Flaro/Flixy/Views/Settings/HomeLayoutView.swift

import SwiftUI
import FlixyDesign
import MediaKit

/// Reihen der Startseite ein- und ausblenden und umsortieren.
struct HomeLayoutView: View {
    @Environment(FlixySession.self) private var session
    @Environment(\.flixyAccent) private var accent
    @Environment(HomeLayoutSettings.self) private var layout

    @State private var rows: [HomeRow] = []
    @State private var isLoading = true

    var body: some View {
        list
        .background(Color.flixyCanvas)
        .navigationTitle(Text("homeLayout.title"))
        .navigationBarTitleDisplayMode(.inline)
        .toolbar { EditButton() }
        .task { await load() }
    }

    private var list: some View {
        List {
            @Bindable var layout = layout

            Section {
                Picker("home.heroSource", selection: $layout.heroSource) {
                    ForEach(HomeLayoutSettings.HeroSource.allCases) { source in
                        Text(source.label).tag(source)
                    }
                }
                Picker("home.heroCount", selection: $layout.heroCount) {
                    ForEach(HomeLayoutSettings.heroCountChoices, id: \.self) { count in
                        Text(count.formatted()).tag(count)
                    }
                }
            } header: {
                Text("home.hero")
            } footer: {
                Text("home.heroExplanation")
            }
            .listRowBackground(Color.flixySurface)

            Section {
                Toggle("home.combineContinue", isOn: $layout.combinesContinueRows)
                Toggle("home.hideWatched", isOn: $layout.hidesWatchedInLatest)
            }
            .listRowBackground(Color.flixySurface)

            if isLoading {
                ProgressView()
                    .frame(maxWidth: .infinity)
                    .listRowBackground(Color.clear)
            } else if rows.isEmpty {
                Text("homeLayout.empty")
                    .foregroundStyle(Color.flixyTextSecondary)
                    .listRowBackground(Color.flixySurface)
            }

            Section {
                ForEach($rows) { $row in
                    Toggle(isOn: Binding(
                        get: { !row.isHidden },
                        set: {
                            row.isHidden = !$0
                            layout.setHidden(!$0, for: row.id)
                        }
                    )) {
                        Text(row.title)
                            .foregroundStyle(Color.flixyTextPrimary)
                    }
                    .listRowBackground(Color.flixySurface)
                }
                .onMove { indices, destination in
                    rows.move(fromOffsets: indices, toOffset: destination)
                    layout.setOrder(rows.map(\.id))
                }
            } header: {
                Text("home.rowsHeader")
            } footer: {
                Text("homeLayout.explanation")
            }
        }
        // Ausdrücklich, nicht nur geerbt.
        //
        // Listen und Formulare zeichnen ihre Zeilen teilweise in einem
        // eigenen Darstellungskontext, in dem eigene Umgebungswerte verloren
        // gehen können — sichtbar an Picker-Werten, die in der Standardfarbe
        // leuchteten, während die Schalter daneben schon die gewählte trugen.
        .tint(accent)
        .scrollContentBackground(.hidden)
    }

    private func load() async {
        defer { isLoading = false }
        guard let backend = session.backend else { return }
        // Die Reihen kommen vom Server — es gibt keine feste Liste, die sich
        // vorweg anzeigen ließe. Was hier steht, hängt davon ab, welche
        // Mediatheken und Sammlungen angelegt sind.
        let hubs = (try? await backend.homeRows()) ?? []
        rows = layout.rows(from: hubs)
    }
}

extension HomeLayoutSettings.HeroSource {
    var label: LocalizedStringKey {
        switch self {
        case .continueFirst: "home.heroSource.continueFirst"
        case .latestOnly: "home.heroSource.latestOnly"
        }
    }
}