// Copyright 2020 Google LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//      http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

#if canImport(Combine) && swift(>=5.0)

  #if os(iOS)

    import Foundation

    import Combine
    import FirebaseAuth

    @available(swift 5.0)
    @available(iOS 13.0, *)
    @available(macOS, unavailable)
    @available(macCatalyst, unavailable)
    @available(tvOS, unavailable)
    @available(watchOS, unavailable)
    public extension PhoneAuthProvider {
      /// Starts the phone number authentication flow by sending a verification code to the
      /// specified phone number.
      ///
      /// The publisher will emit events on the **main** thread.
      ///
      /// - Parameters:
      ///     - phoneNumber: The phone number to be verified.
      ///     - uiDelegate: An object used to present the `SFSafariViewController`. The object is retained
      ///       by this method until the completion block is executed.
      ///
      /// - Returns: A publisher that emits an `VerificationID` when the verification flow completed
      ///   successfully, or an error otherwise. The publisher will emit on the *main* thread.
      ///
      /// - Remark:
      ///   Possible error codes:
      ///
      ///   - `FIRAuthErrorCodeCaptchaCheckFailed` - Indicates that the reCAPTCHA token obtained by
      ///      the Firebase Auth is invalid or has expired.
      ///   - `FIRAuthErrorCodeQuotaExceeded` - Indicates that the phone verification quota for this
      ///      project has been exceeded.
      ///   - `FIRAuthErrorCodeInvalidPhoneNumber` - Indicates that the phone number provided is
      ///      invalid.
      ///   - `FIRAuthErrorCodeMissingPhoneNumber` - Indicates that a phone number was not provided.
      @discardableResult
      func verifyPhoneNumber(_ phoneNumber: String,
                             uiDelegate: AuthUIDelegate? = nil)
        -> Future<String, Error> {
        Future<String, Error> { promise in
          self.verifyPhoneNumber(phoneNumber, uiDelegate: uiDelegate) { verificationID, error in
            if let error = error {
              promise(.failure(error))
            } else if let verificationID = verificationID {
              promise(.success(verificationID))
            }
          }
        }
      }

      /// Verify ownership of the second factor phone number by the current user.
      ///
      /// The publisher will emit events on the **main** thread.
      ///
      /// - Parameters:
      ///     - phoneNumber: The phone number to be verified.
      ///     - uiDelegate: An object used to present the `SFSafariViewController`. The object is retained
      ///       by this method until the completion block is executed.
      ///     - session: A session to identify the MFA flow. For enrollment, this identifies the user
      ///       trying to enroll. For sign-in, this identifies that the user already passed the first
      ///       factor challenge.
      ///
      /// - Returns: A publisher that emits an `VerificationID` when the verification flow completed
      ///   successfully, or an error otherwise. The publisher will emit on the *main* thread.
      ///
      /// - Remark:
      ///   Possible error codes:
      ///
      ///   - `FIRAuthErrorCodeCaptchaCheckFailed` - Indicates that the reCAPTCHA token obtained by
      ///      the Firebase Auth is invalid or has expired.
      ///   - `FIRAuthErrorCodeQuotaExceeded` - Indicates that the phone verification quota for this
      ///      project has been exceeded.
      ///   - `FIRAuthErrorCodeInvalidPhoneNumber` - Indicates that the phone number provided is
      ///      invalid.
      ///   - `FIRAuthErrorCodeMissingPhoneNumber` - Indicates that a phone number was not provided.
      @discardableResult
      func verifyPhoneNumber(_ phoneNumber: String,
                             uiDelegate: AuthUIDelegate? = nil,
                             multiFactorSession: MultiFactorSession?)
        -> Future<String, Error> {
        Future<String, Error> { promise in
          self.verifyPhoneNumber(
            phoneNumber,
            uiDelegate: uiDelegate,
            multiFactorSession: multiFactorSession
          ) { verificationID, error in
            if let error = error {
              promise(.failure(error))
            } else if let verificationID = verificationID {
              promise(.success(verificationID))
            }
          }
        }
      }

      /// Verify ownership of the second factor phone number by the current user.
      ///
      /// The publisher will emit events on the **main** thread.
      ///
      /// - Parameters:
      ///   - phoneNumber: The phone number to be verified.
      ///   - UIDelegate: An object used to present the SFSafariViewController. The object is retained
      ///   by this method until the completion block is executed.
      ///   - multiFactorSession: session A session to identify the MFA flow. For enrollment, this identifies the user
      ///   trying to enroll. For sign-in, this identifies that the user already passed the first factor challenge.
      /// - Returns: A publisher that emits an `VerificationID` when the verification flow completed
      ///   successfully, or an error otherwise. The publisher will emit on the *main* thread.
      @discardableResult
      func verifyPhoneNumber(with phoneMultiFactorInfo: PhoneMultiFactorInfo,
                             uiDelegate: AuthUIDelegate? = nil,
                             multiFactorSession: MultiFactorSession?)
        -> Future<String, Error> {
        Future<String, Error> { promise in
          self.verifyPhoneNumber(with: phoneMultiFactorInfo,
                                 uiDelegate: uiDelegate,
                                 multiFactorSession: multiFactorSession) { verificationID, error in
            if let error = error {
              promise(.failure(error))
            } else if let verificationID = verificationID {
              promise(.success(verificationID))
            }
          }
        }
      }
    }

  #endif // os(iOS)

#endif // canImport(Combine) && swift(>=5.0)
