#!/bin/bash
# Script to set fixed MAC address and disable Wi-Fi if eth0 configuration succeeds
# Must be run with sudo!
# Update: Agora gera um MAC único automaticamente se nenhum for especificado (resolver problema do DM9601).

# --- Configuration ---
ETH0_MAC="00:00:00:00:00:00"  # Default MAC - será alterado automaticamente se mantiver este valor
# WLAN0_MAC="XX:XX:XX:XX:XX:XX"  # Uncomment and set if needed

# Verify root privileges
if [ "$(id -u)" -ne 0 ]; then
    echo "This script must be run as root" >&2
    exit 1
fi

# --- Functions ---
# Function to set MAC and verify success
set_mac() {
    local interface="$1"
    local mac="$2"
    local success=false
    local log_file="/var/log/set_mac.log"

    # Verifica se a interface existe
    if ! ip link show "$interface" &> /dev/null; then
        echo "$(date): Interface $interface não encontrada." | tee -a "$log_file"
        return 1
    fi

    # Verifica se macchanger está instalado
    if command -v macchanger >/dev/null 2>&1; then
        echo "$(date): Usando macchanger para definir MAC de $interface para $mac" | tee -a "$log_file"
        # Tenta usar macchanger
        if ip link set "$interface" down && \
           macchanger -m "$mac" "$interface" >/dev/null 2>&1 && \
           ip link set "$interface" up; then
            echo "$(date): Sucesso ao definir MAC com macchanger para $interface (novo: $mac)" | tee -a "$log_file"
            success=true
        else
            echo "$(date): Falha ao definir MAC com macchanger para $interface. Tentando fallback com ip link..." | tee -a "$log_file"
        fi
    fi

    # Fallback para ip link (se macchanger não estiver disponível ou falhar)
    if [ "$success" = false ]; then
        # Tenta com ip link diretamente
        if ip link set "$interface" down && \
           ip link set dev "$interface" address "$mac" && \
           ip link set "$interface" up; then
            echo "$(date): Sucesso ao definir MAC com 'ip link' para $interface (novo: $mac)" | tee -a "$log_file"
            success=true
        else
            echo "$(date): Falha ao definir MAC para $interface com ambos os métodos." | tee -a "$log_file"
            return 1
        fi
    fi

    # Retorna sucesso (0) ou falha (1)
    return $([ "$success" = true ] && echo 0 || echo 1)
}

# Function to configure static IP
configure_static_ip() {
    local ip_script="/usr/local/bin/set_static_ip.sh"

    if [ -f "$ip_script" ]; then
        # Get current IP configuration
        local interface
        if interface=$(get_active_interface); then
            local current_ip=$(ip -4 addr show "$interface" | grep -oP '(?<=inet\s)\d+(\.\d+){3}')
            if [[ "$current_ip" =~ ^169\.254\. ]]; then
                # Link-local address, likely no DHCP
                log "No valid IP address found for $interface, configuring static IP..."
                IP_ADDRESS_ENV="10.10.0.100/24" bash "$ip_script"
            fi
        fi
    fi
}

# Function to check if interface has IP address
has_ip_address() {
    local interface="$1"
    # Check if interface is UP and has an IPv4 address
    if ip link show "$interface" | grep -q "state UP" && \
       ip -4 addr show "$interface" | grep -q "inet "; then
        return 0
    else
        return 1
    fi
}

# Function to disable Wi-Fi
disable_wifi() {
    # Create log directory if it doesn't exist
    mkdir -p /var/log

    # Wait for 1 minute (60 seconds) before disabling Wi-Fi
    echo "$(date): Waiting 60 seconds before checking eth0 IP and disabling Wi-Fi..." | tee -a /var/log/set_mac.log
    sleep 60

    # Check if eth0 has an IP address before disabling Wi-Fi
    if has_ip_address "eth0"; then
        if ip link show "wlan0" &> /dev/null; then
            if ip link set "wlan0" down; then
                echo "$(date): Wi-Fi (wlan0) disabled successfully (eth0 has IP)" | tee -a /var/log/set_mac.log
            else
                echo "$(date): Failed to disable Wi-Fi (wlan0)" | tee -a /var/log/set_mac.log
            fi
        else
            echo "$(date): wlan0 interface not found (Wi-Fi already disabled?)" | tee -a /var/log/set_mac.log
        fi
    else
        echo "$(date): eth0 does not have an IP address. Wi-Fi remains active." | tee -a /var/log/set_mac.log
    fi
}

# --- Novas Funções Complementares (Dinâmicas) ---

# Função para gerar um MAC único baseado no Serial do Raspberry Pi
# Garante que cada dispositivo fica com um MAC diferente mas consistente
generate_unique_mac() {
    local serial
    serial=$(awk '/Serial/ {print $3}' /proc/cpuinfo | tr -d ' ')
    
    if [ -z "$serial" ]; then
        # Fallback aleatório caso não encontre serial
        printf '%02X:%02X:%02X:%02X:%02X:%02X' $((0x02 | (RANDOM % 256) & 0xFE)) $((RANDOM % 256)) $((RANDOM % 256)) $((RANDOM % 256)) $((RANDOM % 256)) $((RANDOM % 256))
    else
        # Gera hash do serial para criar os octetos
        local hash
        hash=$(echo -n "$serial-dm9601" | md5sum | cut -c1-10)
        # 02 define como Local Admin Address
        echo "02:${hash:0:2}:${hash:2:2}:${hash:4:2}:${hash:6:2}:${hash:8:2}"
    fi
}

# Função para criar regra Udev persistente (Best Practice)
# Isto faz com que o MAC seja aplicado no boot, evitando erros de "Device Busy"
setup_udev_persistence() {
    local interface="$1"
    local target_mac="$2"
    local log_file="/var/log/set_mac.log"

    # Obtém o MAC original (físico) do adaptador
    local original_mac
    original_mac=$(ip link show "$interface" | awk '/ether/ {print $2}' | tr '[:upper:]' '[:lower:]')
    target_mac=$(echo "$target_mac" | tr '[:upper:]' '[:lower:]')

    if [ -z "$original_mac" ]; then return 1; fi

    local rules_file="/etc/udev/rules.d/81-mac-spoof.rules"

    # Se a regra já existe para este MAC original, não faz nada
    if grep -q "$original_mac" "$rules_file" 2>/dev/null; then
        return 0
    fi

    echo "$(date): Criando regra udev persistente para $interface" | tee -a "$log_file"
    echo "ACTION==\"add\", SUBSYSTEM==\"net\", ATTR{address}==\"$original_mac\", RUN+=\"/usr/bin/ip link set dev \$name address $target_mac\"" >> "$rules_file"
    udevadm control --reload-rules
}

# --- Execução Principal ---

# LÓGICA COMPLEMENTAR:
# Se ETH0_MAC for o valor padrão (00:00...) ou vazio, gera um novo automaticamente.
if [ -z "$ETH0_MAC" ] || [ "$ETH0_MAC" == "00:00:00:00:00:00" ]; then
    echo "$(date): Nenhum MAC específico definido. Gerando MAC único automático..." | tee -a /var/log/set_mac.log
    ETH0_MAC=$(generate_unique_mac)
    echo "$(date): Novo MAC gerado: $ETH0_MAC" | tee -a /var/log/set_mac.log
fi

# Executa a lógica original com o MAC definido (seja o do config ou o gerado)
if set_mac "eth0" "$ETH0_MAC"; then
    # Se definiu o MAC com sucesso, tenta criar persistência via Udev
    # Isto resolve o problema do adapter mantendo o MAC em futuros boots
    setup_udev_persistence "eth0" "$ETH0_MAC"

    # Check if disable_wifi is already running
    if ! pgrep -f "disable_wifi" > /dev/null; then
        #configure_static_ip
        disable_wifi &
    else
        echo "$(date): disable_wifi is already running" | tee -a /var/log/set_mac.log
    fi
else
    echo "$(date): Could not set MAC for eth0. Wi-Fi remains active" | tee -a /var/log/set_mac.log
fi

# Uncomment if you want to set MAC for wlan0 (optional)
# if [[ -n "$WLAN0_MAC" ]]; then
#     set_mac "wlan0" "$WLAN0_MAC"
# fi