# -*- mode: shell-script -*-


apache_proxy_dir () {
    DOMAIN=$(relation-get domain) || {
        err "You must specify a ${WHITE}domain$NORMAL option in relation."
        return 1
    }
    proxy=yes apache_vhost_create || return 1
    info "Added $DOMAIN as a proxy to $TARGET."
}
export -f apache_proxy_dir


apache_publish_dir () {
    DOMAIN=$(relation-get domain) || {
        err "You must specify a ${WHITE}domain$NORMAL option in relation."
        return 1
    }
    DOCKER_SITE_PATH="/var/www/${DOMAIN}"
    LOCATION=$(relation-get location 2>/dev/null) ||
        LOCATION="$DATASTORE/$BASE_SERVICE_NAME$DOCKER_SITE_PATH"

    apache_vhost_create || return 1
    info "Added $DOMAIN apache config."
    apache_code_dir || return 1
    apache_data_dirs

}
export -f apache_publish_dir


apache_vhost_create () {
    export APACHE_CONFIG_LOCATION="$SERVICE_CONFIGSTORE/etc/apache2/sites-enabled"
    export SERVER_ALIAS=$(relation-get server-aliases 2>/dev/null) || true

    export PROTOCOLS=$(__vhost_cfg_normalize_protocol) || return 1

    export SSL_PLUGIN_FUN=$(ssl_get_plugin_fun) || return 1
    if is_protocol_enabled https; then
        "$SSL_PLUGIN_FUN"_vars "$(relation-get ssl)" || return 1
    fi
    apache_vhost_statement "$PROTOCOLS" |
        file_put "$APACHE_CONFIG_LOCATION/$prefix$DOMAIN.conf" || return 1

    __vhost_cfg_creds_enabled=$(relation-get creds 2>/dev/null) || true
    if [ "$__vhost_cfg_creds_enabled" ]; then
        apache_passwd_file || return 1
    fi

    "$SSL_PLUGIN_FUN"_prepare "$(relation-get ssl)" || return 1
}


is_protocol_enabled() {
    local protocol=$1
    [[ "$PROTOCOLS" == *",$protocol,"* ]]
}
export -f is_protocol_enabled


__vhost_cfg_normalize_protocol() {
    local protocol

    if ! protocol=$(relation-get protocol 2>/dev/null); then
        protocol=auto
    else
        protocol=${protocol:-auto}
    fi

    case "$protocol" in
        auto)
            if __vhost_cfg_ssl="$(relation-get ssl 2>/dev/null)"; then
                protocol="https"
                export __vhost_cfg_ssl
            else
                protocol="http"
            fi
            ;;
        both)
            protocol="https,http"
            ;;
        ssl|https)
            protocol="https"
            ;;
        http)
            protocol="http"
            ;;
        *)
            err "Invalid value '$protocol' for ${WHITE}protocol$NORMAL option (use one of: http, https, both, auto)."
            return 1
    esac
    echo ",$protocol,"
}


## ssl_plugin_* and ssl_fallback should :
##  - do anything to ensure that 
##  - issue config-add to add volumes if necessary
##  - output 3 vars of where to find the 3 files from within the docker apache

ssl_get_plugin_fun() {
    local cfg="$(relation-get ssl 2>/dev/null)"
    if [[ "$(echo "$cfg" | shyaml get-type 2>/dev/null)" == "str" ]]; then
        target_relation=
        while read-0 relation_name target_service relation_config tech_dep; do
            [ "$target_service" == "$cfg" ] || continue
            verb "service ${DARKYELLOW}$target_service${NORMAL} matches" \
                  "${WHITE}ssl${NORMAL} value: candidate relation is ${DARKBLUE}$relation_name${NORMAL}"
            fun="ssl_plugin_${relation_name}"
            if declare -F "${fun}_vars" >/dev/null 2>&1 && declare -F "${fun}_prepare" >/dev/null 2>&1; then
                verb "Corresponding plugin ${DARKGREEN}found${NORMAL} for relation ${DARKBLUE}$relation_name${NORMAL}"
                echo "$fun"
                return 0
            else
                verb "Corresponding plugin ${DARKRED}not found${NORMAL} for relation ${DARKBLUE}$relation_name${NORMAL}"
            fi
        done < <(get_compose_relations "$SERVICE_NAME") || return 1
        err "Invalid ${WHITE}ssl${NORMAL} value: '$cfg' is not a valid linked service through a support relation."
        return 1
    else
        echo ssl_fallback
    fi
}


ssl_fallback_vars() {
    local cfg="$1" cert key ca_cert

    if __vhost_cfg_ssl_cert=$(echo "$cfg" | shyaml get-value cert 2>/dev/null); then
        __vhost_cfg_SSL_CERT_LOCATION=/etc/ssl/certs/${DOMAIN}.pem
    fi

    if __vhost_cfg_ssl_key=$(echo "$cfg" | shyaml get-value key 2>/dev/null); then
        __vhost_cfg_SSL_KEY_LOCATION=/etc/ssl/private/${DOMAIN}.key
    fi

    if __vhost_cfg_ssl_ca_cert=$(echo "$cfg" | shyaml get-value ca-cert 2>/dev/null); then
        __vhost_cfg_SSL_CA_CERT_LOCATION=/etc/ssl/certs/${DOMAIN}-ca.pem
    fi
}

ssl_fallback_prepare() {
    local cfg="$1" cert key ca_cert

    dst="$CONFIGSTORE/$BASE_SERVICE_NAME"
    volumes=""
    for label in cert key ca_cert; do
        content="$(eval echo "\"\$__vhost_cfg_ssl_$label\"")"
        if [ "$content" ]; then
            location="$(eval echo "\$__vhost_cfg_SSL_${label^^}_LOCATION")"
            echo "$content" | file_put "$dst$location"
            volumes="$volumes
      - $dst$location:$location:ro"
        fi
    done

    if [ "$volumes" ]; then
        config-add "\
services:
  $MASTER_TARGET_SERVICE_NAME:
    volumes:
$volumes
"
    fi

}

ssl_plugin_letsencrypt-dns_vars() {

    __vhost_cfg_SSL_CERT_LOCATION=/etc/letsencrypt/live/${DOMAIN}/cert.pem
    __vhost_cfg_SSL_KEY_LOCATION=/etc/letsencrypt/live/${DOMAIN}/privkey.pem
    __vhost_cfg_SSL_CHAIN=/etc/letsencrypt/live/${DOMAIN}/chain.pem
}

ssl_plugin_letsencrypt-dns_prepare() {
    local service="$1" letsencrypt_charm
    shift

    export DEFAULT_COMPOSE_FILE="$COMPOSE_YML_FILE"
    run_service_action "$service" add "$DOMAIN" $(echo "$SERVER_ALIAS" | shyaml get-values 2>/dev/null) || return 1
    letsencrypt_charm=$(get_service_charm "$service") || return 1

    config-add "\
services:
  $MASTER_TARGET_SERVICE_NAME:
    volumes:
      - $DATASTORE/${letsencrypt_charm}/etc/letsencrypt:/etc/letsencrypt:ro
" || return 1

}


apache_passwd_file() {
    include parse || true

    ## XXXvlab: called twice... no better way to do this ?
    __vhost_creds_statement >/dev/null
    first=
    if ! [ -e "$CONFIGSTORE/$MASTER_TARGET_SERVICE_NAME$password_file" ]; then
        debug "No file $CONFIGSTORE/$MASTER_TARGET_SERVICE_NAME$password_file, creating password file." || true
        first=c
    fi
    while read-0 login password; do
        debug "htpasswd -b$first '${password_file}' '$login' '$password'"
        echo "htpasswd -b$first '${password_file}' '$login' '$password'"
        if [ "$first" ]; then
            first=
        fi
    done < <(echo "$__vhost_cfg_creds_enabled" | shyaml key-values-0 2>/dev/null) |
        docker run -i --entrypoint "/bin/bash" \
               -v "$APACHE_CONFIG_LOCATION:/etc/apache2/sites-enabled" \
               "$DOCKER_BASE_IMAGE" || return 1
}

## Produce the full statements depending on relation-get informations
apache_vhost_statement() {
    local vhost_statement
    export SERVER_ALIAS=$(relation-get server-aliases 2>/dev/null) || true
    export PROTOCOLS="$1"

    if is_protocol_enabled http; then
        __vhost_full_vhost_statement http
    fi
    if is_protocol_enabled https; then
        export SSL_PLUGIN_FUN=$(ssl_get_plugin_fun) || return 1
        "$SSL_PLUGIN_FUN"_vars "$(relation-get ssl 2>/dev/null)"
        cat <<EOF

<IfModule mod_ssl.c>
$(__vhost_full_vhost_statement https | prefix "  ")
</IfModule>
EOF
    fi
}
export -f apache_vhost_statement


apache_code_dir() {
    local www_data_gid
    www_data_gid=$(cached_cmd_on_base_image apache 'id -g www-data') || {
        debug "Failed to query for www-data gid in ${DARKYELLOW}apache${NORMAL} base image."
        return 1
    }

    mkdir -p "$LOCATION" || return 1
    setfacl -R -m g:"$www_data_gid":rx "$LOCATION"
    info "Set permission for read and traversal on '$LOCATION'."

    config-add "
$MASTER_BASE_SERVICE_NAME:
  volumes:
    - $LOCATION:$DOCKER_SITE_PATH
"
}

apache_data_dirs() {

    DATA_DIRS=$(relation-get data-dirs 2>/dev/null | shyaml get-values 2>/dev/null) || true
    if [ -z "$DATA_DIRS" ]; then
        return 0
    fi

    DST=$DATASTORE/$BASE_SERVICE_NAME$DOCKER_SITE_PATH
    DATA=()
    while IFS="," read -ra ADDR; do
        for dir in "${ADDR[@]}"; do
            DATA+=($dir)
        done
    done <<< "$DATA_DIRS"

    www_data_gid=$(cached_cmd_on_base_image apache 'id -g www-data') || {
        debug "Failed to query for www-data gid in ${DARKYELLOW}apache${NORMAL} base image."
        return 1
    }
    info "www-data gid from ${DARKYELLOW}apache${NORMAL} is '$www_data_gid'" 

    dirs=()
    for d in "${DATA[@]}"; do
        dirs+=("$DST/$d")
    done

    mkdir -p "${dirs[@]}"
    setfacl -R -m g:"$www_data_gid":rwx "${dirs[@]}"
    setfacl -R -d -m g:"$www_data_gid":rwx "${dirs[@]}"

    config-add "
$MASTER_BASE_SERVICE_NAME:
  volumes:
$(
    for d in "${DATA[@]}"; do
        echo "    - $DST/$d:$DOCKER_SITE_PATH/$d"
    done
)"

}

deploy_files() {
    local src="$1" dst="$2"

    if ! [ -d "$dst" ]; then
        err "Destination '$dst' does not exist or is not a directory"
        return 1
    fi
    (
        cd "$dst" && info "In $dst:" &&
        get_file "$src" | tar xv
    )
}
export -f deploy_files


apache_core_rules_add() {
    local conf="$1" dst="/etc/apache2/conf-enabled/$BASE_SERVICE_NAME.conf"
    debug "Adding core rule."
    echo "$conf" | file_put "$CONFIGSTORE/$BASE_SERVICE_NAME$dst"
    config-add "
$MASTER_BASE_SERVICE_NAME:
  volumes:
    - $CONFIGSTORE/$BASE_SERVICE_NAME$dst:$dst:ro
"
}


__vhost_ssl_statement() {

    ## defaults

    __vhost_cfg_SSL_CERT_LOCATION=${__vhost_cfg_SSL_CERT_LOCATION:-/etc/ssl/certs/ssl-cert-snakeoil.pem}
    __vhost_cfg_SSL_KEY_LOCATION=${__vhost_cfg_SSL_KEY_LOCATION:-/etc/ssl/private/ssl-cert-snakeoil.key}

    cat <<EOF

##
## SSL Configuration
##

SSLEngine On

SSLCertificateFile $__vhost_cfg_SSL_CERT_LOCATION
SSLCertificateKeyFile $__vhost_cfg_SSL_KEY_LOCATION
$([ -z "$__vhost_cfg_SSL_CA_CERT_LOCATION" ] || echo "SSLCACertificateFile $__vhost_cfg_SSL_CA_CERT_LOCATION")
$([ -z "$__vhost_cfg_SSL_CHAIN" ] || echo "SSLCertificateChainFile $__vhost_cfg_SSL_CHAIN")
SSLVerifyClient None

EOF

}


__vhost_creds_statement() {
    if ! __vhost_cfg_creds_enabled=$(relation-get creds 2>/dev/null); then
        echo "Allow from all"
        return 0
    fi

    password_file=/etc/apache2/sites-enabled/${DOMAIN}.passwd

    cat <<EOF
AuthType basic
AuthName "private"
AuthUserFile ${password_file}
Require valid-user
EOF

}


__vhost_head_statement() {
    local protocol="$1"

    if [ "$protocol" == "https" ]; then
        prefix="s-"
    else
        prefix=
    fi

    cat <<EOF
ServerAdmin ${ADMIN_MAIL:-contact@$DOMAIN}
ServerName ${DOMAIN}
$(
  while read-0 alias; do
      echo "ServerAlias $alias"
  done < <(echo "$SERVER_ALIAS" | shyaml get-values-0 2>/dev/null)
)
ServerSignature Off
CustomLog /var/log/apache2/${prefix}${DOMAIN}_access.log combined
ErrorLog /var/log/apache2/${prefix}${DOMAIN}_error.log
ErrorLog syslog:local2
EOF

}


__vhost_custom_rules() {
    local custom_rules
    if custom_rules=$(relation-get apache-custom-rules 2>/dev/null); then
        cat <<EOF


##
## Custom rules
##

$custom_rules

EOF
    fi
}


__vhost_content_statement() {
    if [ "$proxy" ]; then
        __vhost_proxy_statement "$@"
    else
        __vhost_publish_dir_statement "$@"
    fi
}


__vhost_proxy_statement() {
    local protocol="$1"

    TARGET=$(relation-get target 2>/dev/null) || true
    if [ -z "$TARGET" ]; then
        ## First exposed port:
        base_image=$(service_base_docker_image "$BASE_SERVICE_NAME") || return 1
        first_exposed_port=$(image_exposed_ports_0 "$base_image" | tr '\0' '\n' | head -n 1 | cut -f 1 -d /) || return 1
        TARGET=$MASTER_BASE_SERVICE_NAME:$first_exposed_port
        info "No target was specified, introspection found: $TARGET"
    fi

    cat <<EOF

##
## Proxy declaration towards $TARGET
##

<IfModule mod_proxy.c>
    ProxyRequests Off
    <Proxy *>
        Order deny,allow
        Allow from all
    </Proxy>
    ProxyVia On
    ProxyPass / http://$TARGET/ retry=0
    <Location / >
$(__vhost_creds_statement | prefix "        ")
        ProxyPassReverse /
    </Location>
$([ "$protocol" == "https" ] && echo "    SSLProxyEngine On")
</IfModule>

RequestHeader set "X-Forwarded-Proto" "$protocol"

## Fix IE problem (httpapache proxy dav error 408/409)
SetEnv proxy-nokeepalive 1
EOF

}

__vhost_full_vhost_statement() {
    local protocol="$1"

    case "$protocol" in
        https)
            PORT=443
            ;;
        http)
            PORT=80
            ;;
    esac

    cat <<EOF
<VirtualHost *:$PORT>

$(__vhost_head_statement "$protocol" | prefix "    " && echo)
$(__vhost_custom_rules | prefix "    " && echo)
$(__vhost_content_statement "$protocol" | prefix "    ")

    ## Forbid any cache, this is only usefull on dev server.
    #Header set Cache-Control "no-cache"
    #Header set Access-Control-Allow-Origin "*"
    #Header set Access-Control-Allow-Methods "POST, GET, OPTIONS"
    #Header set Access-Control-Allow-Headers "origin, content-type, accept"
$([ "$protocol" == "https" ] && __vhost_ssl_statement | prefix "    " && echo )
</VirtualHost>
EOF

}

__vhost_publish_dir_statement() {
    cat <<EOF
##
## Publish directory $DOCKER_SITE_PATH
##

DocumentRoot $DOCKER_SITE_PATH

<Directory />
    Options FollowSymLinks
    AllowOverride None
</Directory>

<Directory $DOCKER_SITE_PATH>
    Options Indexes FollowSymLinks MultiViews
    AllowOverride all
$(__vhost_creds_statement | prefix "    ")
</Directory>

EOF
}


apache_config_hash() {
    debug "Adding config hash to enable recreating upon config change."
    config_hash=$(find "$SERVICE_CONFIGSTORE/etc/apache2/sites-enabled" \
                       -name \*.conf -exec md5sum {} \; | md5_compat) || exit 1
    init-config-add "
$MASTER_BASE_SERVICE_NAME:
  labels:
    - compose.config_hash=$config_hash
"
}