focus-emacs-frame

#!/bin/bash
#
# Uses wmctrl to focus an emacs frame, preferring one on the current
# desktop if it exists.  Do not call this directly - instead use
# quick-emacs.

LOGFILE=$HOME/.log/focus-emacs-frame.log
me=`basename $0`

_dlog    () { echo "`date` $*" >> "$LOGFILE" 2>&1;                  }
debug    () { _dlog "$*";                                           }
progress () { _dlog "$*";        echo     "$me: $*";                }
warn     () { _dlog "$*";        echo >&2 "$me: $*";                }
error    () { _dlog "ERROR: $*"; echo >&2 "$me: ERROR: $*";         }
fatal    () { _dlog "FATAL: $*"; echo >&2 "$me: FATAL: $*"; exit 1; }

check_prereqs () {
    if [ -z "$DISPLAY" ]; then
        fatal "DISPLAY environment variable was not set"
    fi

    if ! which wmctrl >/dev/null 2>&1; then
        fatal "wmctrl not found; aborting."
    fi

    if ! which xdotool >/dev/null 2>&1; then
        fatal "xdotool not found; aborting."
    fi
}

get_desktop_for_window () {
    win_id="$1"
    #xdotool get_desktop_for_window $win_id
    wmctrl -lpx | grep "$win_id" | awk '{print $2}'
}

main () {
    host="`hostname`"
    host="${host%%.*}"

    check_prereqs
    if ! target_window_id=$( emacs-window-id ); then
        fatal "emacs-window-id failed to get target window id"
    fi

    debug "Window name at start: $(current-window-name)"

    if ! desktop=$( get_desktop_for_window $target_window_id ); then
        fatal "Failed to get desktop number for emacs window $target_window_id"
    fi

    if [ "$desktop" = -1 ]; then
        debug "Window is sticky across all desktops"
    else
        if ! xdotool set_desktop $desktop; then
            fatal "Failed to switch to desktop $desktop"
        fi
    fi

    sleep=0.1
    while [ $( echo "$sleep < 30" | bc ) = 1 ]; do
        #xdotool windowfocus --sync $target_window_id windowraise "$target_window_id"
        debug "Switching to $target_window_id"
        wmctrl -ia "$target_window_id"

        debug "sleeping $sleep"
        sleep $sleep
        sleep=$( echo "$sleep * 2" | bc )

        current_window_id="$(current-window-id)"
        debug "Current window id is $current_window_id"
        if [ "$current_window_id" = "$target_window_id" ]; then
            debug "Successfully focused $target_window_id"
            debug "Window name at end: $(current-window-name)"
            exit 0
        fi
    done

    fatal "Failed to focus emacs window $target_window_id"
}

main "$@"