using System.ComponentModel.DataAnnotations;
using System.ComponentModel.DataAnnotations.Schema;

namespace MoneyMap.Models;

public enum BudgetPeriod
{
    Weekly = 0,
    Monthly = 1,
    Yearly = 2
}

/// <summary>
/// Represents a spending budget for a category or total spending.
/// When Category is null, this is a "Total" budget that tracks all spending.
/// </summary>
public class Budget
{
    [Key]
    public int Id { get; set; }

    /// <summary>
    /// The category this budget applies to.
    /// Null means this is a total spending budget (all categories combined).
    /// </summary>
    [MaxLength(100)]
    public string? Category { get; set; }

    /// <summary>
    /// The budget limit amount (positive value).
    /// </summary>
    [Column(TypeName = "decimal(18,2)")]
    public decimal Amount { get; set; }

    /// <summary>
    /// The time period for this budget (Weekly, Monthly, Yearly).
    /// </summary>
    public BudgetPeriod Period { get; set; } = BudgetPeriod.Monthly;

    /// <summary>
    /// When the budget becomes effective. Used to calculate period boundaries.
    /// </summary>
    public DateTime StartDate { get; set; } = DateTime.Today;

    /// <summary>
    /// Whether this budget is currently active.
    /// </summary>
    public bool IsActive { get; set; } = true;

    /// <summary>
    /// Optional notes about this budget.
    /// </summary>
    [MaxLength(500)]
    public string? Notes { get; set; }

    // Computed properties
    [NotMapped]
    public bool IsTotalBudget => Category == null;

    [NotMapped]
    public string DisplayName => Category ?? "Total Spending";
}