import SwiftUI

enum HermesAppMode: String {
    case demo
    case live
}

struct RootView: View {
    @StateObject private var localization = LocalizationStore()
    @EnvironmentObject private var analytics: HermesAnalyticsClient
    @EnvironmentObject private var repository: HermesRepository

    let mode: HermesAppMode
    let onModeSelected: (HermesAppMode) -> Void
    let onStartSession: (String, HermesAppMode) -> Void

    var body: some View {
        ZStack(alignment: .top) {
            HermesTheme.background
                .ignoresSafeArea()

            RoundView(onRetry: { onStartSession(localization.localeCode, mode) })
                .ignoresSafeArea()

            topChrome
        }
        .environmentObject(localization)
        .onAppear {
            analytics.track("app_opened", attributes: ["screen_name": "round", "mode": mode.rawValue])
            analytics.track("screen_viewed", attributes: ["screen_name": "round", "mode": mode.rawValue])
        }
        .task(id: "\(localization.localeCode)-\(mode.rawValue)") {
            onStartSession(localization.localeCode, mode)
        }
        .task {
            while !Task.isCancelled {
                try? await Task.sleep(nanoseconds: 5_000_000_000)
                await analytics.flush(using: repository)
            }
        }
    }

    private var topChrome: some View {
        HStack(alignment: .top, spacing: 12) {
            VStack(alignment: .leading, spacing: 6) {
                Text(localization.string(for: "app.name"))
                    .font(.headline.weight(.bold))
                    .foregroundStyle(HermesTheme.textPrimary)
                Text(mode == .demo ? localization.string(for: "mode.demo" ) : localization.string(for: "mode.live"))
                    .font(.caption.weight(.semibold))
                    .foregroundStyle(HermesTheme.textSecondary)
            }

            Spacer(minLength: 12)

            VStack(alignment: .trailing, spacing: 10) {
                modeToggle
                localeToggle
            }
        }
        .padding(.horizontal, HermesTheme.screenPadding)
        .padding(.top, 16)
    }

    private var modeToggle: some View {
        HStack(spacing: 8) {
            modeButton(title: localization.string(for: "mode.demo"), appMode: .demo)
            modeButton(title: localization.string(for: "mode.live"), appMode: .live)
        }
    }

    private var localeToggle: some View {
        HStack(spacing: 8) {
            localeButton(title: localization.localeName(for: "en"), localeCode: "en")
            localeButton(title: localization.localeName(for: "sv"), localeCode: "sv")
        }
    }

    private func modeButton(title: String, appMode: HermesAppMode) -> some View {
        let isSelected = mode == appMode

        return Button {
            onModeSelected(appMode)
            analytics.track("mode_changed", attributes: ["mode": appMode.rawValue])
        } label: {
            Text(title)
                .font(.caption.weight(.bold))
                .padding(.horizontal, 12)
                .padding(.vertical, 8)
                .foregroundStyle(isSelected ? HermesTheme.background : HermesTheme.textPrimary)
                .background(isSelected ? HermesTheme.accent : HermesTheme.surfaceElevated.opacity(0.9))
                .clipShape(Capsule())
        }
    }

    private func localeButton(title: String, localeCode: String) -> some View {
        let isSelected = localization.localeCode == localeCode

        return Button {
            localization.setLocale(localeCode)
            analytics.track("locale_changed", attributes: ["locale_code": localeCode])
        } label: {
            Text(title)
                .font(.caption.weight(.bold))
                .padding(.horizontal, 12)
                .padding(.vertical, 8)
                .foregroundStyle(isSelected ? HermesTheme.background : HermesTheme.textPrimary)
                .background(isSelected ? HermesTheme.accent : HermesTheme.surfaceElevated.opacity(0.9))
                .clipShape(Capsule())
        }
    }
}