#!/bin/bash

DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"

seconds_to_wait=3600
ACME_CA_URI="${ACME_CA_URI:-https://acme-v01.api.letsencrypt.org/directory}"
ACME_TOS_HASH="${ACME_TOS_HASH:-6373439b9f29d67a5cd4d18cbc7f264809342dbf21cb2ba2fc7588df987a6221}"
DEFAULT_KEY_SIZE=4096

source /app/functions.sh

create_link() {
    local readonly target=${1?missing target argument}
    local readonly source=${2?missing source argument}
    [[ -f "$target" ]] && return 1
    ln -sf "$source" "$target"
}

create_links() {
    local readonly base_domain=${1?missing base_domain argument}
    local readonly domain=${2?missing base_domain argument}

    if [[ ! -f "/etc/nginx/certs/$base_domain"/fullchain.pem || \
          ! -f "/etc/nginx/certs/$base_domain"/key.pem ]]; then
        return 1
    fi
    local return_code=1
    create_link "/etc/nginx/certs/$domain".crt "./$base_domain"/fullchain.pem
    return_code=$(( $return_code & $? ))
    create_link "/etc/nginx/certs/$domain".key "./$base_domain"/key.pem
    return_code=$(( $return_code & $? ))
    if [[ -f "/etc/nginx/certs/dhparam.pem" ]]; then
        create_link "/etc/nginx/certs/$domain".dhparam.pem ./dhparam.pem
        return_code=$(( $return_code & $? ))
    fi
    if [[ -f "/etc/nginx/certs/$base_domain"/chain.pem ]]; then
        create_link "/etc/nginx/certs/$domain".chain.pem "./$base_domain"/chain.pem
        return_code=$(( $return_code & $? ))
    fi
    return $return_code
}

update_certs() {
    [[ ! -f "$DIR"/letsencrypt_service_data ]] && return

    # Load relevant container settings
    unset LETSENCRYPT_CONTAINERS
    source "$DIR"/letsencrypt_service_data

    reload_nginx='false'
    for cid in "${LETSENCRYPT_CONTAINERS[@]}"; do
        # Derive host and email variable names
        host_varname="LETSENCRYPT_${cid}_HOST"
        # Array variable indirection hack: http://stackoverflow.com/a/25880676/350221
        hosts_array=$host_varname[@]
        email_varname="LETSENCRYPT_${cid}_EMAIL"

        keysize_varname="LETSENCRYPT_${cid}_KEYSIZE"
        cert_keysize="${!keysize_varname}"
        if [[ "$cert_keysize" == "<no value>" ]]; then
            cert_keysize=$DEFAULT_KEY_SIZE
        fi

        test_certificate_varname="LETSENCRYPT_${cid}_TEST"
        create_test_certificate=false
        if [[ $(lc "${!test_certificate_varname:-}") == true ]]; then
            create_test_certificate=true
        fi

        params_d_str=""
        [[ $DEBUG == true ]] && params_d_str+=" -v"

        hosts_array_expanded=("${!hosts_array}")
        # First domain will be our base domain
        base_domain="${hosts_array_expanded[0]}"

        if [[ "$create_test_certificate" == true ]]; then
            # Use staging acme end point
            acme_ca_uri="https://acme-staging.api.letsencrypt.org/directory"
            if [[ ! -f /etc/nginx/certs/.${base_domain}.test ]]; then
                # Remove old certificates
                rm -rf /etc/nginx/certs/${base_domain}
                for domain in "${!hosts_array}"; do
                    rm -f /etc/nginx/certs/$domain.{crt,key,dhparam.pem}
                done
                touch /etc/nginx/certs/.${base_domain}.test
            fi
        else
            acme_ca_uri="$ACME_CA_URI"
            if [[ -f /etc/nginx/certs/.${base_domain}.test ]]; then
                # Remove old test certificates
                rm -rf /etc/nginx/certs/${base_domain}
                for domain in "${!hosts_array}"; do
                    rm -f /etc/nginx/certs/$domain.{crt,key,dhparam.pem}
                done
                rm -f /etc/nginx/certs/.${base_domain}.test
            fi
        fi

        # Create directory for the first domain
        mkdir -p /etc/nginx/certs/$base_domain
        cd /etc/nginx/certs/$base_domain

        for domain in "${!hosts_array}"; do
            # Add all the domains to certificate
            params_d_str+=" -d $domain"
            # Add location configuration for the domain
            add_location_configuration "$domain" || reload_nginx
        done

        echo "Creating/renewal $base_domain certificates... (${hosts_array_expanded[*]})"
        /usr/bin/simp_le \
            -f account_key.json -f key.pem -f chain.pem -f fullchain.pem -f cert.pem \
            --tos_sha256 $ACME_TOS_HASH \
            $params_d_str \
            --cert_key_size=$cert_keysize \
            --email "${!email_varname}" \
            --server=$acme_ca_uri \
            --default_root /usr/share/nginx/html/

        simp_le_return=$?

        for altnames in ${hosts_array_expanded[@]:1}; do
            # Remove old CN domain that now are altnames
            rm -rf /etc/nginx/certs/$altnames
        done

        if [[ -z $base_domain ]]; then
            echo "inavalid stuff from container: ${cid}"
        fi
        if [[ ! -z $base_domain ]]; then

            for domain in "${!hosts_array}"; do
                create_links $base_domain $domain && reload_nginx='true'
                [[ $simp_le_return -eq 0 ]] && reload_nginx='true'
            done
        fi

    done

    [[ "$reload_nginx" == 'true' ]] && reload_nginx
}

pid=
# Service Loop: When this script exits, start it again.
trap '[[ $pid ]] && kill $pid; exec $0' EXIT
trap 'trap - EXIT' INT TERM

update_certs

# Wait some amount of time
echo "Sleep for ${seconds_to_wait}s"
sleep $seconds_to_wait & pid=$!
wait
pid=