auto-disper

#!/bin/sh
#
# Automatically select a display configuration based on connected devives
#
# Stefan Tomanek <stefan.tomanek@wertarbyte.de>
#
# requires disper, the command line display switcher:
# http://willem.engen.nl/projects/disper/
#
#
# How to use:
#
# Save your current display configuration and setup with
# auto-disper --save mobil
#
# Connect an additional display, configure your setup and save it
# auto-disper --save docked
#
# Now auto-disper can detect which hardware setup is active: # auto-disper
# mobile
# docked (detected)
#
# To automatically reload your setup, just append --change to the command line
#
# To alternate between the detected setup and a default one (such as your laptop
# screen, set DEFAULT_PROFILE below appropriately and use the --toggle command
# line option. This is useful to bind to a keyboard shortcut (via your desktop's
# global shortcuts bindings or similar).
#
# To manually load a profile, you can use the --load <profile> option.
#
# To prevent a profile from being loaded, place a script call "block" in its
# directory. The script is evaluated before the screen setup is inspected, and
# in case of it returning a value of 0 the profile is skipped. This can be used
# to query the status of a docking station you are about to leave.
#
# If no suitable profile can be identified, the current configuration is kept.
# To change this behaviour and switch to a fallback configuration, specify
# --default <profile>
#
# Another script called "postswitch "can be placed in the directory
# ~/.auto-disper as well as in all profile directories: The scripts are
# executed after a mode switch has taken place and can notify window managers
# or other applications about it.

DISPER=/usr/bin/disper
XRANDR=/usr/bin/xrandr
PROFILES=~/.auto-disper/

# 0: no change, 1: switch to detected, 2: toggle between detected and default
CHANGE_PROFILE=0
DEFAULT_PROFILE="laptop"
SAVE_PROFILE=""

blocked() {
    local PROFILE="$1"
    [ ! -x "$PROFILES/$PROFILE/block" ] && return 1

    "$PROFILES/$PROFILE/block"  "$PROFILE"
}

load() {
    local PROFILE="$1"
    if [ "$CHANGE_PROFILE" -ge 1 ]; then
        echo " -> loading profile $PROFILE"
        $DISPER -i < "$PROFILES/$PROFILE/config"
        #hack to add auto-rotate support (manual config):
        if [ -f "$PROFILES/$PROFILE/xrandr-orientation" ]; then
	    $XRANDR --orientation $(cat "$PROFILES/$PROFILE/xrandr-orientation")
	else
	    $XRANDR --orientation normal
	fi

        [ -x "$PROFILES/$PROFILE/postswitch" ] && \
            "$PROFILES/$PROFILE/postswitch" "$PROFILE"
        [ -x "$PROFILES/postswitch" ] && \
            "$PROFILES/postswitch" "$PROFILE"
    fi
}

# process parameters
OPTS=$(getopt -n auto-disper -o s:l:d:cth --long toggle,change,default:,save:,load:,help -- "$@")
if [ $? != 0 ] ; then echo "Terminating..." >&2 ; exit 1 ; fi
eval set -- "$OPTS"

while true; do
    case "$1" in
        -c|--change) CHANGE_PROFILE=1; shift ;;
        -d|--default) DEFAULT_PROFILE="$2"; shift 2 ;;
        -s|--save) SAVE_PROFILE="$2"; shift 2 ;;
        -l|--load) LOAD_PROFILE="$2"; shift 2 ;;
        -t|--toggle) CHANGE_PROFILE=2; shift ;;
        -h|--help) PRINT_HELP=1; shift ;;
        --) shift; break ;;
        *) echo "Error: $1"; exit 1;;
    esac
done

if [ -n "$PRINT_HELP" ]; then
    echo "auto-disper. Options:"
    echo "    -c --change		Switch to auto-detected profile"
    echo "    -d --default	Switch to default profile"
    echo "    -s --save NAME	Save current configuration as profile NAME."
    echo "    -l --load NAME	Load profile NAME."
    echo "    -t --toggle		If the default profile is not current, switch to it."
    echo "\t\t\tOtherwise, switch to auto-detected profile."
    echo "    -h --help		Print this message."
    exit 0
fi

CURRENT_SETUP="$($DISPER -l | grep '^display ')"

if [ -n "$SAVE_PROFILE" ]; then
    echo "Saving current configuration as profile '${SAVE_PROFILE}'"
    mkdir -p "$PROFILES/$SAVE_PROFILE"
    echo "$CURRENT_SETUP" > "$PROFILES/$SAVE_PROFILE/setup"
    $DISPER -p > "$PROFILES/$SAVE_PROFILE/config"
    #Note: not really sure if we should search for "default", and this has no multi-display support:
    XRANDR_ORIENTATION=$($XRANDR -q | grep default | cut -d ' ' -f4)
    if [ "$XRANDR_ORIENTATION" != "(normal" ]; then
        echo $XRANDR_ORIENTATION > "$PROFILES/$SAVE_PROFILE/xrandr-orientation"
    fi
    exit 0
fi

if [ -n "$LOAD_PROFILE" ]; then
    CHANGE_PROFILE=1 load "$LOAD_PROFILE"
    exit $?
fi

for SETUP_FILE in $PROFILES/*/setup; do
    if ! [ -e $SETUP_FILE ]; then
        break
    fi
    PROFILE="$(basename $(dirname "$SETUP_FILE"))"
    echo -n "$PROFILE"

    if blocked "$PROFILE"; then
        echo " (blocked)"
        continue
    fi

    FILE_SETUP="$(cat "$PROFILES/$PROFILE/setup")"
    if [ "$CURRENT_SETUP" = "$FILE_SETUP" ]; then
        echo " (detected)"
        if [ "$CHANGE_PROFILE" -eq 1 ]; then
            load "$PROFILE"
            # found the profile, exit with success
            exit 0
        elif [ "$CHANGE_PROFILE" -eq 2 ]; then
            ACTIVE_CONFIG="$($DISPER -p)"
            FILE_CONFIG="$(cat "$PROFILES/$PROFILE/config")"
            if [ "$ACTIVE_CONFIG" != "$FILE_CONFIG" ]; then
                load "$PROFILE"
                # found the profile, exit with success
                exit 0
            fi
        fi
    else
        echo ""
    fi
done

# we did not find the profile, load default
if [ -n "$DEFAULT_PROFILE" ]; then
    echo "No suitable profile detected, falling back to $DEFAULT_PROFILE"
    load "$DEFAULT_PROFILE"
fi
exit 1