#! /bin/bash

. /usr/lib/network/network
. "$SUBR_DIR/8021x"
. /etc/conf.d/netcfg

usage()
{
    cat << END
Usage: wifi-menu [-o | --obscure] [-h | --help] [interface]

Interactively connect to a wireless network.

Arguments:
  -o, --obscure  Show asterisks for the characters of the password
                 and store the password as a hexadecimal string.
  -h, --help     Show this help.
  interface      The wireless interface to use.
                 (default: WIRELESS_INTERFACE from /etc/conf.d/netcfg)

For choosing from all available profiles, use netcfg-menu.
END
}

# Fills PROFILES and ESSIDS with the profile names and essids of the profiles
# for interface $1.
init_profiles()
{
    local i=0 essid profile
    while read profile; do
        essid=$(
            unset INTERFACE ESSID
            . "$PROFILE_DIR/$profile" &> /dev/null
            if [[ "$INTERFACE" = "$1" && -n "$ESSID" ]]; then
                printf "%s" "$ESSID"
                if [[ "$DESCRIPTION" =~ "Automatically generated" ]]; then
                    return 2
                else
                    return 1
                fi
            fi
            return 0
        )
        case $? in
            2)
                GENERATED+=("$profile")
                ;&
            1)
                PROFILES[i]=$profile
                ESSIDS[i]=$essid
                (( ++i ))
                ;;
        esac
    done < <(list_profiles)
}

# Builds ENTRIES as an argument list for dialog based on scan results in $1.
init_entries()
{
    local i=0 flags signal ssid
    while IFS=$'\t' read signal flags ssid; do
        ENTRIES[i++]="--"  # $ssid might look like an option to dialog.
        ENTRIES[i++]=$ssid
        if inarray "$ssid" "${ESSIDS[@]}"; then
            if inarray "$(ssid_to_profile "$ssid")" "${GENERATED[@]}"; then
                ENTRIES[i]="+"  # Automatically generated
            else
                ENTRIES[i]="*"  # Handmade
            fi
        else
            ENTRIES[i]="-"  # Not present
        fi
        if [[ "$ssid" = "$CONNECTION" ]]; then
            ENTRIES[i]="!"  # Currently connected
        fi
        if [[ "$flags" =~ WPA2|WPA|WEP ]]; then
            ENTRIES[i]+=":${BASH_REMATCH[0],,}"
        else
            ENTRIES[i]+=":none"
        fi
        ENTRIES[i]+="   :$signal"
        (( ++i ))
    done < "$1"
}

# Finds a profile name for ssid $1.
ssid_to_profile()
{
    local i
    for i in $(seq 0 $((${#ESSIDS[@]}-1))); do
        if [[ "$1" = "${ESSIDS[i]}" ]]; then
            printf "%s" "${PROFILES[i]}"
            return 0
        fi
    done
    return 1
}

# Creates a profile for ssid $1.
create_profile()
{
    local box flags key msg security
    PROFILE="$INTERFACE-${1//\//_}"
    [[ -e "$PROFILE_DIR/$PROFILE" ]] && PROFILE+=".wifi-menu"
    flags=$(grep -F -m 1 $'\t'"$1\$" "$NETWORKS" | cut -f 2)
    if [[ "$flags" =~ WPA|WEP ]]; then
        security=${BASH_REMATCH[0],,}
    else
        security=none
    fi
    if [[ "$flags" =~ PSK|WEP ]]; then
        [[ "$OBSCURE" ]] && box="--insecure --passwordbox" || box="--inputbox"
        msg="Enter $security security key for\n'$1'"
        key=$(dialog $box "$msg" 10 40 --stdout) || return $?
        [[ "${#key}" -ge 8 && "${#key}" -le 63 ]] || return 4
        if [[ "$OBSCURE" ]]; then
            key=$(wpa_passphrase "$1" "$key" | grep -m 1 "^[[:space:]]*psk=")
            key="KEY=${key#*psk=}"
        else
            key="KEY=$(printf "%q" "$key")"
        fi
    fi
    cat << EOF > "$PROFILE_DIR/$PROFILE"
CONNECTION='wireless'
DESCRIPTION='Automatically generated profile by wifi-menu'
INTERFACE='$INTERFACE'
SECURITY='$security'
ESSID=$(printf "%q" "$1")
IP='dhcp'
$key
EOF
    printf "%s" "$PROFILE"
    return 0
}

# Connects to ssid $1 using an available profile or an automatically created
# one if none exists.
connect_to_ssid()
{
    local msg
    PROFILE=$(ssid_to_profile "$1")
    if [[ $? -eq 0 ]]; then
        clear
        check_profile "$PROFILE" && profile_down "$PROFILE"
    else
        PROFILE=$(create_profile "$1")
        RETURN=$?
        (( RETURN == 0 )) || return $RETURN
        SPAWNED_PROFILE=1
        clear
    fi
    if ! profile_up "$PROFILE"; then
        if (( SPAWNED_PROFILE )); then
            msg="         CONNECTING FAILED

Do you want to keep the generated profile ('$PROFILE')?"
            dialog --yesno "$msg" 10 40 --stdout || rm "$PROFILE_DIR/$PROFILE"
            clear
        fi
        return 2
    fi
    return 0
}

while [[ "$1" = -* ]]; do
    case "$1" in
        -h|--help)
            usage
            exit
            ;;
        -o|--obscure)
            OBSCURE=1
            shift
            ;;
        -*)
            report_err "Invalid option: $1"
            usage
            exit 255
            ;;
    esac
done
if [[ $# -gt 1 ]]; then
    report_err "Too many arguments"
    usage
    exit 255
fi

if [[ $(id -u) -ne 0 ]]; then
    exit_stderr "This script needs to be run with root privileges"
fi
if ! type dialog &> /dev/null; then
    exit_stderr "Please install 'dialog' to use wifi-menu"
fi

INTERFACE=${1-$WIRELESS_INTERFACE}
if [[ -z "$INTERFACE" ]]; then
    report_err "Missing interface specification"
    usage
    exit 255
fi

cd /  # We do not want to spawn anything that can block unmounting
is_interface "$INTERFACE" || exit_fail "No such interface: $INTERFACE"
if ! interface_is_up "$INTERFACE"; then
    [[ -f "$IFACE_DIR/$INTERFACE" ]] && . "$IFACE_DIR/$INTERFACE"
    bring_interface up "$INTERFACE" || exit_fail "Interface unavailable"
    SPAWNED_INTERFACE=1
fi

report_try "Scanning for networks"
CONNECTION=$(wpa_call "$INTERFACE" status 2> /dev/null | grep -m 1 "^ssid=")
CONNECTION=${CONNECTION#ssid=}
NETWORKS=$(wpa_supplicant_scan_info "$INTERFACE" 3,4,5)
if [[ $? -eq 0 ]]; then
    trap 'rm -f "$NETWORKS"' EXIT
    report_success
    init_profiles "$INTERFACE"
    init_entries "$NETWORKS"
    MSG="Select the network you wish to use
Flags description:
 * - handmade profile present
 + - automatically generated profile present
 - - no profile present
 ! - active connection present"
    CHOICE=$(dialog --column-separator : --menu "$MSG" 24 50 12 \
                 "${ENTRIES[@]}" --stdout)
    RETURN=$?
    if (( RETURN == 0 )); then
        connect_to_ssid "$CHOICE"
        RETURN=$?
    fi
else
    report_fail
    RETURN=3
fi

case $RETURN in
    0|2)  # Connected | Connecting failed
        ;;
    1)  # Canceled
        clear
        ;;
    3)  # No networks found
        report_err "No networks found"
        ;;
    4)  # Invalid passphrase length (WEP keys have tighter restrictions)
        clear
        report_err "Passphrase must be 8..63 characters"
        ;;
    255)  # ESC or error
        clear
        report_err "Aborted"
        ;;
    *)  # Should not happen
        report_err "Unexpected return code from dialog: $RETURN"
        RETURN=7
        ;;
esac
(( RETURN && SPAWNED_INTERFACE )) && bring_interface down "$INTERFACE"
exit $RETURN