import SwiftUI
import LabWiseKit

@Observable
final class ProfileViewModel {
    var profile: UserProfile?
    var isLoading = false
    var isSaving = false
    var isEditing = false
    var errorMessage: String?

    // Editable fields
    var piFirstName = ""
    var bldgCode = ""
    var lab = ""
    var contact = ""

    private let profileClient = ProfileClient()
    private let authClient = AuthClient()

    func load() async {
        isLoading = true
        defer { isLoading = false }
        do {
            let p = try await profileClient.get()
            profile = p
            populateFields(from: p)
        } catch {
            // Profile may not exist yet — that's OK
        }
    }

    func save() async {
        isSaving = true
        defer { isSaving = false }
        do {
            let body = UserProfileUpsertBody(
                piFirstName: piFirstName,
                bldgCode: bldgCode,
                lab: lab,
                contact: contact.isEmpty ? nil : contact
            )
            let updated = try await profileClient.upsert(body)
            profile = updated
            populateFields(from: updated)
            isEditing = false
        } catch {
            errorMessage = "Failed to save profile."
        }
    }

    func signOut() async {
        try? await authClient.signOut()
        await MainActor.run {
            AppState.shared.signedOut()
        }
    }

    private func populateFields(from p: UserProfile) {
        piFirstName = p.piFirstName
        bldgCode = p.bldgCode
        lab = p.lab
        contact = p.contact ?? ""
    }
}

struct ProfileView: View {
    @Environment(AppState.self) private var appState
    @State private var viewModel = ProfileViewModel()

    var body: some View {
        NavigationStack {
            Form {
                if let user = appState.currentUser {
                    Section("Account") {
                        LabeledContent("Email", value: user.email)
                    }
                }

                Section("Lab Info") {
                    if viewModel.isEditing {
                        TextField("PI First Name", text: $viewModel.piFirstName)
                        TextField("Building Code", text: $viewModel.bldgCode)
                        TextField("Lab", text: $viewModel.lab)
                        TextField("Contact", text: $viewModel.contact)
                    } else {
                        LabeledContent("PI First Name", value: viewModel.piFirstName.isEmpty ? "—" : viewModel.piFirstName)
                        LabeledContent("Building Code", value: viewModel.bldgCode.isEmpty ? "—" : viewModel.bldgCode)
                        LabeledContent("Lab", value: viewModel.lab.isEmpty ? "—" : viewModel.lab)
                        LabeledContent("Contact", value: viewModel.contact.isEmpty ? "—" : viewModel.contact)
                    }
                }

                Section {
                    Link(destination: URL(string: "https://labwise.wahwa.com/privacy")!) {
                        Text("Privacy Policy")
                    }
                }

                Section {
                    Button(role: .destructive) {
                        Task { await viewModel.signOut() }
                    } label: {
                        HStack {
                            Spacer()
                            Text("Sign Out")
                            Spacer()
                        }
                    }
                }
            }
            .navigationTitle("Profile")
            .toolbar {
                ToolbarItem(placement: .topBarTrailing) {
                    if viewModel.isEditing {
                        Button("Save") {
                            Task { await viewModel.save() }
                        }
                        .disabled(viewModel.isSaving)
                    } else {
                        Button("Edit") {
                            viewModel.isEditing = true
                        }
                    }
                }
                if viewModel.isEditing {
                    ToolbarItem(placement: .topBarLeading) {
                        Button("Cancel") {
                            viewModel.isEditing = false
                            if let p = viewModel.profile {
                                viewModel.piFirstName = p.piFirstName
                                viewModel.bldgCode = p.bldgCode
                                viewModel.lab = p.lab
                                viewModel.contact = p.contact ?? ""
                            }
                        }
                    }
                }
            }
            .alert("Error", isPresented: .constant(viewModel.errorMessage != nil)) {
                Button("OK") { viewModel.errorMessage = nil }
            } message: {
                Text(viewModel.errorMessage ?? "")
            }
        }
        .task {
            await viewModel.load()
        }
    }
}