#!/bin/bash

### CONFIGURATION ###

# tell me where the NASA images should be stored to (it is created atomatically)
USERDIR="$HOME/.NASA-blue-marble-collection"

# where to download monthly images from; provide a full URL with [[[MONTH]]] as a placeholder for the months number
MONTHURL="http://gridportal-ws01.hep.ph.ic.ac.uk/bluemarble_all_year/world.topo.bathy.2004[[[MONTH]]].3x5400x2700.jpg"

# if you have a special topography file insert the URL here
TOPOGRAPHY="http://ia600506.us.archive.org/10/items/VE-IMG-8391/srtm_ramp2.world.5400x2700.jpg"

# if you have a special night map, insert URL here
NIGHTMAP="https://netfiles.uiuc.edu/cmampre2/www/Pictures/Desktopables/earth_lights_lrg.jpg"

# copy the monthly image to this location:
TARGETTEXTURE="$HOME/.xplanetFX/base/earth.jpg"

# copy the bump map to this location (if you have one):
TARGETTOPOGRAPHY="$HOME/.xplanetFX/base/earth_bump.jpg"

# copy the nightly image to this location (if you have one):
TARGETNIGHTMAP="$HOME/.xplanetFX/base/earth_night.jpg"

# the final resolution of the images:
TARGETSIZE="2500x1250"

# Options for wget
WGETOPTIONS="--user-agent=\"Mozilla/5.0\" --referer=\"http://google.com\" --header=\"Accept:text/xml,application/xml,application/xhtml+xml,text/html;q=0.9,text/plain;q=0.8,image/png,*/*;q=0.5\" --header=\"Accept-Language:en-us,en;q=0.5\" --header=\"Accept-Encoding:gzip,deflate\" --header=\"Accept-Charset:ISO-8859-1,utf-8;q=0.7,*;q=0.7\" --header=\"Keep-Alive:300\""

function copyimages() {
    convert $USERDIR/`date +%m`.jpg -resize $TARGETSIZE $TARGETTEXTURE
    if [ "$TOPOGRAPHY" != "" -a -f $USERDIR/topo.jpg ]; then
        convert $USERDIR/topo.jpg -resize $TARGETSIZE $TARGETTOPOGRAPHY
    fi
    if [ "$NIGHTMAP" != "" -a -f $USERDIR/night.jpg ]; then
        convert $USERDIR/night.jpg -resize $TARGETSIZE $TARGETNIGHTMAP
    fi
    echo `date +%m` > $USERDIR/monthid
    echo `date -r $TARGETTEXTURE +%F\ %H:%M:%S` > $USERDIR/timestamp
}

### CLEANUP FOR REFRESHING IMAGES ###
if [ "$1" == "--refresh" -o "$1" == "-r" ]; then
    rm -r $USERDIR
fi

### FORCE COPYING ###
if [ "$1" == "--force" -o "$1" == "-f" ]; then
    rm $USERDIR/timestamp $USERDIR/monthid
fi

### SETUP AND DOWNLOAD ###
if [ ! -d $USERDIR ]; then
    mkdir -p $USERDIR
    MONTH=1
    while [ $MONTH -lt 13 ]; do
        M=`printf %.2d $MONTH`
        U=`echo $MONTHURL | sed "s#\[\[\[MONTH\]\]\]#$M#"`
        wget $WGETOPTIONS --output-document $USERDIR/$M.jpg $U
        let MONTH=$MONTH+1
    done
    if [ "$TOPOGRAPHY" != "" ]; then
        wget $WGETOPTIONS --output-document="$USERDIR/topo.jpg" $TOPOGRAPHY
    fi
    if [ "$NIGHTMAP" != "" ]; then
        wget $WGETOPTIONS --output-document="$USERDIR/night.jpg" $NIGHTMAP
    fi
fi

### CREATE TIMESTAMP ###
if [ ! -f $USERDIR/timestamp ]; then
    touch $USERDIR/timestamp
fi

### CREATE MONTHID ###
if [ ! -f $USERDIR/monthid ]; then
    touch $USERDIR/monthid
fi

### UPDATE IMAGE IF NECESSARY ###
LASTDATE=`date -r $TARGETTEXTURE +%F\ %H:%M:%S`
ACTMONTH=`date +%m`
if [ "$LASTDATE" != "`cat $USERDIR/timestamp`" -o "$ACTMONTH" != "`cat $USERDIR/monthid`" ]; then
    copyimages
fi