#!/bin/bash

set -e

SCRIPT_URL="https://git.zakscode.com/ztimson/fallback-ap/raw/branch/master/fallback-ap.sh"
INSTALL_PATH="/usr/local/bin/fallback-ap"

if [ "$EUID" -ne 0 ]; then
    echo "This installer needs to run as root, e.g.:"
    echo "  curl -sL https://git.zakscode.com/ztimson/fallback-ap/raw/branch/master/install.sh | sudo bash"
    exit 1
fi

prompt() {
    local __var="$1" __question="$2" __default="$3" __answer=""
    read -r -p "$__question [$__default]: " __answer < /dev/tty || __answer=""
    printf -v "$__var" '%s' "${__answer:-$__default}"
}

EXISTING_CONFIG="/etc/fallback-ap.conf"

if [ -f "$EXISTING_CONFIG" ]; then
    # shellcheck disable=SC1090
    source "$EXISTING_CONFIG"
fi

DEFAULT_SSID="${SAVED_SSID:-$(hostname)}"
DEFAULT_PASSWORD="${SAVED_PASSWORD:-abcd1234}"
DEFAULT_CIDR="${SAVED_CIDR:-10.10.10.1/24}"
DEFAULT_DHCP_START_OCTET="${SAVED_DHCP_START_OCTET:-100}"
DEFAULT_DHCP_END_OCTET="${SAVED_DHCP_END_OCTET:-250}"

[ -z "${FALLBACK_AP_SSID:-}" ]              && prompt FALLBACK_AP_SSID "Access point SSID" "$DEFAULT_SSID"
[ -z "${FALLBACK_AP_PASSWORD:-}" ]          && prompt FALLBACK_AP_PASSWORD "Access point passphrase" "$DEFAULT_PASSWORD"
[ -z "${FALLBACK_AP_CIDR:-}" ]              && prompt FALLBACK_AP_CIDR "Access point subnet (CIDR)" "$DEFAULT_CIDR"
[ -z "${FALLBACK_AP_DHCP_START_OCTET:-}" ]  && prompt FALLBACK_AP_DHCP_START_OCTET "DHCP range start (last octet)" "$DEFAULT_DHCP_START_OCTET"
[ -z "${FALLBACK_AP_DHCP_END_OCTET:-}" ]    && prompt FALLBACK_AP_DHCP_END_OCTET "DHCP range end   (last octet)" "$DEFAULT_DHCP_END_OCTET"

export FALLBACK_AP_SSID FALLBACK_AP_PASSWORD FALLBACK_AP_CIDR FALLBACK_AP_DHCP_START_OCTET FALLBACK_AP_DHCP_END_OCTET

echo "Downloading fallback-ap..."
curl -fsSL "$SCRIPT_URL" -o "$INSTALL_PATH"
chmod +x "$INSTALL_PATH"
echo "Running installer..."
"$INSTALL_PATH" install