using System.Collections.Frozen;
using Robust.Shared.Serialization;
using Robust.Shared.Utility;

namespace Content.Shared.Guidebook;

/// <summary>
/// Used by GuidebookDataSystem to hold data extracted from prototype values,
/// both for storage and for network transmission.
/// </summary>
[Serializable, NetSerializable]
[DataDefinition]
public sealed partial class GuidebookData
{
    /// <summary>
    /// Total number of data values stored.
    /// </summary>
    [DataField]
    public int Count { get; private set; }

    /// <summary>
    /// The data extracted by the system.
    /// </summary>
    /// <remarks>
    /// Structured as PrototypeName, ComponentName, FieldName, Value
    /// </remarks>
    [DataField]
    public Dictionary<string, Dictionary<string, Dictionary<string, object?>>> Data = [];

    /// <summary>
    /// The data extracted by the system, converted to a FrozenDictionary for faster lookup.
    /// </summary>
    public FrozenDictionary<string, FrozenDictionary<string, FrozenDictionary<string, object?>>> FrozenData;

    /// <summary>
    /// Has the data been converted to a FrozenDictionary for faster lookup?
    /// This should only be done on clients, as FrozenDictionary isn't serializable.
    /// </summary>
    public bool IsFrozen;

    /// <summary>
    /// Adds a new value using the given identifiers.
    /// </summary>
    public void AddData(string prototype, string component, string field, object? value)
    {
        if (IsFrozen)
            throw new InvalidOperationException("Attempted to add data to GuidebookData while it is frozen!");
        Data.GetOrNew(prototype).GetOrNew(component).Add(field, value);
        Count++;
    }

    /// <summary>
    /// Attempts to retrieve a value using the given identifiers.
    /// </summary>
    /// <returns>true if the value was retrieved, otherwise false</returns>
    public bool TryGetValue(string prototype, string component, string field, out object? value)
    {
        if (!IsFrozen)
            throw new InvalidOperationException("Freeze the GuidebookData before calling TryGetValue!");

        // Look in frozen dictionary
        if (FrozenData.TryGetValue(prototype, out var p)
            && p.TryGetValue(component, out var c)
            && c.TryGetValue(field, out value))
        {
            return true;
        }

        value = null;
        return false;
    }

    /// <summary>
    /// Deletes all data.
    /// </summary>
    public void Clear()
    {
        Data.Clear();
        Count = 0;
        IsFrozen = false;
    }

    public void Freeze()
    {
        var protos = new Dictionary<string, FrozenDictionary<string, FrozenDictionary<string, object?>>>();
        foreach (var (protoId, protoData) in Data)
        {
            var comps = new Dictionary<string, FrozenDictionary<string, object?>>();
            foreach (var (compId, compData) in protoData)
            {
                comps.Add(compId, FrozenDictionary.ToFrozenDictionary(compData));
            }
            protos.Add(protoId, FrozenDictionary.ToFrozenDictionary(comps));
        }
        FrozenData = FrozenDictionary.ToFrozenDictionary(protos);
        Data.Clear();
        IsFrozen = true;
    }
}