Implemented phase 2 for the POC prototype in the Website service.

Services/Website/Sources/Library/Internal/Pages/ListingPage.swift

@@ -18,20 +18,26 @@ struct ListingPage {
     /// Other listings from the same shop.
     let related: [Listing]
 
+    /// The signed-in viewer, or `nil` when signed out.
+    let viewer: Viewer?
+
     // MARK: Initializers
 
     /// Creates the detail screen of a listing.
     /// - Parameters:
     ///   - listing: the listing shown.
     ///   - related: other listings from the same shop.
+    ///   - viewer: the signed-in viewer, or `nil` (the default) when signed out.
     ///   - assetVersion: the version token appended to the page's asset URLs, or `nil` (the default) to leave them unversioned.
     ///   - analytics: the analytics tracker embedded in the document head, or `nil` (the default) to omit it.
     init(
         listing: Listing,
         related: [Listing],
+        viewer: Viewer? = nil,
         assetVersion: String? = nil,
         analytics: Analytics? = nil
     ) {
+        self.viewer = viewer
         self.analytics = analytics
         self.assetVersion = assetVersion
         self.listing = listing
@@ -48,7 +54,10 @@ extension ListingPage: Page {
     // MARK: Computed
 
     var content: some HTML {
-        SiteLayout(active: listing.kind) {
+        SiteLayout(
+            active: listing.kind,
+            viewer: viewer
+        ) {
             div(.class("page listing")) {
                 breadcrumb
                 div(.class("listing__body")) {
@@ -201,48 +210,54 @@ private extension ListingPage {
                         listing.acceptsOffers ? " · accepts offers" : ""
                     }
                 }
-                a(
-                    .class("button button--sm"),
-                    .href(signIn)
-                ) {
-                    Icon(.bookmark, size: 16)
-                    "Save"
+                if viewer == nil {
+                    a(
+                        .class("button button--sm"),
+                        .href(.Route.signIn(returningTo: listing.path))
+                    ) {
+                        Icon(.bookmark, size: 16)
+                        "Save"
+                    }
+                } else {
+                    Unavailable("Save", modifier: "button--sm")
                 }
             }
             div(.class("buy-box__actions")) {
                 a(
                     .class("button button--primary button--lg"),
-                    .href(signIn)
+                    .href(gated(.Route.buy(listing.slug)))
                 ) {
                     "Buy now"
                 }
                 if listing.acceptsOffers {
                     a(
                         .class("button button--outline button--lg"),
-                        .href(signIn)
+                        .href(gated(.Route.offer(listing.slug)))
                     ) {
                         "Make an offer"
                     }
                 }
                 a(
                     .class("button button--bare button--lg"),
-                    .href(signIn)
+                    .href(gated(.Route.message(listing: listing.slug)))
                 ) {
                     Icon(.message, size: 16)
                     "Message seller"
                 }
             }
-            p(.class("gate-note")) {
-                Icon(.lock, size: 16)
-                span {
-                    "Buying, offers, saving and messages need a signed-in account. "
-                    a(
-                        .class("gate-note__link"),
-                        .href(signIn)
-                    ) {
-                        "Sign in or join with a passkey"
+            if viewer == nil {
+                p(.class("gate-note")) {
+                    Icon(.lock, size: 16)
+                    span {
+                        "Buying, offers, saving and messages need a signed-in account. "
+                        a(
+                            .class("gate-note__link"),
+                            .href(.Route.signIn(returningTo: listing.path))
+                        ) {
+                            "Sign in or join with a passkey"
+                        }
+                        " — browsing stays open to everyone."
                     }
-                    " — browsing stays open to everyone."
                 }
             }
         }
@@ -302,9 +317,13 @@ private extension ListingPage {
         }
     }
 
-    /// The sign-in screen, returning to this listing.
-    var signIn: String {
-        .Route.signIn(returningTo: listing.path)
+    // MARK: Methods
+
+    /// The path a gated action on this listing leads to.
+    func gated(
+        _ path: String
+    ) -> String {
+        .Route.gated(path, from: listing.path, viewer: viewer)
     }
 
 }