using System;
using System.Collections.Generic;
using Svrnty.CQRS.Events.Abstractions.Sagas;

namespace Svrnty.CQRS.Events.Sagas;

/// <summary>
/// In-memory implementation of saga data storage.
/// </summary>
public sealed class SagaData : ISagaData
{
    private readonly Dictionary<string, object> _data = new();

    /// <inheritdoc />
    public T? Get<T>(string key)
    {
        if (_data.TryGetValue(key, out var value))
        {
            if (value is T typedValue)
                return typedValue;

            // Attempt conversion
            try
            {
                return (T)Convert.ChangeType(value, typeof(T));
            }
            catch
            {
                return default;
            }
        }

        return default;
    }

    /// <inheritdoc />
    public void Set<T>(string key, T value)
    {
        if (value == null)
        {
            _data.Remove(key);
        }
        else
        {
            _data[key] = value;
        }
    }

    /// <inheritdoc />
    public bool Contains(string key)
    {
        return _data.ContainsKey(key);
    }

    /// <inheritdoc />
    public IDictionary<string, object> GetAll()
    {
        return new Dictionary<string, object>(_data);
    }

    /// <summary>
    /// Load data from dictionary.
    /// </summary>
    public void LoadFrom(IDictionary<string, object> data)
    {
        _data.Clear();
        foreach (var kvp in data)
        {
            _data[kvp.Key] = kvp.Value;
        }
    }
}