API_TOKEN="${API_TOKEN:-ABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890abcd}"
ZONE="${ZONE:-example.com}"
DOMAIN="${DOMAIN:-example.com}"

EVENT() {
    printf "\x1b[95m>>> \x1b[0m\x1b[98m$1\n"
}

LOG() {
    printf "\x1b[98m$1\n"
}

ERROR() {
    >&2 printf "\x1b[91mError: \x1b[0m\x1b[98m$1\n"
}

CURL() {
    RESPONSE=$(curl --silent --request $1 \
    --url "https://api.cloudflare.com/client/v4$2" \
    --header "Content-Type: application/json" \
    --header "Authorization: Bearer $API_TOKEN" \
    --data "$3")
    SUCCESS=$(echo $RESPONSE | jq -r ".success")
    if [ "$SUCCESS" != "true" ]; then
        ERROR "$(echo $RESPONSE | jq -r ".errors[0].message")"
        kill $$
    fi

    echo $RESPONSE | jq ".result"
}

PATCH() {
    CURL "PATCH" "$1" "$2"
}

POST() {
    CURL "POST" "$1" "$2"
}

GET() {
    CURL "GET" "$1" ""
}

EVENT "Getting Zones"
ZONES=$(GET "/zones")
ZONE_ID="null"

i=0
while true; do

    ZONE_JSON=$(echo $ZONES | jq ".[$i]")

    if [ "$ZONE_JSON" == "null" ]; then
        break
    fi

    NAME=$(echo $ZONE_JSON | jq -r ".name")
    ID=$(echo $ZONE_JSON | jq -r ".id")

    LOG "Found Zone $NAME ($ID)"

    if [ "$NAME" == "$ZONE" ]; then
        ZONE_ID=$ID
        break
    fi

    ((i=i+1))

done

if [ "$ZONE_ID" == "null" ]; then
    ERROR "Could not find zone $DOMAIN"
    exit 1
fi  

EVENT "Getting Records"

RECORDS=$(GET "/zones/$ZONE_ID/dns_records")

IPv4Current="null"
IPv6Current="null"
IPv4Id="null"
IPv6Id="null"

i=0
while true; do
    
    RECORD=$(echo $RECORDS | jq ".[$i]")

    if [ "$RECORD" == "null" ]; then
        break
    fi

    NAME=$(echo $RECORD | jq -r '.name')
    TYPE=$(echo $RECORD | jq -r '.type')
    CONTENT=$(echo $RECORD | jq -r '.content')
    ID=$(echo $RECORD | jq -r '.id')

    LOG "Found record $NAME $TYPE \"$CONTENT\" ($ID)"

    if [ "$NAME" == "$DOMAIN" ] && [ "$TYPE" == "A" ]; then
        IPv4Current="$CONTENT"
        IPv4Id="$ID"
    fi

    if [ "$NAME" == "$DOMAIN" ] && [ "$TYPE" == "AAAA" ]; then
        IPv6Current="$CONTENT"
        IPv6Id="$ID"
    fi

    ((i=i+1))

done

EVENT "Getting current IPs"

IPv4New=$(curl ip.me -4sL --silent)
LOG "Using IPv4 $IPv4New"

IPv6New=$(curl ip.me -6sL --silent)
LOG "Using IPv6 $IPv6New"

UPDATE() {
    PATCH "/zones/$ZONE_ID/dns_records/$1" "$2" > /dev/null
}

CREATE() {
    POST "/zones/$ZONE_ID/dns_records" "$1" > /dev/null
}

IPv4JSON="{
    \"content\": \"$IPv4New\",
    \"name\": \"$DOMAIN\",
    \"proxied\": false,
    \"type\": \"A\"
}"

IPv6JSON="{
    \"content\": \"$IPv6New\",
    \"name\": \"$DOMAIN\",
    \"proxied\": false,
    \"type\": \"AAAA\"
}"

EVENT "Updating Records"

if [ "$IPv4Id" == "null" ]; then
    LOG "No IPv4 record found... creating new one"
    CREATE "$IPv4JSON"
elif [ "$IPv4Current" != "$IPv4New" ]; then
    LOG "IPv4 record found... updating"
    UPDATE "$IPv4Id" "$IPv4JSON"
else
    LOG "IPv4 is up to date... skipping"
fi

if [ "$IPv6Id" == "null" ]; then
    LOG "No IPv6 record found... creating new one"
    CREATE "$IPv6JSON"
elif [ "$IPv6Current" != "$IPv6New" ]; then
    LOG "IPv6 record found... updating"
    UPDATE "$IPv6Id" "$IPv6JSON"
else
    LOG "IPv6 is up to date... skipping"
fi

EVENT "Successfully updated records"