import SwiftUI
import ProxyCore
import GRDB

struct DNSSpoofingView: View {
    @State private var isEnabled = IPCManager.shared.isDNSSpoofingEnabled
    @State private var rules: [DNSSpoofRule] = []
    @State private var showAddRule = false
    @State private var observation: AnyDatabaseCancellable?

    private let rulesRepo = RulesRepository()

    var body: some View {
        List {
            Section {
                ToggleHeaderView(
                    title: "DNS Spoofing",
                    description: "Redirect domain resolution to a different target. Useful for routing production domains to development servers.",
                    isEnabled: $isEnabled
                )
                .onChange(of: isEnabled) { _, newValue in
                    IPCManager.shared.isDNSSpoofingEnabled = newValue
                    IPCManager.shared.post(.configurationChanged)
                }
            }
            .listRowInsets(EdgeInsets())

            Section("Rules") {
                if rules.isEmpty {
                    EmptyStateView(
                        icon: "network",
                        title: "No DNS Spoofing Rules",
                        subtitle: "Tap + to create a new rule."
                    )
                } else {
                    ForEach(rules) { rule in
                        VStack(alignment: .leading, spacing: 4) {
                            HStack {
                                Text(rule.sourceDomain)
                                    .font(.subheadline)
                                Image(systemName: "arrow.right")
                                    .font(.caption)
                                    .foregroundStyle(.secondary)
                                Text(rule.targetDomain)
                                    .font(.subheadline)
                                    .foregroundStyle(.blue)
                            }
                        }
                    }
                    .onDelete { indexSet in
                        for index in indexSet {
                            if let id = rules[index].id {
                                try? rulesRepo.deleteDNSSpoofRule(id: id)
                            }
                        }
                    }
                }
            }
        }
        .navigationTitle("DNS Spoofing")
        .toolbar {
            ToolbarItem(placement: .topBarTrailing) {
                Button { showAddRule = true } label: {
                    Image(systemName: "plus")
                }
            }
        }
        .sheet(isPresented: $showAddRule) {
            NavigationStack {
                Form {
                    // TODO: Add DNS spoof rule creation form
                    Text("DNS Spoofing rule creation")
                }
                .navigationTitle("New DNS Rule")
                .navigationBarTitleDisplayMode(.inline)
                .toolbar {
                    ToolbarItem(placement: .cancellationAction) {
                        Button("Cancel") { showAddRule = false }
                    }
                }
            }
        }
        .task {
            observation = rulesRepo.observeDNSSpoofRules()
                .start(in: DatabaseManager.shared.dbPool) { error in
                    print("DNS Spoof observation error: \(error)")
                } onChange: { newRules in
                    rules = newRules
                }
        }
    }
}