[
  {
    "name": "Network Address from Host IP",
    "description": r"""Calculates the network address from a host IP/MASK notation.

Given a host IP address and subnet mask in CIDR notation (e.g., 192.168.1.100/24),
this formula extracts the network address (e.g., 192.168.1.0/24).

Where:
- Host IP/MASK: IP address with CIDR subnet mask (e.g., 192.168.1.100/24)
- Network: The resulting network address in IP/MASK format (e.g., 192.168.1.0/24)

The network address is calculated by applying the subnet mask to zero out the host bits.""",
    "input": [
      {"name": "hostIP", "unit": "string"}
    ],
    "output": {"name": "network", "unit": "string"},
    "d4rtCode": r"""var parts = hostIP.split('/');
var ip = parts[0];
var mask = int.parse(parts[1]);
var octets = ip.split('.').map((e) => int.parse(e)).toList();
var hostBits = 32 - mask;
var shiftAmount = hostBits;
var networkValue = 0;
for (var i = 0; i < 4; i++) {
  networkValue = (networkValue << 8) | octets[i];
}
networkValue = (networkValue >> shiftAmount) << shiftAmount;
var networkOctets = [];
for (var i = 0; i < 4; i++) {
  networkOctets.insert(0, networkValue & 0xFF);
  networkValue = networkValue >> 8;
}
network = networkOctets.join('.') + '/' + mask.toString();""",
    "tags": ["networking", "ip", "subnetting", "cidr", "network"]
  }
]