#!/usr/bin/env bash
# {{ ansible_managed }}

set -x

function insert_host_entry {
    ENTRY=$1
    ADDR=$2
    if [[ "$(grep "^${ADDR}\b" /etc/hosts | wc -l)" -ge "2" ]]; then
      sed -i "/^${ADDR}\b/d" /etc/hosts
      echo "${ENTRY}" | tee -a /etc/hosts
    elif grep -q "^${ADDR}\b" /etc/hosts; then
      sed -i "s|^${ADDR}\b\ .*|${ENTRY}|" /etc/hosts
    elif ! grep -q "^${ENTRY}$" /etc/hosts; then
      echo "${ENTRY}" | tee -a /etc/hosts
    fi
}

function host_update {
    ANSHOSTNAME=$1
    RFCHOSTNAME=$2
    INVHOSTNAME=$3
    IPADDR=$4
    DOMAINNAME=$5

    if [[ "${ANSHOSTNAME}" != "${RFCHOSTNAME}" ]] && [[ "${RFCHOSTNAME}" != "${INVHOSTNAME}" ]]; then
        insert_host_entry "${IPADDR} ${RFCHOSTNAME}.${DOMAINNAME} ${RFCHOSTNAME} ${INVHOSTNAME} ${ANSHOSTNAME}" "${IPADDR}"
    elif [[ "${ANSHOSTNAME}" != "${RFCHOSTNAME}" ]] && [[ "${RFCHOSTNAME}" == "${INVHOSTNAME}" ]]; then
        insert_host_entry "${IPADDR} ${RFCHOSTNAME}.${DOMAINNAME} ${RFCHOSTNAME} ${ANSHOSTNAME}" "${IPADDR}"
    elif [[ "${ANSHOSTNAME}" == "${RFCHOSTNAME}" ]] && [[ "${RFCHOSTNAME}" == "${INVHOSTNAME}" ]]; then
        insert_host_entry "${IPADDR} ${RFCHOSTNAME}.${DOMAINNAME} ${RFCHOSTNAME}" "${IPADDR}"
    else
        insert_host_entry "${IPADDR} ${RFCHOSTNAME}.${DOMAINNAME} ${RFCHOSTNAME} ${INVHOSTNAME}" "${IPADDR}"
    fi
}

{% raw -%}
{% set host_rfc_1034_1035_name = inventory_hostname|replace('_', '-') %}
host_update "{{ ansible_hostname|default(host_rfc_1034_1035_name) }}" \
            "{{ host_rfc_1034_1035_name }}" \
            "{{ inventory_hostname }}" \
            "127.0.1.1" \
            "{{ openstack_domain }}"
{% endraw %}

{% for item in groups['all'] %}
{% set target_rfc_1034_1035_name = item|replace('_', '-') %}
host_update "{{ hostvars[item]['ansible_hostname']|default(target_rfc_1034_1035_name) }}" \
            "{{ target_rfc_1034_1035_name }}" \
            "{{ item }}" \
            "{{ hostvars[item]['ansible_host'] | default("127.0.0.1") }}" \
            "{{ openstack_domain }}"

{% endfor %}

md5sum /etc/hosts|awk '{print $1}'