using System.Diagnostics.CodeAnalysis;
using System.Linq;
using Content.Shared.Emag.Systems;
using Content.Shared.Examine;
using Content.Shared.Lathe.Prototypes;
using Content.Shared.Localizations;
using Content.Shared.Materials;
using Content.Shared.Research.Prototypes;
using JetBrains.Annotations;
using Robust.Shared.Prototypes;
using Robust.Shared.Utility;

namespace Content.Shared.Lathe;

/// <summary>
/// This handles...
/// </summary>
public abstract partial class SharedLatheSystem : EntitySystem
{
    [Dependency] private SharedMaterialStorageSystem _materialStorage = default!;
    [Dependency] private EmagSystem _emag = default!;

    public readonly Dictionary<string, List<LatheRecipePrototype>> InverseRecipes = new();
    public const int MaxItemsPerRequest = 10_000;

    public override void Initialize()
    {
        base.Initialize();

        SubscribeLocalEvent<EmagLatheRecipesComponent, GotEmaggedEvent>(OnEmagged);
        SubscribeLocalEvent<LatheComponent, ExaminedEvent>(OnExamined);
        SubscribeLocalEvent<PrototypesReloadedEventArgs>(OnPrototypesReloaded);

        BuildInverseRecipeDictionary();
    }

    /// <summary>
    /// Get the set of all recipes that a lathe could possibly ever create (e.g., if all techs were unlocked).
    /// </summary>
    public HashSet<ProtoId<LatheRecipePrototype>> GetAllPossibleRecipes(LatheComponent component)
    {
        var recipes = new HashSet<ProtoId<LatheRecipePrototype>>();
        foreach (var pack in component.StaticPacks)
        {
            recipes.UnionWith(ProtoMan.Index(pack).Recipes);
        }

        foreach (var pack in component.DynamicPacks)
        {
            recipes.UnionWith(ProtoMan.Index(pack).Recipes);
        }

        return recipes;
    }

    /// <summary>
    /// Add every recipe in the list of recipe packs to a single hashset.
    /// </summary>
    public void AddRecipesFromPacks(HashSet<ProtoId<LatheRecipePrototype>> recipes, IEnumerable<ProtoId<LatheRecipePackPrototype>> packs)
    {
        foreach (var id in packs)
        {
            var pack = ProtoMan.Index(id);
            recipes.UnionWith(pack.Recipes);
        }
    }

    private void OnExamined(Entity<LatheComponent> ent, ref ExaminedEvent args)
    {
        if (!args.IsInDetailsRange)
            return;

        if (ent.Comp.ReagentOutputSlotId != null)
            args.PushMarkup(Loc.GetString("lathe-menu-reagent-slot-examine"));
    }

    [PublicAPI]
    public bool CanProduce(EntityUid uid, string recipe, int amount = 1, LatheComponent? component = null)
    {
        return ProtoMan.TryIndex<LatheRecipePrototype>(recipe, out var proto) && CanProduce(uid, proto, amount, component);
    }

    public bool CanProduce(EntityUid uid, LatheRecipePrototype recipe, int amount = 1, LatheComponent? component = null)
    {
        if (!Resolve(uid, ref component))
            return false;
        if (!HasRecipe(uid, recipe, component))
            return false;
        if (amount <= 0)
            return false;

        var materials = _materialStorage.GetStoredMaterials(uid);

        return HasMaterials(materials, recipe, component.MaterialUseMultiplier, amount);
    }

    /// <summary>
    /// Returns whether or not the given lathe can produce some number of a given recipe.
    /// </summary>
    /// <remarks>
    /// Useful for reducing material lookup with batched checks.
    /// </remarks>
    /// <param name="ent">The lathe that would produce the recipe.</param>
    /// <param name="recipe">The recipe to be produced.</param>
    /// <param name="materials">The set of materials to check.</param>
    /// <param name="amount">The number of times the recipe should be made.</param>
    public bool CanProduce(Entity<LatheComponent?> ent, LatheRecipePrototype recipe, Dictionary<ProtoId<MaterialPrototype>, int> materials, int amount)
    {
        if (!Resolve(ent, ref ent.Comp))
            return false;

        if (amount <= 0)
            return false;

        if (!HasRecipe(ent, recipe, ent.Comp))
            return false;

        return HasMaterials(materials, recipe, ent.Comp.MaterialUseMultiplier, amount);
    }

    /// <summary>
    /// Returns whether or not the given materials dictionary can produce <paramref name="amount"/> copies of <paramref name="recipe"/>.
    /// </summary>
    private bool HasMaterials(Dictionary<ProtoId<MaterialPrototype>, int> materials, LatheRecipePrototype recipe, float materialMultiplier, int amount = 1)
    {
        foreach (var (material, needed) in recipe.Materials)
        {
            if (!materials.TryGetValue(material, out var availableAmount))
                return false;

            var adjustedAmount = AdjustMaterial(needed, recipe.ApplyMaterialDiscount, materialMultiplier);

            if (availableAmount < adjustedAmount * amount)
                return false;
        }
        return true;
    }

    private void OnEmagged(EntityUid uid, EmagLatheRecipesComponent component, ref GotEmaggedEvent args)
    {
        if (!_emag.CompareFlag(args.Type, EmagType.Interaction))
            return;

        if (_emag.CheckFlag(uid, EmagType.Interaction))
            return;

        args.Handled = true;
    }

    public static int AdjustMaterial(int original, bool reduce, float multiplier)
        => reduce ? (int)MathF.Ceiling(original * multiplier) : original;

    protected abstract bool HasRecipe(EntityUid uid, LatheRecipePrototype recipe, LatheComponent component);

    private void OnPrototypesReloaded(PrototypesReloadedEventArgs obj)
    {
        if (!obj.WasModified<LatheRecipePrototype>())
            return;
        BuildInverseRecipeDictionary();
    }

    private void BuildInverseRecipeDictionary()
    {
        InverseRecipes.Clear();
        foreach (var latheRecipe in ProtoMan.EnumeratePrototypes<LatheRecipePrototype>())
        {
            if (latheRecipe.Result is not { } result)
                continue;

            InverseRecipes.GetOrNew(result).Add(latheRecipe);
        }
    }

    public bool TryGetRecipesFromEntity(string prototype, [NotNullWhen(true)] out List<LatheRecipePrototype>? recipes)
    {
        recipes = new();
        if (InverseRecipes.TryGetValue(prototype, out var r))
            recipes.AddRange(r);
        return recipes.Count != 0;
    }

    public string GetRecipeName(ProtoId<LatheRecipePrototype> proto)
    {
        return GetRecipeName(ProtoMan.Index(proto));
    }

    public string GetRecipeName(LatheRecipePrototype proto)
    {
        if (!string.IsNullOrWhiteSpace(proto.Name))
            return Loc.GetString(proto.Name);

        if (proto.Result is { } result)
        {
            return ProtoMan.Index(result).Name;
        }

        if (proto.ResultReagents is { } resultReagents)
        {
            return ContentLocalizationManager.FormatList(resultReagents
                .Select(p => Loc.GetString("lathe-menu-result-reagent-display", ("reagent", ProtoMan.Index(p.Key).LocalizedName), ("amount", p.Value)))
                .ToList());
        }

        return string.Empty;
    }

    [PublicAPI]
    public string GetRecipeDescription(ProtoId<LatheRecipePrototype> proto)
    {
        return GetRecipeDescription(ProtoMan.Index(proto));
    }

    public string GetRecipeDescription(LatheRecipePrototype proto)
    {
        if (!string.IsNullOrWhiteSpace(proto.Description))
            return Loc.GetString(proto.Description);

        if (proto.Result is { } result)
        {
            return ProtoMan.Index(result).Description;
        }

        if (proto.ResultReagents is { } resultReagents)
        {
            // We only use the first one for the description since these descriptions don't combine very well.
            var reagent = resultReagents.First().Key;
            return ProtoMan.Index(reagent).LocalizedDescription;
        }

        return string.Empty;
    }
}