#!/bin/bash

env_dir=$1
base_dir="$(dirname "$(realpath -s "$0")")"
root_dir="$base_dir/../../.."

[[ -z $env_dir ]] && env_dir="/etc/zio/backup"

function restic_exec() {
    command="$1"
    args="${@:2}"

    if [[ -z $command ]]; then
        say_warn "No command specified. Not running."
    else
        restic \
            --password-file "$passwd_file" \
            --repo "$repo" \
            $command $args
    fi
}

function backup() {
    path="$1"
    args="${@:2}"

    if [[ ! -d $path ]]; then
        warn "'$path' does not exist. Not backing up."
    else
        for exclude in "${excludes[@]}"
        do
            args+=" --iexclude \"$exclude\""
        done
    
        restic_exec \
            backup \
            --iexclude "__MACOSX" \
            --iexclude ".cache" \
            --iexclude ".DS_Store" \
            --iexclude "cache" \
            --iexclude "CachedData" \
            --iexclude "CachedExtensionVSIXs" \
            --iexclude "Code Cache" \
            --iexclude "GPUCache" \
            --iexclude "GrSharedCache" \
            --iexclude "ShaderCache" \
            --iexclude "system-cache" \
            --iexclude "thumbs.db" \
            --iexclude "tmp" \
            --exclude "containers/storage/overlay" \
            --exclude "containers/storage/overlay-containers" \
            --exclude "containers/storage/overlay-images" \
            --exclude "containers/storage/overlay-layers" \
            --exclude-if-present ".nobackup" \
            --host "$host" \
            $args "$path"
    fi
}

function forget() {
    path="$1"

    restic_exec \
        forget \
        --host "$host" \
        --keep-last 5 \
        --path "$path"
}

function get_prop() {
    file=$1
    item=$2
    echo $(grep -oP '(?<=^'"$item"'=).+' $file | tr -d '"')
}

function say() {
    message=$@
    echo -e "$@"
}

function say_die() {
    message=$@
    say "\033[1;31mError: $message\033[0m"
    exit 255
}

function say_do() {
    message=$@
    say "\033[1;34m$message\033[0m"
}

function say_warn() {
    message=$@
    say "\033[1;33mWarning: $message\033[0m"
}

function test_path() {
    prog=$@

    if [[ ! -x "$(command -v $prog)" ]]; then
        say_die "'$prog' is not installed (or not in \$PATH). Aborting..."
    fi
}

host="$(hostname -s)"
repo="b2:zio-euc-servers:/"

passwd_file="$env_dir/passwd"
pre_script_file="$env_dir/pre-script"
post_script_file="$env_dir/post-script"

b2_account_id=""
b2_account_key=""
excludes=()
paths=()
services=()

if [[ $UID != 0 ]]; then
    say_die "Unauthorized (are you root?)"
fi

if [[ ! -d $env_dir ]]; then
    say_die "Config directory ($env_dir) not found."
else
    chown root:root -R $env_dir
    chmod 660 -R $env_dir

    [[ -f "$env_dir/script-pre" ]] && pre_script="$env_dir/script-pre"
    [[ -f "$env_dir/script-post" ]] && post_script="$env_dir/script-post"

    if [[ -f "$env_dir/config" ]]; then
        [[ ! -z $(get_prop "$env_dir/config" B2_ACCOUNT_ID) ]] && \
            b2_account_id="$(get_prop "$env_dir/config" B2_ACCOUNT_ID)"
        [[ ! -z $(get_prop "$env_dir/config" B2_ACCOUNT_KEY) ]] && \
            b2_account_key="$(get_prop "$env_dir/config" B2_ACCOUNT_KEY)"
        [[ ! -z $(get_prop "$env_dir/config" EXCLUDES) ]] && \
            IFS=';' read -ra excludes <<< "$(get_prop "$env_dir/config" EXCLUDES)"
        [[ ! -z $(get_prop "$env_dir/config" PATHS) ]] && \
            IFS=';' read -ra paths <<< "$(get_prop "$env_dir/config" PATHS)"
        [[ ! -z $(get_prop "$env_dir/config" SERVICES) ]] && \
            IFS=';' read -ra services <<< "$(get_prop "$env_dir/config" SERVICES)"
    fi

    if [[ ! -f "$env_dir/passwd" ]]; then
        say_die "Password file ($passwd_file) not found."
    fi
fi

[[ -z $paths ]] && say_die "No paths specified. Aborting..."

if [[ -z $b2_account_id ]]; then
    say_die "B2_ACCOUNT_ID (in $env_dir/config) not set. Aborting..."
else
    export B2_ACCOUNT_ID="$b2_account_id"
fi

if [[ -z $b2_account_key ]]; then
    say_die "B2_ACCOUNT_KEY (in $env_dir/config) not set. Aborting..."
else
    export B2_ACCOUNT_KEY="$b2_account_key"
fi

if [[ -f $pre_script_file ]]; then
    say_do "Executing pre-backup script..."
    . $pre_script_file
fi

say_do "Stopping services..."
for service in "${services[@]}"
do
    systemctl stop $service
done

say_do "Backing up files..."
for path in "${paths[@]}"
do
    backup $path
done

say_do "Starting services..."
for service in "${services[@]}"
do
    systemctl start $service
done

if [[ -f $post_script_file ]]; then
    say_do "Executing post-backup script..."
    . $post_script_file
fi

say_do "Removing old backups..."
for path in "${paths[@]}"
do
    forget $path
done