import SwiftUI

/// Shown inline wherever a user is about to configure a physical port that
/// `ConnectionService.checkPortConflict(interfaceName:)` found already carrying other
/// configuration — originally the Setup Wizard's LAN step only (found.md #1's "Port-Konflikt-
/// Prüfung"), now also the Experte tab's generic `.interfacePick` fields (per explicit request:
/// "die Abfrage vom Einrichten-Assistenten auf Expert anwenden ... mit allen Warnungen").
/// Requires two separate confirmations before the app is allowed to clear it — per explicit
/// request: this silently overriding a port's existing role (an active WAN dial-up, a bridge
/// membership, a manually-set address) previously wasn't visible to the user at all beyond
/// `DhcpServerCommandBuilder`'s own unconditional bridge detach; this makes the consequences
/// explicit and opt-in instead.
struct PortConflictWarningView: View {
    let conflict: PortConflict
    let isAcknowledged: Bool
    let appLanguage: String
    /// Wizard: resolution runs later, batched with everything else at "Jetzt anwenden" — the
    /// final confirmation dialog says so, and that a port switch above still undoes it. Experte
    /// tab: there's no separate review/apply step, "Anlegen"/"Speichern" runs it immediately —
    /// a different final-confirmation message reflects that instead.
    let immediateApply: Bool
    let onConfirm: () -> Void

    @State private var showConsequencesConfirmation = false
    @State private var showFinalConfirmation = false

    var body: some View {
        if isAcknowledged {
            Label("\(conflict.interfaceName) " + L10n.t("wird beim Anwenden freigemacht", appLanguage), systemImage: "checkmark.shield")
                .appFont(.caption)
                .foregroundStyle(.orange)
        } else {
            VStack(alignment: .leading, spacing: 6) {
                Label(L10n.t("Port", appLanguage) + " \(conflict.interfaceName) " + L10n.t("ist nicht frei", appLanguage), systemImage: "exclamationmark.triangle.fill")
                    .appFont(.subheadline, bold: true)
                    .foregroundStyle(.red)
                ForEach(Array(conflict.reasons.enumerated()), id: \.offset) { _, reason in
                    Text("• \(reason.description)")
                        .appFont(.caption)
                }
                Text(L10n.t("Wähle oben einen anderen, freien Port — oder mache diesen jetzt frei. Die bestehende Konfiguration wird dabei entfernt.", appLanguage))
                    .appFont(.caption)
                    .foregroundStyle(.secondary)
                Button(L10n.t("Port jetzt freimachen…", appLanguage), role: .destructive) {
                    showConsequencesConfirmation = true
                }
            }
            .padding(10)
            .background(RoundedRectangle(cornerRadius: 8).fill(Color.red.opacity(0.08)))
            .confirmationDialog(
                L10n.t("Port", appLanguage) + " \(conflict.interfaceName) " + L10n.t("freimachen?", appLanguage),
                isPresented: $showConsequencesConfirmation,
                titleVisibility: .visible
            ) {
                Button(L10n.t("Fortfahren", appLanguage), role: .destructive) {
                    showFinalConfirmation = true
                }
                Button(L10n.t("Abbrechen", appLanguage), role: .cancel) {}
            } message: {
                Text(consequenceText)
            }
            .confirmationDialog(
                L10n.t("Wirklich sicher?", appLanguage),
                isPresented: $showFinalConfirmation,
                titleVisibility: .visible
            ) {
                Button(L10n.t("Ja, endgültig freimachen", appLanguage), role: .destructive) {
                    onConfirm()
                }
                Button(L10n.t("Abbrechen", appLanguage), role: .cancel) {}
            } message: {
                Text(immediateApply
                    ? L10n.t("Wird sofort ausgeführt, sobald du unten auf \"Anlegen\"/\"Speichern\" klickst.", appLanguage)
                    : L10n.t("Tatsächlich ausgeführt wird das erst mit \"Jetzt anwenden\" am Ende des Assistenten — bis dahin kannst du das rückgängig machen, indem du hier oben einen anderen Port wählst.", appLanguage))
            }
        }
    }

    private var consequenceText: String {
        ([L10n.t("Folgendes wird entfernt, bevor", appLanguage) + " \(conflict.interfaceName) " + L10n.t("als neues Netzwerk eingerichtet wird:", appLanguage)]
            + conflict.reasons.map { "• \($0.description)" }
            + [L10n.t("Bestehender Datenverkehr über diesen Port (z.B. eine laufende Internetverbindung oder Geräte im bisherigen Netz) wird dadurch unterbrochen.", appLanguage)])
            .joined(separator: "\n")
    }
}