#!/bin/bash
set -euo pipefail
shopt -s inherit_errexit

USE_VALGRIND=0

usage() {
    echo "Usage: run_tests.sh [USE_VALGRIND]"
}

if [[ $# -gt 0 ]]; then
    if [[ $1 -eq "USE_VALGRIND" ]]; then
        USE_VALGRIND=1
    else
        echo "Invalid parameter $1."
        usage
        exit
    fi
    shift
fi

SCRATCH=$(mktemp --tmpdir -d huffman.XXXXXXXXXX)
# echo "Using temporary directory $SCRATCH"
cleanup() {
    # echo "Cleaning up $SCRATCH"
    rm -r "$SCRATCH"
}
trap cleanup EXIT

HUFFCODE="./huffcode"

if [[ $USE_VALGRIND == 1 ]]; then
    VALGRIND="valgrind --tool=memcheck --memcheck:leak-check=yes --leak-check=full --errors-for-leak-kinds=all --show-leak-kinds=all --track-origins=yes --error-exitcode=1"
    HUFFCODE="$VALGRIND $HUFFCODE"
fi

compress_test() {
    local IN=$1
    local OUT="$SCRATCH/$(basename $IN)"
    echo "compress_test $IN"
    set +e
    $HUFFCODE -i "$IN" -o "$OUT.compressed"
    if [ "$?" != 0 ]; then
        echo "FAILURE: huffcode encode failed on $IN"
        exit 1
    fi
    $HUFFCODE -d -i "$OUT.compressed" -o "$OUT.decompressed"
    if [ "$?" != 0 ]; then
        echo "FAILURE: huffcode decode failed on $OUT.compressed"
        exit 1
    fi
    diff "$OUT.decompressed" "$IN"
    if [ "$?" != 0 ]; then
        echo "FAILURE: huffcode decode didn't match original on $IN"
        exit 1
    fi
    set -e
}

# Only decompress. Does not verify against originally compressed file,
# but is used to make sure invalid code tables do not crash the decompressor.
decompress_test() {
    local IN=$1
    local OUT="$SCRATCH/$(basename $IN)"
    echo "decompress_test $IN"
    set +e
    $HUFFCODE -d -i "$IN" -o "$OUT.decompressed"
    local STATUS=$?
    if [ "$STATUS" != 1 ]; then
        echo "Expected test to fail with 1 but got $STATUS."
        exit 1
    fi
    set -e
}

echo "Basic Checks..."
compress_test "test_data/3_line"
compress_test "test_data/empty"
compress_test "test_data/1_byte"
compress_test "test_data/2_byte_2_symbol"
compress_test "test_data/2_byte_1_symbol"
compress_test "test_data/3_byte_1_symbol"
compress_test "test_data/3_byte_3_symbol"
compress_test "test_data/128_byte_1_symbol"
compress_test "test_data/128_byte_2_symbol"

echo "Issue 2 Regression Checks..."
for file in "test_data/reported_issues/issue2/"*; do
    decompress_test "$file"
done

echo "All Tests Passed"