#!/bin/bash

RSYNC_KEY_PATH=/etc/rsync/keys


ANSI_ESC=$'\e['

NORMAL="${ANSI_ESC}0m"

GRAY="${ANSI_ESC}1;30m"
RED="${ANSI_ESC}1;31m"
GREEN="${ANSI_ESC}1;32m"
YELLOW="${ANSI_ESC}1;33m"
BLUE="${ANSI_ESC}1;34m"
PINK="${ANSI_ESC}1;35m"
CYAN="${ANSI_ESC}1;36m"
WHITE="${ANSI_ESC}1;37m"

DARKGRAY="${ANSI_ESC}0;30m"
DARKRED="${ANSI_ESC}0;31m"
DARKGREEN="${ANSI_ESC}0;32m"
DARKYELLOW="${ANSI_ESC}0;33m"
DARKBLUE="${ANSI_ESC}0;34m"
DARKPINK="${ANSI_ESC}0;35m"
DARKCYAN="${ANSI_ESC}0;36m"
DARKWHITE="${ANSI_ESC}0;37m"


ssh-key-ls() {
    local label="$1" f content
    for f in "${RSYNC_KEY_PATH}"/backup/"$label"/*.pub; do
        [ -e "$f" ] || continue
        ident=${f##*/}
        ident=${ident%.pub}
        content=$(cat "$f")
        key=${content#* }
        key=${key% *}
        printf "${DARKGRAY}..${NORMAL}%24s ${DARKCYAN}%s${NORMAL}\n" "${key: -24}" "$ident"
    done
}


ssh-key-rm() {
    local label="$1" ident="$2" delete

    delete="${RSYNC_KEY_PATH}/backup/$label/$ident.pub"
    if ! [ -e "$delete" ]; then
        echo "Error: key '$ident' not found." >&2
        return 1
    fi
    rm "$delete"

    /usr/local/sbin/ssh-update-keys
}


ssh-key-add() {
    local label="$1" type="$2" key="$3" email="$4"

    [ "$type" == "ssh-rsa" ] || {
        echo "Error: expecting ssh-rsa key type" >&2
        return 1
    }

    ## ident are unique by construction (they are struct keys)
    ## but keys need to be also unique
    declare -A keys
    mkdir -p "${RSYNC_KEY_PATH}/backup/$label"
    content="$type $key $email"
    ident="${email##*@}"
    target="${RSYNC_KEY_PATH}/backup/$label/$ident.pub"
    if [ -e "$target" ]; then
        old_content=$(cat "$target")
        if [ "$content" == "$old_content" ]; then
            echo "Provided key already present for '$ident'." >&2
            return 0
        fi
        echo "Replacing key for '$ident'." >&2
    elif [ -e "${RSYNC_KEY_PATH}/backup/"*"/$ident.pub" ]; then
        echo "ident '$ident' is already reserved, please pick another one." >&2
        return 1
    fi
    echo "$content" > "$target"

    /usr/local/sbin/ssh-update-keys
}




case "$1" in
    "add")
        shift
        ssh-key-add "$@"
        ;;
    "rm")
        shift
        ssh-key-rm "$@"
        ;;
    "ls")
        shift
        ssh-key-ls "$@"
        ;;
    *)
        echo "Unknown command '$1'."
        ;;
esac