IceCubesApp/IceCubesAppWidgetsExtension/HashtagPostsWidget/HashtagPostsWidget.swift

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

struct HashtagPostsWidgetProvider: AppIntentTimelineProvider {
  func placeholder(in context: Context) -> PostsWidgetEntry {
    .init(date: Date(),
          timeline: .hashtag(tag: "Mastodon", accountId: nil),
          statuses: [.placeholder()],
          images: [:])
  }
  
  func snapshot(for configuration: HashtagPostsWidgetConfiguration, in context: Context) async -> PostsWidgetEntry {
    if let entry = await timeline(for: configuration, context: context).entries.first {
      return entry
    }
    return .init(date: Date(),
                 timeline: .hashtag(tag: "Mastodon", accountId: nil),
                 statuses: [],
                 images: [:])
  }
  
  func timeline(for configuration: HashtagPostsWidgetConfiguration, in context: Context) async -> Timeline<PostsWidgetEntry> {
    await timeline(for: configuration, context: context)
  }
  
  private func timeline(for configuration: HashtagPostsWidgetConfiguration, context: Context) async -> Timeline<PostsWidgetEntry> {
    guard let account = configuration.account, let hashgtag = configuration.hashgtag else {
      return Timeline(entries: [.init(date: Date(),
                                      timeline: .hashtag(tag: "Mastodon", accountId: nil),
                                      statuses: [],
                                      images: [:])],
               policy: .atEnd)
    }
    do {
      let statuses = await loadStatuses(for: .hashtag(tag: hashgtag, accountId: nil),
                                        account: account,
                                        widgetFamily: context.family)
      let images = try await loadImages(urls: statuses.map{ $0.account.avatar } )
      return Timeline(entries: [.init(date: Date(),
                                        timeline: .hashtag(tag: hashgtag, accountId: nil),
                                        statuses: statuses,
                                        images: images)], policy: .atEnd)
    } catch {
      return Timeline(entries: [.init(date: Date(),
                                      timeline: .hashtag(tag: "Mastodon", accountId: nil),
                                      statuses: [],
                                      images: [:])],
               policy: .atEnd)
    }
  }
}

struct HashtagPostsWidget: Widget {
  let kind: String = "HashtagPostsWidget"
  
  var body: some WidgetConfiguration {
    AppIntentConfiguration(kind: kind,
                           intent: HashtagPostsWidgetConfiguration.self,
                           provider: HashtagPostsWidgetProvider()) { entry in
      PostsWidgetView(entry: entry)
        .containerBackground(Color("WidgetBackground").gradient, for: .widget)
    }
    .configurationDisplayName("Hashtag timeline")
    .description("Show the latest post for the selected hashtag")
    .supportedFamilies([.systemSmall, .systemMedium, .systemLarge, .systemExtraLarge])
  }
}


#Preview(as: .systemMedium) {
  HashtagPostsWidget()
} timeline: {
  PostsWidgetEntry(date: .now,
                        timeline: .hashtag(tag: "Matodon", accountId: nil),
                        statuses: [.placeholder(), .placeholder(), .placeholder(), .placeholder()],
                        images: [:])
}