#!/bin/bash
#
#  Execution:  % findbugs -cos226 HelloWorld.class
#  Execution:  % findbugs -cos126 *.class
#
#  To see descriptions of bugs:  http://findbugs.sourceforge.net/bugDescriptions.html

# set -o xtrace

usage() {
    echo "Usage: ${0##*/} [-cos126 | -cos226 | -algs4 | -introcs | -coursera] classname1 classname2 ..."
    exit 1
}
INSTALL_ALGS4=/usr/local/algs4
INSTALL_INTROCS=/usr/local/introcs
JAVA=java

# find the latest version of Findbugs
FINDBUGS_VERSION=findbugs-[0-9].[0-9].[0-9]
FINDBUGS_JAR=$(ls -td ${INSTALL_ALGS4}/${FINDBUGS_VERSION}/lib/findbugs.jar | head -1)
FINDBUGS=$(ls -td ${INSTALL_ALGS4}/${FINDBUGS_VERSION}/bin/findbugs | head -1)

# no command-line arguments
if [ ! -n "$1" ]; then
    echo 'Specify .class or .jar files as arguments.'
    usage
fi

# check for command-line options
if [ "$1" == "-cos126" ]; then
        echo 'Detected cos126'
        AUX_CLASSPATH=${INSTALL_INTROCS}/stdlib.jar
        FINDBUGS_XML=${INSTALL_INTROCS}/findbugs.xml
        shift
elif [ "$1" = "-cos226" ]; then
        echo 'Detected cos226'
        AUX_CLASSPATH=${INSTALL_ALGS4}/algs4.jar
        FINDBUGS_XML=${INSTALL_ALGS4}/findbugs.xml
        shift
elif [ "$1" = "-algs4" ]; then
        echo 'Detected algs4'
        AUX_CLASSPATH=${INSTALL_ALGS4}/algs4.jar
        FINDBUGS_XML=${INSTALL_ALGS4}/findbugs.xml
        shift
elif [ "$1" = "-coursera" ]; then
        echo 'Detected coursera'
        AUX_CLASSPATH=${INSTALL_ALGS4}/algs4.jar
        FINDBUGS_XML=${INSTALL_ALGS4}/findbugs.xml
        shift
else
        echo "Running Findbugs on $*:"
        $FINDBUGS $*
        exit
fi

# if the first argument is either a .class or .java file that exists, runs findbugs
if [ "${1##*.}" = "class" ] || [ "${1##*.}" = "jar" ]; then
    if [ -e "$1" ]; then
        echo "Running findbugs on $*:"
        $JAVA -Duser.language=novice -jar "${FINDBUGS_JAR}" -textui -low -auxclasspath $AUX_CLASSPATH -longBugCodes -exclude "${FINDBUGS_XML}" $*
        exit
    else
        echo "File not found! Make sure you are specifying the path correctly."
        echo "The filename is case sensitive."
        usage
    fi
else
    echo "Findbugs needs .class or .jar files as arguments!"
    echo "The filename is case sensitive."
    usage
fi