//
//  InitialView.swift
//  MattermostShare
//
// Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved.
// See LICENSE.txt for license information.
//

import SwiftUI

struct InitialView: View {
  @EnvironmentObject var shareViewModel: ShareViewModel
  
  @Binding var attachments: [AttachmentModel]
  @Binding var linkPreviewUrl: String
  @Binding var message: String
  @State var error: String?
  
  let onError = NotificationCenter.default.publisher(for: Notification.Name("errorPosting"))
  
  var noServers: Bool {
    shareViewModel.allServers.count == 0 || shareViewModel.server == nil
  }
  
  var noChannels: Bool {
    shareViewModel.allServers.allSatisfy({!$0.hasChannels})
  }
  
  init(attachments: Binding<[AttachmentModel]>,
       linkPreviewUrl: Binding<String>,
       message: Binding<String>
  ) {
    let appearance = UINavigationBarAppearance()
    appearance.configureWithTransparentBackground()
    
    appearance.titleTextAttributes = [.foregroundColor: UIColor(.white), .font: UIFont(name: "Metropolis-SemiBold", size: 18) as Any]
    appearance.backgroundColor = UIColor(Color.theme.sidebarBg)
    UINavigationBar.appearance().standardAppearance = appearance
    UINavigationBar.appearance().scrollEdgeAppearance = appearance
    UINavigationBar.appearance().tintColor = UIColor(Color.theme.sidebarText)
    self._attachments = attachments
    self._linkPreviewUrl = linkPreviewUrl
    self._message = message
  }
  
  var body: some View {
    return VStack {
      if error != nil {
        ErrorSharingView(error: error!)
          .transition(.opacity)
      } else if noServers {
        NoServersView()
      } else if noChannels {
        NoMembershipView()
      } else {
        ContentView(
          attachments: $attachments,
          linkPreviewUrl: $linkPreviewUrl,
          message: $message
        )
      }
    }
    .accentColor(.white)
    .navigationBarTitle(
      NSLocalizedString("share_extension.share_screen.title",
        value: "Share to {applicationName}",
        comment: ""
      )
      .replacingOccurrences(
        of: "{applicationName}",
        with: Bundle.main.infoDictionary?["CFBundleDisplayName"] as? String ?? "Mattermost Beta"
      ),
      displayMode: .inline
    )
    .navigationBarItems(
      leading: CancelButton(attachments: attachments),
      trailing: PostButton(
        attachments: $attachments,
        linkPreviewUrl: linkPreviewUrl,
        message: $message
      )
    )
    .padding(20)
    .animation(.linear(duration: 0.3))
    .onReceive(onError) {obj in
      if let userInfo = obj.userInfo, let info = userInfo["info"] as? String {
        error = info
      }
    }
  }
}