#!/usr/bin/bash

frontend_port=3000
server_port=8080
ssh_port=34355

frontend_node_ids=(2)
server_node_ids=(4 5 6)

build_dir="${HOME}/build"

#server_name="usufslc-pi-cluster.bluezone.usu.edu"
server_name="chessh.linux.usu.edu"
load_balancer_nginx_site_file="/etc/nginx/sites-enabled/${server_name}.conf"
ha_proxy_cfg="/etc/haproxy/haproxy.cfg"
ssl_cert_path="/etc/letsencrypt/live/${server_name}"
certbot_webroot_path="/var/www/html/${server_name}"
load_balancer_nginx_site="
upstream frontend {
	$(printf "server 192.168.100.%s:${frontend_port};\n" ${frontend_node_ids[@]})
}

upstream api {
	$(printf "server 192.168.100.%s:${server_port};\n" ${server_node_ids[@]})
}

server {
	default_type  application/octet-stream;

	server_name ${server_name};

	listen 443 ssl;
	ssl_certificate ${ssl_cert_path}/fullchain.pem;
	ssl_certificate_key ${ssl_cert_path}/privkey.pem;
	include /etc/letsencrypt/options-ssl-nginx.conf;
	ssl_dhparam /etc/letsencrypt/ssl-dhparams.pem;

	location ~ /.well-known {
		allow all;
		default_type "text/plain";
		alias ${certbot_webroot_path};
	}	

	location /api/ {
		proxy_set_header Host \$host;
		proxy_set_header X-Real-IP \$remote_addr;
		proxy_pass http://api/;
	}

	location / {
		proxy_set_header Host \$host;
		proxy_set_header X-Real-IP \$remote_addr;
		proxy_pass http://frontend/;
	}
}

server {
	if (\$host = ${server_name}) {
		return 301 https://\$host\$request_uri;
	}

	server_name ${server_name};
	listen 80;
	return 404;
}
"
# TODO: Servers should pull server ids from array
ha_proxy_cfg="
global\n
	log /dev/log 	local0\n
	log /dev/log	local1 notice\n
	maxconn 2500\n
	user haproxy\n
	group haproxy\n
	daemon\n
\n
defaults\n
	log 	global\n
	mode	tcp\n
	timeout connect 10s\n
	timeout client 36h\n
	timeout server 36h\n
	option 	dontlognull\n
\n
listen ssh\n
	bind 	*:${ssh_port}\n
	balance	leastconn\n
	mode	tcp\n

	server hostA  192.168.100.4:${ssh_port} check inter 10s fall 2 rise 1\n
	server hostB  192.168.100.5:${ssh_port} check inter 10s fall 2 rise 1\n
	server hostC  192.168.100.6:${ssh_port} check inter 10s fall 2 rise 1\n
"
echo $ha_proxy_cfg

ssh_opts="-oStrictHostKeyChecking=no"

function make_pi_node_conn_str() {
    echo "pi$(printf "%04d" $1)@192.168.100.${1}"
}

function copy_ssh_keys() {
    if [ ! -d  "${build_dir}/keys" ]
    then
        mkdir "${build_dir}/keys"
        chmod 700 "${build_dir}/keys"
        cd "${build_dir}/keys"

        ssh-keygen -N "" -b 256  -t ecdsa -f ssh_host_ecdsa_key
        ssh-keygen -N "" -b 1024 -t dsa -f ssh_host_dsa_key
        ssh-keygen -N "" -b 2048 -t rsa -f ssh_host_rsa_key
    fi
    for node_id in "${server_node_ids[@]}"
    do
        node_conn=$(make_pi_node_conn_str $node_id)
        scp -r $ssh_opts "${build_dir}/keys" $node_conn:~
    done
}


function reload_nginx_confs() {
    dead_files=("/etc/nginx/sites-enabled/default" "/etc/nginx/nginx.conf" "$load_balancer_nginx_site_file")
    for file in "${dead_files[@]}"
    do
        [ -e $file ] && sudo rm $file
    done
    
    sudo cp "${build_dir}/nginx.conf" /etc/nginx/nginx.conf
    echo $load_balancer_nginx_site | sudo tee $load_balancer_nginx_site_file
    
    sudo systemctl restart nginx
}

function build_frontend() {
    node_id=$1
    node_conn=$(make_pi_node_conn_str $node_id)
    
    scp $ssh_opts "${build_dir}/.env" $node_conn:~
    scp $ssh_opts "${build_dir}/build_front.sh" $node_conn:~/
    ssh $ssh_opts $node_conn "~/build_front.sh"    
}

function build_frontend_nodes() {
    for node_id in "${frontend_node_ids[@]}"
    do
        build_frontend $node_id
    done
}

function build_server() {
    node_id=$1
	  node_conn=$(make_pi_node_conn_str $node_id)
    temp_file=$(mktemp)
    
    cp "${build_dir}/.env" $temp_file
    printf "\nNODE_ID=$node_id\n" >> $temp_file
    scp $ssh_opts $temp_file $node_conn:~/.env

    cp "${build_dir}/chessh.service" $temp_file
    sed -i "s/\$BUILD_ENV/\/home\/pi$(printf "%04d" $1)\/.env/" $temp_file
    scp -r $ssh_opts $temp_file $node_conn:~/chessh.service
    
    scp $ssh_opts "${build_dir}/build_server.sh" $node_conn:~/

    ssh $ssh_opts $node_conn "~/build_server.sh"
}

function build_server_nodes() {
    copy_ssh_keys
    
    for node_id in "${server_node_ids[@]}"
    do
        build_server $node_id
    done
}

reload_nginx_confs
build_server_nodes
build_frontend_nodes