#!/bin/bash

ARCHIVE_INDEX="index.catpak.lst"
ARCHIVE_CONTENT="index.catpak"

function create_packageset {
    truncate -s 0 ./$ARCHIVE_INDEX
    truncate -s 0 ./$ARCHIVE_CONTENT
    find -type f ! -iname "$ARCHIVE_INDEX" ! -iname "$ARCHIVE_CONTENT" -exec sh -c 'stat -c "%s^%n^%a" "$1" >> "./$2"; cat "$1" >> "./$3"' _ {} "$ARCHIVE_INDEX" "$ARCHIVE_CONTENT" \;
}

function extract_file {
    CHUNK=$(awk -F '^' -v needle="$1" 'BEGIN { sum = 0 } $2 == needle { print sum " " $1; exit 1 } $2 != needle { sum += $1 }' "./$ARCHIVE_INDEX")
    if [[ "$?" != "1" ]]
    then
        exit 1
    fi
    IFS=" " read -ra OFFLIM <<< "$CHUNK"
    dd if="./$ARCHIVE_CONTENT" of="/tmp/dumpdata" bs=1 skip="${OFFLIM[0]}" count="${OFFLIM[1]}" && \
    cat /tmp/dumpdata
    rm /tmp/dumpdata
}

function extract_all {
    OFFSET=0
    mkdir -p "$1"
    while read LISTENTRY
    do
	echo $LISTENTRY

        ITEMSIZE=$(cut -d^ -f1 <<< "$LISTENTRY")
        ITEMNAME="$1/$(cut -d^ -f2 <<< $LISTENTRY)"
        mkdir -p "$(dirname $ITEMNAME)"
        dd if="./$ARCHIVE_CONTENT" of="$ITEMNAME" bs=1 skip="$OFFSET" count="$ITEMSIZE"
        OFFSET=$(expr $OFFSET + $ITEMSIZE)
    done < "./$ARCHIVE_INDEX"
}

if [[ "$1" == "create" ]]
then
    create_packageset
elif [[ "$1" == "extract" ]]
then
    extract_file "./$2"
elif [[ "$1" == "extractall" ]]
then
    extract_all "/tmp/dumpie"
elif [[ "$1" == "squash" ]]
then
    create_packageset
    # tar czvf index.catpak.tgz "./$ARCHIVE_INDEX" "./$ARCHIVE_CONTENT"
    # rm "./$ARCHIVE_INDEX" "./$ARCHIVE_CONTENT"
    bzip2 "./$ARCHIVE_CONTENT"
elif [[ "$1" == "unsquash" ]]
then
    bzip2 -d -c "./$ARCHIVE_CONTENT.bz2" > "./$ARCHIVE_CONTENT"
    # tar xzvf index.catpak.tgz
    extract_file "./$2"
    # rm "./$ARCHIVE_INDEX" "./$ARCHIVE_CONTENT"
    rm "./$ARCHIVE_CONTENT"
fi