import Foundation
import SwiftUI

/// Categorizes todo tasks into groups based on their due dates and completion status.
///
/// This enumeration provides a semantic grouping mechanism for organizing and filtering todo tasks throughout the application.
/// Each case represents a distinct category that helps users manage their tasks based on temporal relevance and completion state.
enum TodoGroup {
    /// Tasks that have been marked as done, regardless of due date.
    case completed
    /// Tasks with due dates in the past that remain incomplete.
    case overdue
    /// Tasks due on the current day that are not yet completed.
    case today
    /// Tasks due in the future that are not yet completed.
    case upcoming
}

// MARK: - Computed

extension TodoGroup {

    /// The color associated with the task group.
    var color: Color {
        switch self {
            case .completed: .gray
            case .overdue: .red
            case .today: .blue
            case .upcoming: .green
        }
    }

    /// The system icon name for the task group.
    var iconName: String {
        switch self {
            case .completed: "checkmark.circle.fill"
            case .overdue: "calendar.badge.exclamationmark"
            case .today: "calendar.badge.clock"
            case .upcoming: "calendar"
        }
    }

    /// The display title for the task group.
    var title: LocalizedStringKey {
        switch self {
            case .completed: "enumeration.todo-group.title.completed"
            case .overdue: "enumeration.todo-group.title.overdue"
            case .today: "enumeration.todo-group.title.today"
            case .upcoming: "enumeration.todo-group.title.upcoming"

        }
    }

}

// MARK: - CaseIterable

extension TodoGroup: CaseIterable {

    static var allCases: [TodoGroup] { [.today, .upcoming, .overdue, .completed] }

}

// MARK: - Identifiable

extension TodoGroup: Identifiable {

    var id: Self { self }

}