import SwiftUI

enum ServiceStatus {
    case pending
    case operational
    case degraded
    case outage

    var description: String {
        switch self {
        case .pending:
            return "Fetching service status"
        case .operational:
            return "No issues detected"
        case .degraded:
            return "Performance degraded"
        case .outage:
            return "Service disruption"
        }
    }

    var color: Color {
        switch self {
        case .pending:
            return .gray
        case .operational:
            return .green
        case .degraded:
            return .orange
        case .outage:
            return .red
        }
    }
}

struct HomeView: View {
    @State private var isEnabled = false
    @State private var selectedBlocklist: BlocklistOption = .secure
    @State private var serviceStatus: ServiceStatus = .operational

    private let falsePositiveURL = URL(string: "https://www.sr2.uk/contact")!
    private let statusURL = URL(string:
        "https://status.sr2.uk/")!
    private let tosURL = URL(string: "https://www.sr2.uk/terms")!
    private let privacyPolicyURL = URL(string: "https://www.sr2.uk/privacy")!

    var body: some View {
        NavigationStack {
            List {
                
                // Main toggle section
                Section {
                    HStack {
                        VStack(alignment: .leading, spacing: 4) {
                            Text("DNS Protection")
                                .font(.headline)
                            Text(isEnabled ? "Active" : "Inactive")
                                .font(.caption)
                                .foregroundStyle(isEnabled ? .green : .secondary)
                        }

                        Spacer()

                        Toggle("", isOn: $isEnabled)
                            .labelsHidden()
                            .tint(.green)
                    }
                    .padding(.vertical, 4)
                }

                // Blocklist selection
                Section {
                    ForEach(BlocklistOption.allCases) { option in
                        BlocklistRow(
                            option: option,
                            isSelected: selectedBlocklist == option
                        )
                        .contentShape(Rectangle())
                        .onTapGesture {
                            guard option.enabled else { return }
                            withAnimation(.spring(duration: 0.3)) {
                                selectedBlocklist = option
                            }
                        }
                        .opacity(option.enabled ? 1 : 0.6)
                    }
                } header: {
                    Text("Blocklist")
                } footer: {
                    Text("Select the level of protection for your DNS queries")
                }

                // Status section
                if isEnabled {
                    Section {
                        HStack {
                            Label("Status", systemImage: "checkmark.circle.fill")
                                .foregroundStyle(.green)
                            Spacer()
                            Text("Connected")
                                .foregroundStyle(.secondary)
                        }

                        HStack {
                            Label("Server", systemImage: "server.rack")
                            Spacer()
                            Text(selectedBlocklist.server)
                                .foregroundStyle(.secondary)
                                .font(.system(.body, design: .monospaced))
                        }
                        
                        HStack {
                            Label("IPv4", systemImage: "globe")
                            Spacer()
                            Text(selectedBlocklist.ipv4)
                                .foregroundStyle(.secondary)
                                .font(.system(.body, design: .monospaced))
                        }
                        
                        HStack {
                            Label("IPv6", systemImage: "globe")
                            Spacer()
                            Text(selectedBlocklist.ipv6)
                                .foregroundStyle(.secondary)
                                .font(.system(.body, design: .monospaced))
                        }

                        HStack {
                            Label("Domains in blocklist", systemImage: "xmark.shield.fill")
                            Spacer()
                            BlockedCount()
                                .foregroundStyle(.secondary)
                        }
                    } header: {
                        Text("Connection Details")
                    }
                }

                // Support section
                Section {
                    Link(destination: falsePositiveURL) {
                        HStack {
                            Label {
                                Text("Report False Positive")
                            } icon: {
                                Image(systemName: "exclamationmark.bubble")
                                    .foregroundStyle(.orange)
                            }

                            Spacer()

                            Image(systemName: "arrow.up.right.square")
                                .font(.caption)
                                .foregroundStyle(.secondary)
                        }
                    }.foregroundStyle(.primary)
                } footer: {
                    Text("Submit incorrectly blocked domains for review")
                }
                
                // Service status section
                Section {
                    Link(destination: statusURL) {
                        HStack(spacing: 12) {
                            Circle()
                                .fill(serviceStatus.color)
                                .frame(width: 12, height: 12)
                            
                            VStack(alignment: .leading, spacing: 4) {
                                Text("Service Status")
                                    .font(.headline)
                                Text(serviceStatus.description)
                                    .font(.caption)
                                    .foregroundStyle(.secondary)
                            }
                            
                            Spacer()
                            
                            Image(systemName: "arrow.up.right.square")
                                .font(.caption)
                                .foregroundStyle(.secondary)
                        }
                        .padding(.vertical, 4)
                    }.foregroundStyle(.primary)

                    Link(destination: tosURL) {
                        HStack(spacing: 12) {
                            Image(systemName: "doc.text")
                            Text("Terms of Service")
                            Spacer()
                            Image(systemName: "arrow.up.right.square")
                                .font(.caption)
                                .foregroundStyle(.secondary)
                            
                        }
                    }.foregroundStyle(.primary)
                    
                    Link(destination: privacyPolicyURL) {
                        HStack(spacing: 12) {
                            Image(systemName: "doc.text")
                            Text("Privacy Policy")
                            Spacer()
                            Image(systemName: "arrow.up.right.square")
                                .font(.caption)
                                .foregroundStyle(.secondary)
                            
                        }
                    }.foregroundStyle(.primary)
                }
            }
            .navigationTitle("SR2® Cloud DNS")
            .animation(.default, value: isEnabled)
        }
    }
}

#Preview {
    HomeView()
}