#!/bin/sh

# Configuration
URL="http://grav.wsn.fi/allowed-mac"
TEMP_FILE="/tmp/new_maclist.txt"
SORTED_NEW="/tmp/new_maclist_sorted.txt"
LOG_FILE="/tmp/logs.txt"
WEB_LINK="/www/logs.txt"
TARGET_SSID="Konepaja"

# --- Setup: Ensure Web Accessibility ---
# Check if the symbolic link exists and is a link (-L)
if [ ! -L "$WEB_LINK" ]; then
    echo "Web link for logs missing. Creating link..."
    # Remove if it exists as a regular file to avoid errors, then link
    rm -f "$WEB_LINK"
    ln -s "$LOG_FILE" "$WEB_LINK"
fi

# Ensure the log file exists so the web server doesn't 404
[ ! -f "$LOG_FILE" ] && touch "$LOG_FILE"

# --- Phase 1: Fetch and Sanitize ---
echo "Fetching MAC list from $URL..."

wget -qO- "$URL" | tr -d '\r' | tr 'a-z' 'A-Z' | grep -E '^([0-9A-F]{2}:){5}[0-9A-F]{2}' | sort | uniq > "$SORTED_NEW"

if [ ! -s "$SORTED_NEW" ]; then
    echo "Error: Could not retrieve MAC list or list is empty."
    rm -f "$SORTED_NEW"
    exit 1
fi

# --- Phase 2: Comparison and Update ---
sections=$(uci show wireless | grep "=wifi-iface" | cut -d'.' -f2 | cut -d'=' -f1)
any_change_detected=0

for section in $sections; do
    curr_ssid=$(uci -q get wireless."$section".ssid)
    
    if [ "$curr_ssid" = "$TARGET_SSID" ]; then
        # Get current list from UCI
        curr_macs=$(uci -q get wireless."$section".maclist | tr ' ' '\n' | tr 'a-z' 'A-Z' | sort | uniq)
        new_macs=$(cat "$SORTED_NEW")

        if [ "$curr_macs" = "$new_macs" ]; then
            echo "Interface $section is already up to date."
            continue
        fi

        echo "Change detected for $section. Updating..."
        any_change_detected=1

        # Modify UCI settings
        uci set wireless."$section".macfilter='allow'
        uci -q delete wireless."$section".maclist
        while IFS= read -r mac; do
            uci add_list wireless."$section".maclist="$mac"
        done < "$SORTED_NEW"
    fi
done

# --- Phase 3: Commit and Log ---
if [ "$any_change_detected" -eq 1 ]; then
    echo "Applying changes..."
    uci commit wireless
    /sbin/wifi reload
    
    # Append to RAM-based log
    echo "$(date '+%Y-%m-%d %H:%M:%S') - mac address list has been updated" >> "$LOG_FILE"
else
    echo "No changes detected. Flash memory saved."
fi

# Cleanup
rm -f "$SORTED_NEW"