using System;
using System.Collections.Generic;
using System.Collections.Immutable;
using System.Linq;
using BenchmarkDotNet.Attributes;
using BenchmarkDotNet.Running;
using PersistentMap;

// Ensure your PersistentMap namespace is included here
// using MyProject.Collections; 


[MemoryDiagnoser]
public class ImmutableBenchmark
{
    [Params(10, 100, 1000)]
    public int N { get; set; }

    [Params(1000)] 
    public int CollectionSize { get; set; }

    private ImmutableDictionary<string, string> _immutableDict;
    private ImmutableSortedDictionary<string, string> _immutableSortedDict;
    
    // 1. Add field for your map
    private PersistentMap<string, string, UnicodeStrategy> _persistentMap; 
    
    private string[] _searchKeys;

    [GlobalSetup]
    public void Setup()
    {
        var random = new Random(42);
        var data = new Dictionary<string, string>();

        while (data.Count < CollectionSize)
        {
            string key = GenerateRandomString(random, N);
            if (!data.ContainsKey(key))
            {
                data[key] = "value";
            }
        }

        _immutableDict = data.ToImmutableDictionary();
        _immutableSortedDict = data.ToImmutableSortedDictionary();

        // 2. Initialize your map. 
        // ASSUMPTION: Standard immutable pattern (Add returns new instance).
        // Adjust if you have a bulk loader like .ToPersistentMap() or a constructor.
        _persistentMap = PersistentMap<string, string, UnicodeStrategy>.Empty(new UnicodeStrategy());
        foreach (var kvp in data)
        {
            _persistentMap = _persistentMap.Set(kvp.Key, kvp.Value);
        }

        _searchKeys = data.Keys.ToArray();
    }

    [Benchmark(Baseline = true)]
    public string ImmutableDict_Lookup()
    {
        var key = _searchKeys[CollectionSize / 2];
        _immutableDict.TryGetValue(key, out var value);
        return value;
    }

    [Benchmark]
    public string ImmutableSortedDict_Lookup()
    {
        var key = _searchKeys[CollectionSize / 2];
        _immutableSortedDict.TryGetValue(key, out var value);
        return value;
    }

    // 3. Add the benchmark case
    [Benchmark]
    public string PersistentMap_Lookup()
    {
        var key = _searchKeys[CollectionSize / 2];
        // Adjust API call if your map uses a different method (e.g. Find, Get, indexer)
        _persistentMap.TryGetValue(key, out var value);
        return value;
    }

    private string GenerateRandomString(Random rng, int length)
    {
        const string chars = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";
        var buffer = new char[length];
        for (int i = 0; i < length; i++)
        {
            buffer[i] = chars[rng.Next(chars.Length)];
        }
        return new string(buffer);
    }
}