import DesignSystem
import Models
import Network
import SwiftUI
import Timeline
import WidgetKit

struct MentionsWidgetProvider: AppIntentTimelineProvider {
  func placeholder(in _: Context) -> PostsWidgetEntry {
    .init(date: Date(),
          title: "Mentions",
          statuses: [.placeholder()],
          images: [:])
  }

  func snapshot(for configuration: MentionsWidgetConfiguration, in context: Context) async -> PostsWidgetEntry {
    if let entry = await timeline(for: configuration, context: context).entries.first {
      return entry
    }
    return .init(date: Date(),
                 title: "Mentions",
                 statuses: [],
                 images: [:])
  }

  func timeline(for configuration: MentionsWidgetConfiguration, in context: Context) async -> Timeline<PostsWidgetEntry> {
    await timeline(for: configuration, context: context)
  }

  private func timeline(for configuration: MentionsWidgetConfiguration, context _: Context) async -> Timeline<PostsWidgetEntry> {
    do {
      guard let account = configuration.account else {
        return Timeline(entries: [.init(date: Date(),
                                        title: "Mentions",
                                        statuses: [],
                                        images: [:])],
                        policy: .atEnd)
      }
      let client = Client(server: account.account.server,
                          oauthToken: account.account.oauthToken)
      var excludedTypes = Models.Notification.NotificationType.allCases
      excludedTypes.removeAll(where: { $0 == .mention })
      let notifications: [Models.Notification] =
        try await client.get(endpoint: Notifications.notifications(minId: nil,
                                                                   maxId: nil,
                                                                   types: excludedTypes.map(\.rawValue),
                                                                   limit: 5))
      let statuses = notifications.compactMap { $0.status }
      let images = try await loadImages(urls: statuses.map { $0.account.avatar })
      return Timeline(entries: [.init(date: Date(),
                                      title: "Mentions",
                                      statuses: statuses,
                                      images: images)], policy: .atEnd)
    } catch {
      return Timeline(entries: [.init(date: Date(),
                                      title: "Mentions",
                                      statuses: [],
                                      images: [:])],
                      policy: .atEnd)
    }
  }
}

struct MentionsWidget: Widget {
  let kind: String = "MentionsWidget"

  var body: some WidgetConfiguration {
    AppIntentConfiguration(kind: kind,
                           intent: MentionsWidgetConfiguration.self,
                           provider: MentionsWidgetProvider())
    { entry in
      PostsWidgetView(entry: entry)
        .containerBackground(Color("WidgetBackground").gradient, for: .widget)
    }
    .configurationDisplayName("Mentions")
    .description("Show the latest mentions for the selected account.")
    .supportedFamilies([.systemLarge, .systemExtraLarge])
  }
}

#Preview(as: .systemMedium) {
  MentionsWidget()
} timeline: {
  PostsWidgetEntry(date: .now,
                   title: "Mentions",
                   statuses: [.placeholder(), .placeholder(), .placeholder(), .placeholder()],
                   images: [:])
}