//
//  AnnouncementListRow.swift
//  Tusker
//
//  Created by Shadowfacts on 4/17/24.
//  Copyright © 2024 Shadowfacts. All rights reserved.
//

import SwiftUI
import Pachyderm
import TuskerComponents
import WebURLFoundationExtras

struct AnnouncementListRow: View {
    @Binding var announcement: Announcement
    let mastodonController: MastodonController
    let navigationDelegate: TuskerNavigationDelegate?
    let removeAnnouncement: @MainActor () -> Void
    @State private var contentTextViewHeight: CGFloat?
    @State private var isShowingAddReactionSheet = false
    
    var body: some View {
        if #available(iOS 16.0, *) {
            mostOfTheBody
                .alignmentGuide(.listRowSeparatorLeading, computeValue: { dimension in
                    dimension[.leading]
                })
        } else {
            mostOfTheBody
        }
    }
    
    private var mostOfTheBody: some View {
        VStack {
            HStack(alignment: .top) {
                AnnouncementContentTextViewRepresentable(announcement: announcement, navigationDelegate: navigationDelegate) { newHeight in
                    DispatchQueue.main.async {
                        contentTextViewHeight = newHeight
                    }
                }
                .frame(height: contentTextViewHeight)
                
                Text(announcement.publishedAt, format: .abbreviatedTimeAgo)
                    .fontWeight(.light)
                    .foregroundStyle(.secondary)
            }
            .padding(.horizontal, 16)

            ScrollView(.horizontal) {
                LazyHStack {
                    Button {
                        isShowingAddReactionSheet = true
                    } label: {
                        Label {
                            Text("Add Reaction")
                        } icon: {
                            if #available(iOS 16.0, *) {
                                Image("face.smiling.badge.plus")
                            } else {
                                Image(systemName: "face.smiling")
                            }
                        }
                    }
                    .labelStyle(.iconOnly)
                    .padding(4)
                    .hoverEffect()
                    
                    ForEach($announcement.reactions, id: \.name) { $reaction in
                        ReactionButton(announcement: announcement, reaction: $reaction, mastodonController: mastodonController)
                    }
                }
                .frame(height: 32)
                .padding(.horizontal, 16)
            }
        }
        .padding(.vertical, 8)
        .listRowInsets(EdgeInsets(top: 0, leading: 0, bottom: 0, trailing: 0))
        .swipeActions {
            Button(role: .destructive) {
                Task {
                    await dismissAnnouncement()
                }
            } label: {
                Text("Dismiss")
            }
        }
        .contextMenu {
            Button(role: .destructive) {
                Task {
                    await dismissAnnouncement()
                    await removeAnnouncement()
                }
            } label: {
                Label("Dismiss", systemImage: "xmark")
            }
        }
        .sheet(isPresented: $isShowingAddReactionSheet) {
            AddReactionView(mastodonController: mastodonController, addReaction: self.addReaction)
        }
    }
    
    private func dismissAnnouncement() async {
        do {
            _ = try await mastodonController.run(Announcement.dismiss(id: announcement.id))
        } catch {
            Logging.general.error("Error dismissing attachment: \(String(describing: error))")
        }
    }
    
    @MainActor
    private func addReaction(_ reaction: AddReactionView.Reaction) async throws {
        let name = switch reaction {
        case .emoji(let s): s
        case .custom(let emoji): emoji.shortcode
        }
        _ = try await mastodonController.run(Announcement.react(id: announcement.id, name: name))
        for (idx, reaction) in announcement.reactions.enumerated() {
            if reaction.name == name {
                announcement.reactions[idx].me = true
                announcement.reactions[idx].count += 1
                return
            }
        }
        let url: URL?
        let staticURL: URL?
        if case .custom(let emoji) = reaction {
            url = URL(emoji.url)
            staticURL = URL(emoji.staticURL)
        } else {
            url = nil
            staticURL = nil
        }
        announcement.reactions.append(.init(name: name, count: 1, me: true, url: url, staticURL: staticURL))
    }
}

private struct AnnouncementContentTextViewRepresentable: UIViewRepresentable {
    let announcement: Announcement
    let navigationDelegate: TuskerNavigationDelegate?
    let heightChanged: (CGFloat) -> Void
    
    func makeUIView(context: Context) -> AnnouncementContentTextView {
        let view = AnnouncementContentTextView()
        view.isScrollEnabled = true
        view.backgroundColor = .clear
        view.isEditable = false
        view.isSelectable = false
        view.setContentCompressionResistancePriority(.defaultLow, for: .horizontal)
        view.adjustsFontForContentSizeCategory = true
        return view
    }
    
    func updateUIView(_ uiView: AnnouncementContentTextView, context: Context) {
        uiView.navigationDelegate = navigationDelegate
        uiView.setTextFrom(announcement: announcement, content: TimelineStatusCollectionViewCell.htmlConverter.convert(announcement.content))
        uiView.heightChanged = heightChanged
    }
}

private struct ReactionButton: View {
    let announcement: Announcement
    @Binding var reaction: Announcement.Reaction
    let mastodonController: MastodonController
    @State private var customEmojiImage: (Image, CGFloat)?
    
    var body: some View {
        Button(action: self.toggleReaction) {
            let countStr = reaction.count.formatted(.number)
            let title = if reaction.name.count == 1 {
                "\(reaction.name) \(countStr)"
            } else {
                countStr
            }
            if reaction.url != nil {
                Label {
                    Text(title)
                } icon: {
                    if let (image, aspectRatio) = customEmojiImage {
                        image.aspectRatio(aspectRatio, contentMode: .fit)
                    }
                }
            } else {
                Text(title)
            }
        }
        .buttonStyle(TintedButtonStyle(highlighted: reaction.me == true))
        .font(.body.monospacedDigit())
        .hoverEffect()
        .task {
            if let url = reaction.url,
               let image = await ImageCache.emojis.get(url).1 {
                let aspectRatio = image.size.width / image.size.height
                customEmojiImage = (
                    Image(uiImage: image).resizable(),
                    aspectRatio
                )
            }
        }
    }
    
    private func toggleReaction() {
        if reaction.me == true {
            let oldCount = reaction.count
            reaction.me = false
            reaction.count -= 1
            Task {
                do {
                    _ = try await mastodonController.run(Announcement.unreact(id: announcement.id, name: reaction.name))
                } catch {
                    reaction.me = true
                    reaction.count = oldCount
                }
            }
        } else {
            let oldCount = reaction.count
            reaction.me = true
            reaction.count += 1
            Task {
                do {
                    _ = try await mastodonController.run(Announcement.react(id: announcement.id, name: reaction.name))
                } catch {
                    reaction.me = false
                    reaction.count = oldCount
                }
            }
        }
    }
}

private struct TintedButtonStyle: ButtonStyle {
    let highlighted: Bool
    
    func makeBody(configuration: Configuration) -> some View {
        configuration.label
            .foregroundStyle(highlighted ? AnyShapeStyle(.white) : AnyShapeStyle(.tint))
            .padding(.vertical, 4)
            .padding(.horizontal, 8)
            .frame(height: 32)
            .background(.tint.opacity(highlighted ? 1 : 0.2), in: RoundedRectangle(cornerRadius: 4))
            .opacity(configuration.isPressed ? 0.8 : 1)
    }
}

//#Preview {
//    AnnouncementListRow()
//}