#!/bin/bash

# Find a free port and return it
#
# usage: ynh_find_port --port=begin_port
# | arg: -p, --port=    - port to start to search
# | ret: the port number
#
# example: port=$(ynh_find_port --port=8080)
#
# Requires YunoHost version 2.6.4 or higher.
ynh_find_port () {
    # Declare an array to define the options of this helper.
    local legacy_args=p
    local -A args_array=( [p]=port= )
    local port
    # Manage arguments with getopts
    ynh_handle_getopts_args "$@"

    test -n "$port" || ynh_die --message="The argument of ynh_find_port must be a valid port."
    while ! ynh_port_available --port=$port
    do
        port=$((port+1))	# Else, pass to next port
    done
    echo $port
}

# Test if a port is available
#
# usage: ynh_find_port --port=XYZ
# | arg: -p, --port=    - port to check
# | ret: 0 if the port is available, 1 if it is already used by another process.
#
# example: ynh_port_available --port=1234 || ynh_die --message="Port 1234 is needs to be available for this app"
#
# Requires YunoHost version 3.8.0 or higher.
ynh_port_available () {
    # Declare an array to define the options of this helper.
    local legacy_args=p
    local -A args_array=( [p]=port= )
    local port
    # Manage arguments with getopts
    ynh_handle_getopts_args "$@"

    if ss --numeric --listening --tcp --udp | awk '{print$5}' | grep --quiet --extended-regexp ":$port$"       # Check if the port is free
    then
        return 1
    else
        return 0
    fi
}


# Validate an IP address
#
# [internal]
#
# usage: ynh_validate_ip --family=family --ip_address=ip_address
# | ret: 0 for valid ip addresses, 1 otherwise
#
# example: ynh_validate_ip 4 111.222.333.444
#
# Requires YunoHost version 2.2.4 or higher.
ynh_validate_ip()
{
    # http://stackoverflow.com/questions/319279/how-to-validate-ip-address-in-python#319298

    # Declare an array to define the options of this helper.
    local legacy_args=fi
    local -A args_array=( [f]=family= [i]=ip_address= )
    local family
    local ip_address
    # Manage arguments with getopts
    ynh_handle_getopts_args "$@"

    [ "$family" == "4" ] || [ "$family" == "6" ] || return 1

  python /dev/stdin << EOF
import socket
import sys
family = { "4" : socket.AF_INET, "6" : socket.AF_INET6 }
try:
    socket.inet_pton(family["$family"], "$ip_address")
except socket.error:
    sys.exit(1)
sys.exit(0)
EOF
}

# Validate an IPv4 address
#
# usage: ynh_validate_ip4 --ip_address=ip_address
# | arg: -i, --ip_address=     - the ipv4 address to check
# | ret: 0 for valid ipv4 addresses, 1 otherwise
#
# example: ynh_validate_ip4 111.222.333.444
#
# Requires YunoHost version 2.2.4 or higher.
ynh_validate_ip4()
{
    # Declare an array to define the options of this helper.
    local legacy_args=i
    local -A args_array=( [i]=ip_address= )
    local ip_address
    # Manage arguments with getopts
    ynh_handle_getopts_args "$@"

    ynh_validate_ip --family=4 --ip_address=$ip_address
}


# Validate an IPv6 address
#
# usage: ynh_validate_ip6 --ip_address=ip_address
# | arg: -i, --ip_address=  - the ipv6 address to check
# | ret: 0 for valid ipv6 addresses, 1 otherwise
#
# example: ynh_validate_ip6 2000:dead:beef::1
#
# Requires YunoHost version 2.2.4 or higher.
ynh_validate_ip6()
{
    # Declare an array to define the options of this helper.
    local legacy_args=i
    local -A args_array=( [i]=ip_address= )
    local ip_address
    # Manage arguments with getopts
    ynh_handle_getopts_args "$@"

    ynh_validate_ip --family=6 --ip_address=$ip_address
}