import Foundation

struct Cap {

    /// The unique number of the cap
    let id: Int

    /// The name of the cap
    var name: String

    /// The name of the cap without special characters
    var cleanName: String

    /// The number of images existing for the cap
    var imageCount: Int

    /// The index of the main image for the cap
    var mainImage: Int

    /// The version of the first classifier capable of recognizing the cap
    var classifierVersion: Int?

    var color: Color?

    /// The subpath to the main image on the server
    var mainImagePath: String {
        String(format: "images/%04d/%04d-%02d.jpg", id, id, mainImage)
    }

    var image: CapImage {
        .init(cap: id, version: mainImage)
    }

    /**
     Create a new cap.
     - Parameter id: The unique id of the cap
     - Parameter name: The name associated with the cap
     */
    init(id: Int, name: String, classifier: Int? = nil) {
        self.id = id
        self.name = name
        self.cleanName = name.clean
        self.imageCount = 1
        self.mainImage = 0
        self.classifierVersion = classifier
    }

    init(data: CapData) {
        self.id = data.id
        self.name = data.name
        self.cleanName = data.name.clean
        self.imageCount = data.count
        self.mainImage = data.mainImage
        self.classifierVersion = data.classifierVersion
    }
    
    var data: CapData {
        .init(id: id,
              name: name,
              count: imageCount,
              mainImage: mainImage,
              classifierVersion: classifierVersion,
              color: color)
    }

    mutating func update(with data: CapData) {
        self.name = data.name
        self.cleanName = data.name.clean
        self.imageCount = data.count
        self.mainImage = data.mainImage
        self.classifierVersion = data.classifierVersion
    }

    static func ==(lhs: Cap, rhs: CapData) -> Bool {
        lhs.id == rhs.id &&
        lhs.name == rhs.name &&
        lhs.imageCount == rhs.count &&
        lhs.mainImage == rhs.mainImage &&
        lhs.classifierVersion == rhs.classifierVersion
    }

    static func !=(lhs: Cap, rhs: CapData) -> Bool {
        !(lhs == rhs)
    }

    func classifiable(by classifierVersion: Int?) -> Bool {
        guard let version = classifierVersion else {
            return false
        }
        guard let own = self.classifierVersion else {
            return false
        }
        return version >= own
    }
}

extension Cap {

    struct Color: Codable, Equatable {

        let r: Int

        let g: Int

        let b: Int
    }
}

// MARK: Protocol Identifiable

extension Cap: Identifiable {

}

// MARK: Protocol Comparable

extension Cap: Codable {

    enum CodingKeys: String, CodingKey {
        case id = "u"
        case name = "n"
        case cleanName = "c"
        case imageCount = "i"
        case mainImage = "m"
        case classifierVersion = "v"
        case color = "f"
    }
}

// MARK: Protocol Comparable

extension Cap: Comparable {

    static func < (lhs: Cap, rhs: Cap) -> Bool {
        lhs.id < rhs.id
    }
}

// MARK: Protocol Equatable

extension Cap: Equatable {

    static func == (lhs: Cap, rhs: Cap) -> Bool {
        return lhs.id == rhs.id
    }
}

// MARK: Protocol Hashable

extension Cap: Hashable {

    func hash(into hasher: inout Hasher) {
        hasher.combine(id)
    }
}

// MARK: String extension

private extension String {

    var clean: String {
        return lowercased().replacingOccurrences(of: "[^a-z0-9 ]", with: "", options: .regularExpression)
    }
}

// MARK: Int extension

private extension Int {

    var isEven: Bool {
        return self % 2 == 0
    }
}