// Copyright (c) Microsoft Corporation.
// Licensed under the MIT License.

using System;
using System.Collections.Generic;
using System.Collections.Specialized;
using System.Diagnostics;

namespace Microsoft.PowerShell.Commands.GetCounter
{
    public class CounterSet
    {
        internal CounterSet(string setName,
                            string machineName,
                            PerformanceCounterCategoryType categoryType,
                            string setHelp,
                            ref Dictionary<string, string[]> counterInstanceMapping)
        {
            CounterSetName = setName;
            if (machineName == null || machineName.Length == 0)
            {
                machineName = ".";
            }
            else
            {
                MachineName = machineName;
                if (!MachineName.StartsWith(@"\\", StringComparison.OrdinalIgnoreCase))
                {
                    MachineName = @"\\" + MachineName;
                }
            }

            CounterSetType = categoryType;
            Description = setHelp;
            CounterInstanceMapping = counterInstanceMapping;
        }

        public string CounterSetName { get; } = string.Empty;

        public string MachineName { get; } = ".";

        public PerformanceCounterCategoryType CounterSetType { get; }

        public string Description { get; } = string.Empty;

        internal Dictionary<string, string[]> CounterInstanceMapping { get; }

        public StringCollection Paths
        {
            get
            {
                StringCollection retColl = new();
                foreach (string counterName in this.CounterInstanceMapping.Keys)
                {
                    string path;
                    if (CounterInstanceMapping[counterName].Length != 0)
                    {
                        path = (MachineName == ".") ?
                          ("\\" + CounterSetName + "(*)\\" + counterName) :
                          (MachineName + "\\" + CounterSetName + "(*)\\" + counterName);
                    }
                    else
                    {
                        path = (MachineName == ".") ?
                         ("\\" + CounterSetName + "\\" + counterName) :
                         (MachineName + "\\" + CounterSetName + "\\" + counterName);
                    }

                    retColl.Add(path);
                }

                return retColl;
            }
        }

        public StringCollection PathsWithInstances
        {
            get
            {
                StringCollection retColl = new();
                foreach (string counterName in CounterInstanceMapping.Keys)
                {
                    foreach (string instanceName in CounterInstanceMapping[counterName])
                    {
                        string path = (MachineName == ".") ?
                          ("\\" + CounterSetName + "(" + instanceName + ")\\" + counterName) :
                          (MachineName + "\\" + CounterSetName + "(" + instanceName + ")\\" + counterName);
                        retColl.Add(path);
                    }
                }

                return retColl;
            }
        }
    }
}