using System;
using System.Collections.Generic;

namespace PKHeX.Core;

/// <summary>
/// Bundles raw string inputs into lists that can be used in data binding.
/// </summary>
public sealed class GameDataSource
{
    public static readonly IReadOnlyList<ComboItem> Regions = new List<ComboItem>
    {
        new ("Japan (日本)",      0),
        new ("Americas (NA/SA)",  1),
        new ("Europe (EU/AU)",    2),
        new ("China (中国大陆)",   4),
        new ("Korea (한국)",       5),
        new ("Taiwan (香港/台灣)", 6),
    };

    private static readonly List<ComboItem> LanguageList = new()
    {
        new ComboItem("JPN (日本語)",   (int)LanguageID.Japanese),
        new ComboItem("ENG (English)",  (int)LanguageID.English),
        new ComboItem("FRE (Français)", (int)LanguageID.French),
        new ComboItem("ITA (Italiano)", (int)LanguageID.Italian),
        new ComboItem("GER (Deutsch)",  (int)LanguageID.German),
        new ComboItem("ESP (Español)",  (int)LanguageID.Spanish),
        new ComboItem("KOR (한국어)",    (int)LanguageID.Korean),
        new ComboItem("CHS (简体中文)",  (int)LanguageID.ChineseS),
        new ComboItem("CHT (繁體中文)",  (int)LanguageID.ChineseT),
    };

    public GameDataSource(GameStrings s)
    {
        Strings = s;
        BallDataSource = GetBalls(s.itemlist);
        SpeciesDataSource = Util.GetCBList(s.specieslist);
        NatureDataSource = Util.GetCBList(s.natures);
        AbilityDataSource = Util.GetCBList(s.abilitylist);
        GroundTileDataSource = Util.GetUnsortedCBList(s.groundtiletypes, GroundTileTypeExtensions.ValidTileTypes);

        var moves = Util.GetCBList(s.movelist);
        HaXMoveDataSource = moves;
        var legal = new List<ComboItem>(moves.Count);
        foreach (var m in moves)
        {
            if (MoveInfo.IsMoveKnowable((ushort)m.Value))
                legal.Add(m);
        }
        LegalMoveDataSource = legal;

        var games = GetVersionList(s);
        VersionDataSource = games;

        Met = new MetDataSource(s);

        Empty = new ComboItem(s.itemlist[0], 0);
        games[^1] = Empty;
    }

    /// <summary> Strings that this object's lists were generated with. </summary>
    public readonly GameStrings Strings;

    /// <summary> Contains Met Data lists to source lists from. </summary>
    public readonly MetDataSource Met;

    /// <summary> Represents "(None)", localized to this object's language strings. </summary>
    public readonly ComboItem Empty;

    public readonly IReadOnlyList<ComboItem> SpeciesDataSource;
    public readonly IReadOnlyList<ComboItem> BallDataSource;
    public readonly IReadOnlyList<ComboItem> NatureDataSource;
    public readonly IReadOnlyList<ComboItem> AbilityDataSource;
    public readonly IReadOnlyList<ComboItem> VersionDataSource;
    public readonly IReadOnlyList<ComboItem> LegalMoveDataSource;
    public readonly IReadOnlyList<ComboItem> HaXMoveDataSource;
    public readonly IReadOnlyList<ComboItem> GroundTileDataSource;

    private static IReadOnlyList<ComboItem> GetBalls(string[] itemList)
    {
        // ignores Poke/Great/Ultra
        ReadOnlySpan<ushort> ball_nums = stackalloc ushort[] { 007, 576, 013, 492, 497, 014, 495, 493, 496, 494, 011, 498, 008, 006, 012, 015, 009, 005, 499, 010, 001, 016, 851, 1785, 1710, 1711, 1712, 1713, 1746, 1747, 1748, 1749, 1750, 1771 };
        ReadOnlySpan<byte>   ball_vals = stackalloc   byte[] { 007, 025, 013, 017, 022, 014, 020, 018, 021, 019, 011, 023, 008, 006, 012, 015, 009, 005, 024, 010, 001, 016, 026, 0027, 0028, 0029, 0030, 0031, 0032, 0033, 0034, 0035, 0036, 0037 };
        return Util.GetVariedCBListBall(itemList, ball_nums, ball_vals);
    }

    private static ComboItem[] GetVersionList(GameStrings s)
    {
        var list = s.gamelist;
        ReadOnlySpan<byte> games = stackalloc byte[]
        {
            50, 51, // 9 sv
            47,     // 8 legends arceus
            48, 49, // 8 bdsp
            44, 45, // 8 swsh
            42, 43, // 7 gg
            30, 31, // 7 sm
            32, 33, // 7 usum
            24, 25, // 6 xy
            27, 26, // 6 oras
            21, 20, // 5 bw
            23, 22, // 5 b2w2
            10, 11, 12, // 4 dppt
            07, 08, // 4 hgss
            02, 01, 03, // 3 rse
            04, 05, // 3 frlg
            15,     // 3 cxd

            39, 40, 41, // 7vc2
            35, 36, 37, 38, // 7vc1
            34, // 7go

            00,
        };

        return Util.GetUnsortedCBList(list, games);
    }

    public List<ComboItem> GetItemDataSource(GameVersion game, EntityContext context, IReadOnlyList<ushort> allowed, bool HaX = false)
    {
        var items = Strings.GetItemStrings(context, game);
        return HaX ? Util.GetCBList(items) : Util.GetCBList(items, allowed);
    }

    public static IReadOnlyList<ComboItem> LanguageDataSource(int gen)
    {
        var languages = new List<ComboItem>(LanguageList);
        if (gen == 3)
            languages.RemoveAll(l => l.Value >= (int)LanguageID.Korean);
        else if (gen < 7)
            languages.RemoveAll(l => l.Value > (int)LanguageID.Korean);
        return languages;
    }
}