I am trying to develop an access point that can be used to 'headlessly' connect to wifi.

AP

I am setting up the access point using hostapd conf:

interface=wlan0
ssid=AP
hw_mode=g
channel=6
auth_algs=1
wmm_enabled=0

adding to my /etc/hosts

192.168.1.1 nginx.ap.com

and to my dnsmasq:

# Never forward addresses in the non-routed address spaces.
bogus-priv
#　Add other name servers here, with domain specs if they are for　non-public domains.
server=/localnet/192.168.1.1
# Add local-only domains here, queries in these domains are answered　from /etc/hosts or DHCP only.
local=/localnet/
# Make all host names resolve to the Raspberry Pi's IP address
address=/#/192.168.1.1
# Specify the interface that will listen for DHCP and DNS requests
interface=wlan0
# Set the domain for dnsmasq
domain=localnet
# Specify the range of IP addresses the DHCP server will lease out to devices, and the duration of the lease
dhcp-range=192.168.1.10,192.168.1.254,1h
# Specify the default route
dhcp-option=3,192.168.1.1
# Specify the DNS server address
dhcp-option=6,192.168.1.1
# Set the DHCP server to authoritative mode.
dhcp-authoritative

log-dhcp
log-queries
log-facility=/tmp/dnsmasq.log

and a LAMP server that listens for nginx.ap.com this is not really working how I imagined as I had to customise the DNS on my mac so that it would use the pis and I only get access if I type http://nginx.ap.com into the browser I was hoping I would get a pop up and all other domains would redirect to this.

networking

For my /etc/network/interfaces:

iface wlan0 inet static
 address 192.168.1.1
 netmask 255.255.255.0

I am now trying to come up with a script that the nginx web server can run using php to close the access point and connect to the wifi using a SSID and password from a HTML form.

I have the check to see if the SSID exists in the network which works with this bash script:

if ! iwlist scan | grep ""$name"" &> /dev/null
then
 echo "No such SSID - '$name'";
 exit
fi

I now want to check if the password is correct and then to never use the access point again if there is a valid wifi.

So I run a simple cron like this:

if ! ping -c 2 8.8.8.8 &> /dev/null
then
 service hostapd start
 service dnsmasq start
else
 service hostapd stop
 service dnsmasq stop
fi

but this does not work properly as I will also need to control the /etc/network/interfaces and refresh the network and to do that I have to boot the user off the AP thus destroying any possible feedback.

Is there a way to check whether a config works without disconnecting the access point? And any other tips would be greatly appreciated.