#!/usr/bin/env python3
"""
NetBox DHCP IP Reservation Script
Marks individual IPs .100-.150 in each subnet as reserved for DHCP
"""

import requests
import ipaddress
import sys
import os

# Configuration
NETBOX_URL = "https://netbox.pdmarf.co.uk"
NETBOX_TOKEN = os.environ.get("NETBOX_TOKEN") or sys.argv[1] if len(sys.argv) > 1 else None

if not NETBOX_TOKEN:
    print("Error: NetBox API token required")
    print("Usage: NETBOX_TOKEN='your-token' python3 sys-apps-netbox-reserve-dhcp-ips.py")
    print("   or: python3 sys-apps-netbox-reserve-dhcp-ips.py 'your-token'")
    sys.exit(1)

# API headers
headers = {
    "Authorization": f"Token {NETBOX_TOKEN}",
    "Content-Type": "application/json",
    "Accept": "application/json"
}

def get_all_prefixes():
    """Get all IPv4 prefixes from NetBox"""
    url = f"{NETBOX_URL}/api/ipam/prefixes/"
    params = {"family": 4, "limit": 1000}

    try:
        response = requests.get(url, headers=headers, params=params, verify=True)
        response.raise_for_status()
        return response.json()["results"]
    except requests.exceptions.RequestException as e:
        print(f"Error fetching prefixes: {e}")
        sys.exit(1)

def create_dhcp_ip(ip_address, prefix_id):
    """Create or update individual IP as DHCP reserved"""
    url = f"{NETBOX_URL}/api/ipam/ip-addresses/"

    data = {
        "address": f"{ip_address}/24",  # CIDR notation
        "status": "reserved",
        "dns_name": "",
        "description": "DHCP Pool - Reserved for dynamic assignment"
    }

    try:
        response = requests.post(url, headers=headers, json=data, verify=True)

        if response.status_code == 201:
            return "created"
        elif response.status_code == 400:
            error_detail = response.json()
            if "already exists" in str(error_detail).lower() or "duplicate" in str(error_detail).lower():
                return "exists"
            else:
                return f"error: {error_detail}"
        else:
            return f"error: HTTP {response.status_code}"
    except Exception as e:
        return f"error: {e}"

def reserve_dhcp_range(prefix_str, prefix_id):
    """Reserve IPs .100-.150 in a prefix"""
    try:
        network = ipaddress.ip_network(prefix_str, strict=False)

        # Calculate .100 and .150 addresses
        base_ip = str(network.network_address)
        octets = base_ip.split('.')

        created = 0
        exists = 0
        errors = 0

        # Create IPs from .100 to .150
        for i in range(100, 151):
            ip_octets = octets[:-1] + [str(i)]
            ip_address = '.'.join(ip_octets)

            # Validate IP is within network
            ip_addr = ipaddress.ip_address(ip_address)
            if ip_addr not in network:
                continue

            result = create_dhcp_ip(ip_address, prefix_id)

            if result == "created":
                created += 1
                if created % 10 == 0:  # Progress indicator
                    print(f"    ... {created} IPs created so far")
            elif result == "exists":
                exists += 1
            else:
                errors += 1
                if errors <= 3:  # Show first 3 errors only
                    print(f"    ✗ {ip_address}: {result}")

        return created, exists, errors

    except Exception as e:
        print(f"  ✗ Error processing {prefix_str}: {e}")
        return 0, 0, 0

def main():
    print(f"\nConnecting to NetBox: {NETBOX_URL}")
    print("=" * 60)
    print("This will create individual IP objects for .100-.150 in each subnet")
    print("Status: Reserved | Description: DHCP Pool")
    print("=" * 60)

    # Get all prefixes
    print("\nFetching prefixes...")
    prefixes = get_all_prefixes()

    # Filter to /24 subnets only (skip /16)
    prefixes = [p for p in prefixes if '/24' in p['prefix']]
    print(f"Found {len(prefixes)} /24 prefixes\n")

    # Process each prefix
    total_created = 0
    total_exists = 0
    total_errors = 0

    for prefix in prefixes:
        prefix_str = prefix["prefix"]
        prefix_id = prefix["id"]
        vlan_name = prefix.get("vlan", {}).get("name", "No VLAN") if prefix.get("vlan") else "No VLAN"

        print(f"Processing: {prefix_str} ({vlan_name})")
        created, exists, errors = reserve_dhcp_range(prefix_str, prefix_id)

        print(f"  ✓ Created: {created}, Already exists: {exists}, Errors: {errors}")

        total_created += created
        total_exists += exists
        total_errors += errors

    # Summary
    print("\n" + "=" * 60)
    print("Summary:")
    print(f"  ✓ Created: {total_created}")
    print(f"  ℹ️  Already existed: {total_exists}")
    print(f"  ✗ Errors: {total_errors}")
    print("=" * 60)

    print("\n✓ DHCP pool IPs reserved in NetBox!")
    print("   IPs .100-.150 are now marked as 'Reserved' status")
    print("   They will no longer show as 'Available' in the IP list")

if __name__ == "__main__":
    main()