vorleser/Vorleser/ContentView.swift

import SwiftUI

struct ContentView: View {
    @StateObject private var viewModel = LibraryViewModel()
    @State private var selectedItem: BookItem?

    var body: some View {
        NavigationStack {
            VStack(alignment: .leading, spacing: 16) {
                header

                if viewModel.items.isEmpty {
                    emptyState
                } else {
                    bookList
                }

                Spacer()
            }
            .padding(20)
            .navigationTitle("Vorleser")
            .toolbar {
                ToolbarItem(placement: .topBarTrailing) {
                    Button("Import EPUB") {
                        viewModel.isImporting = true
                    }
                }
            }
            .sheet(isPresented: $viewModel.isImporting) {
                DocumentPicker(onPick: { url in
                    viewModel.isImporting = false
                    viewModel.importPicked(url: url)
                }, onCancel: {
                    viewModel.isImporting = false
                })
            }
            .alert("Import failed", isPresented: .constant(viewModel.lastErrorMessage != nil), actions: {
                Button("OK", role: .cancel) {
                    viewModel.lastErrorMessage = nil
                }
            }, message: {
                Text(viewModel.lastErrorMessage ?? "")
            })
        }
    }

    private var header: some View {
        VStack(alignment: .leading, spacing: 8) {
            Text("Local EPUB reader")
                .font(.title2.weight(.semibold))
            Text("On-device, high-quality narration powered by CoreML.")
                .foregroundStyle(.secondary)
        }
    }

    private var emptyState: some View {
        VStack(alignment: .leading, spacing: 12) {
            Text("No books yet")
                .font(.headline)
            Text("Import an EPUB from Files or iCloud to start preparing narration.")
                .foregroundStyle(.secondary)
            Button("Import EPUB") {
                viewModel.isImporting = true
            }
            .buttonStyle(.borderedProminent)
        }
        .frame(maxWidth: .infinity, alignment: .leading)
        .padding(16)
        .background(.thinMaterial)
        .clipShape(RoundedRectangle(cornerRadius: 16, style: .continuous))
    }

    private var bookList: some View {
        List(viewModel.items) { item in
            NavigationLink(value: item) {
                VStack(alignment: .leading, spacing: 4) {
                    Text(item.title)
                        .font(.headline)
                    Text(item.sourceURL.lastPathComponent)
                        .font(.caption)
                        .foregroundStyle(.secondary)
                }
            }
        }
        .listStyle(.plain)
        .navigationDestination(for: BookItem.self) { item in
            ReaderView(item: item)
        }
    }
}

#Preview {
    ContentView()
}