//
//  EmployeeCacheService.swift
//  EmployeeDirectory
//
//  Created by Matt Bruce on 2/6/25.
//

import Foundation
import UIKit

/// A service that handles image caching using memory, disk, and network in priority order.
public class EmployeeCacheService {
    // MARK: - Properties
    public static let shared = EmployeeCacheService() // Default shared instance

    /// Memory cache for storing images in RAM.
    private let emplyoees: Employees? = nil
    
    /// File manager for handling disk operations.
    private let fileManager = FileManager.default
    
    /// Directory where cached images are stored on disk.
    private let cacheDirectory: URL = {
        FileManager.default.urls(for: .cachesDirectory, in: .userDomainMask)[0]
    }()
    
    // MARK: - Initializer
    
    public init() {}

    public func save(from employees: Employees) throws {
        let data = try JSONEncoder().encode(employees)
        try data.write(to: cacheDirectory.appendingPathComponent("employees.json"))
    }

    public func load() throws -> Employees {
        let data = try Data(contentsOf: cacheDirectory.appendingPathComponent("employees.json"))
        return try JSONDecoder().decode(Employees.self, from: data)
    }
    
    public func clear() {
        try? FileManager.default.removeItem(at: cacheDirectory.appendingPathComponent("employees.json"))
    }
}