Fase B5: temporal/linear graph view mode

Adds a third :temporal view mode alongside :tags-and-objects and
:all-pages. The backend reuses build-all-pages-graph's node/link shape
unchanged (every node already carries :block/created-at); only the
client-side pixi layout differs, arranging nodes along a fixed
chronological timeline (oldest first, staggered across a few lanes)
instead of running the force simulation, following the existing
grid-layout fixed-position precedent.

src/main/frontend/components/graph.cljs

@@ -35,8 +35,9 @@
 
 (defn- valid-view-mode
   [view-mode]
-  (if (= view-mode :all-pages)
+  (case view-mode
-    :all-pages
+    :all-pages :all-pages
+    :temporal :temporal
     :tags-and-objects))
 
 (defn- clamp-number
@@ -335,7 +336,13 @@
         :class "graph-mode-tab"}
        (view-mode-tab-label
         (t :graph/view-mode-all-pages)
-        (and loading? (= view-mode :all-pages))))))}))
+        (and loading? (= view-mode :all-pages))))
+      (shui/tabs-trigger
+       {:value "temporal"
+        :class "graph-mode-tab"}
+       (view-mode-tab-label
+        (t :graph/view-mode-temporal)
+        (and loading? (= view-mode :temporal))))))}))
 
 (defn- tags-group
   [settings set-settings! available-tags selected-tag-ids tag-query set-tag-query!]
@@ -430,17 +437,20 @@
         link-distance (valid-link-distance (:link-distance settings))
         grid-layout? (true? (:grid-layout? settings))
         show-journals? (not (false? (:show-journals? settings)))
-        depth-disabled? (depth-control-disabled? selected-nodes)]
+        depth-disabled? (depth-control-disabled? selected-nodes)
+        temporal? (= view-mode :temporal)]
     (settings-group
      {:settings settings
       :set-settings! set-settings!
       :id :layout
       :title (t :graph/layout)
-      :meta (t :graph/layout-force)
+      :meta (if temporal? (t :graph/layout-temporal) (t :graph/layout-force))
       :children [:div.graph-layout-controls
                  [:div.graph-layout-stats
                   [:span (t :graph/node-count (count (:nodes graph-data)))]
                   [:span (t :graph/link-count (count (:links graph-data)))]]
+                 (when-not temporal?
+                   [:<>
                     (layout-slider
                      {:label (t :graph/layout-depth)
                       :value depth
@@ -457,7 +467,7 @@
                       :max 180
                       :step 6
                       :on-change #(set-settings! (fn [settings]
-                                                 (assoc settings :link-distance (valid-link-distance %))))})
+                                                    (assoc settings :link-distance (valid-link-distance %))))})])
                  (when (= view-mode :tags-and-objects)
                    [:<>
                     (layout-toggle

src/main/frontend/extensions/graph/pixi/logic.cljs

@@ -483,6 +483,7 @@
   (case view-mode
     :all-pages :all-pages
     :page :page
+    :temporal :temporal
     :tags-and-objects))
 
 (defn labels-visible-by-default?
@@ -1000,6 +1001,26 @@
     (vec (concat linked-nodes
                  (place-isolated-ring-nodes isolated degree dark? isolated-start-radius)))))
 
+(def ^:private temporal-lane-count 6)
+(def ^:private temporal-node-gap 46)
+(def ^:private temporal-lane-gap 30)
+
+(defn- temporal-layout-nodes
+  "Lays out nodes along a fixed, linear timeline ordered by :block/created-at
+   (oldest first), instead of running the force simulation. Nodes without a
+   timestamp sort first. Staggered across a few lanes on the y-axis so nodes
+   created close together don't fully overlap."
+  [nodes degree dark?]
+  (->> nodes
+       (sort-by (fn [node] [(or (:block/created-at node) 0) (str (:id node))]))
+       (map-indexed
+        (fn [idx node]
+          (let [lane (mod idx temporal-lane-count)
+                x (* idx temporal-node-gap)
+                y (* lane temporal-lane-gap)]
+            (decorate-node node degree dark? x y))))
+       vec))
+
 (defn- all-pages-fast-layout-nodes
   [nodes degree dark?]
   (let [node-count (count nodes)
@@ -1383,8 +1404,17 @@
          mode (layout-mode (count nodes) view-mode)
          fast-all-pages? (and (= :fast mode)
                               (= view-mode :all-pages))]
-     (if fast-all-pages?
+     (cond
+       (= view-mode :temporal)
+       (let [node-id-set (set (map :id nodes))
+             filtered-links (keep-links-with-nodes links node-id-set)
+             degree (build-degree-map filtered-links)]
+         (temporal-layout-nodes nodes degree dark?))
+
+       fast-all-pages?
        (all-pages-fast-layout-nodes nodes (build-fast-degree-map nodes links) dark?)
+
+       :else
        (let [node-id-set (set (map :id nodes))
              filtered-links (keep-links-with-nodes links node-id-set)
              degree (build-degree-map filtered-links)

src/main/frontend/worker/graph_view.cljs

@@ -48,8 +48,9 @@
 
 (defn- normalize-view-mode
   [view-mode]
-  (if (= view-mode :all-pages)
+  (case view-mode
-    :all-pages
+    :all-pages :all-pages
+    :temporal :temporal
     :tags-and-objects))
 
 (def ^:private large-all-pages-fast-threshold 10000)
@@ -923,7 +924,11 @@
         result (case view-mode
                  :tags-and-objects
                  (build-tags-and-objects-graph db)
-                 :all-pages
+                 (:all-pages :temporal)
+                 ;; :temporal reuses the same node/link shape as :all-pages
+                 ;; (every node already carries :block/created-at); only the
+                 ;; client-side layout differs, arranging nodes on a fixed
+                 ;; timeline instead of running the force simulation.
                  (build-all-pages-graph db opts))]
     (assoc result :meta {:view-mode view-mode})))
 

src/resources/dicts/en.edn

@@ -750,6 +750,7 @@
  :graph/layout-force "Force graph"
  :graph/layout-grid-layout "Grid layout"
  :graph/layout-link-distance "Link distance"
+ :graph/layout-temporal "Timeline"
  :graph/layout-show-journals "Show journals"
  :graph/leave-action "Leave this graph"
  :graph/leave-confirm-desc "Are you sure you want to leave this graph?"
@@ -787,6 +788,7 @@
  :graph/view-mode "View mode"
  :graph/view-mode-all-pages "All pages"
  :graph/view-mode-tags "Tags"
+ :graph/view-mode-temporal "Timeline"
 
  :graph.diagnostics/checksum-failed-error "Failed to compute graph checksum diagnostics."
  :graph.diagnostics/checksum-recomputed-success "Checksum recomputed. Recomputed: {1}, local: {2}, remote: {3}. Downloaded {4}.edn with {5} blocks and checksum attributes {6}."

src/test/frontend/extensions/graph/pixi/logic_test.cljs

@@ -0,0 +1,17 @@
+(ns frontend.extensions.graph.pixi.logic-test
+  (:require [cljs.test :refer [deftest is testing]]
+            [frontend.extensions.graph.pixi.logic :as logic]))
+
+(deftest temporal-view-mode-lays-out-nodes-on-a-fixed-timeline
+  (let [nodes [{:id "a" :kind "page" :block/created-at 300}
+               {:id "b" :kind "page" :block/created-at 100}
+               {:id "c" :kind "page" :block/created-at 200}]
+        links []
+        result (logic/layout-nodes nodes links :temporal false)
+        by-id (into {} (map (juxt :id identity) result))]
+    (testing "nodes are ordered chronologically along the x-axis, oldest first"
+      (is (< (:x (by-id "b")) (:x (by-id "c")) (:x (by-id "a")))))
+    (testing "every node gets a fixed position and radius, no force simulation"
+      (is (every? #(and (number? (:x %)) (number? (:y %)) (number? (:radius %))) result)))
+    (testing "re-running layout for the same input is deterministic"
+      (is (= result (logic/layout-nodes nodes links :temporal false))))))