#!/bin/sh

##############################
#
# Standard Compile Script 
#
# Supported compilers: 
#   gcc, g++, and gpc.
#
##############################

export C_COMPILER=/usr/bin/gcc
export CPLUSPLUS_COMPILER=/usr/bin/g++
export PASCAL_COMPILER=/usr/bin/gpc

export C_OPTIONS="-O2 -Wall"
export CPLUSPLUS_OPTIONS="-O2 -Wall"
export PASCAL_OPTIONS="-O2 -Wall"

# Check for the correct number of arguments. Otherwise, print usage.
if [ $# -eq 0 -o $# -gt 4 ]
then
    echo "Usage: $0 <language> [<source-file>] [<output-file>] [<message-file>]"
    echo
    echo "<source-file>  is defaulted to \"source\"."
    echo "<output-file>  is defaulted to \"a.out\"."
    echo "<message-file> is defaulted to \"compiler_message\"."
    echo
    exit 127
fi

# Retrieve the arguments.
if [ $# -ge 1 ]
then
    export PROG_LANG=$1
    echo "programming language: ${PROG_LANG}"
fi

if [ $# -ge 2 ]
then
    export SOURCE_FILE=$2
else
    export SOURCE_FILE=source
fi
echo "         source file: $SOURCE_FILE"

if [ $# -ge 3 ]
then
    export OUTPUT_FILE=$3
else
    export OUTPUT_FILE=a.out
fi
echo "         output file: $OUTPUT_FILE"

if [ $# -eq 4 ]
then
    export MESSAGE_FILE=$4
else
    export MESSAGE_FILE=compiler_message
fi
echo "        message file: $MESSAGE_FILE"

echo

# Remove any remaining output files or message files.
rm -Rf $OUTPUT_FILE
rm -Rf $MESSAGE_FILE

# Check if the source file exists before attempt compiling.
if [ ! -f $SOURCE_FILE ]
then
    echo "ERROR: The source file does not exist!"
    echo "ERROR: The source file did not exist." > $MESSAGE_FILE
    exit 127
fi

# Compile.
if [ $PROG_LANG = "c" ]
then
    $C_COMPILER $C_OPTIONS -o $OUTPUT_FILE $SOURCE_FILE 2>$MESSAGE_FILE
elif [ $PROG_LANG = "c++" ]
then
    $CPLUSPLUS_COMPILER $CPLUSPLUS_OPTIONS -o $OUTPUT_FILE $SOURCE_FILE 2>$MESSAGE_FILE
elif [ $PROG_LANG = "pascal" ]
then
    $PASCAL_COMPILER $PASCAL_OPTIONS -o $OUTPUT_FILE $SOURCE_FILE 2>$MESSAGE_FILE
else
    echo "ERROR: Invalid language specified!"
    echo "ERROR: Invalid language specified!" > $MESSAGE_FILE
    exit 127
fi

# Report success or failure.
if [ -f $OUTPUT_FILE ]
then
    echo "Compilation was successful!"    
else
    echo "ERROR: Something was wrong during the compilation!"
    echo "Dumping compiler message:"
    echo
    cat $MESSAGE_FILE
fi