namespace PS.IPAM.Cmdlets;

using System;
using System.Collections.Generic;
using System.Management.Automation;
using PS.IPAM.Helpers;

/// <summary>
/// Retrieves subnet usage statistics from phpIPAM.
/// </summary>
[Cmdlet(VerbsCommon.Get, "SubnetUsage", DefaultParameterSetName = "ByID")]
public class GetSubnetUsageCmdlet : BaseCmdlet
{
    [Parameter(
        Mandatory = true,
        ValueFromPipeline = true,
        ValueFromPipelineByPropertyName = true,
        Position = 0,
        ParameterSetName = "ByCIDR",
        HelpMessage = "The subnet in CIDR notation.")]
    [ValidatePattern(@"^\d+\.\d+\.\d+\.\d+/\d{1,2}$")]
    [ValidateNotNullOrEmpty]
    public string? CIDR { get; set; }

    [Parameter(
        Mandatory = true,
        ValueFromPipeline = true,
        ValueFromPipelineByPropertyName = true,
        Position = 0,
        ParameterSetName = "ByID",
        HelpMessage = "The subnet ID.")]
    [ValidateNotNullOrEmpty]
    public int? Id { get; set; }

    [Parameter(
        Mandatory = true,
        ValueFromPipeline = true,
        Position = 0,
        ParameterSetName = "BySubnetObject",
        HelpMessage = "The subnet object.")]
    [ValidateNotNullOrEmpty]
    public Subnetwork? SubnetObject { get; set; }

    protected override void ProcessRecord()
    {
        try
        {
            var subnetId = GetSubnetId();
            var identifiers = new List<string> { subnetId.ToString(), "usage" };

            var result = RequestHelper.InvokeRequest(
                "GET", ApiController.Subnets, null, null, null, identifiers.ToArray()
            ).GetAwaiter().GetResult();

            WriteResult(result);
        }
        catch (Exception ex)
        {
            WriteError(new ErrorRecord(ex, "GetSubnetUsageError", ErrorCategory.InvalidOperation, null));
        }
    }

    private int GetSubnetId()
    {
        switch (ParameterSetName)
        {
            case "ByCIDR":
                var subnet = RequestHelper.InvokeRequest(
                    "GET", ApiController.Subnets, ModelType.Subnetwork, null, null,
                    new[] { "cidr", CIDR! }
                ).GetAwaiter().GetResult() as Subnetwork;

                if (subnet == null)
                {
                    throw new ItemNotFoundException($"Subnet '{CIDR}' not found.");
                }
                return subnet.Id;

            case "BySubnetObject":
                return SubnetObject!.Id;

            default:
                return Id!.Value;
        }
    }
}