#!/bin/sh
#
# Set wallpaper for awesome.
# Copyright (c) 2008 Julien Danjou <julien@danjou.info>
# 
# Derived from fbsetbg:
# Copyright (c) 2003-2004 Han Boetes <han@mijncomputer.nl>
#
# Permission is hereby granted, free of charge, to any person obtaining
# a copy of this software and associated documentation files (the
# "Software"), to deal in the Software without restriction, including
# without limitation the rights to use, copy, modify, merge, publish,
# distribute, sublicense, and/or sell copies of the Software, and to
# permit persons to whom the Software is furnished to do so, subject to
# the following conditions:
#
# The above copyright notice and this permission notice shall be
# included in all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
# IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
# CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
# TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
# SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

# Portability notes:
# To guarantee this script works on all platforms that support awesome
# please keep the following restrictions in mind:
#
# - don't use if ! command;, use command; if [ $? -ne 0 ];
# - don't use [ -e file ] use [ -r file ]
# - don't use $(), use ``
# - don't use ~, use ${HOME}
# - don't use id -u or $UID, use whoami
# - don't use echo -e
# - getopts won't work on all platforms, but the config-file can
#   compensate for that.
# - various software like grep/sed/perl may be not present or not
#   the version you have. for example grep '\W' only works on gnu-grep.
#   Keep this in mind, use bare basic defaults.
# - Do _NOT_ suggest to use #!/bin/bash. Not everybody uses bash.

# TODO purheps: xprop -root _WIN_WORKSPACE
# _NET_CURRENT_DESKTOP

if [ -z "$XDG_CACHE_HOME" ]
then
    CONFIG_DIR="${HOME}/.cache/awesome"
else
    CONFIG_DIR="${XDG_CACHE_HOME}/awesome"
fi

# The wallpapersetter is selected in this order
wpsetters="${wpsetters:=Esetroot habak wmsetbg feh hsetroot chbg display qiv xv xsri xli xsetbg}" # broken icewmbg'
lastwallpaper="${CONFIG_DIR}/lastwallpaper"


WHOAMI=`whoami`
[ "$WHOAMI" = root ] && PATH=/bin:/usr/bin/:/usr/local/bin:/usr/X11R6/bin

command="`basename \"$0\"`"


# Functions
display_usage() {
    cat << EOF
Usage: $command [-u/-U [wallpapersetter]] [-fFcCtTaA] [-m #] /path/to/wallpaper
       $command [-u/-U [wallpapersetter]] [-fFcCtTaA] [-m #] -r/-R /path/to/wallpaperdirectory
       $command [-lhip]
Use \`\`$command -h'' for a complete help message.

EOF
}

display_help() {
    display_usage
    cat << EOF

Options:

    -f  Set fullscreen wallpaper (default).
    -c  Set centered wallpaper.
    -t  Set tiled wallpaper.
    -a  Set maximized wallpaper, preserving aspect.
        ( if your bgsetter doesn't support this
          we fall back to -f )
    -u  Use specified wallpapersetter, use no argument to forget.
    -r  set random wallpaper from a directory

    -F,-C,-T,-A,-U,-R same as uncapsed but without remembering.

    -h  Display this help.

    -l  Set previous wallpaper.

    -i  Information about selected wallpaper command.

    -m  # Use montage to create a big image (image should
          fit screen size). Requires montage(1).
        # is the number of screen (columns in montage)
Files:

    \$XDG_CACHE_HOME/awesome/lastwallpaper     In this file the wallpaper you set
                                               will be stored, for the -l option.
Environment variables:
    wpsetters   Wallpapersetters to use.
                example:
                  wpsetters=feh awsetbg wallpaper.jpg

    DISPLAY     The display you want to set the wallpaper on.
                example:
                  DISPLAY=:0.0 awsetbg -l

EOF
}

find_it() {
    [ -n "$1" ] && hash $1 2> /dev/null
}

message() {
    extra_args="-default okay"
    if find_it gxmessage; then
        gxmessage $extra_args -center "$command: $@" &
    else
        xmessage $extra_args -center "$command: $@" &
    fi
}

remembercommand() {
    grep -vs "|${DISPLAY}$" ${lastwallpaper} > ${lastwallpaper}.tmp
    mv -f ${lastwallpaper}.tmp ${lastwallpaper}
    # Make dir/../../path/file.jpg work
    case $wallpaper in
        # no spaces allowed between the varname and '|'
        /*) echo $option $option2"|$wallpaper|$style|"$DISPLAY >> $lastwallpaper ;;
        *)  echo $option $option2"|$PWD/$wallpaper|$style|"$DISPLAY >> $lastwallpaper ;;
    esac
}

debugawsetbg() {
    echo
    echo $debugstory
    echo $sad_esetroot_story
    exit 0
}

if [ $# -eq 0 ]; then
    message "no options given"
    display_usage
    exit 1
fi

# create directory and last wallpaper file 
if [ ! -d  "${CONFIG_DIR}" ]; then
        mkdir -p "${CONFIG_DIR}"
    touch ${lastwallpaper}
fi

unset debug setterfromcommandline
# Parse command-line options
while [ $# -gt 0 ]; do
    case "$1" in
        -u)
            if find_it "$2"; then
                grep -v wpsetters $lastwallpaper > ${lastwallpaper}.tmp
                echo "wpsetters $2" >> ${lastwallpaper}.tmp
                mv ${lastwallpaper}.tmp $lastwallpaper
                WPSETTER=$2
                setterfromcommandline=true
            elif [ -z "$2" ]; then
                grep -v wpsetters $lastwallpaper > ${lastwallpaper}.tmp
                mv ${lastwallpaper}.tmp $lastwallpaper
                message "wpsetter removed from historyfile"
                exit 0
            else
                message "Couldn't find \"$2\" for wallpapersetter"
                display_usage
                exit 1
            fi
            shift 2 ;;
        -U)
            if find_it "$2"; then
                WPSETTER=$2
                setterfromcommandline=true
            else
                message "Couldn't find \"$2\" for wallpapersetter"
                display_usage
                exit 1
            fi
            shift 2 ;;
        -i) debug=true
            break ;;
        -a) option='$aspect'
            shift ;;
        -f) option='$full'
            shift ;;
        -c) option='$center'
            shift ;;
        -t) option='$tile'
            shift ;;
        -A) option='$aspect'
            remember=false
            shift ;;
        -F) option='$full'
            remember=false
            shift ;;
        -C) option='$center'
            remember=false
            shift ;;
        -T) option='$tile'
            remember=false
            shift ;;
        -m)
            montage=`which montage`
            if test ! -z "$montage"; then
                shift
                cols="$1"; shift
                fns=""
                for i in `seq $cols`; do
                    fns="$fns $1";
                done;
                shift
                $montage $fns -geometry +0+0 -tile ${cols}x $CONFIG_DIR/montage.png
                wallpaper=$CONFIG_DIR/montage.png
            else
                shift
                echo "montage not found. Falling back to single image"
            fi
            ;;
        -r) option2=$option
            option=random
            wallpaper=$2 # in this case it's a dir
            break ;;
        -R) option2=$option
            option=random
            wallpaper=$2 # in this case it's a dir
            remember=false
            break ;;
        -l)
            if [ -r "$lastwallpaper" ]; then
                option=`grep "|${DISPLAY}$"    $lastwallpaper|cut -d'|' -f1`
                option2=`echo $option|cut -d' ' -f2`
                option=`echo $option|cut -d' ' -f1`
                wallpaper=`grep "|${DISPLAY}$" $lastwallpaper|cut -d'|' -f2`
                if [ -z "$wallpaper" ]; then
                    option=`grep "|${DISPLAY}.0$"    $lastwallpaper|cut -d'|' -f1`
                    option2=`echo $option|cut -d' ' -f2`
                    option=`echo $option|cut -d' ' -f1`
                    wallpaper=`grep "|${DISPLAY}.0$" $lastwallpaper|cut -d'|' -f2`
                fi
                if [ -z "$wallpaper" ]; then
                    message "No previous wallpaper recorded for display ${DISPLAY}"
                    exit 1
                fi
            else
                message "No previous wallpaper recorded for display ${DISPLAY}"
                exit 1
            fi
            remember=false
            break ;;
        -z)
            if [ -r "$lastwallpaper" ]; then
                option=`grep "|${DISPLAY}$"    $lastwallpaper|cut -d'|' -f1`
                option2=`echo $option|cut -d' ' -f2`
                option=`echo $option|cut -d' ' -f1`
                style=`grep "|${DISPLAY}$" $lastwallpaper|cut -d'|' -f3`
                wallpaper=`grep "|${DISPLAY}$" $lastwallpaper|cut -d'|' -f2`
                if [ -z "$wallpaper" ]; then
                    option=`grep "|${DISPLAY}.0$"    $lastwallpaper|cut -d'|' -f1`
                    option2=`echo $option|cut -d' ' -f2`
                    option=`echo $option|cut -d' ' -f1`
                    style=`grep "|${DISPLAY}.0$" $lastwallpaper|cut -d'|' -f3`
                    wallpaper=`grep "|${DISPLAY}.0$" $lastwallpaper|cut -d'|' -f2`
                fi
            fi
            if [ "$style" != "style" -a -n "$wallpaper" ]; then
                remember=false
                break
            fi
            style="style"
            shift ;;
        -Z)
            style="style"
            shift ;;
        -h) display_help ; exit 0 ;;
        --)
            message "$command doesn't recognize -- gnu-longopts."
            message 'Use $command -h for a help message.'
            display_usage
            exit 1 ;;
        -*)
            message "unrecognized option "\`"$1'"
            display_usage
            exit 1 ;;
        *)
            if [ "$option" = random ]; then
                option='$aspect'
            elif [ ! -r "$1" ]; then
                message "$1 isn't an existing wallpaper or a valid option."
                display_usage
                exit 1
            elif [ -z "$1" ]; then
                message 'No wallpaper to set'
                display_usage
                exit 1
            else
                wallpaper=$1
                break
            fi ;;
    esac
done

# Find the default wallpapersetter
if [ "$setterfromcommandline" != true ]; then
    if [ -r "$lastwallpaper" ]; then
        wpsetters="`awk '/wpsetters/ {print $2}' $lastwallpaper` $wpsetters"
    fi
    for wpsetter in $wpsetters; do
        if find_it $wpsetter; then
            if [ ! "$wpsetter" = Esetroot ]; then
                WPSETTER=$wpsetter
                break
            elif ldd `which Esetroot`|grep libImlib 2>&1 > /dev/null; then
                WPSETTER=$wpsetter
                break
            else
                sad_esetroot_story="I also found Esetroot, but it doesn't have support for setting wallpapers. You need to install libimlib2 and rebuild Eterm to get it working."
            fi
        fi
    done
fi

standardrant=\
"$WPSETTER doesn't set the wallpaper properly. Transparency for awesome and
apps like aterm and xchat won't work right with it. Consider installing
feh, wmsetbg (from windowmaker) or Esetroot (from Eterm) and I'll use
them instead."

standardok=\
"$WPSETTER is a nice wallpapersetter. You won't have any problems."

case $WPSETTER in
    chbg)
        full='-once -mode maximize'
        tile='-once -mode tile'
        center='-once -mode center'
        aspect='-once -mode smart -max_grow 100 -max_size 100'
        debugstory="chbg supports all features but it doesn't report errors. I reported this bug to the chbg developers."
        ;;
    xsri)
        full='--center-x --center-y --scale-width=100 --scale-height=100'
        tile='--tile'
        center='--center-x --center-y --color=black'
        aspect='--center-x --center-y --scale-width=100 --scale-height=100 --keep-aspect --color=black'
        debugstory=$standardok
        ;;
    display)
        full="-sample `xwininfo -root 2> /dev/null|awk '/geom/{print $2}'` -window root"
        tile='-window root'
        center='-backdrop -window root'
        aspect="`xwininfo -root 2> /dev/null|grep geom` -window root"
        debugstory=$standardrant
        ;;
    Esetroot)
        full='-scale'
        tile=''
        center='-c'
        aspect='-fit'
        debugstory=$standardok
        ;;
    wmsetbg)
        full='-s -S'
        tile='-t'
        center='-b black -e'
        aspect='-b black -a -S'
        debugstory=$standardok
        ;;
    xsetbg)
        tile='-border black'
        center='-center -border black'
        aspect='-fullscreen -border black'
        full=$aspect #broken
        debugstory="xsetbg is actually xli. The fillscreen option (-f) is broken, defaults to (-a). $standardrant"
        ;;
    xli)
        tile='-onroot -quiet -border black'
        center='-center -onroot -quiet -border black'
        aspect='-fullscreen -onroot -quiet -border black'
        full=$aspect #broken
        debugstory="The fillscreen option (-f) is broken, defaults to (-a). $standardrant"
        ;;
    qiv)
        full='--root_s'
        tile='--root_t'
        center='--root'
        aspect='-m --root'
        debugstory=$standardrant
        ;;
    xv)
        full='-max -smooth -root -quit'
        tile='-root -quit'
        center='-rmode 5 -root -quit'
        aspect='-maxpect -smooth -root -quit'
        debugstory=$standardrant
        ;;
    feh)
        full='--bg-scale'
        tile='--bg-tile'
        center='--bg-center'
        aspect=$full
        debugstory=$standardok
        ;;
    hsetroot)
        full='-fill'
        tile='-tile'
        center='-center'
        aspect='-full'
        debugstory=$standardok
        ;;
    habak)
        full='-ms'
        tile=''
        center='-mC'
        aspect='-mS'
        debugstory=$standardok
        ;;
    icewmbg)
        tile='-s'
        full=$tile
        center=$tile
        aspect=$tile
        debugstory="icewmbg does support transparency, but only tiling. And I noticed odd
errormessages with aterm. Don't use it unless you have to."
        ;;
    '')
        message \
"I can't find an app to set the wallpaper with. You can install one in
many many ways but I will give you some simple advice: install Eterm and
you're set. Eterm provides Esetroot and thats a great wallpaper setter. I
recommend you install the package provided by your distro."
        exit 1
        ;;
esac

if [ "$debug" = true ]; then
    debugawsetbg
    exit 0
fi

option=${option:='$full'}
option2=${option2:='$full'}


if [ -z "$DISPLAY" ]; then
    message "You are not connected to an X session\nPerhaps you should set the DISPLAY environment variable?"
    exit 1
fi


# random wallpaper code
if [ "$option" = random ]; then
    # Lets make one thing clear...
    wallpaperdir="$wallpaper"
    if [ -z "$wallpaperdir" ]; then
        message "No random wallpaper directory specified."
        exit 1
    fi
    if [ -d "$wallpaperdir" ]; then
        number_of_wallpapers=`ls "$wallpaperdir"|wc -l`
        if find_it random_number; then
            randomnumber=`random_number`
        # some shells don't support $RANDOM
        elif [ -z "$RANDOM" ]; then
            randomnumber=`(echo $$ ;time ps; w ; date )2>&1 | cksum | cut -f1 -d' '`
        else
            randomnumber="$RANDOM"
        fi
        wallpapernumber=`expr $randomnumber % $number_of_wallpapers + 1`
        #remember previous wallpaper
        if [ ! "$remember" = false ]; then
            remembercommand
        fi
        remember=false
        #set -x
        wallpaper="$wallpaperdir/`ls \"$wallpaperdir\"|sed -n ${wallpapernumber}p`"
        option=$option2 # have to choose something...
    else
        message "Invalid random wallpaper directory specified."
        exit 1
    fi
fi


if [ ! -r "$wallpaper" ]; then
    message "Can't find wallpaper $wallpaper"
    exit 1
fi


$WPSETTER `eval echo $option` "$wallpaper"
if [ $? -ne 0 ]; then
    message "Something went wrong while setting the wallpaper.
Run '$WPSETTER "`eval echo $option` $wallpaper"' from an xterm to find out what."
    exit 1
fi


#remember previous wallpaper
if [ ! "$remember" = false ]; then
    remembercommand
fi