XCOMM!/bin/ksh
XCOMM
XCOMM dtapp - provide an interface for some useful applications.
XCOMM
XCOMM #############################################################
XCOMM #set -x           # uncomment for debugging
XCOMM ###############################################################
XCOMM Init

DTAPP="dtapp"                   # Identity crisis
APPNAME="$(basename $0)"        # the app to locate/run

XCOMM apps to look for, given an action (based on APPNAME - see MAIN)

XCOMM image viewing
if [ -z "$DTAPP_VIMAGE" ]
then
    VIMAGE="xv display gimp"
else
    VIMAGE="$DTAPP_VIMAGE"
fi

XCOMM video viewing
if [ -z "$DTAPP_VVIDEO" ]
then
    VVIDEO="vlc ffplay"
else
    VVIDEO="$DTAPP_VVIDEO"
fi

XCOMM postscript viewing
if [ -z "$DTAPP_VPS" ]
then
    VPS="mgv gv"
else
    VPS="$DTAPP_VPS"
fi

XCOMM PDF viewing
if [ -z "$DTAPP_VPDF" ]
then
    VPDF="okular xpdf"
else
    VPDF="$DTAPP_VPDF"
fi

XCOMM ##############################################################
XCOMM ## Utility Functions

XCOMM ## Find the path of a program
FindProg()
{
    # FindProg "program"
    # - returns full path, or ""

    whence $1

    return 0
}

XCOMM ## Show an error message
ErrorMsg()
{
    # ErrorMsg "Title "Message" ["OK"]
    # use dterror.ds to display it...

    if [ -z "$3" ]
    then    # default to 'OK'
        OKM="OK"
    else
        OKM="$3"
    fi

    CDE_INSTALLATION_TOP/bin/dterror.ds "$2" "$1" "$OKM"

    return 0
}

XCOMM ## do a simple command
DoSimpleCmd()
{
    # DoSimpleCmd "commands" args

    didone=0
    cmds="$1"
    shift
    args="$*"

    for i in $cmds
    do
        thecmd="$(FindProg $i)"

        if [ ! -z "$thecmd" ]
        then    # it's there
            $thecmd "$args"
            didone=1
            break
        fi
    done

    if [ $didone -eq 0 ]
    then    # couldn't find a viewer
        ErrorMsg "Helper not found" \
                 "${DTAPP}: Could not find any of the following\ncommands for this file type:\n\n$cmds"
    fi

    return 0
}


XCOMM ##################################################################
XCOMM ## MAIN

XCOMM # We'll just look at our args and decide what to do...

XCOMM # Commands we'll recognize

COMMANDS="dtapp_vimage dtapp_vweb dtapp_vpdf dtapp_vps dtapp_vvideo"

case $APPNAME in
    dtapp_vimage)
        DoSimpleCmd "$VIMAGE" $*
        ;;
    dtapp_vpdf)
        DoSimpleCmd "$VPDF" $*
        ;;
    dtapp_vps)
        DoSimpleCmd "$VPS" $*
        ;;
    dtapp_vvideo)
        DoSimpleCmd "$VVIDEO" $*
        ;;
    *)
        # Unknown
        ErrorMsg "${DTAPP}: Unknown Helper Application" \
                  "\"$APPNAME\" is not a recognized Helper Application.  \nKnown Helper Applications are:\n\n$COMMANDS"
        ;;
esac

XCOMM # Fini
exit 0