import SwiftUI

@Observable
class TransferInfo: Identifiable, Equatable, Hashable {
  var id: UUID = UUID()
  
  var referenceNumber: UInt32
  var title: String
  var size: UInt
  
  // Status
  var completed: Bool = false
  var failed: Bool = false
  var cancelled: Bool = false
  var done: Bool {
    self.completed || self.failed || self.cancelled
  }
  
  var progress: Double = 0.0
  var speed: Double? = nil
  var timeRemaining: TimeInterval? = nil
  
  var isUpload: Bool = false
  var isDownload: Bool {
    get { !self.isUpload }
    set { self.isUpload = !newValue }
  }
  
  // Folder transfers
  var isFolder: Bool = false
  var folderName: String? = nil
  var fileName: String? = nil

  // Server association - tracks which HotlineState this transfer belongs to
  var serverID: UUID
  var serverName: String?

  // For file based transfers
  var fileURL: URL? = nil

  var progressCallback: ((TransferInfo) -> Void)? = nil
  var downloadCallback: ((TransferInfo) -> Void)? = nil
  var uploadCallback: ((TransferInfo) -> Void)? = nil
  var previewCallback: ((TransferInfo, Data) -> Void)? = nil

  init(reference: UInt32, title: String, size: UInt, serverID: UUID, serverName: String? = nil) {
    self.referenceNumber = reference
    self.title = title
    self.size = size
    self.serverID = serverID
    self.serverName = serverName
  }

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

  func hash(into hasher: inout Hasher) {
    hasher.combine(self.id)
  }
  
//  var formatSize(_ bytes: UInt) -> String {
//    let formatter = ByteCountFormatter()
//    formatter.countStyle = .file
//    formatter.allowedUnits = [.useKB, .useMB, .useGB]
//    return formatter.string(fromByteCount: Int64(bytes))
//  }
  
  var displaySize: String {
    let formatter = ByteCountFormatter()
    formatter.countStyle = .file
    formatter.allowedUnits = [.useKB, .useMB, .useGB]
    return formatter.string(fromByteCount: Int64(self.size))
  }
  
  var displaySpeed: String? {
    guard let speed = self.speed else {
      return nil
    }
    
    let formatter = ByteCountFormatter()
    formatter.countStyle = .file
    formatter.allowedUnits = [.useKB, .useMB, .useGB]
    return "\(formatter.string(fromByteCount: Int64(speed)))/s"
  }
  
  var displayTimeRemaining: String? {
    guard let timeRemaining = self.timeRemaining else {
      return nil
    }
    
    if timeRemaining < 60 {
      return "\(Int(timeRemaining))s"
    } else if timeRemaining < 3600 {
      let minutes = Int(timeRemaining / 60)
      let secs = Int(timeRemaining.truncatingRemainder(dividingBy: 60))
      return "\(minutes)m \(secs)s"
    } else {
      let hours = Int(timeRemaining / 3600)
      let minutes = Int((timeRemaining.truncatingRemainder(dividingBy: 3600)) / 60)
      return "\(hours)h \(minutes)m"
    }
  }
}