using Predictalytics.Domain.Entities;
using Predictalytics.Domain.Enums;
using Predictalytics.Domain.Interfaces;
using Microsoft.EntityFrameworkCore;

namespace Predictalytics.Infrastructure.Data.Repositories;

public class TradeRepository : ITradeRepository
{
    private readonly AppDbContext _db;
    public TradeRepository(AppDbContext db) => _db = db;

    public async Task<Trade?> GetByPlatformTradeIdAsync(PlatformType platform, string platformTradeId, CancellationToken ct = default)
        => await _db.Trades.FirstOrDefaultAsync(t => t.Platform == platform && t.PlatformTradeId == platformTradeId, ct);

    public async Task<IReadOnlyList<Trade>> GetByTraderIdAsync(int traderId, int skip = 0, int take = 50, CancellationToken ct = default)
        => await _db.Trades.Include(t => t.Trader).Where(t => t.TraderId == traderId)
            .OrderByDescending(t => t.ExecutedAt).Skip(skip).Take(take).ToListAsync(ct);

    public async Task<IReadOnlyList<Trade>> GetByDbMarketIdAsync(int dbMarketId, int skip = 0, int take = 50, CancellationToken ct = default)
        => await _db.Trades.Include(t => t.Trader).Where(t => t.DbMarketId == dbMarketId)
            .OrderByDescending(t => t.ExecutedAt).Skip(skip).Take(take).ToListAsync(ct);

    public async Task<IReadOnlyList<Trade>> GetByMarketIdAsync(string platformMarketId, int skip = 0, int take = 50, CancellationToken ct = default)
        => await _db.Trades.Include(t => t.Trader).Where(t => t.MarketId == platformMarketId)
            .OrderByDescending(t => t.ExecutedAt).Skip(skip).Take(take).ToListAsync(ct);

    public async Task<IReadOnlyList<Trade>> GetRecentAsync(int count = 50, PlatformType? platform = null, CancellationToken ct = default)
    {
        var q = _db.Trades.Include(t => t.Trader).AsQueryable();
        if (platform.HasValue) q = q.Where(t => t.Platform == platform.Value);
        return await q.OrderByDescending(t => t.ExecutedAt).Take(count).ToListAsync(ct);
    }

    public async Task<IReadOnlyList<Trade>> GetLargestAsync(int count = 5, DateTime? since = null, CancellationToken ct = default)
    {
        var q = _db.Trades.Include(t => t.Trader).AsQueryable();
        if (since.HasValue) q = q.Where(t => t.ExecutedAt >= since.Value);
        return await q.OrderByDescending(t => t.Amount).Take(count).ToListAsync(ct);
    }

    public async Task<int> GetCountAsync(int? traderId = null, CancellationToken ct = default)
    {
        var q = _db.Trades.AsQueryable();
        if (traderId.HasValue) q = q.Where(t => t.TraderId == traderId.Value);
        return await q.CountAsync(ct);
    }

    public async Task AddRangeAsync(IEnumerable<Trade> trades, CancellationToken ct = default)
    {
        foreach (var t in trades)
        {
            t.Outcome = StringHelper.Truncate(t.Outcome, 128) ?? "";
            t.PlatformTradeId = StringHelper.Truncate(t.PlatformTradeId, 256) ?? "";
            t.MarketId = StringHelper.Truncate(t.MarketId, 66) ?? "";
            t.AssetId = StringHelper.Truncate(t.AssetId, 80) ?? "";
            if (t.TransactionHash != null)
                t.TransactionHash = StringHelper.Truncate(t.TransactionHash, 66);
        }

        try
        {
            _db.Trades.AddRange(trades);
            await _db.SaveChangesAsync(ct);
        }
        catch
        {
            foreach (var t in trades)
            {
                try { _db.Entry(t).State = EntityState.Detached; } catch { }
            }
            throw;
        }
    }

    public async Task<decimal> GetTotalVolumeAsync(DateTime? since = null, CancellationToken ct = default)
    {
        var q = _db.Trades.AsQueryable();
        if (since.HasValue) q = q.Where(t => t.ExecutedAt >= since.Value);
        return await q.SumAsync(t => t.Amount, ct);
    }
    
    public async Task<IReadOnlyList<Trade>> GetOrphanedTradesAsync(int limit, CancellationToken ct = default)
    {
        return await _db.Trades
            .Where(t => t.MarketOutcomeId == null && !string.IsNullOrEmpty(t.AssetId))
            .OrderByDescending(t => t.ExecutedAt)
            .Take(limit)
            .ToListAsync(ct);
    }
    
    public async Task<HashSet<string>> GetKnownPlatformTradeIdsAsync(PlatformType platform, int traderId, IEnumerable<string> platformTradeIds, CancellationToken ct = default)
    {
        var idList = platformTradeIds.ToList();
        if (idList.Count == 0) return new HashSet<string>();

        var ids = await _db.Trades
            .Where(t => t.Platform == platform && t.TraderId == traderId && idList.Contains(t.PlatformTradeId))
            .Select(t => t.PlatformTradeId)
            .ToListAsync(ct);
        return new HashSet<string>(ids);
    }

    public async Task UpdateAsync(Trade trade, CancellationToken ct = default)
    {
        trade.Outcome = StringHelper.Truncate(trade.Outcome, 128) ?? "";
        trade.PlatformTradeId = StringHelper.Truncate(trade.PlatformTradeId, 256) ?? "";
        trade.MarketId = StringHelper.Truncate(trade.MarketId, 66) ?? "";
        trade.AssetId = StringHelper.Truncate(trade.AssetId, 80) ?? "";

        _db.Trades.Update(trade);
        await _db.SaveChangesAsync(ct);
    }
}