/*
 * Keyman is copyright (C) SIL Global. MIT License.
 *
 * Created by Shawn Schantz on 2026-06-01
 *
 * Class for tracking overall state of the installation.
 * Includes functions for mapping to a Dictionary to store in the UserDefaults.
 */

import Foundation
import KeymanSettings

public class InstallationState {
  // keys to the fields we are storing in the UserDefaults KMInstallationState dictionary
  let kVersionKey = "version"
  let kDateRestartRequestedKey = "dateRestartRequested"
  let kRepairKey = "isRepair"
  let kDisplayedInstallComplete = "displayedInstallComplete"

  public let keymanVersion: String
  public var dateRestartRequested: Date?
  // indicates whether we are repairing a previous installation or doing a full installation
  public let isRepair: Bool
  // indicates whether the installation complete message has been displayed to the user
  public var hasDisplayedInstallComplete: Bool
  // this list of tasks that make up this installation
  public var tasks: Set<InstallationTask>
  
  /**
   * The installation is complete if all its tasks are complete.
   * Returns true if the tasks list is empty, but it should never be empty.
   */
  public var isComplete: Bool {
    return tasks.allSatisfy(\.isComplete)
  }

  /**
   * The installation is new if this is not a repair and no tasks are complete.
   * Returns true if the tasks list is empty, but it should never be empty.
   */
  public var isNew: Bool {
    return !isRepair && tasks.allSatisfy{ !$0.isComplete }
  }

  /**
   * The installation has at least one task complete and at least one remaining to complete.
   * It does not matter if this is a repair or not.
   */
  public var isInProgress: Bool {
    return tasks.contains(where: { !$0.isComplete }) && tasks.contains(where: { $0.isComplete})
  }

  init(version: String, dateRestartRequested: Date? = nil, isRepair: Bool = false, hasDisplayedInstallComplete: Bool = false, tasks: Set<InstallationTask>) {
    self.keymanVersion = version
    self.dateRestartRequested = dateRestartRequested
    self.isRepair = isRepair
    self.hasDisplayedInstallComplete = hasDisplayedInstallComplete
    self.tasks = tasks
  }
  
  /**
   * create a new InstallationState with an existing InstallationState and a task to mark as completed
   */
  public static func createCopyWithCompletedTask (from state: InstallationState, with completedTask: InstallationTaskType) -> InstallationState {
    var newTaskList = state.tasks
    let completedTask = InstallationTask(task: completedTask, completed: true)
    newTaskList.update(with: completedTask)
    
    return InstallationState(version: state.keymanVersion, dateRestartRequested: state.dateRestartRequested, isRepair: state.isRepair, hasDisplayedInstallComplete: state.hasDisplayedInstallComplete, tasks: newTaskList)
  }
  
  /**
   * create a new InstallationState with an existing InstallationState and a task to mark as completed
   */
  public static func createCopy (from state: InstallationState) -> InstallationState {
    let newTaskList = state.tasks
    
    return InstallationState(version: state.keymanVersion, dateRestartRequested: state.dateRestartRequested, isRepair: state.isRepair, hasDisplayedInstallComplete: state.hasDisplayedInstallComplete, tasks: newTaskList)
  }

  /**
   * initialize using the dictionary from UserDefaults
   */
  init?(from dictionary: Dictionary<String, Any>) {
    self.keymanVersion = dictionary[kVersionKey] as? String ?? ""
    self.dateRestartRequested = dictionary[kDateRestartRequestedKey] as? Date
    self.isRepair = dictionary[kRepairKey] as? Bool ?? false
    self.hasDisplayedInstallComplete = dictionary[kDisplayedInstallComplete] as? Bool ?? false
    var installationTasks = Set<InstallationTask>()
    
    // for every task flag found in dictionary, insert a task in the tasks array
    if let taskFlag = dictionary[InstallationTaskType.prepareNewInstall.rawValue] as? Bool {
      installationTasks.insert(InstallationTask(task: .prepareNewInstall, completed: taskFlag))
    }
    if let taskFlag = dictionary[InstallationTaskType.prepareNewRepair.rawValue] as? Bool {
      installationTasks.insert(InstallationTask(task: .prepareNewRepair, completed: taskFlag))
    }
    if let taskFlag = dictionary[InstallationTaskType.enableInputMethod.rawValue] as? Bool {
      installationTasks.insert(InstallationTask(task: .enableInputMethod, completed: taskFlag))
    }
    if let taskFlag = dictionary[InstallationTaskType.requestAccess.rawValue] as? Bool {
      installationTasks.insert(InstallationTask(task: .requestAccess, completed: taskFlag))
    }
    if let taskFlag = dictionary[InstallationTaskType.confirmAccess.rawValue] as? Bool {
      installationTasks.insert(InstallationTask(task: .confirmAccess, completed: taskFlag))
    }
    if let taskFlag = dictionary[InstallationTaskType.requestRestart.rawValue] as? Bool {
      installationTasks.insert(InstallationTask(task: .requestRestart, completed: taskFlag))
    }
    if let taskFlag = dictionary[InstallationTaskType.confirmRestart.rawValue] as? Bool {
      installationTasks.insert(InstallationTask(task: .confirmRestart, completed: taskFlag))
    }

    self.tasks = installationTasks
  }
  
  /**
   * create a dictionary for storing the current InstallationState state in the UserDefaults
   */
  public func toUserDefaultsDictionary() -> Dictionary<String, Any> {
    var dictionary: Dictionary<String, Any> = [:]
    
    dictionary[kVersionKey] = keymanVersion
    if let dateRestartRequested = self.dateRestartRequested {
      dictionary[kDateRestartRequestedKey] = dateRestartRequested
    }
    dictionary[kRepairKey] = self.isRepair
    dictionary[kDisplayedInstallComplete] = self.hasDisplayedInstallComplete

    for task in self.tasks {
      dictionary[task.taskType.rawValue] = task.isComplete
    }
    
    return dictionary
  }
}