import SwiftUI
import UIKit

/// Diagnostic log viewer. Shows the in-memory/persisted log entries with a
/// Share button (so the user can send logs to Hermes) and a Clear button.
struct LogsView: View {
    @ObservedObject private var store = LogStore.shared
    @State private var showShare = false

    var body: some View {
        Group {
            if store.entries.isEmpty {
                ContentUnavailableView(
                    "No logs yet",
                    systemImage: "doc.text",
                    description: Text("Run the app and reproduce the issue, then come back here."))
            } else {
                List {
                    ForEach(store.entries.reversed()) { entry in
                        VStack(alignment: .leading, spacing: 2) {
                            HStack {
                                Text(entry.level.rawValue)
                                    .font(.caption2.weight(.bold))
                                    .foregroundColor(color(for: entry.level))
                                Text(entry.timestamp, style: .time)
                                    .font(.caption2)
                                    .foregroundColor(.secondary)
                            }
                            Text(entry.message)
                                .font(.caption.monospaced())
                                .textSelection(.enabled)
                        }
                        .padding(.vertical, 2)
                    }
                }
            }
        }
        .navigationTitle("Logs")
        .navigationBarTitleDisplayMode(.inline)
        .toolbar {
            ToolbarItem(placement: .primaryAction) {
                Button {
                    showShare = true
                } label: {
                    Image(systemName: "square.and.arrow.up")
                }
                .disabled(store.entries.isEmpty)
            }
            ToolbarItem(placement: .cancellationAction) {
                Button("Clear") { store.clear() }
                    .disabled(store.entries.isEmpty)
            }
        }
        .sheet(isPresented: $showShare) {
            ShareSheet(text: store.text)
        }
    }

    private func color(for level: LogStore.Entry.Level) -> Color {
        switch level {
        case .info: return .secondary
        case .warn: return .orange
        case .error: return .red
        }
    }
}

/// Minimal share sheet wrapper (ShareLink is iOS 16+; this is explicit).
struct ShareSheet: UIViewControllerRepresentable {
    let text: String

    func makeUIViewController(context: Context) -> UIActivityViewController {
        UIActivityViewController(activityItems: [text], applicationActivities: nil)
    }
    func updateUIViewController(_ uiViewController: UIActivityViewController,
                                context: Context) {}
}