#!/bin/bash

API_BASE_URL=https://labmanager-api.edu-al.unipmn.it/api/1.0

function getTokenJSON() {
    echo `curl -s -k --max-time 10 -X POST -H "Content-Type: application/json" -d "{\"login\":\"guest\",\"pwd\":\"\"}" ${API_BASE_URL}/login`
}


function jsonValue() {
    KEY=$1
    num=$2
    awk -F"[,:}]" '{for(i=1;i<=NF;i++){if($i~/\042'$KEY'\042/){print $(i+1)}}}' | tr -d '"' | sed -n ${num}p
}


stop() {
    echo "STOP ESAME-GET-CONFIG"
}


start() {
    echo "START ESAME-GET-CONFIG"

    TOKEN_JSON=$(getTokenJSON)
    TOKEN=`echo ${TOKEN_JSON} | jsonValue token 1`
    MACHINE_NAME=`hostname`
    MACHINE_JSON=`/usr/bin/curl -s -k --max-time 10 -H "Authorization: Bearer ${TOKEN}" -X GET ${API_BASE_URL}/machines/name/${MACHINE_NAME}`
    MACHINE_ID=`echo $MACHINE_JSON | jsonValue id 1`
    MACHINE_CONFIGS_ID=`echo $MACHINE_JSON | jsonValue configs_id 1`

    MACHINE_CONFIGS_ID_PREV=''
    if [[ -e /local/config_id ]]
    then
        MACHINE_CONFIGS_ID_PREV=`cat /local/config_id`
    fi

    echo "TOKEN_JSON: $TOKEN_JSON"
    echo "TOKEN: $TOKEN"
    echo "MACHINE_NAME: $MACHINE_NAME"
    echo "MACHINE_JSON: $MACHINE_JSON"
    echo "MACHINE_ID: $MACHINE_ID"
    echo "MACHINE_CONFIGS_ID: $MACHINE_CONFIGS_ID"
    echo "MACHINE_CONFIGS_ID_PREV: $MACHINE_CONFIGS_ID_PREV"

    # non sono riuscito a contattatare il ws
    if [[ "$MACHINE_CONFIGS_ID" == "" ]]
    then
        echo "Error: WS unreachable or wrong credentials"
        exit 1
    fi

    # back config files up
    cp -f /local/esame-machine.conf /local/esame-machine.conf.prev 2>&1
    cp -f /local/iptables /local/iptables.prev 2>&1

    # get configuration file
    HTTP_STATUS=`/usr/bin/curl -s -k -w "%{http_code}" -o /local/esame-machine.conf --max-time 10 --header "Authorization: Bearer ${TOKEN}" -X GET ${API_BASE_URL}/machines/${MACHINE_ID}/configfile`
    if [[ $HTTP_STATUS -ne 200 ]]
    then
        echo "Error downloading config file (http_status=$HTTP_STATUS)"
        exit 1
    else
        echo "Downloaded config file (http_status=$HTTP_STATUS)"
    fi

    # get ipconfig file
    HTTP_STATUS=`/usr/bin/curl -s -k -w "%{http_code}" -o /local/iptables --max-time 10 --header "Authorization: Bearer ${TOKEN}" -X GET ${API_BASE_URL}/machines/${MACHINE_ID}/ipconfigfile`
    if [[ $HTTP_STATUS -ne 200 ]]
    then
        echo "Error downloading iptables config file (http_status=$HTTP_STATUS)"
        exit 1
    else
        echo "Downloaded iptables config file (http_status=$HTTP_STATUS)"
    fi

    # configuration profile is changed
    if [[ "$MACHINE_CONFIGS_ID" != "$MACHINE_CONFIGS_ID_PREV" ]]
    then
        # update config_id file
        echo ${MACHINE_CONFIGS_ID} > /local/config_id

        # no exam, set normal target
        if [[ "$MACHINE_CONFIGS_ID" -eq "0" ]]
        then
            # stop the timer to avoid executing this script again
            /usr/bin/systemctl stop esame-apply-config.timer
            # stop some services to revert system files
            /usr/bin/systemctl stop esame-kioskmode
            /usr/bin/systemctl stop esame-kdm-autologin
            /usr/bin/systemctl stop esame-virtualbox
            rm /local/esame-machine.conf 2>&1
            rm /local/esame-machine.conf.prev 2>&1
            rm /local/iptables 2>&1
            rm /local/iptables.prev 2>&1
            echo "Normal!"
            /usr/bin/systemctl set-default graphical.target
            reboot
        else
            echo "Exam!"
            /usr/bin/systemctl stop esame-apply-config.timer
            /usr/bin/systemctl set-default esame.target
            reboot
        fi
    else
        # Update this machine's current config id
        HTTP_STATUS=`/usr/bin/curl -s -k -w "%{http_code}" -o /dev/null --max-time 10 -H "Content-Type: application/json" -H "Authorization: Bearer ${TOKEN}" \
            -X PUT -d "{\"current_configs_id\":\"$MACHINE_CONFIGS_ID\"}" ${API_BASE_URL}/machines/${MACHINE_ID}/currentconfig`

        if [[ $HTTP_STATUS -ne 200 ]]
        then
            echo "Error updating current config (http_status=$HTTP_STATUS)"
            exit 1
        else
            echo "Updated current config (http_status=$HTTP_STATUS)"
        fi
    fi

    # Runtime parameters
    if [[ "$MACHINE_CONFIGS_ID" -ne "0" ]]
    then
        # check if parameters are changed
        cmp --silent /local/esame-machine.conf /local/esame-machine.conf.prev
        if [[ $? -ne 0 ]]
        then
            /usr/bin/systemctl daemon-reload
            echo "Configuration parameters changed: restart some services... "
            # restart some exam services
            echo -n "USB..."
            /usr/bin/systemctl restart esame-usb
            echo " done."
            echo -n "Firefox home..."
            /usr/bin/systemctl restart esame-firefox-home
            echo " done."
            echo
            echo "All done."
        fi
    fi
}


args=("$@")

case "$1" in
'start')
    start
    ;;
'stop')
    stop
    ;;
'restart')
    stop
    start
    ;;
*)
    echo "Usage: $0 { start | stop | restart }";
    exit 1;
    ;;
esac
exit 0