using System;
using System.Collections.Generic;
using System.Collections.Immutable;
using System.IO;
using System.Linq;
using System.Text.Json;
using PkmnLib.Dataloader.Models;
using PkmnLib.Static;
using PkmnLib.Static.Libraries;
using PkmnLib.Static.Moves;
using PkmnLib.Static.Utils;

namespace PkmnLib.Dataloader;

public static class MoveDataLoader
{
    public static MoveLibrary LoadMoves(Stream stream, TypeLibrary typeLibrary)
    {
        var library = new MoveLibrary();
        var objects = JsonSerializer.Deserialize<SerializedMoveDataWrapper>(stream,
            new JsonSerializerOptions()
            {
                PropertyNameCaseInsensitive = true,
            });
        if (objects == null)
            throw new InvalidDataException("Move data is empty.");
        var moves = objects.Data.Select(x => DeserializeMove(x, typeLibrary));
        foreach (var m in moves)
            library.Add(m);
        return library;
    }

    public static Func<SerializedMove, StringKey, TypeIdentifier, MoveCategory, byte, byte, byte, MoveTarget, sbyte,
        ISecondaryEffect?, IEnumerable<StringKey>, MoveDataImpl> MoveConstructor =
    (serialized, name, moveType, category, basePower, accuracy, baseUsages, target, priority, secondaryEffect,
        flags) => new MoveDataImpl(name, moveType, category, basePower, accuracy, baseUsages, target, priority,
        secondaryEffect, flags);

    private static MoveDataImpl DeserializeMove(SerializedMove serialized, TypeLibrary typeLibrary)
    {
        var type = serialized.Type;
        var power = serialized.Power;
        var pp = serialized.PP;
        var accuracy = serialized.Accuracy;
        var priority = serialized.Priority;
        var target = serialized.Target;
        var category = serialized.Category;
        var flags = serialized.Flags;
        var effect = serialized.Effect;

        if (target.Equals("self", StringComparison.InvariantCultureIgnoreCase))
            target = "selfUse";

        if (!typeLibrary.TryGetTypeIdentifier(type, out var typeIdentifier))
            throw new InvalidDataException($"Type {type} is not a valid type.");
        if (!Enum.TryParse<MoveCategory>(category, true, out var categoryEnum))
            throw new InvalidDataException($"Category {category} is not a valid category.");
        if (!Enum.TryParse<MoveTarget>(target, true, out var targetEnum))
            throw new InvalidDataException($"Target {target} is not a valid target.");
        var secondaryEffect = ParseEffect(effect);

        var move = MoveConstructor(serialized, serialized.Name, typeIdentifier, categoryEnum, power, accuracy, pp, targetEnum,
            priority, secondaryEffect, flags.Select(x => (StringKey)x).ToImmutableHashSet());
        return move;
    }

    private static ISecondaryEffect? ParseEffect(SerializedMoveEffect? effect)
    {
        if (effect == null)
            return null;
        var name = effect.Name;
        var chance = effect.Chance;
        var parameters = effect.Parameters?.ToDictionary(x => (StringKey)x.Key, x => x.Value.ToParameter()) ??
                         new Dictionary<StringKey, object?>();
        return new SecondaryEffectImpl(chance, name, parameters);
    }
}