import Foundation
import SwiftUI

enum ClientState {
    
    /// The initial state after app launch
    case initial
    
    /// There are no keys stored locally on the client. New keys must be generated before use.
    case noKeysAvailable
    
    /// New keys have been generated and can now be transmitted to the device.
    case newKeysGenerated
    
    /// The device status could not be determined
    case statusRequestFailed
    
    /// The status received from the server could not be decoded
    case unknownDeviceStatus
    
    /// The remote device is not connected (no socket opened)
    case deviceDisconnected
    
    /// The device is connected and ready to receive a key
    case deviceConnected
    
    /// The key is being transmitted and a response is awaited
    case waitingForResponse
    
    /// The transmitted key was rejected (multiple possible reasons)
    case keyRejected
    
    /// Internal errors with the implementation
    case internalError
    
    /// The configuration of the devices doesn't match
    case configurationError

    /// The device responded that the opening action was started
    case openSesame
    
    /// All keys have been used
    case allKeysUsed
    
    var canSendKey: Bool {
        switch self {
        case .deviceConnected, .openSesame, .keyRejected:
            return true
        default:
            return false
        }
    }
    
    init(keyResult: KeyResult) {
        switch keyResult {
        case .textReceived, .unexpectedSocketEvent, .unknownDeviceError:
            self = .unknownDeviceStatus
        case .invalidPayloadSize, .invalidKeyIndex, .invalidKey:
            self = .configurationError
        case .keyAlreadyUsed, .keyWasSkipped:
            self = .keyRejected
        case .keyAccepted:
            self = .openSesame
        case .noBodyData, .corruptkeyData:
            self = .internalError
        case .deviceNotConnected, .deviceTimedOut:
            self = .deviceDisconnected
        }
    }
    
    var description: String {
        switch self {
        case .initial:
            return "Checking state..."
        case .noKeysAvailable:
            return "No keys found"
        case .newKeysGenerated:
            return "New keys generated"
        case .deviceDisconnected:
            return "Device not connected"
        case .statusRequestFailed:
            return "Unable to get device status"
        case .unknownDeviceStatus:
            return "Unknown device status"
        case .deviceConnected:
            return "Device connected"
        case .waitingForResponse:
            return "Waiting for response"
        case .internalError:
            return "An internal error occured"
        case .configurationError:
            return "Configuration error"
    
        case .allKeysUsed:
            return "No fresh keys available"
        case .keyRejected:
            return "The key was rejected"
        case .openSesame:
            return "Unlocked"
        }
    }
    
    var openButtonText: String {
        switch self {
        case .initial, .statusRequestFailed, .unknownDeviceStatus, .deviceDisconnected, .newKeysGenerated, .configurationError, .internalError:
            return "Connect"
        case .allKeysUsed, .noKeysAvailable:
            return "Disabled"
        case .deviceConnected, .keyRejected, .openSesame:
            return "Unlock"
        case .waitingForResponse:
            return "Unlocking..."
        }
    }
    
    var openButtonColor: Color {
        switch self {
        case .initial, .newKeysGenerated, .statusRequestFailed, .waitingForResponse:
            return .yellow
        case .noKeysAvailable, .allKeysUsed, .deviceDisconnected, .unknownDeviceStatus, .keyRejected, .configurationError, .internalError:
            return .red
        case .deviceConnected, .openSesame:
            return .green
        }
    }
    
    var openActionIsEnabled: Bool {
        switch self {
        case .allKeysUsed, .noKeysAvailable, .waitingForResponse:
            return false
        default:
            return true
        }
    }
    
    
}