#!/usr/bin/env bash

source $(dirname $0)/oref0-bash-common-functions.sh || (echo "ERROR: Failed to run oref0-bash-common-functions.sh. Is oref0 correctly installed?"; exit 1)

usage "$@" <<EOT
Usage: $self
Attempt to get a working internet connection via wifi or bluetooth. Typically
run from crontab.
EOT

hci_adapter=$(get_pref_string .bt_hci 2>/dev/null) || hci_adapter=0

hci_address=$(hciconfig hci${hci_adapter} | grep Address | cut -d' ' -f 3)

main() {
    MACs=$@
    HostAPDIP='10.29.29.1'
    echo; echo Starting oref0-online at $(date).
    # if we are connected to wifi but don't have an IP, try to get one
    if iwgetid -r wlan0 | egrep -q "[A-Za-z0-9_]+"; then
        if ! ip route | grep default | grep -q wlan0; then
            if file_is_recent /tmp/bad_wifi 60 && grep -q "$(iwgetid -r wlan0)" /tmp/bad_wifi; then
                echo Not renewing wlan0 IP due to recent connectivity failure:
                ls -la /tmp/bad_wifi
            else
                echo Attempting to renew wlan0 IP
                sudo dhclient wlan0
            fi
        fi
    fi
    if ifconfig | egrep -q "wlan0" >/dev/null; then
    #if [[ $(ip -4 -o addr show dev wlan0 | awk '{split($4,a,"/");print a[1]}') = $(print_local_ip wlan0) ]]; then
        print_wifi_name
        echo -n "At $(date) my local wifi IP is: "
        print_local_ip wlan0
    fi
    if ifconfig | egrep -q "bnep0" >/dev/null; then
        #if [[ $(ip -4 -o addr show dev bnep0 | awk '{split($4,a,"/");print a[1]}') = $(print_local_ip bnep0) ]]; then
            print_bluetooth_name
        #fi
        echo -n "At $(date) my local Bluetooth IP is: "
        print_local_ip bnep0
    else
        echo "At $(date) my Bluetooth PAN is not connected"
    fi
    ping_default_gateways
    echo -n "At $(date) my public IP is: "
    if check_ip; then
        stop_hotspot
        if has_ip wlan0 && has_ip bnep0; then
            # if online via BT w/o a DHCP IP, cycle wifi
            if print_local_ip wlan0 | grep $HostAPDIP || ! has_ip wlan0; then
                ifdown wlan0; ifup wlan0
            fi
        fi
        if ! test -f preferences.json \
            || ! jq -e .bt_with_wifi < preferences.json > /dev/null; then
            # if online via wifi, disconnect BT
            if has_ip wlan0 && ifconfig | egrep -q "bnep0" >/dev/null; then
                bt_disconnect $MACs
                #wifi_dhcp_renew
            fi
        else
            if ifconfig | egrep -q "bnep0" >/dev/null; then
                echo "Preference bt_with_wifi is enabled - have bt iface; leaving enabled."
                if ! has_ip wlan0; then
                    echo "Preference bt_with_wifi is enabled - enabling wifi."
                    wifi_dhcp_renew
                fi
                ifconfig | egrep -A6 "wlan|bnep"
            else
                if ! find /tmp/ -mmin -10 -name bt_with_wifi.last | grep bt_with_wifi.last 2>/dev/null >/dev/null; then
                    echo "Preference bt_with_wifi is enabled - have wifi connection, starting bt."
                    bt_connect $MACs
                    touch /tmp/bt_with_wifi.last
                fi
            fi
        fi
    else
        echo
        print_wifi_name
        if ! has_ip wlan0; then
            wifi_dhcp_renew
        fi
        if ! test -f preferences.json \
            || ! jq -e .bt_with_wifi < preferences.json > /dev/null; then
            if ! check_ip >/dev/null; then
                bt_connect $MACs
            fi
        else
            echo "Preference bt_with_wifi is enabled - starting bt regardless of wifi status."
            bt_connect $MACs
            ifconfig | egrep -A6 "wlan|bnep"
        fi
        #print_wifi_name
        if check_ip >/dev/null; then
            # if we're online after activating bluetooth, shut down any local-access hotspot we're running
            stop_hotspot
            if ! print_local_ip wlan0 | egrep -q "[A-Za-z0-9_]+" >/dev/null; then
                wifi_dhcp_renew
            fi
        else
            # if we can't connect via BT, might as well try previously bad wifi networks again
            rm /tmp/bad_wifi
            # if we can't get online via wifi or bluetooth, start our own local-access hotspot
            start_hotspot $@
            # don't disconnect bluetooth when starting local-only hotspot
        fi
    fi
    echo Finished oref0-online at $(date).
}

function print_bluetooth_name {
    echo -n "At $(date) my Bluetooth is connected to "
    grep Name /var/lib/bluetooth/*/*/info | awk -F = '{print $2}'
    #echo ${MACs}
}

function print_wifi_name {
    SSID=$(iwgetid -r wlan0 | nonl)
    if [[ ! -z $SSID ]]; then
        echo "At $(date) my wifi network name is $SSID"
    else
        echo "At $(date) my wifi is not connected"
    fi
}

function print_local_ip {
    LOCAL_IP=$(ip -4 -o addr show dev $1 | awk '{split($4,a,"/");print a[1]}')
    if [[ -z $LOCAL_IP ]]; then
        echo unassigned
    else
        echo $LOCAL_IP
    fi
}

function check_ip {
    PUBLIC_IP=$(curl --compressed -4 -s -m 15 checkip.amazonaws.com | awk -F '[, ]' '{print $NF}' | egrep "^[12]*[0-9]*[0-9]\.[12]*[0-9]*[0-9]\.[12]*[0-9]*[0-9]\.[12]*[0-9]*[0-9]$")
    if [[ -z $PUBLIC_IP ]]; then
        echo not found
        rm /tmp/publicIP 2> /dev/null
        return 1
    else
        echo $PUBLIC_IP
        echo $PUBLIC_IP > /tmp/publicIP
    fi
}

# network_name ip metric
function ping_to_default_gw {
ping $2 -c 1 > /dev/null
    if [[ $? == 0 ]] ; then
        echo At $(date) ping to default gateway $2 '('$1' metric = '$3')' passed ;
    else
        echo At $(date) ping to default gateway $2 '('$1' metric = '$3')' failed ;
    fi
}

function ping_default_gateways {
# Here is an example to the output of the netstat command that we parse.
# route -n
# Kernel IP routing table
# Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
# 0.0.0.0         192.168.44.1    0.0.0.0         UG    0      0        0 bnep0
# 0.0.0.0         192.168.44.1    0.0.0.0         UG    214    0        0 bnep0
# 0.0.0.0         192.168.3.1     0.0.0.0         UG    302    0        0 wlan0
# 192.168.3.0     0.0.0.0         255.255.255.0   U     302    0        0 wlan0
# 192.168.44.0    0.0.0.0         255.255.255.0   U     214    0        0 bnep0
route -n | grep ^0.0.0.0 |awk '{print $8 " " $2 " " $5}'| uniq | while read -r line ; do
    ping_to_default_gw $line
done
}

function has_ip {
    ifconfig | grep -A1 $1 | grep -q "inet "
}

function bt_connect {
    # loop over as many MACs as are provided as arguments
    for MAC; do
        #echo -n "At $(date) my public IP is: "
        if ! check_ip >/dev/null \
               || (test -f preferences.json \
                && jq -e .bt_with_wifi < preferences.json > /dev/null); then
            echo; echo "No Internet access detected, attempting to connect BT to $MAC"
            if ! is_bash_process_running_named "oref0-bluetoothup"; then
                oref0-bluetoothup
            else
                echo "oref0-bluetoothup already running"
            fi

            if ! test -f preferences.json \
                || ! jq -e .bt_offline < preferences.json > /dev/null \
                || ! ifconfig | egrep -q "bnep0" >/dev/null; then
                echo "Attempting to connect to bt $MAC..."
                sudo bt-pan -i $hci_address client $MAC -d
              for i in {1..3}
              do
                sudo bt-pan -i $hci_address client $MAC
                sudo dhclient bnep0
              done
                if ! has_ip bnep0; then
                  bt_bnep0_cycle
                fi
            else
                echo "Preference bt_offline enabled - already have a bt interface, not reconnecting it."
                sudo dhclient bnep0
                ifconfig | egrep -A6 "wlan|bnep"
                if ! has_ip bnep0; then
                  bt_bnep0_cycle
                fi
            fi
            if ifconfig | egrep -q "bnep0" >/dev/null; then
                echo -n "Connected to Bluetooth with IP: "
                print_local_ip bnep0
            fi
            # if we couldn't reach the Internet over wifi, but (now) have a bnep0 IP, release the wifi IP/route
            if has_ip wlan0 && has_ip bnep0 && ! grep -q $HostAPDIP /etc/network/interfaces; then
                   if ! test -f preferences.json \
                   || ! jq -e .bt_with_wifi < preferences.json > /dev/null; then
                    echo "Have bt connection, releasing wifi"
                    # release the wifi IP/route but *don't* renew it, in case it's not working
                    sudo dhclient wlan0 -r
                    iwgetid -r wlan0 >> /tmp/bad_wifi
                fi
            fi
            #echo
        fi
    done
}

function bt_disconnect {
    echo "Disconnecting BT $MAC"
    ifdown bnep0
    # loop over as many MACs as are provided as arguments
    for MAC; do
        sudo bt-pan -i $hci_address client $MAC -d
    done
}

function wifi_dhcp_renew {
    if file_is_recent /tmp/bad_wifi 60 && grep -q "$(iwgetid -r wlan0)" /tmp/bad_wifi; then
        echo Not renewing wlan0 IP due to recent connectivity failure:
        ls -la /tmp/bad_wifi
    else
        echo; echo "Getting new wlan0 IP"
        ps aux | grep -v grep | grep -q "dhclient wlan0" && sudo killall dhclient
        sudo dhclient wlan0 -r
        sudo dhclient wlan0
    fi
}

function stop_hotspot {
    if grep -q $HostAPDIP /etc/network/interfaces || iwconfig wlan0 | grep Mode:Master; then
        echo "Shutting down local-only hotspot"
        echo "Attempting to stop hostapd"
        /etc/init.d/hostapd stop
        echo "Attempting to stop dnsmasq"
        /etc/init.d/dnsmasq stop
        echo "Activating client config"
        ifdown wlan0
        cp /etc/network/interfaces.client /etc/network/interfaces
        ifup wlan0
        echo "Renewing IP Address for wlan0"
        dhclient_restart
    else
        echo -n "At $(date) my local hotspot is not running"
        if ! check_pref_bool .offline_hotspot false; then
            echo " (and not enabled in preferences.json)"
        else
            echo
        fi
    fi
}

function stop_cycle {
    stop_hotspot
    echo "Cycling wlan0"
    ifdown wlan0; ifup wlan0
}

function bt_bnep0_cycle {
  echo -n "No IP address assigned, cycling the bnep0 interface"
  sudo ifdown bnep0; sudo ifup bnep0;
  echo "...done"
}


function start_hotspot {
    echo
    if ls /tmp/disable_hotspot; then
        stop_cycle
    elif ! check_pref_bool .offline_hotspot false; then
        echo "Offline hotspot not enabled in preferences.json"
        stop_cycle
    elif [[ -z $1 ]]; then
        echo "No BT MAC provided: not activating local-only hotspot"
        echo "Cycling wlan0"
        ifdown wlan0; ifup wlan0
    elif grep -q $HostAPDIP /etc/network/interfaces \
        && ifconfig wlan0 | grep -q $HostAPDIP; then
        echo "Local hotspot is running."
        service hostapd status > /dev/null || service hostapd restart
        service dnsmasq status > /dev/null || service dnsmasq restart
    elif ! ls /etc/network/interfaces.ap 2>/dev/null >/dev/null; then
        echo "Local-only hotspot not configured"
        stop_cycle
    else
        echo "Unable to connect via wifi or Bluetooth; activating local-only hotspot"
        echo "Killing wpa_supplicant"
        #killall wpa_supplicant
        wpa_cli terminate
        echo "Shutting down wlan0"
        ifdown wlan0
        echo "Activating AP config"
        cp /etc/network/interfaces.ap /etc/network/interfaces
        ifup wlan0
        echo "Attempting to start hostapd"
        /etc/init.d/hostapd start
        echo "Attempting to start dnsmasq"
        service udhcpd stop
        /etc/init.d/dnsmasq start
        systemctl daemon-reload
        #echo "Stopping networking"
        #/etc/init.d/networking stop
        #echo "Starting networking"
        #/etc/init.d/networking start
        sleep 5
        echo "Setting IP Address for wlan0"
        /sbin/ifconfig wlan0 $HostAPDIP netmask 255.255.255.0 up
    fi
}

function dhclient_restart {
    ps aux | grep -v grep | grep -q "dhclient wlan0" && sudo killall dhclient
    sudo dhclient wlan0 -r
    sudo dhclient wlan0
}

function restart_networking {
    echo; echo "Error, cycling networking "
    sudo /etc/init.d/networking stop
    sleep 5
    sudo /etc/init.d/networking start
    echo "and getting new wlan0 IP"
    dhclient_restart
}

main "$@"