using System;
using static System.Buffers.Binary.BinaryPrimitives;

namespace PKHeX.Core
{
    public sealed class ConfigSave6 : SaveBlock
    {
        /* ===32 bits===
         * talkSpeed:2      0,1
         * battleAnim:1     2
         * battleStyle:1    3
         * unknown:4        4..7
         * battleBG:5       8..12
         * buttonMode:2     13,14
         * forcedSave:1     15
         * flag1:1          16
         * enablePSS:1      17
         * enablePR:1       18
         * unknown:14       19..31
         */

        public ConfigSave6(SAV6XY sav, int offset) : base(sav) => Offset = offset;
        public ConfigSave6(SAV6AO sav, int offset) : base(sav) => Offset = offset;

        public int ConfigValue
        {
            get => ReadInt32LittleEndian(Data.AsSpan(Offset));
            set => WriteInt32LittleEndian(Data.AsSpan(Offset), value);
        }

        public int TalkingSpeed
        {
            get => ConfigValue & 3;
            set => ConfigValue = (ConfigValue & ~3) | (value & 3);
        }

        public BattleAnimationSetting BattleAnimation
        {
            // Effects OFF = 1, Effects ON = 0
            get => (BattleAnimationSetting)((ConfigValue >> 2) & 1);
            set => ConfigValue = (ConfigValue & ~(1 << 2)) | ((byte)value << 2);
        }

        public BattleStyleSetting BattleStyle
        {
            // SET = 1, SWITCH = 0
            get => (BattleStyleSetting)((ConfigValue >> 3) & 1);
            set => ConfigValue = (ConfigValue & ~(1 << 3)) | ((byte)value << 3);
        }

        // UNKNOWN?

        public int BattleBackground
        {
            // Only values 0-14 are used.
            get => (ConfigValue >> 8) & 0x1F;
            set => ConfigValue = (ConfigValue & ~(0x1F << 8)) | (value << 8);
        }

        public int ButtonMode
        {
            get => (ConfigValue >> 13) & 3;
            set => ConfigValue = (ConfigValue & ~(1 << 13)) | (value << 13);
        }

        public int ForceSaveBeforeOnline
        {
            get => (ConfigValue >> 15) & 1;
            set => ConfigValue = (ConfigValue & ~(1 << 15)) | (value << 15);
        }

        public int EnableFlag1
        {
            get => (ConfigValue >> 16) & 1;
            set => ConfigValue = (ConfigValue & ~(1 << 16)) | (value << 16);
        }

        public int EnablePSSFlag
        {
            get => (ConfigValue >> 17) & 1;
            set => ConfigValue = (ConfigValue & ~(1 << 17)) | (value << 17);
        }

        public int EnableTrainerPRFlag
        {
            get => (ConfigValue >> 18) & 1;
            set => ConfigValue = (ConfigValue & ~(1 << 18)) | (value << 18);
        }

        // NOTE: BELOW COMES FROM LGPE. MAYBE THIS IS WHAT THEY USE THE FLAGS FOR?

        /// <summary>
        /// <see cref="LanguageID"/> for messages, stored with <see cref="LanguageID.UNUSED_6"/> skipped in the enumeration.
        /// </summary>
        public int Language
        {
            get => GetLanguageID((ConfigValue >> 4) & 0xF);
            set => ConfigValue = ((ConfigValue & ~0xF0) | SetLanguageID(value) << 4);
        }

        private static int GetLanguageID(int rawValue) => rawValue >= (int)LanguageID.UNUSED_6 ? rawValue + 1 : rawValue; // sets langBank to LanguageID
        private static int SetLanguageID(int rawValue) => rawValue > (int)LanguageID.UNUSED_6 ? rawValue - 1 : rawValue; // sets LanguageID to langBank

        public enum BattleAnimationSetting
        {
            EffectsON,
            EffectsOFF,
        }

        public enum BattleStyleSetting
        {
            SWITCH,
            SET,
        }
    }
}