using System.Collections.Generic;

namespace WhiteMagic.Hooking;

/// <summary>
/// Manages named, reversible byte patches against a <see cref="MemoryBase"/>.
/// Every patch records the bytes it replaced and can restore them later.
/// </summary>
public sealed class PatchManager
{
    private readonly MemoryBase _memory;
    private readonly Dictionary<string, Patch> _patches = new();

    /// <summary>Creates a patch manager bound to the supplied memory reader.</summary>
    public PatchManager(MemoryBase memory)
    {
        _memory = memory;
    }

    /// <summary>Creates a new patch and registers it with the manager.</summary>
    public Patch Create(string name, IntPtr address, byte[] patchBytes)
    {
        var patch = new Patch(_memory, name, address, patchBytes);
        _patches[name] = patch;
        return patch;
    }

    /// <summary>Looks up a patch by name.</summary>
    public Patch? this[string name]
    {
        get
        {
            _patches.TryGetValue(name, out Patch? patch);
            return patch;
        }
    }

    /// <summary>All patches registered in this manager.</summary>
    public IEnumerable<Patch> All => _patches.Values;

    /// <summary>Removes every applied patch.</summary>
    public void RestoreAll()
    {
        foreach (Patch patch in _patches.Values)
        {
            patch.Remove();
        }
    }
}