#!/bin/sh
# Outputs APT configuration data

set -e

self="$(basename "$0")"

# TODO
# - currently only handles a single --suite or --profile; allow multiple ones?
# - nicer error messages
# - default output when neither --suite nor --profile is set?
# - support getting/setting --archive?
# - support setting --mirror-map (for --profile)
# - Debian security entries?

log() {
    echo "$@" >&2
}

usage() {
    log "$self [--with-sources=[yes|no|disabled]] [--arch=<arch>] [--components=<comp1>,<comp2>] [--mirror=<mirror>] [--suite=<suite>] [--pockets=<pocket1>,<pocket2>]" >&2
    log "$self [--with-sources=[yes|no|disabled]] [--arch=<arch>] [--components=<comp1>,<comp2>] [--profile=<profile>]" >&2
}

die() {
    log "$@"
    exit 1
}

guess_dist_arch_archive() {
    local dist="$1"
    local arch="$2"

    case "$dist" in
      etch|lenny|squeeze|sid|testing|unstable|experimental)
        echo "debian"
      ;;
      hardy|intrepid|jaunty|karmic|lucid)
        case "$arch" in
          amd64|i386)
            echo "ubuntu"
          ;;
          armel|hppa|ia64|lpia|powerpc|sparc)
            echo "ubuntu-ports"
          ;;
          *)
            die "Unknown Ubuntu archive for arch=$arch"
          ;;
        esac
      ;;
      *)
        die "Unknown archive for dist=$dist"
      ;;
    esac
}

get_archive_url() {
    local archive="$1"

    case "$archive" in
      backports.org)
        echo "http://www.backports.org/backports.org/"
      ;;
      debian)
        echo "http://ftp.us.debian.org/debian/"
      ;;
      ubuntu)
        echo "http://archive.ubuntu.com/ubuntu/"
      ;;
      ubuntu-ports)
        echo "http://ports.ubuntu.com/ubuntu-ports/"
      ;;
      volatile)
        echo "http://volatile.debian.org/debian-volatile/"
      ;;
      *)
        die "Unknown mirror for archive=$archive"
      ;;
    esac
}

output_sources() {
    local with_sources="$1"
    local mirror="$2"
    local dist="$3"
    local components="$4"

    case "$with_sources" in
      yes)
        echo "deb     $mirror $dist $components"
        echo "deb-src $mirror $dist $components"
      ;;
      disabled)
        echo "deb     $mirror $dist $components"
        echo "#deb-src $mirror $dist $components"
      ;;
      no)
        echo "deb $mirror $dist $components"
      ;;
      *)
        die 'with_sources must be either "yes", "disabled", or "no"'
      ;;
    esac
}

getopt_output="`getopt -o "" -l with-sources::,arch:,components:,mirror:,suite:,pockets:,profile: -n "$self" -s sh -- "$@"`"

eval set -- "$getopt_output"

with_sources="disabled"
arch="`dpkg --print-architecture`"
components="main"
mirror=""
suite=""
pockets=""
archive=""
profile=""

while :; do
    case "$1" in
      --with-sources)
        case "$2" in
          "")
            with_sources="yes"
          ;;
          yes|no|disabled)
            with_sources="$2"
          ;;
          *)
            die '--with-sources must be either "yes", "disabled", or "no"'
          ;;
        esac
        shift 2
      ;;
      --arch)
        arch="$2"
        shift 2
      ;;
      --components)
        components="$2"
        shift 2
      ;;
      --mirror)
        mirror="$2"
        shift 2
      ;;
      --suite)
        if [ -z "$2" ]; then
            die "Need a suite for --suite"
        fi
        if [ -n "$profile" ]; then
            die "Can't set --suite after --profile"
        fi
        suite="$2"
        shift 2
      ;;
      --pockets)
        pockets="$2"
        shift 2
      ;;
      --archive)
        archive="$2"
        shift 2
      ;;
      --profile)
        if [ -z "$2" ]; then
            die "Need a profile for --profile"
        fi
        if [ -n "$suite" ]; then
            die "Can't set --profile after --suite"
        fi
        profile="$2"
        shift 2
      ;;
      --)
        shift
        break
      ;;
      *)
        die "Unhandled arg=$1"
      ;;
    esac
done

case $# in
  0)
    command="sources"
  ;;
  1)
    command="$1"
  ;;
  2)
    usage
    exit 1
  ;;
esac

if [ -z "$suite" ] && [ -z "$profile" ]; then
    die "Please pass --suite or --profile"
fi

components="$(echo "$components" | tr , " ")"
pockets="$(echo "$pockets" | tr , " ")"

if [ -n "$profile" ]; then
    base_dist="${profile%%/*}"
    base_dist="${base_dist%%-*}"
    base_archive="`guess_dist_arch_archive "$base_dist" "$arch"`"
    base_mirror="`get_archive_url "$base_archive"`"
    case "$base_archive" in
      debian)
        case "$profile" in
          experimental)
            base_dist="unstable"
            output_sources "$with_sources" "$base_mirror" "$base_dist" "$components"
            output_sources "$with_sources" "$base_mirror" "$profile" "$components"
          ;;
          */volatile|*/volatile-sloppy)
            if [ "$base_dist" != "${profile%%/*}" ]; then
                die "Unknown Volatile based profile=$profile"
            fi
            archive="volatile"
            mirror="`get_archive_url "$archive"`"
            volatile_dist=${profile%%-*}
            output_sources "$with_sources" "$base_mirror" "$base_dist" "$components"
            output_sources "$with_sources" "$mirror" "$volatile_dist" "$components"
            if [ "$volatile_dist" != "$profile" ]; then
                output_sources "$with_sources" "$mirror" "$profile" "$components"
            fi
          ;;
          *-backports)
            if [ "$base_dist" != "${profile%%-*}" ]; then
                die "Unknown Backports.org based profile=$profile"
            fi
            archive="backports.org"
            mirror="`get_archive_url "$archive"`"
            output_sources "$with_sources" "$base_mirror" "$base_dist" "$components"
            output_sources "$with_sources" "$mirror" "$profile" "$components"
          ;;
          *-proposed-updates)
            if [ "$base_dist" != "${profile%%-*}" ]; then
                die "Unknown Debian updates based profile=$profile"
            fi
            output_sources "$with_sources" "$base_mirror" "$base_dist" "$components"
            output_sources "$with_sources" "$base_mirror" "$profile" "$components"
          ;;
          *)
            if [ "$base_dist" != "$profile" ]; then
                die "Unknown Debian based profile=$profile"
            fi
            output_sources "$with_sources" "$base_mirror" "$base_dist" "$components"
          ;;
        esac
      ;;
      ubuntu)
        if [ "$base_dist" != "${profile%%-*}" ]; then
            die "Unknown Ubuntu based profile=$profile"
        fi
        pockets=""
        case "$profile" in
          *-security)
            pockets="security"
          ;;
          *-updates)
            pockets="security updates"
          ;;
          *-backports)
            pockets="security updates backports"
          ;;
          *-proposed)
            pockets="security updates proposed"
          ;;
          *)
            if [ "$base_dist" != "$profile" ]; then
                die "Unknown Ubuntu pocket based profile=$profile"
            fi
          ;;
        esac
        output_sources "$with_sources" "$base_mirror" "$base_dist" "$components"
        for pocket in $pockets; do
            output_sources "$with_sources" "$base_mirror" "$base_dist-$pocket" "$components"
        done
      ;;
      *)
        die "Unknown profile for base_archive=$base_archive"
      ;;
    esac
    exit 0
fi

if [ -n "$suite" ]; then
    if [ -z "$mirror" ]; then
        if [ -z "$archive" ]; then
            archive="`guess_dist_arch_archive "$suite" "$arch"`"
        fi
        mirror="`get_archive_url "$archive"`"
    fi
    output_sources "$with_sources" "$mirror" "$suite" "$components"
    for pocket in $pockets; do
        output_sources "$with_sources" "$mirror" "$suite-$pocket" "$components"
    done
    exit 0
fi