using System;
using static PKHeX.Core.BinLinkerAccessor;

namespace PKHeX.Core;

/// <summary>
/// Loosely aggregated legality logic.
/// </summary>
public static partial class Legal
{
    // Gen 1
    internal static readonly Learnset[] LevelUpRB = LearnsetReader.GetArray(Util.GetBinaryResource("lvlmove_rb.pkl"), MaxSpeciesID_1);
    internal static readonly Learnset[] LevelUpY = LearnsetReader.GetArray(Util.GetBinaryResource("lvlmove_y.pkl"), MaxSpeciesID_1);

    // Gen 2
    internal static readonly EggMoves2[] EggMovesGS = EggMoves2.GetArray(Util.GetBinaryResource("eggmove_gs.pkl"), MaxSpeciesID_2);
    internal static readonly Learnset[] LevelUpGS = LearnsetReader.GetArray(Util.GetBinaryResource("lvlmove_gs.pkl"), MaxSpeciesID_2);
    internal static readonly EggMoves2[] EggMovesC = EggMoves2.GetArray(Util.GetBinaryResource("eggmove_c.pkl"), MaxSpeciesID_2);
    internal static readonly Learnset[] LevelUpC = LearnsetReader.GetArray(Util.GetBinaryResource("lvlmove_c.pkl"), MaxSpeciesID_2);

    // Gen 3
    internal static readonly Learnset[] LevelUpE = LearnsetReader.GetArray(Get(Util.GetBinaryResource("lvlmove_e.pkl"), "em"));
    internal static readonly Learnset[] LevelUpRS = LearnsetReader.GetArray(Get(Util.GetBinaryResource("lvlmove_rs.pkl"), "rs"));
    internal static readonly Learnset[] LevelUpFR = LearnsetReader.GetArray(Get(Util.GetBinaryResource("lvlmove_fr.pkl"), "fr"));
    internal static readonly Learnset[] LevelUpLG = LearnsetReader.GetArray(Get(Util.GetBinaryResource("lvlmove_lg.pkl"), "lg"));
    internal static readonly EggMoves6[] EggMovesRS = EggMoves6.GetArray(Get(Util.GetBinaryResource("eggmove_rs.pkl"), "rs"));

    // Gen 4
    internal static readonly Learnset[] LevelUpDP = LearnsetReader.GetArray(Get(Util.GetBinaryResource("lvlmove_dp.pkl"), "dp"));
    internal static readonly Learnset[] LevelUpPt = LearnsetReader.GetArray(Get(Util.GetBinaryResource("lvlmove_pt.pkl"), "pt"));
    internal static readonly Learnset[] LevelUpHGSS = LearnsetReader.GetArray(Get(Util.GetBinaryResource("lvlmove_hgss.pkl"), "hs"));
    internal static readonly EggMoves6[] EggMovesDPPt = EggMoves6.GetArray(Get(Util.GetBinaryResource("eggmove_dppt.pkl"), "dp"));
    internal static readonly EggMoves6[] EggMovesHGSS = EggMoves6.GetArray(Get(Util.GetBinaryResource("eggmove_hgss.pkl"), "hs"));

    // Gen 5
    internal static readonly Learnset[] LevelUpBW = LearnsetReader.GetArray(Get(Util.GetBinaryResource("lvlmove_bw.pkl"), "51"));
    internal static readonly Learnset[] LevelUpB2W2 = LearnsetReader.GetArray(Get(Util.GetBinaryResource("lvlmove_b2w2.pkl"), "52"));
    internal static readonly EggMoves6[] EggMovesBW = EggMoves6.GetArray(Get(Util.GetBinaryResource("eggmove_bw.pkl"), "bw"));

    // Gen 6
    internal static readonly EggMoves6[] EggMovesXY = EggMoves6.GetArray(Get(Util.GetBinaryResource("eggmove_xy.pkl"), "xy"));
    internal static readonly Learnset[] LevelUpXY = LearnsetReader.GetArray(Get(Util.GetBinaryResource("lvlmove_xy.pkl"), "xy"));
    internal static readonly EggMoves6[] EggMovesAO = EggMoves6.GetArray(Get(Util.GetBinaryResource("eggmove_ao.pkl"), "ao"));
    internal static readonly Learnset[] LevelUpAO = LearnsetReader.GetArray(Get(Util.GetBinaryResource("lvlmove_ao.pkl"), "ao"));

    // Gen 7
    internal static readonly EggMoves7[] EggMovesSM = EggMoves7.GetArray(Get(Util.GetBinaryResource("eggmove_sm.pkl"), "sm"));
    internal static readonly Learnset[] LevelUpSM = LearnsetReader.GetArray(Get(Util.GetBinaryResource("lvlmove_sm.pkl"), "sm"));
    internal static readonly EggMoves7[] EggMovesUSUM = EggMoves7.GetArray(Get(Util.GetBinaryResource("eggmove_uu.pkl"), "uu"));
    internal static readonly Learnset[] LevelUpUSUM = LearnsetReader.GetArray(Get(Util.GetBinaryResource("lvlmove_uu.pkl"), "uu"));
    internal static readonly Learnset[] LevelUpGG = LearnsetReader.GetArray(Get(Util.GetBinaryResource("lvlmove_gg.pkl"), "gg"));

    // Gen 8
    internal static readonly EggMoves7[] EggMovesSWSH = EggMoves7.GetArray(Get(Util.GetBinaryResource("eggmove_swsh.pkl"), "ss"));
    internal static readonly Learnset[] LevelUpSWSH = LearnsetReader.GetArray(Get(Util.GetBinaryResource("lvlmove_swsh.pkl"), "ss"));
    internal static readonly EggMoves6[] EggMovesBDSP = EggMoves6.GetArray(Get(Util.GetBinaryResource("eggmove_bdsp.pkl"), "bs"));
    internal static readonly Learnset[] LevelUpBDSP = LearnsetReader.GetArray(Get(Util.GetBinaryResource("lvlmove_bdsp.pkl"), "bs"));
    internal static readonly Learnset[] LevelUpLA = LearnsetReader.GetArray(Get(Util.GetBinaryResource("lvlmove_la.pkl"), "la"));
    internal static readonly Learnset[] MasteryLA = LearnsetReader.GetArray(Get(Util.GetBinaryResource("mastery_la.pkl"), "la"));

    internal static int GetMaxSpeciesOrigin(PKM pk)
    {
        if (pk.Format == 1)
            return MaxSpeciesID_1;
        if (pk.Format == 2 || pk.VC)
            return MaxSpeciesID_2;
        return GetMaxSpeciesOrigin(pk.Generation);
    }

    internal static int GetMaxSpeciesOrigin(int generation) => generation switch
    {
        1 => MaxSpeciesID_1,
        2 => MaxSpeciesID_2,
        3 => MaxSpeciesID_3,
        4 => MaxSpeciesID_4,
        5 => MaxSpeciesID_5,
        6 => MaxSpeciesID_6,
        7 => MaxSpeciesID_7b,
        8 => MaxSpeciesID_8a,
        _ => -1,
    };

    internal static int GetMaxLanguageID(int generation) => generation switch
    {
        1 => (int) LanguageID.Spanish, // 1-7 except 6
        3 => (int) LanguageID.Spanish, // 1-7 except 6
        2 => (int) LanguageID.Korean,
        4 => (int) LanguageID.Korean,
        5 => (int) LanguageID.Korean,
        6 => (int) LanguageID.Korean,
        7 => (int) LanguageID.ChineseT,
        8 => (int) LanguageID.ChineseT,
        _ => -1,
    };

    /// <summary>
    /// Checks if the relearn moves should be wiped.
    /// </summary>
    /// <remarks>Already checked for generations &lt; 8.</remarks>
    /// <param name="pk">Entity to check</param>
    internal static bool IsOriginalMovesetDeleted(this PKM pk)
    {
        if (pk.IsNative)
            return IsSideGameTransferDeletedMoveset(pk);
        return pk is IBattleVersion { BattleVersion: not 0 };
    }

    private static bool IsSideGameTransferDeletedMoveset(PKM pk) => pk switch
    {
        PA8 pa8 => !pa8.LA,
        PB8 pb8 => !pb8.BDSP,
        PK8 pk8 => pk8.IsSideTransfer,
        _ => false,
    };

    /// <summary>
    /// Indicates if PP Ups are available for use.
    /// </summary>
    /// <param name="pk">Entity to check</param>
    public static bool IsPPUpAvailable(PKM pk)
    {
        return pk is not PA8;
    }

    public static int GetMaxLengthOT(int generation, LanguageID language) => language switch
    {
        LanguageID.ChineseS or LanguageID.ChineseT => 6,
        LanguageID.Japanese or LanguageID.Korean => generation >= 6 ? 6 : 5,
        _ => generation >= 6 ? 12 : 7,
    };

    public static int GetMaxLengthNickname(int generation, LanguageID language) => language switch
    {
        LanguageID.ChineseS or LanguageID.ChineseT => 6,
        LanguageID.Japanese or LanguageID.Korean => generation >= 6 ? 6 : 5,
        _ => generation >= 6 ? 12 : 10,
    };

    public static bool GetIsFixedIVSequenceValidSkipRand(ReadOnlySpan<int> IVs, PKM pk, int max = 31)
    {
        for (int i = 0; i < 6; i++)
        {
            if ((uint) IVs[i] > max) // random
                continue;
            if (IVs[i] != pk.GetIV(i))
                return false;
        }
        return true;
    }

    public static bool GetIsFixedIVSequenceValidSkipRand(IndividualValueSet IVs, PKM pk, int max = 31)
    {
        // Template IVs not in the [0,max] range are random. Only check for IVs within the "specified" range.
        if ((uint)IVs.HP  <= max && IVs.HP  != pk.IV_HP ) return false;
        if ((uint)IVs.ATK <= max && IVs.ATK != pk.IV_ATK) return false;
        if ((uint)IVs.DEF <= max && IVs.DEF != pk.IV_DEF) return false;
        if ((uint)IVs.SPE <= max && IVs.SPE != pk.IV_SPE) return false;
        if ((uint)IVs.SPA <= max && IVs.SPA != pk.IV_SPA) return false;
        if ((uint)IVs.SPD <= max && IVs.SPD != pk.IV_SPD) return false;
        return true;
    }

    public static bool GetIsFixedIVSequenceValidNoRand(IndividualValueSet IVs, PKM pk)
    {
        if (IVs.HP  != pk.IV_HP ) return false;
        if (IVs.ATK != pk.IV_ATK) return false;
        if (IVs.DEF != pk.IV_DEF) return false;
        if (IVs.SPE != pk.IV_SPE) return false;
        if (IVs.SPA != pk.IV_SPA) return false;
        if (IVs.SPD != pk.IV_SPD) return false;
        return true;
    }

    public static bool IsMetAsEgg(PKM pk) => pk switch
    {
        PA8 or PK8 => pk.Egg_Location is not 0 || (pk.BDSP && pk.Egg_Day is not 0),
        PB8 pb8 => pb8.Egg_Location is not Locations.Default8bNone,
        _ => pk.Egg_Location is not 0,
    };
}