Outpost/Outpost/Features/Collections/ContentView_macOS.swift

#if os(macOS)
import SwiftUI
import OutlineKit

struct ContentView_macOS: View {
    @Environment(SessionStore.self) private var session
    @State private var selectedCollection: OutlineCollection?
    @State private var documentPath: [OutlineDocument] = []
    @State private var globalSearchQuery = ""
    @State private var contextualSearchQuery = ""

    private var trimmedGlobalQuery: String {
        globalSearchQuery.trimmingCharacters(in: .whitespacesAndNewlines)
    }

    var body: some View {
        NavigationSplitView {
            VStack(spacing: 0) {
                SidebarSearchField(text: $globalSearchQuery)
                Divider()
                sidebar
                AccountFooter()
            }
            .navigationSplitViewColumnWidth(min: 220, ideal: 260)
        } detail: {
            detail
        }
        .navigationTitle(session.teamName ?? "Outpost")
        .toolbar {
            // Per HIG: "sidebar-toggle/back controls appear at the far leading
            // edge, followed by the view title" — this is that title, not
            // centered. It doesn't collide with the back button because they're
            // mutually exclusive: whenever a document's pushed (back button
            // visible), this shows the document's own title instead of falling
            // back to the workspace badge.
            ToolbarItem(placement: .navigation) {
                leadingToolbarContent
            }
        }
        // Attached at this level (not inside the detail's NavigationStack) so
        // it reliably renders in the shared window toolbar instead of a
        // per-screen one that can get lost when nested more deeply.
        .searchable(
            text: $contextualSearchQuery,
            placement: .toolbar,
            prompt: selectedCollection.map { "Search \($0.name)" } ?? "Search"
        )
    }

    @ViewBuilder
    private var leadingToolbarContent: some View {
        Group {
            if !trimmedGlobalQuery.isEmpty {
                HStack(spacing: 6) {
                    Image(systemName: "magnifyingglass")
                    Text("Search")
                }
            } else if let currentDocument = documentPath.last, let selectedCollection {
                // Back button (system-provided) → collection → document, so the
                // hierarchy reads left to right instead of just the leaf title.
                HStack(spacing: 6) {
                    CollectionRowView(collection: selectedCollection)
                    Image(systemName: "chevron.right")
                        .font(.caption2.weight(.semibold))
                        .foregroundStyle(.tertiary)
                    if let emoji = currentDocument.emoji {
                        Text(emoji)
                    } else {
                        Image(systemName: "doc.text")
                    }
                    Text(currentDocument.title.isEmpty ? "Untitled" : currentDocument.title)
                        .lineLimit(1)
                }
            } else if let selectedCollection {
                CollectionRowView(collection: selectedCollection)
            } else {
                HStack(spacing: 8) {
                    AvatarBadge(avatarURL: session.teamAvatarURL, placeholderSystemImage: "text.book.closed.fill")
                    Text(session.teamName ?? "Outpost")
                        .lineLimit(1)
                }
            }
        }
        .font(.headline)
        .padding(.horizontal, 10)
        .padding(.vertical, 4)
        .background(.fill.tertiary, in: Capsule())
    }

    @ViewBuilder
    private var sidebar: some View {
        if let apiClient = session.apiClient {
            CollectionsTreeView(
                apiClient: apiClient,
                selectedCollection: $selectedCollection,
                onSelectDocument: selectDocument
            )
        } else {
            ContentUnavailableView("Not Signed In", systemImage: "person.crop.circle.badge.exclamationmark")
        }
    }

    /// `documentPath = [document]` (replacing a same-size array in one step)
    /// unreliably updates `NavigationStack` on macOS — the stack can silently
    /// keep showing the previous document. Popping to root and pushing again
    /// as two separate state updates (so SwiftUI processes them as two render
    /// passes) is the reliable version of the same operation.
    private func selectDocument(_ collection: OutlineCollection, _ document: OutlineDocument) {
        selectedCollection = collection
        documentPath = []
        Task { @MainActor in
            documentPath = [document]
        }
    }

    @ViewBuilder
    private var detail: some View {
        if let apiClient = session.apiClient {
            // A fresh NavigationStack per collection (or when entering/leaving
            // search), so switching either also clears any pushed document.
            NavigationStack(path: $documentPath) {
                Group {
                    if !trimmedGlobalQuery.isEmpty {
                        GlobalSearchResultsView(apiClient: apiClient, query: trimmedGlobalQuery)
                    } else if let selectedCollection {
                        CollectionOverviewView(
                            apiClient: apiClient,
                            collection: selectedCollection,
                            searchQuery: $contextualSearchQuery
                        )
                    } else {
                        ContentUnavailableView(
                            "No Collection Selected",
                            systemImage: "sidebar.left",
                            description: Text("Choose a collection to see its documents.")
                        )
                    }
                }
                .navigationDestination(for: OutlineDocument.self) { document in
                    DocumentReaderView(apiClient: apiClient, document: document)
                }
            }
            .id(trimmedGlobalQuery.isEmpty ? (selectedCollection?.id ?? "none") : "search")
        } else {
            ContentUnavailableView("Not Signed In", systemImage: "person.crop.circle.badge.exclamationmark")
        }
    }
}
#endif