#!/bin/sh
#
# Copyright (C) 2014, 2017, 2021  Etersoft
# Copyright (C) 2014, 2017, 2021  Vitaly Lipatov <lav@etersoft.ru>
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU Affero General Public License for more details.
#
# You should have received a copy of the GNU Affero General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.
#

# apt-file like. See also
# https://bugzilla.altlinux.org/show_bug.cgi?id=14449

# convert "http://download.etersoft.ru/pub/ALTLinux/p8/branch x86_64" to ALTLinux/p8/branch/x86_64
get_alt_repo_path()
{
    local DN1=$(dirname "$1")
    local DN2=$(dirname $DN1)
    local DN3=$(dirname $DN2)

    local BN0=$(basename "$1") # arch
    local BN1=$(basename $DN1) # branch/Sisyphus
    local BN2=$(basename $DN2) # p8/ALTLinux
    local BN3=$(basename $DN3) # ALTLinux/

    [ "$BN1" = "branch" ] && echo "$BN3/$BN2/$BN1/$BN0" || echo "$BN2/$BN1/$BN0"
}

# convert "http://download.etersoft.ru/pub/ALTLinux/p8/branch x86_64" to /tmp/epm/ALTLinux/p8/branch/x86_64
get_local_alt_mirror_path()
{
    # TODO: /var/cache/eepm
    echo "$TMPDIR/eepm/$(get_alt_repo_path "$1")"
}

ALT_CONTENTS_INDEX_LIST=$TMPDIR/eepm/contents_index_list

__local_ercat()
{
   local i
   for i in "$@" ; do
       case "$i" in
           *.xz)
               a='' xzcat $i
               ;;
           *.lz4)
               a='' lz4cat $i
               ;;
           *.gz)
               a='' zcat $i
               ;;
           *.failed)
               # just ignore
               ;;
           *)
               cat $i
               ;;
       esac
   done
}

# URL TARGETDIR OPTIONS
rsync_alt_contents_index()
{
    local URL="$1"
    local TD="$2"
    assure_exists rsync
    mkdir -p "$(dirname "$TD")"
    if [ -n "$verbose" ] ; then
        docmd rsync --partial --inplace $3 -a --progress "$URL" "$TD"
    else
        a= rsync --partial --inplace $3 -a --progress "$URL" "$TD" >/dev/null 2>/dev/null
    fi
}

# URL
get_url_to_etersoft_mirror()
{
    local REPOPATH
    local ETERSOFT_MIRROR="rsync://download.etersoft.ru/pub"
    local ALTREPO=$(get_alt_repo_path "$1")
    echo "$ALTREPO" | grep -q "^ALTLinux" || return
    echo "$ETERSOFT_MIRROR/$(get_alt_repo_path "$1" | sed -e "s|^ALTLinux/|ALTLinux/contents_index/|")"
}

__init_contents_index_list()
{
    mkdir -p "$(dirname $ALT_CONTENTS_INDEX_LIST)"
    truncate -s0 $ALT_CONTENTS_INDEX_LIST
}

# "comment" "file"
__add_to_contents_index_list()
{
    [ -n "$quiet" ] || echo "  $1 -> $2"
    echo "$2" >>$ALT_CONTENTS_INDEX_LIST
}

# "comment" file file2
__add_better_to_contents_index_list()
{
    if [ -s "$2" ] && [ -s "$3" ] ; then
        [ "$2" -ot "$3" ] && __add_to_contents_index_list "$1" "$3" && return
        __add_to_contents_index_list "$1" "$2" && return
    fi
    [ -s "$2" ] && __add_to_contents_index_list "$1" "$2" && return
    [ -s "$3" ] && __add_to_contents_index_list "$1" "$3" && return
}


# fills ALT_CONTENTS_INDEX_LIST
update_alt_contents_index()
{
    load_helper epm-repolist
    __init_contents_index_list
    # TODO: fix for Etersoft/LINUX@Etersoft
    # TODO: fix for rsync
    info "Retrieving contents_index ..."
    (quiet=1 epm_repolist) | grep -v " task$" | grep -E "rpm.*(ftp://|http://|https://|rsync://|file:/)" | sed -e "s@^rpm.*\(ftp://\|http://\|https://\)@rsync://@g" | sed -e "s@^rpm.*\(file:\)@@g" | while read -r URL1 URL2 component ; do
        [ "$component" = "debuginfo" ] && continue
        URL="$URL1/$URL2"
        if echo "$URL" | grep -q "^/" ; then
            # first check for local mirror
            local LOCALPATH="$(echo "$URL/base")"
            local LOCALPATHGZIP="$(echo "$LOCALPATH" | sed -e "s|/ALTLinux/|/ALTLinux/contents_index/|")"
            __add_better_to_contents_index_list "$URL" "$LOCALPATHGZIP/contents_index.gz" "$LOCALPATH/contents_index"
        else
            local LOCALPATH="$(get_local_alt_mirror_path "$URL")"
            local REMOTEURL="$(get_url_to_etersoft_mirror "$URL")"
            if [ -n "$REMOTEURL" ] ; then
                rsync_alt_contents_index $REMOTEURL/base/contents_index.gz $LOCALPATH/contents_index.gz && __add_to_contents_index_list "$REMOTEURL" "$LOCALPATH/contents_index.gz" && continue
                [ -n "$verbose" ] && info "Note: Can't retrieve $REMOTEURL/base/contents_index.gz, fallback to $URL/base/contents_index"
            fi
            # fix rsync URL firstly
            local RSYNCURL="$(echo "$URL" | sed -e "s|rsync://\(ftp.basealt.ru\|basealt.org\|altlinux.ru\)/pub/distributions/ALTLinux|rsync://\1/ALTLinux|")" #"
            rsync_alt_contents_index $RSYNCURL/base/contents_index $LOCALPATH/contents_index -z && __add_to_contents_index_list "$RSYNCURL" "$LOCALPATH/contents_index" && continue

            __add_better_to_contents_index_list "(cached)" "$LOCALPATH/contents_index.gz" "$LOCALPATH/contents_index"
        fi
    done
    if [ ! -s "$ALT_CONTENTS_INDEX_LIST" ] ; then
        fatal "Have no local contents index. Check epm repo --help."
    fi
}