#!/bin/bash
#
# Process Terminator Script for macOS
# This script forcibly terminates a process and all its descendant processes
#

# Check if PID argument is provided
if [ $# -ne 1 ]; then
    echo "Usage: $0 <PID>"
    exit 1
fi

PID=$1

# Validate that input is a valid PID (numeric)
if ! [[ "$PID" =~ ^[0-9]+$ ]]; then
    echo "Error: The PID must be a numeric value"
    exit 1
fi

# Check if the process exists
if ! ps -p $PID > /dev/null; then
    echo "Warning: No process found with PID $PID"
    exit 0
fi

# Recursive function to find and kill all descendant processes
kill_descendants() {
    local parent=$1
    # Use ps -eo pid,ppid for macOS compatibility
    local children=$(ps -eo pid=,ppid= | awk -v ppid=$parent '$2==ppid {print $1}')
    
    echo "Processing children of PID: $parent..."
    for child in $children; do
        kill_descendants "$child"
        echo "Terminating child process: $child"
        kill -9 "$child" 2>/dev/null || true
    done
}

echo "============================================"
echo "Starting termination of process $PID and all its descendants"
echo "============================================"

# Find and kill all descendant processes
kill_descendants "$PID"

# Finally kill the main process
echo "Terminating main process: $PID"
kill -9 "$PID" 2>/dev/null || true

echo "============================================"
echo "Process $PID and all its descendants have been terminated"
echo "============================================"

exit 0