import SwiftUI

struct LoginView: View {
    @Environment(AuthSession.self) private var auth

    @State private var email = ""
    @State private var password = ""

    var body: some View {
        ScrollView {
            VStack(spacing: 28) {
                hero
                pitch
                loginCard
                registerCard
            }
            .padding(.horizontal, 24)
            .padding(.vertical, 32)
        }
        .scrollDismissesKeyboard(.interactively)
    }

    // MARK: - Hero

    private var hero: some View {
        VStack(spacing: 12) {
            Image("AppIconHero")
                .resizable()
                .scaledToFit()
                .frame(height: 120)
            Text("Ban Yaro Go")
                .font(.largeTitle.bold())
            Text("Die deutschsprachige Hunde-Plattform — jetzt mit nativem GPS-Tracking.")
                .font(.callout)
                .foregroundStyle(.secondary)
                .multilineTextAlignment(.center)
        }
    }

    // MARK: - Pitch (für Neue)

    private var pitch: some View {
        VStack(alignment: .leading, spacing: 14) {
            feature(icon: "map.fill", title: "Gassi-Touren aufzeichnen", subtitle: "GPS-Tracking auch im Hintergrund — mit Pause, Live Activity und HealthKit-Sync.")
            feature(icon: "person.2.fill", title: "Hunde-Community", subtitle: "Gassi-Treffen, Tierärzte und Orte in deiner Nähe.")
            feature(icon: "book.fill", title: "Tagebuch & Impfpass", subtitle: "Alles rund um deinen Hund an einem Ort.")
            feature(icon: "exclamationmark.shield.fill", title: "Giftköder-Alarm", subtitle: "Warnungen aus deiner Region direkt aufs iPhone.")
        }
        .padding(18)
        .frame(maxWidth: .infinity, alignment: .leading)
        .background(.background.secondary, in: RoundedRectangle(cornerRadius: 16))
    }

    private func feature(icon: String, title: String, subtitle: String) -> some View {
        HStack(alignment: .top, spacing: 12) {
            Image(systemName: icon)
                .font(.title3)
                .foregroundStyle(Color.accentColor)
                .frame(width: 28)
            VStack(alignment: .leading, spacing: 2) {
                Text(title).font(.subheadline.bold())
                Text(subtitle)
                    .font(.caption)
                    .foregroundStyle(.secondary)
            }
        }
    }

    // MARK: - Login (für bestehende User)

    private var loginCard: some View {
        VStack(spacing: 12) {
            HStack {
                Text("Schon angemeldet?")
                    .font(.headline)
                Spacer()
            }

            TextField("E-Mail", text: $email)
                .textContentType(.emailAddress)
                .keyboardType(.emailAddress)
                .textInputAutocapitalization(.never)
                .autocorrectionDisabled()
                .padding()
                .background(.background, in: RoundedRectangle(cornerRadius: 12))

            SecureField("Passwort", text: $password)
                .textContentType(.password)
                .padding()
                .background(.background, in: RoundedRectangle(cornerRadius: 12))

            if let error = auth.errorMessage {
                Text(error)
                    .font(.footnote)
                    .foregroundStyle(.red)
                    .multilineTextAlignment(.center)
                    .frame(maxWidth: .infinity)
            }

            Button {
                Task {
                    await auth.login(
                        email: email.trimmingCharacters(in: .whitespacesAndNewlines),
                        password: password
                    )
                }
            } label: {
                Group {
                    if auth.isLoggingIn {
                        ProgressView().tint(.white)
                    } else {
                        Text("Login").bold()
                    }
                }
                .frame(maxWidth: .infinity, minHeight: 50)
            }
            .background(Color.accentColor, in: RoundedRectangle(cornerRadius: 12))
            .foregroundStyle(.white)
            .disabled(auth.isLoggingIn || email.isEmpty || password.isEmpty)
        }
        .padding(18)
        .background(.background.secondary, in: RoundedRectangle(cornerRadius: 16))
    }

    // MARK: - Register (für Neue)

    private var registerCard: some View {
        VStack(spacing: 10) {
            Text("Neu hier?")
                .font(.headline)
            Text("banyaro.app ist **kostenlos**, **DSGVO-konform** und wird in Deutschland gehostet — kein App-Store-Konto nötig.")
                .font(.footnote)
                .foregroundStyle(.secondary)
                .multilineTextAlignment(.center)

            if let url = URL(string: "https://banyaro.app/#settings?tab=register") {
                Link(destination: url) {
                    HStack(spacing: 8) {
                        Image(systemName: "person.crop.circle.badge.plus")
                        Text("Kostenlos registrieren").bold()
                        Image(systemName: "arrow.up.right")
                            .font(.caption.bold())
                    }
                    .frame(maxWidth: .infinity, minHeight: 50)
                }
                .background(Color.accentColor.opacity(0.15), in: RoundedRectangle(cornerRadius: 12))
                .foregroundStyle(Color.accentColor)
            }

            Text("Öffnet die Registrierung im Browser. Danach mit den neuen Zugangsdaten oben einloggen.")
                .font(.caption2)
                .foregroundStyle(.tertiary)
                .multilineTextAlignment(.center)
        }
        .padding(18)
        .background(.background.secondary, in: RoundedRectangle(cornerRadius: 16))
    }
}

#Preview {
    LoginView()
        .environment(AuthSession())
}