using FinlyticTrades.Database;
using FinlyticTrades.Entities;
using Microsoft.EntityFrameworkCore;

namespace FinlyticTrades.Services;

public interface ISettingsDbService
{
    /// <summary>
    /// Gets the current settings.
    /// </summary>
    Task<TradesSettingsEntity> GetSettingsAsync();
    /// <summary>
    /// Saves the provided settings.
    /// </summary>
    Task<TradesSettingsEntity> SaveSettingsAsync(TradesSettingsEntity settings);
    /// <summary>
    /// Updates settings from a dictionary of key-value pairs.
    /// </summary>
    Task UpdateSettingsFromDictionaryAsync(Dictionary<string, string> dictionary);
}

public class SettingsDbService : ISettingsDbService
{
    private readonly TradesDbContext _context;

    /// <summary>
    /// Initializes a new instance of the SettingsDbService class.
    /// </summary>
    public SettingsDbService(TradesDbContext context)
    {
        _context = context;
    }

    /// <summary>
    /// Gets the current settings.
    /// </summary>
    public async Task<TradesSettingsEntity> GetSettingsAsync()
    {
        var settings = await _context.Settings.AsNoTracking().FirstOrDefaultAsync();
        if (settings == null)
        {
            settings = new TradesSettingsEntity { Id = Guid.NewGuid() };
            _context.Settings.Add(settings);
            await _context.SaveChangesAsync();
            _context.ChangeTracker.Clear();
        }
        return settings;
    }

    /// <summary>
    /// Saves the provided settings.
    /// </summary>
    public async Task<TradesSettingsEntity> SaveSettingsAsync(TradesSettingsEntity settings)
    {
        var existing = await _context.Settings.FirstOrDefaultAsync();
        if (existing == null)
        {
            if (settings.Id == Guid.Empty) settings.Id = Guid.NewGuid();
            _context.Settings.Add(settings);
        }
        else
        {
            existing.AtrStopLossMultiplier = settings.AtrStopLossMultiplier;
            existing.RiskPerTradePercentage = settings.RiskPerTradePercentage;
            existing.MaxOpenPositions = settings.MaxOpenPositions;
            existing.UpdatedAt = settings.UpdatedAt;
            _context.Settings.Update(existing);
        }
        await _context.SaveChangesAsync();
        return settings;
    }

    /// <summary>
    /// Updates settings from a dictionary of key-value pairs.
    /// </summary>
    public async Task UpdateSettingsFromDictionaryAsync(Dictionary<string, string> dictionary)
    {
        var settings = await GetSettingsAsync();

        foreach (var (key, value) in dictionary)
        {
            if (string.Equals(key, "AtrStopLossMultiplier", StringComparison.OrdinalIgnoreCase) && double.TryParse(value, out var atr))
                settings.AtrStopLossMultiplier = atr;
            else if (string.Equals(key, "RiskPerTradePercentage", StringComparison.OrdinalIgnoreCase) && double.TryParse(value, out var risk))
                settings.RiskPerTradePercentage = risk;
            else if (string.Equals(key, "MaxOpenPositions", StringComparison.OrdinalIgnoreCase) && int.TryParse(value, out var maxPos))
                settings.MaxOpenPositions = maxPos;
        }

        settings.UpdatedAt = DateTime.UtcNow;
        await SaveSettingsAsync(settings);
    }
}