indeed_ai_job_search/indeed_ai_job_search/App/RootShellView.swift

//
//  RootShellView.swift
//  indeed_ai_job_search
//

import SwiftUI

struct RootShellView: View {
    let dependencies: AppDependencies

    @State private var selection: SidebarItem = .jobSearch
    @State private var jobSearchVM: JobSearchViewModel
    @State private var savedJobsVM: SavedJobsViewModel
    @State private var alertsVM: JobAlertsViewModel
    @State private var settingsVM: SettingsViewModel
    @State private var showFiltersSheet = false

    init(dependencies: AppDependencies) {
        self.dependencies = dependencies
        _jobSearchVM = State(initialValue: JobSearchViewModel(dependencies: dependencies))
        _savedJobsVM = State(initialValue: SavedJobsViewModel(dependencies: dependencies))
        _alertsVM = State(initialValue: JobAlertsViewModel(dependencies: dependencies))
        _settingsVM = State(initialValue: SettingsViewModel())
    }

    var body: some View {
        GeometryReader { proxy in
            let width = proxy.size.width
            let showInlineFilters = width >= AppSpacing.mediumBreakpoint && selection == .jobSearch

            HStack(spacing: 0) {
                AppSidebarView(
                    selection: $selection,
                    unreadAlertCount: alertsVM.unreadCount
                )
                .frame(width: AppSpacing.sidebarWidth)
                .overlay(alignment: .trailing) {
                    Rectangle()
                        .fill(AppColors.border)
                        .frame(width: 1)
                }

                VStack(spacing: 0) {
                    topUtilityBar

                    detail(showInlineFilters: showInlineFilters)
                        .frame(maxWidth: .infinity, maxHeight: .infinity)
                }
                .frame(maxWidth: .infinity, maxHeight: .infinity)
            }
            .background(AppColors.backgroundPrimary)
        }
        .preferredColorScheme(settingsVM.preferredColorScheme)
        .sheet(isPresented: $showFiltersSheet) {
            NavigationStack {
                FiltersPanelView(
                    criteria: $jobSearchVM.criteria,
                    onReset: { jobSearchVM.resetFilters() },
                    onChange: { jobSearchVM.applyFiltersAndRefresh() }
                )
                .toolbar {
                    ToolbarItem(placement: .cancellationAction) {
                        Button("Done") { showFiltersSheet = false }
                    }
                }
            }
            .frame(minWidth: 360, minHeight: 560)
        }
        .sheet(isPresented: $alertsVM.showNotificationCenter) {
            NotificationCenterSheet(events: alertsVM.events)
        }
        .onChange(of: selection) { _, newValue in
            if newValue == .savedJobs {
                savedJobsVM.refreshFromStore()
            }
        }
        .background(keyboardShortcuts)
    }

    /// Notifications sit top-right above mid content and filters.
    private var topUtilityBar: some View {
        HStack(spacing: AppSpacing.sm) {
            Spacer(minLength: 0)

            Button {
                alertsVM.openNotificationCenter()
            } label: {
                Image(systemName: alertsVM.unreadCount > 0 ? "bell.badge" : "bell")
                    .font(.system(size: 15, weight: .medium))
                    .foregroundStyle(AppColors.textSecondary)
                    .frame(width: 32, height: 32)
                    .contentShape(Rectangle())
            }
            .buttonStyle(.plain)
            .help("Notification center")
            .accessibilityLabel("Notifications")
        }
        .padding(.horizontal, AppSpacing.xl)
        .frame(height: AppSpacing.windowChromeTop)
        .frame(maxWidth: .infinity)
        .background(AppColors.backgroundPrimary)
    }

    @ViewBuilder
    private func detail(showInlineFilters: Bool) -> some View {
        switch selection {
        case .jobSearch:
            AIJobSearchView(
                viewModel: jobSearchVM,
                showsInlineFilters: showInlineFilters,
                onRequestFiltersSheet: { showFiltersSheet = true }
            )
        case .savedJobs:
            SavedJobsView(viewModel: savedJobsVM) {
                selection = .jobSearch
            }
        case .jobAlerts:
            JobAlertsView(viewModel: alertsVM)
        case .settings:
            SettingsView(viewModel: settingsVM)
        }
    }

    private var keyboardShortcuts: some View {
        Button("") {
            selection = .jobSearch
            jobSearchVM.focusSearchField.toggle()
        }
        .keyboardShortcut("f", modifiers: .command)
        .opacity(0)
        .frame(width: 0, height: 0)
        .accessibilityHidden(true)
    }
}

#Preview("Root Shell") {
    RootShellView(dependencies: .preview)
        .frame(width: 1280, height: 820)
}