#!/usr/bin/env bash

# =============================================================================
# NetworkManager Captive Portal Auto-Detector
# =============================================================================
# Erstellt von Pascal Bouquet am 16.09.2025
# Aktualisiert am 18.09.2025
#
# Dieses Skript ist freie Software: Es kann frei verwendet, bearbeitet und 
# verbreitet werden. Es wird keine Garantie für die Funktionsfähigekeit übernommen.
# =============================================================================

# =============================================================================
# KONFIGURATION
# =============================================================================
LOG_FILE="/var/log/nm-captive.log"
LOG_LEVEL="ERROR"  # NONE, DEBUG, INFO, WARNING, ERROR
CHECK_INTERVAL=300  # 5 Minuten in Sekunden
MAX_CHECKS=12       # Maximal 1 Stunde lang prüfen (12 * 5min)

# Test-URLs für Captive Portal Erkennung
TEST_URLS=(
    "http://captive.apple.com/hotspot-detect.html"
    "http://connectivitycheck.gstatic.com/generate_204"
)

# =============================================================================
# FUNKTIONEN
# =============================================================================

log() {
    local level=$1
    local message=$2
    
    # Kein Logging wenn LOG_LEVEL=NONE
    if [ "$LOG_LEVEL" = "NONE" ]; then
        return
    fi
    
    # Log-Level Filterung
    case $LOG_LEVEL in
        "DEBUG") echo "$(date '+%Y-%m-%d %H:%M:%S') - $level - $message" >> "$LOG_FILE" ;;
        "INFO") 
            if [[ "$level" != "DEBUG" ]]; then
                echo "$(date '+%Y-%m-%d %H:%M:%S') - $level - $message" >> "$LOG_FILE"
            fi
            ;;
        "WARNING")
            if [[ "$level" == "WARNING" || "$level" == "ERROR" ]]; then
                echo "$(date '+%Y-%m-%d %H:%M:%S') - $level - $message" >> "$LOG_FILE"
            fi
            ;;
        "ERROR")
            if [[ "$level" == "ERROR" ]]; then
                echo "$(date '+%Y-%m-%d %H:%M:%S') - $level - $message" >> "$LOG_FILE"
            fi
            ;;
    esac
}

get_user_environment() {
    local user=$1
    local user_id=$(id -u "$user")
    
    # Finde den Desktop-Prozess und übernehme dessen Environment
    local pid=$(pgrep -u "$user" -n plasmashell || pgrep -u "$user" -n gnome-shell || pgrep -u "$user" -n kwin_wayland || echo "")
    
    if [ -n "$pid" ] && [ -f "/proc/$pid/environ" ]; then
        log "DEBUG" "Using environment from process $pid"
        # Extrahiere alle benötigten Environment-Variablen
        tr '\0' '\n' < "/proc/$pid/environ" | grep -E "(WAYLAND|DISPLAY|XDG|DBUS|USER|HOME|PATH)"
    else
        # Fallback: Basis-Environment setzen
        log "DEBUG" "Using fallback environment"
        echo "USER=$user"
        echo "HOME=/home/$user"
        echo "XDG_RUNTIME_DIR=/run/user/$user_id"
        echo "DBUS_SESSION_BUS_ADDRESS=unix:path=/run/user/$user_id/bus"
        
        # Versuche, den echten Display zu finden
        if [ -S "/run/user/$user_id/wayland-0" ]; then
            echo "WAYLAND_DISPLAY=wayland-0"
            echo "XDG_SESSION_TYPE=wayland"
        elif [ -S "/tmp/.X11-unix/X0" ]; then
            echo "DISPLAY=:0"
        else
            echo "DISPLAY=:0"
        fi
    fi
}

get_user_session() {
    local user=""
    local display=""
    local session_type=""
    
    # Finde den aktuellen GUI-Benutzer
    user=$(who | grep -E "(tty[0-9]|pts/)" | awk '{print $1}' | head -n1)
    log "DEBUG" "who found user: $user"
    
    if [ -n "$user" ]; then
        local user_id=$(id -u "$user")
        
        # Prüfe auf Wayland
        if [ -S "/run/user/$user_id/wayland-0" ]; then
            session_type="wayland"
            display="wayland-0"
            log "DEBUG" "Wayland socket detected"
        elif [ -S "/tmp/.X11-unix/X0" ]; then
            session_type="x11"
            display=":0"
            log "DEBUG" "X11 socket detected"
        else
            # Fallback basierend auf Prozessen
            if pgrep -u "$user" kwin_wayland >/dev/null; then
                session_type="wayland"
                display="wayland-0"
                log "DEBUG" "Wayland process detected"
            else
                session_type="x11"
                display=":0"
                log "DEBUG" "Assuming X11"
            fi
        fi
    fi
    
    echo "$user $display $session_type"
}

check_captive_portal() {
    local captive_detected=false
    
    for url in "${TEST_URLS[@]}"; do
        log "DEBUG" "Testing URL: $url"
        
        if [[ "$url" == *"apple.com"* ]]; then
            local response=$(curl -s -L --connect-timeout 5 "$url")
            if [ $? -ne 0 ]; then
                log "DEBUG" "Network error for $url"
                captive_detected=true
                break
            elif ! echo "$response" | grep -qi "success"; then
                log "DEBUG" "Apple check failed - no 'Success' in response"
                captive_detected=true
                break
            fi
            
        elif [[ "$url" == *"google"* || "$url" == *"gstatic"* ]]; then
            local http_code=$(curl -s -o /dev/null -w "%{http_code}" --connect-timeout 5 "$url")
            if [ $? -ne 0 ]; then
                log "DEBUG" "Network error for $url"
                captive_detected=true
                break
            elif [ "$http_code" != "204" ]; then
                log "DEBUG" "Google check failed - HTTP $http_code instead of 204"
                captive_detected=true
                break
            fi
        fi
    done
    
    if [ "$captive_detected" = true ]; then
        log "INFO" "Captive portal detected"
        return 1
    else
        log "INFO" "All connectivity checks passed - no captive portal"
        return 0
    fi
}

start_firefox() {
    local user=$1
    local display=$2
    local session_type=$3
    
    log "INFO" "Attempting to start Firefox for user: $user, display: $display, type: $session_type"
    
    # Holle die komplette Environment des Users
    local user_env=$(get_user_environment "$user")
    log "DEBUG" "User environment: $user_env"
    
    # Baue den sudo-Befehl mit der kompletten Environment
    local env_vars=""
    while IFS= read -r line; do
        if [ -n "$line" ]; then
            env_vars="$env_vars $line"
        fi
    done <<< "$user_env"
    
    # Starte Firefox mit der kompletten Environment
    log "DEBUG" "Starting Firefox with full user environment"
    sudo -u "$user" $env_vars firefox --new-window "http://detectportal.firefox.com/canonical.html" &
    
    local pid=$!
    sleep 1
    if ps -p $pid >/dev/null 2>&1; then
        log "INFO" "Firefox successfully started with PID: $pid"
        return 0
    else
        log "ERROR" "Firefox process died immediately after start"
        return 1
    fi
}

start_periodic_checks() {
    local interface="$1"
    local user="$2"
    local display="$3"
    local session_type="$4"
    local check_count=0
    
    log "INFO" "Starting periodic checks for $interface (every ${CHECK_INTERVAL}s)"
    
    while [ $check_count -lt $MAX_CHECKS ]; do
        sleep $CHECK_INTERVAL
        ((check_count++))
        
        log "DEBUG" "Periodic check $check_count/$MAX_CHECKS for $interface"
        
        if ! check_captive_portal; then
            log "INFO" "Captive portal still active - re-opening browser"
            
            if start_firefox "$user" "$display" "$session_type"; then
                log "INFO" "Firefox re-opened successfully"
            else
                log "ERROR" "Failed to re-open Firefox"
            fi
        else
            log "INFO" "Captive portal resolved - stopping periodic checks"
            break
        fi
    done
    
    log "INFO" "Periodic checks completed for $interface"
}

# =============================================================================
# HAUPTPROGRAMM
# =============================================================================

log "INFO" "=== Dispatch triggered: $1 $2 ==="

if [[ "$1" == wl* ]] && [ "$2" = "up" ]; then
    sleep 3
    
    if ! check_captive_portal; then
        log "INFO" "CAPTIVE PORTAL DETECTED! Opening browser..."
        
        read user display session_type <<< $(get_user_session)
        
        if [ -n "$user" ] && [ -n "$display" ]; then
            log "INFO" "Found user: $user, display: $display, type: $session_type"
            
            # Starte Firefox
            if start_firefox "$user" "$display" "$session_type"; then
                log "INFO" "Firefox successfully launched"
                
                # STARTE PERIODISCHE CHECKS IM HINTERGRUND
                log "INFO" "Starting periodic checks in background..."
                start_periodic_checks "$1" "$user" "$display" "$session_type" &
            else
                log "ERROR" "Failed to start Firefox"
            fi
        else
            log "WARNING" "No local user or display found for GUI access"
        fi
    else
        log "INFO" "No captive portal detected on connection start"
    fi

elif [[ "$1" == wl* ]] && [ "$2" = "down" ]]; then
    log "INFO" "WLAN interface $1 disconnected"

fi

log "INFO" "=== Completed ==="