// // Copyright (c) 2023 Timothy Schenk.Subject to the GNU AGPL Version 3 License.

using Microsoft.EntityFrameworkCore;
using NetCoreServer;
using Server.DB;
using Server.DB.Documents;
using Wonderking.Packets.Incoming;
using Wonderking.Packets.Outgoing;
using Wonderking.Packets.Outgoing.Data;

namespace Server.PacketHandlers;

public class ChannelSelectionHandler : IPacketHandler<ChannelSelectionPacket>
{
    private readonly WonderkingContext _wonderkingContext;

    public ChannelSelectionHandler(WonderkingContext wonderkingContext)
    {
        _wonderkingContext = wonderkingContext;
    }

    public async Task HandleAsync(ChannelSelectionPacket packet, TcpSession session)
    {
        var authSession = (AuthSession)session;
        ChannelSelectionResponsePacket responsePacket;
        var guildNameResponsePacket = new CharacterSelectionSetGuildNamePacket { GuildNames = Array.Empty<string>() };

        var account = await _wonderkingContext.Accounts
            .FirstOrDefaultAsync(a => a.Id == authSession.AccountId);
        if (account != null && account.Characters.Count > 0)
        {
            responsePacket = new ChannelSelectionResponsePacket
            {
                ChannelIsFullFlag = 0,
                Endpoint = "127.0.0.1",
                Port = 2000,
                Characters = await _wonderkingContext.Characters.AsNoTracking()
                    .Where(c => c.Account.Id == authSession.AccountId)
                    .Select(c =>
                        new CharacterData
                        {
                            Name = c.Name,
                            Job = c.JobData,
                            Gender = c.Gender,
                            Level = c.Level,
                            // TODO: Calculate instead of clamping based on max experience for level
                            Experience = Math.Clamp(c.Experience, 0, 100),
                            Stats = c.BaseStats,
                            Health = c.Health,
                            Mana = c.Mana,
                            EquippedItems = GetItemIDsByInventoryTab(c.InventoryItems
                                .Where(item => item.InventoryTab == InventoryTab.WornEquipment)
                                .Select(item => new Tuple<ushort, byte>(item.ItemId, item.Slot)).AsEnumerable()),
                            EquippedCashItems = GetItemIDsByInventoryTab(c.InventoryItems
                                .Where(item => item.InventoryTab == InventoryTab.WornCashEquipment)
                                .Select(item => new Tuple<ushort, byte>(item.ItemId, item.Slot)).AsEnumerable())
                        })
                    .ToArrayAsync()
            };

            guildNameResponsePacket.GuildNames = await _wonderkingContext.Characters
                .Where(c => c.Account.Id == authSession.AccountId)
                .Where(c => c.Guild != null)
                .Select(character => character.Guild.Name).ToArrayAsync();
        }
        else
        {
            responsePacket = new ChannelSelectionResponsePacket
            {
                ChannelIsFullFlag = 0,
                Endpoint = "127.0.0.1",
                Port = 2000,
                Characters = Array.Empty<CharacterData>()
            };
        }

        await authSession.SendAsync(responsePacket);
        if (guildNameResponsePacket.GuildNames.Length > 0 &&
            guildNameResponsePacket.GuildNames.Select(n => n != string.Empty).Any())
        {
            await authSession.SendAsync(guildNameResponsePacket);
        }
    }

    private static ushort[] GetItemIDsByInventoryTab(IEnumerable<Tuple<ushort, byte>> items)
    {
        var ids = new ushort[20];
        ids.AsSpan().Clear();

        foreach (var item in items)
        {
            if (item.Item2 > 20)
            {
                continue;
            }

            ids[item.Item2] = item.Item1;
        }

        return ids;
    }
}