deb_functions

#!/usr/bin/env bash

# list packages installed explicitly by current user (using apt/aptitude)
# doesn't include upgraded packages
show_packages_installed_by_current_user() {
    readonly local user=$(whoami)
    cat /var/log/apt/history.log | awk -v USER="$user" 'BEGIN {
        FS="\n"
        RS=""
        user_pattern="Requested-By:.*" USER
        install_pattern="Install:.*"
    } $2 ~ user_pattern && NF > 3 && $3 ~ install_pattern {print $3 "\n"}' | sed 's/([^()]*)//g'
}

# list packages upgraded at given date
# $1 date formatted like /var/log/dpkg.log
# [$2] time pattern (otherwise not used) formatted HH:MM:SS
show_packages_upgraded_at() {
    if [ -z $2 ]; then
        awk -v DATE="$1" '$1==DATE && $3=="upgrade"' /var/log/dpkg.log
    else
        awk -v DATE="$1" -v TIME="$2" '$1==DATE && $2 ~ TIME && $3=="upgrade"' /var/log/dpkg.log
    fi
}

# check if previous version of packages upgraded at specified date are still available in packager cache
# $1 date of upgrade (formatted like in /var/log/dpkg.log)
# [$2] time pattern (otherwise not used) formatted HH:MM:SS
show_previous_packages_versions() {
    if [ -z $2 ]; then
        awk -v DATE="$1" '$1==DATE && $3=="upgrade" {gsub(/:/, "%3a", $5); split($4, f, ":"); print "/var/cache/apt/archives/" f[1] "_" $5 "_" f[2] ".deb"}' /var/log/dpkg.log | xargs -r ls -ld
    else
        awk -v DATE="$1" -v TIME="$2" '$1==DATE && $2 ~ TIME && $3=="upgrade" {gsub(/:/, "%3a", $5); split($4, f, ":"); print "/var/cache/apt/archives/" f[1] "_" $5 "_" f[2] ".deb"}' /var/log/dpkg.log | xargs -r ls -ld
    fi
}

# download and extract deb package in the current directory
# $1 package name (as listed in repo)
preview_deb_content() {
    # because apt-get -d install $1 won't download if package is already installed
    aptitude download $1
    ar vx ${1}*.deb
    #this will result in three files: data.tar.xz, control.tar.gz and debian-binary
}

# list all packages from given repo
list_repository_packages() {
  awk '/Package:.*/ {print $2}' $1
}