#!/bin/bash

# Internal Initialization

source "${DIP_FUNCTIONS}"

if [[ -r "${DIP_BASE_DIR}/conf.d/${DIP_AGENT_NAME}.conf" ]]; then
    source "${DIP_BASE_DIR}/conf.d/${DIP_AGENT_NAME}.conf"
fi

if [[ -r "${DIP_BASE_DIR}/conf.d/${DIP_AGENT_EXEC}.conf" ]]; then
    source "${DIP_BASE_DIR}/conf.d/${DIP_AGENT_EXEC}.conf"
fi

if [[ -z "$agent_update_dns_linode_v4_token" ]]; then
    logerr "ERROR: Need 'agent_update_dns_linode_v4_token' to be defined to your Linode API Access Token"
    exit 99
fi

# Get Domain Name

_update_dns_linode_v4_get_domain() {
    local domain_id
    local response
    local page
    local total_pages
    local i=2
    local p=1

    while read -r response
    do
        if [[ -n "$(echo "$response" | jq 'select(.errors != null)')" ]]
        then
            return 1
        fi

        page=$(echo "$response" | jq ".page")
        total_pages=$(echo "$response" | jq ".pages")

        domain_id="$(sed -e 's/^"//' -e 's/"$//' <<<"$(echo "$response" | jq --arg domain "$DIP_RECORD" '.data[] | select(.domain==$domain).id')")"
        if [[ -n "$domain_id" ]]
        then
            _sub_domain=""
            _domain=$DIP_RECORD
            _domain_id=$domain_id
            return 0
        fi

        while true
        do
            h=$(printf "%s" "$DIP_RECORD" | cut -d . -f $i-100)

            if [[ -z "$h" ]]
            then
                return 1
            fi

            domain_id="$(sed -e 's/^"//' -e 's/"$//' <<<"$(echo "$response" | jq --arg domain "$h" '.data[] | select(.domain==$domain).id')")"

            if [[ -n "$domain_id" ]]
            then
                _sub_domain=$(printf "%s" "$DIP_RECORD" | cut -d . -f-$p)
                _domain=$h
                _domain_id=$domain_id
                return 0
            fi
            p=$i
            (( i++ )) || true
        done

        if [[ $page -ge $total_pages ]]
        then
            return 1
        fi
    done <<< "$(curl --silent -X GET -H "Content-Type: application/json" -H "Authorization: Bearer $agent_update_dns_linode_v4_token" "https://api.linode.com/v4/domains/")"    
    return 1
}

_update_dns_linode_v4_get_record_id() {
    local domain=$1
    local dtype=$2
    local subdomain=$3
    local response
    local record_id

    #if [[ "${#subdomain}" -gt "${#domain}" ]]; then
    #    subdomain="${subdomain:0:${#subdomain}-${#domain}-1}"
    #else
    #    subdomain="@"
    #fi

    response=$(curl \
        --silent \
        -X GET \
        -H "Content-Type: application/json" \
        -H "Authorization: Bearer $agent_update_dns_linode_v4_token" \
        "https://api.linode.com/v4/domains/$domain/records")
    
    #sed -e 's/^"//' -e 's/"$//' <<<"$(echo "$response" | jq ".domain_names[].name" )"
    record_id="$(echo "$response" | jq --arg subdomain "$subdomain" --arg dtype "$dtype" '.data[] | select(.name==$subdomain and .type==$dtype).id')"

    if [[ -z "$record_id" ]]
    then
        return 1
    else
        _record_id=$record_id
        return 0
    fi
}

if _update_dns_linode_v4_get_domain; then
    if valid_ipv4 "$DIP_CUR_IP"; then
        log "Updating Linode DNS IPv4 Record: ${DIP_RECORD} to ${DIP_CUR_IP}"

        if _update_dns_linode_v4_get_record_id "$_domain_id" "A" "$_sub_domain"
        then
            curl --silent \
                -X PUT \
                -H "Content-Type: application/json" \
                -H "Authorization: Bearer $agent_update_dns_linode_v4_token" \
                -d '{"target":"'$DIP_CUR_IP'"}' \
                "https://api.linode.com/v4/domains/$_domain_id/records/$_record_id" > /dev/null;
        else
            logerr "WARN: No A record exists for $DIP_RECORD"
        fi
    fi

    if valid_ipv6 "$DIP_CUR_IP"; then
        log "Updating Linux DNS IPv6 Record: ${DIP_RECORD} to ${DIP_CUR_IP}"

        if _update_dns_linode_v4_get_record_id "$_domain_id" "AAAA" "$_sub_domain"
        then
            curl --silent \
                -X PUT \
                -H "Content-Type: application/json" \
                -H "Authorization: Bearer $agent_update_dns_linode_v4_token" \
                -d '{"target":"'$DIP_CUR_IP'"}' \
                "https://api.linode.com/v4/domains/$_domain_id/records/$_record_id" > /dev/null;
        else
            logerr "WARN: No AAAA record exists for $DIP_RECORD"
        fi
    fi
else
    logerr "ERROR: Cannot find domain in Linode DNS API"
    exit 99
fi