUX" ]; then
  # they haven't specified their own socket, so we get the location of the
  # current one, to make sure all commands use the right socket
  socket=`echo $TMUX | sed "s/^\(.*\),[0-9]\{1,\},[0-9]\{1,\}$/\1/"`
  socket_flag="-S \"$socket\""
fi

# go ahead and create join here, since both code paths use it
if [ -z "$TMUX" ]; then
    $verbose && echo "not in tmux, will attach"
    join_cmd="tmux $socket_flag attach-session $detach -t \"$session\""
else
    $verbose && echo "in tmux now, so will switch"
    if [ ! -z "$detach" ]; then
        detach="detach-client -s $session \\;"
    fi
    join_cmd="tmux $socket_flag $detach switch-client -t \"$session\""
fi

checkForSessionScript() {
  # split the ETMUX_PATH string
  old_ifs=$IFS; IFS=':'; paths=$ETMUX_PATH
  # loop through each dir in path to see if we have a match
  for x in $paths; do
      $verbose && echo "looking in $x" >&2

      if [ -d "$x/$session" ]; then
          $verbose && echo "found directory: $x/$session" >&2
          echo "$x/$session"
          break
      elif [ -x "$x/$session" ]; then
          $verbose && echo "found script: $x/$session" >&2
          echo "$x/$session"
          break
      elif [ -f "$x/$session" ]; then
          echo "found \`$session\` in $x but it is not a directory or executable" >&2
          exit 1
      fi
  done
  IFS=$old_ifs
}

runSessionScript() {
    $verbose && echo "running $1" >&2

    if [ -d "$x/$session" ]; then
      cd $1
    fi

    # create custom script
    filename=`mktemp /tmp/etmux-session-XXXXXXX`
    echo "start() {\n\t$start_cmd\n}\n" >> $filename
    echo "join() {\n\t$join_cmd\n}\n" >> $filename
    if [ ! -z "$socket_flag" ]; then
        echo "alias tmux='tmux $socket_flag'" >> $filename
    fi

    if [ -d "$1" -a -x "$1/$ETMUX_SCRIPT_NAME" ]; then
      cat "$1/$ETMUX_SCRIPT_NAME" >> $filename
    elif [ ! -d "$1" -a -x "$1" ]; then
      cat "$1" >> $filename
    else
      echo "start && join" >> $filename
    fi

    $verbose && echo "created tmp script at $filename:" >&2
    $verbose && echo "---------------------------------" >&2
    $verbose && cat $filename >&2
    $verbose && echo "---------------------------------" >&2

    # run the custom script
    env socket="$socket" session="$session" sh $filename

    # remove custom script
    rm $filename

    # exit so we don't do anything else
    exit
}

# does the session exist already?
if [ -z "$socket" ]; then
    has=`tmux start-server \; list-sessions | sed -n -e "s/$session: [0-9]\{1,\} windows /\0/p"`
else
    has=`tmux -S "$socket" start-server \; list-sessions | sed -n -e "s/$session: [0-9]\{1,\} windows /\0/p"`
fi

if [ -z "$has" ]; then
    # session doesn't exist

    $verbose && echo "creating session '$session'"

    start_cmd="env TMUX= tmux $socket_flag new-session -d -s \"$session\""

    sessionScript=`checkForSessionScript`
    if [ "$?" -ne 0 ]; then
      exit
    fi

    if [ -z "$sessionScript" ]; then
        # no script, just start and join ourselves
        $verbose && echo "did not find matching project, starting in current dir"
        eval $start_cmd
        eval $join_cmd
    else
        runSessionScript $sessionScript
    fi
else
    # session exists

    $verbose && echo "joining session '$session'"
    eval $join_cmd
fi