// Copyright 2022 Google LLC. All rights reserved.
//
//
// 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.

import GoogleMaps
import UIKit

final class PanoramaServiceController: UIViewController {
  private let markerLocation = CLLocationCoordinate2D.sydney

  private var mySubview = UIView(frame: .zero)
  private var statusLabel = UILabel(frame: .zero)
  private var result = UITextView(frame: .zero)

  private var panoService: GMSPanoramaService?
  private var requestCount = 0
  private var responseCount = 0

  override func loadView() {
    navigationController?.navigationBar.isTranslucent = false
    view = mySubview

    statusLabel.alpha = 1.0
    statusLabel.backgroundColor = .blue
    statusLabel.textColor = .white
    statusLabel.textAlignment = .center
    statusLabel.text = "Service Never Called"
    view.addSubview(statusLabel)
    statusLabel.translatesAutoresizingMaskIntoConstraints = false

    view.addSubview(result)
    result.translatesAutoresizingMaskIntoConstraints = false

    NSLayoutConstraint.activate([
      statusLabel.topAnchor.constraint(equalTo: view.topAnchor),
      statusLabel.heightAnchor.constraint(equalToConstant: 30),
      statusLabel.leadingAnchor.constraint(equalTo: view.leadingAnchor),
      statusLabel.trailingAnchor.constraint(equalTo: view.trailingAnchor),

      result.topAnchor.constraint(equalTo: statusLabel.bottomAnchor),
      result.bottomAnchor.constraint(equalTo: view.bottomAnchor),
      result.leadingAnchor.constraint(equalTo: view.leadingAnchor),
      result.trailingAnchor.constraint(equalTo: view.trailingAnchor),
    ])
  }

  override func viewDidAppear(_ animated: Bool) {
    if panoService == nil {
      panoService = GMSPanoramaService()
      statusLabel.text = "Service initialized \(panoService?.description ?? "nil")"
    }

    requestCount += 1
    panoService?.requestPanoramaNearCoordinate(
      markerLocation,
      radius: 300,  // meters
      source: .outside
    ) {
      pano, err in
      self.responseCount += 1
      self.statusLabel.text =
        "Callback invoked \(self.responseCount) time(s) out of \(self.requestCount) requests."

      if let pano = pano {
        self.result.text = [
          "id: \(pano.panoramaID)",
          "#neighbors: \(pano.links.count)",
          "coordinate: \(pano.coordinate)",
          "description: \(pano.description)",
          "debugDescription: \(pano.debugDescription)",
        ].joined(separator: "\n")
      } else {
        self.result.text = "<nil>"
      }
    }
    super.viewWillAppear(animated)
  }
}