import AppKit
import SwiftUI

struct StationDetailView: View {
    @Environment(AppModel.self) private var model
    @Environment(\.openURL) private var openURL

    var body: some View {
        Group {
            if let station = model.library.selectedStation {
                ScrollView {
                    VStack(alignment: .leading, spacing: 16) {
                        header(station)
                        actions(station)
                        if model.playback.currentStation?.id == station.id {
                            nowPlayingSection
                        }
                        technicalSection(station)
                        linksSection(station)
                    }
                    .padding(16)
                    .frame(maxWidth: .infinity, alignment: .leading)
                }
            } else {
                ContentUnavailableView("No station selected", systemImage: "radio")
            }
        }
        .background(.regularMaterial)
    }

    private func header(_ station: RadioStation) -> some View {
        let artworkImage: NSImage
        if model.playback.currentStation?.id == station.id {
            artworkImage = model.playback.currentArtwork
        } else {
            artworkImage = model.artwork.image(for: station) ?? NSImage()
        }

        return VStack(alignment: .leading, spacing: 10) {
            Image(nsImage: artworkImage)
                .resizable()
                .scaledToFill()
                .frame(width: 72, height: 72)
                .background(.quaternary)
                .clipShape(RoundedRectangle(cornerRadius: 10))

            VStack(alignment: .leading, spacing: 4) {
                Text(station.name)
                    .font(.title3.weight(.semibold))
                    .lineLimit(2)
                if !station.country.isEmpty {
                    Text(station.country)
                        .font(.subheadline)
                        .foregroundStyle(.secondary)
                }
            }
        }
    }

    private func actions(_ station: RadioStation) -> some View {
        HStack(spacing: 8) {
            Button {
                model.play(station)
            } label: {
                Label("Play", systemImage: "play.fill")
            }

            Button {
                model.library.toggleFavorite(station)
            } label: {
                Label(model.library.isFavorite(station) ? "Remove Favorite" : "Add Favorite", systemImage: model.library.isFavorite(station) ? "star.fill" : "star")
            }

            if !model.library.groups.isEmpty {
                Menu {
                    ForEach(model.library.groups) { group in
                        Button {
                            if model.library.isStationInGroup(station, group: group) {
                                model.library.removeStationFromGroup(station, group: group)
                            } else {
                                model.library.addStationToGroup(station, group: group)
                            }
                        } label: {
                            Label(
                                model.library.isStationInGroup(station, group: group) ? "Remove from \(group.name)" : "Add to \(group.name)",
                                systemImage: model.library.isStationInGroup(station, group: group) ? "checkmark" : "plus"
                            )
                        }
                    }
                } label: {
                    Label("Folders", systemImage: "folder.badge.plus")
                }
            }
        }
        .buttonStyle(.bordered)
        .controlSize(.small)
    }

    private var nowPlayingSection: some View {
        DetailSection(title: "Now Playing") {
            LabeledContent("Status", value: model.playback.state.title)
            if case let .failed(error) = model.playback.state {
                Text(error.detail)
                    .foregroundStyle(.red)
                    .font(.caption)
            }
            if !model.playback.currentTrackArtist.isEmpty {
                LabeledContent("Artist", value: model.playback.currentTrackArtist)
            }
            if !model.playback.currentTrackTitle.isEmpty {
                LabeledContent("Title", value: model.playback.currentTrackTitle)
            }
            if model.playback.currentTrackArtist.isEmpty && model.playback.currentTrackTitle.isEmpty, !model.playback.state.isPlaying, model.playback.state != .stopped {
                Text("No stream metadata yet")
                    .foregroundStyle(.secondary)
            }
        }
    }

    private func technicalSection(_ station: RadioStation) -> some View {
        DetailSection(title: "Details") {
            if !station.codec.isEmpty {
                LabeledContent("Codec", value: station.codec.uppercased())
            }
            if station.bitrate > 0 {
                LabeledContent("Bitrate", value: "\(station.bitrate) kbps")
            }
            if station.votes > 0 {
                LabeledContent("Votes", value: station.votes.formatted())
            }
            if !station.tags.isEmpty {
                LabeledContent("Tags") {
                    Text(station.tags)
                        .lineLimit(4)
                        .multilineTextAlignment(.trailing)
                }
            }
        }
    }

    private func linksSection(_ station: RadioStation) -> some View {
        DetailSection(title: "Links") {
            if let homepage = URL(string: station.homepage), !station.homepage.isEmpty {
                Button {
                    openURL(homepage)
                } label: {
                    Label("Open Homepage", systemImage: "safari")
                }
            }
            Button {
                NSPasteboard.general.clearContents()
                NSPasteboard.general.setString(station.playbackURLString, forType: .string)
            } label: {
                Label("Copy Stream URL", systemImage: "doc.on.doc")
            }
            .disabled(station.playbackURLString.isEmpty)
        }
        .buttonStyle(.bordered)
        .controlSize(.small)
    }
}

private struct DetailSection<Content: View>: View {
    let title: LocalizedStringKey
    @ViewBuilder let content: Content

    var body: some View {
        VStack(alignment: .leading, spacing: 8) {
            Text(title)
                .font(.headline)
            VStack(alignment: .leading, spacing: 6) {
                content
            }
            .font(.subheadline)
        }
    }
}