import SwiftUI

struct ProfileView: View {
    @StateObject private var viewModel = ProfileViewModel()
    @Environment(\.dismiss) var dismiss
    @FocusState private var focusedField: Field?

    enum Field {
        case firstName, lastName, email
    }

    var body: some View {
        NavigationView {
            if viewModel.isLoadingUser {
                VStack {
                    ProgressView()
                    Text("Loading profile...")
                        .font(.subheadline)
                        .foregroundColor(Color.appTextSecondary)
                        .padding(.top, 8)
                }
            } else {
                Form {
                    Section {
                        VStack(spacing: 16) {
                            Image(systemName: "person.circle.fill")
                                .font(.system(size: 60))
                                .foregroundStyle(Color.appPrimary.gradient)

                            Text("Profile Settings")
                                .font(.title2)
                                .fontWeight(.bold)
                                .foregroundColor(Color.appTextPrimary)
                        }
                        .frame(maxWidth: .infinity)
                        .padding(.vertical)
                    }
                    .listRowBackground(Color.clear)

                    Section {
                        TextField("First Name", text: $viewModel.firstName)
                            .textInputAutocapitalization(.words)
                            .autocorrectionDisabled()
                            .focused($focusedField, equals: .firstName)
                            .submitLabel(.next)
                            .onSubmit {
                                focusedField = .lastName
                            }

                        TextField("Last Name", text: $viewModel.lastName)
                            .textInputAutocapitalization(.words)
                            .autocorrectionDisabled()
                            .focused($focusedField, equals: .lastName)
                            .submitLabel(.next)
                            .onSubmit {
                                focusedField = .email
                            }
                    } header: {
                        Text("Personal Information")
                    }
                    .listRowBackground(Color.appBackgroundSecondary)

                    Section {
                        TextField("Email", text: $viewModel.email)
                            .textInputAutocapitalization(.never)
                            .autocorrectionDisabled()
                            .keyboardType(.emailAddress)
                            .focused($focusedField, equals: .email)
                            .submitLabel(.done)
                            .onSubmit {
                                viewModel.updateProfile()
                            }
                    } header: {
                        Text("Contact")
                    } footer: {
                        Text("Email is required and must be unique")
                    }
                    .listRowBackground(Color.appBackgroundSecondary)

                    if let errorMessage = viewModel.errorMessage {
                        Section {
                            HStack {
                                Image(systemName: "exclamationmark.triangle.fill")
                                    .foregroundColor(Color.appError)
                                Text(errorMessage)
                                    .foregroundColor(Color.appError)
                                    .font(.subheadline)
                            }
                        }
                        .listRowBackground(Color.appBackgroundSecondary)
                    }

                    if let successMessage = viewModel.successMessage {
                        Section {
                            HStack {
                                Image(systemName: "checkmark.circle.fill")
                                    .foregroundColor(Color.appPrimary)
                                Text(successMessage)
                                    .foregroundColor(Color.appPrimary)
                                    .font(.subheadline)
                            }
                        }
                        .listRowBackground(Color.appBackgroundSecondary)
                    }

                    Section {
                        Button(action: viewModel.updateProfile) {
                            HStack {
                                Spacer()
                                if viewModel.isLoading {
                                    ProgressView()
                                } else {
                                    Text("Save Changes")
                                        .fontWeight(.semibold)
                                }
                                Spacer()
                            }
                        }
                        .disabled(viewModel.isLoading || viewModel.email.isEmpty)
                    }
                    .listRowBackground(Color.appBackgroundSecondary)
                }
                .listStyle(.plain)
                .scrollContentBackground(.hidden)
                .background(Color.appBackgroundPrimary)
                .navigationTitle("Profile")
                .navigationBarTitleDisplayMode(.inline)
                .toolbar {
                    ToolbarItem(placement: .navigationBarLeading) {
                        Button("Cancel") {
                            dismiss()
                        }
                    }
                }
                .onChange(of: viewModel.firstName) { _, _ in
                    viewModel.clearMessages()
                }
                .onChange(of: viewModel.lastName) { _, _ in
                    viewModel.clearMessages()
                }
                .onChange(of: viewModel.email) { _, _ in
                    viewModel.clearMessages()
                }
                .handleErrors(
                    error: viewModel.errorMessage,
                    onRetry: { viewModel.updateProfile() }
                )
            }
        }
    }
}

#Preview {
    ProfileView()
}