Change time zone based on system IP

auto_zone.sh

#!/bin/bash

# Default timezone for --default option
DEFAULT_TZ="Asia/Tehran"

# Function to display help
display_help() {
    echo "Usage: $0 [OPTION]"
    echo
    echo "Automatically detect and update timezone based on IP address location."
    echo
    echo "Options:"
    echo "  -h, --help      Display this help message and exit"
    echo "  --default       Set timezone to $DEFAULT_TZ without detection"
    echo
    echo "When run without options, the script will:"
    echo "1. Detect your current IP address and location"
    echo "2. Show your country and capital city"
    echo "3. Compare with current system timezone"
    echo "4. Prompt to update timezone if different"
    exit 0
}

# Function to get current public IP information
get_ip_info() {
    echo "Detecting your IP information..."
    ip_info=$(curl -s https://ipinfo.io/json)
    
    if [ -z "$ip_info" ]; then
        echo "Error: Could not fetch IP information. Check your internet connection."
        exit 1
    fi
    
    ip=$(echo "$ip_info" | jq -r '.ip')
    country=$(echo "$ip_info" | jq -r '.country')
    city=$(echo "$ip_info" | jq -r '.city')
    timezone=$(echo "$ip_info" | jq -r '.timezone')
    
    echo "----------------------------------------"
    echo "Your current IP address: $ip"
    echo "Country: $country"
    echo "City: $city"
    echo "Detected timezone: $timezone"
    echo "----------------------------------------"
}

# Function to get the current system timezone
get_current_timezone() {
    if [ -f /etc/localtime ]; then
        current_tz=$(readlink /etc/localtime | sed 's|/usr/share/zoneinfo/||')
        if [ -z "$current_tz" ]; then
            current_tz=$(timedatectl | grep "Time zone" | awk '{print $3}')
        fi
        echo "$current_tz"
    else
        current_tz=$(timedatectl | grep "Time zone" | awk '{print $3}')
        echo "$current_tz"
    fi
}

# Function to change timezone
change_timezone() {
    local new_tz=$1
    
    echo "Changing timezone to $new_tz..."
    
    # Check if the timezone file exists
    if [ ! -f "/usr/share/zoneinfo/$new_tz" ]; then
        echo "Error: Timezone $new_tz not found in /usr/share/zoneinfo/"
        return 1
    fi
    
    # Change the timezone
    sudo unlink /etc/localtime 2>/dev/null
    sudo ln -s "/usr/share/zoneinfo/$new_tz" /etc/localtime
    
    # Verify the change
    current_tz=$(get_current_timezone)
    if [ "$current_tz" == "$new_tz" ]; then
        echo "Timezone successfully changed to $new_tz"
        echo "Current time: $(date)"
    else
        echo "Warning: Timezone change might not have worked correctly."
        echo "Current timezone is: $current_tz"
    fi
}

# Check if jq is installed (for JSON parsing)
check_dependencies() {
    if ! command -v jq &> /dev/null; then
        echo "Error: jq is not installed. Please install it first."
        echo "For Debian/Ubuntu: sudo apt-get install jq"
        echo "For RHEL/CentOS: sudo yum install jq"
        exit 1
    fi

    if ! command -v curl &> /dev/null; then
        echo "Error: curl is not installed. Please install it first."
        exit 1
    fi
}

# Parse command line arguments
while [[ "$#" -gt 0 ]]; do
    case $1 in
        -h|--help)
            display_help
            ;;
        --default)
            change_timezone "$DEFAULT_TZ"
            exit 0
            ;;
        *)
            echo "Unknown parameter: $1"
            display_help
            exit 1
            ;;
    esac
    shift
done

# Main script
check_dependencies
get_ip_info

current_tz=$(get_current_timezone)
echo "Current system timezone: $current_tz"

if [ "$timezone" == "$current_tz" ]; then
    echo "Your timezone is already set correctly for your detected location."
    exit 0
fi

echo "Your timezone ($current_tz) doesn't match your detected location ($timezone)."
read -p "Do you want to change your timezone to $timezone? [Y/n] " answer

answer=${answer:-Y}  # Default to Y if empty
case ${answer^^} in
    Y|YES|"")
        change_timezone "$timezone"
        ;;
    *)
        echo "Timezone not changed."
        ;;
esac