using IBKRTrader.Core.Database;
using IBKRTrader.Core.Logging;

namespace IBKRTrader.Core.Budget;

/// <summary>
/// Verwaltet das Budget pro Modul.
/// Liest/schreibt core_budget.
/// </summary>
public class BudgetService
{
    private readonly DatabaseService _db;
    private readonly LoggingService  _logger;

    public BudgetService(DatabaseService db, LoggingService logger)
    {
        _db     = db;
        _logger = logger;
    }

    public async Task<decimal> GetAvailableBudgetAsync(string module)
    {
        var row = await _db.QueryFirstOrDefaultAsync<dynamic>(
            "SELECT total_budget, used_budget FROM `core_budget` WHERE module = @module",
            new { module });

        if (row == null) return 0;
        return (decimal)row.total_budget - (decimal)row.used_budget;
    }

    public async Task ReserveBudgetAsync(string module, decimal amount)
    {
        await _db.ExecuteAsync(
            @"INSERT INTO `core_budget` (module, used_budget)
              VALUES (@module, @amount)
              ON DUPLICATE KEY UPDATE used_budget = used_budget + @amount",
            new { module, amount });
    }

    public async Task ReleaseBudgetAsync(string module, decimal amount)
    {
        await _db.ExecuteAsync(
            @"UPDATE `core_budget`
              SET used_budget = GREATEST(0, used_budget - @amount)
              WHERE module = @module",
            new { module, amount });
    }
}