frontend/app/p/[treeId]/page.tsx

@@ -1,25 +1,30 @@
 "use client";
 
 import Link from "next/link";
-import { useParams } from "next/navigation";
+import { useParams, useRouter } from "next/navigation";
 import { useEffect, useMemo, useState } from "react";
 
 import { api } from "@/lib/api/client";
 import type { components } from "@/lib/api/schema";
 import { Card, CardContent } from "@/components/ui/card";
 import { Input } from "@/components/ui/input";
+import { PublicTreeChart } from "@/components/public-tree-chart";
 
 type Person = components["schemas"]["PersonRead"];
 type Event = components["schemas"]["EventRead"];
+type Relationship = components["schemas"]["RelationshipRead"];
 type Tree = components["schemas"]["PublicTreeRead"];
 
 // Public, no-login view of a tree. Everything here is already redacted by the
 // /api/v1/public surface (living people show as "Living person").
 export default function PublicTreePage() {
   const { treeId } = useParams<{ treeId: string }>();
+  const router = useRouter();
   const [tree, setTree] = useState<Tree | null>(null);
   const [people, setPeople] = useState<Person[]>([]);
   const [events, setEvents] = useState<Event[]>([]);
+  const [rels, setRels] = useState<Relationship[]>([]);
+  const [focusId, setFocusId] = useState<string | null>(null);
   const [status, setStatus] = useState<"loading" | "ready" | "notfound">("loading");
   const [search, setSearch] = useState("");
 
@@ -34,14 +39,22 @@ export default function PublicTreePage() {
         setStatus("notfound");
         return;
       }
-      const [p, e] = await Promise.all([
+      const [p, e, r] = await Promise.all([
         api.GET("/api/v1/public/trees/{tree_id}/persons", { params: { path: { tree_id: treeId } } }),
         api.GET("/api/v1/public/trees/{tree_id}/events", { params: { path: { tree_id: treeId } } }),
+        api.GET("/api/v1/public/trees/{tree_id}/relationships", {
+          params: { path: { tree_id: treeId } },
+        }),
       ]);
       if (cancelled) return;
+      const ppl = p.data ?? [];
+      const home = t.data.home_person_id;
+      const homeId = home && ppl.some((x) => x.id === home) ? home : null;
       setTree(t.data);
-      setPeople(p.data ?? []);
+      setPeople(ppl);
       setEvents(e.data ?? []);
+      setRels(r.data ?? []);
+      setFocusId((cur) => cur ?? homeId ?? ppl[0]?.id ?? null);
       setStatus("ready");
     })();
     return () => {
@@ -97,12 +110,26 @@ export default function PublicTreePage() {
         </p>
       </div>
 
+      {focusId && people.length > 0 && (
+        <PublicTreeChart
+          people={people}
+          rels={rels}
+          events={events}
+          focusId={focusId}
+          onFocus={setFocusId}
+          onOpen={(id) => router.push(`/p/${treeId}/persons/${id}`)}
+        />
+      )}
+
+      <div className="space-y-3">
+        <h2 className="font-serif text-base font-semibold">All people</h2>
         <Input
           className="w-72"
           placeholder="Search people…"
           value={search}
           onChange={(e) => setSearch(e.target.value)}
         />
+      </div>
 
       <Card className="overflow-hidden">
         <CardContent className="p-0">

frontend/app/page.tsx

@@ -31,6 +31,9 @@ export default function Home() {
             <img src="/provenance-logo-plain.svg" alt="Provenance" className="h-7 w-auto" />
           </Link>
           <nav className="flex items-center gap-5 text-sm">
+            <Link href="/explore" className="text-[var(--muted)] hover:text-[var(--foreground)]">
+              Explore
+            </Link>
             <Link href="/trees" className="text-[var(--muted)] hover:text-[var(--foreground)]">
               Trees
             </Link>
@@ -66,6 +69,11 @@ export default function Home() {
                   Sign in
                 </Button>
               </Link>
+              <Link href="/explore">
+                <Button size="lg" variant="ghost">
+                  Explore public trees
+                </Button>
+              </Link>
             </div>
           </div>
 

frontend/components/public-tree-chart.tsx

@@ -0,0 +1,177 @@
+"use client";
+
+// Vendored family-chart styles (the package blocks the CSS subpath export).
+import "../app/trees/[id]/tree/chart.css";
+
+import { useCallback, useEffect, useMemo, useRef } from "react";
+
+import type { components } from "@/lib/api/schema";
+
+type Person = components["schemas"]["PersonRead"];
+type Relationship = components["schemas"]["RelationshipRead"];
+type Event = components["schemas"]["EventRead"];
+
+function splitName(name: string | null | undefined): [string, string] {
+  const t = (name ?? "").trim().split(/\s+/).filter(Boolean);
+  if (t.length <= 1) return [name ?? "", ""];
+  return [t.slice(0, -1).join(" "), t[t.length - 1]];
+}
+
+/**
+ * Read-only family-chart hourglass for the public surface. Same renderer the
+ * member tree view uses (incl. the cycle-sanitisation that keeps a bad graph
+ * from blowing the stack), fed by already-redacted public data. Clicking a card
+ * recenters; `onOpen` links out to the person's public page.
+ */
+export function PublicTreeChart({
+  people,
+  rels,
+  events,
+  focusId,
+  onFocus,
+  onOpen,
+}: {
+  people: Person[];
+  rels: Relationship[];
+  events: Event[];
+  focusId: string | null;
+  onFocus: (id: string) => void;
+  onOpen?: (id: string) => void;
+}) {
+  const containerRef = useRef<HTMLDivElement>(null);
+  // eslint-disable-next-line @typescript-eslint/no-explicit-any
+  const chartRef = useRef<any>(null);
+
+  const parentsOf = useCallback(
+    (id: string) =>
+      rels.filter((x) => x.type === "parent_child" && x.person_to_id === id).map((x) => x.person_from_id),
+    [rels],
+  );
+  const partnersOf = useCallback(
+    (id: string) =>
+      rels
+        .filter((x) => x.type === "partnership" && (x.person_from_id === id || x.person_to_id === id))
+        .map((x) => (x.person_from_id === id ? x.person_to_id : x.person_from_id)),
+    [rels],
+  );
+  const years = useMemo(() => {
+    const m = new Map<string, string>();
+    for (const ev of events) {
+      if (ev.person_id && ev.event_type === "birth" && !m.has(ev.person_id)) {
+        const y = ev.date_start ? ev.date_start.slice(0, 4) : ev.date_value ?? "";
+        if (y) m.set(ev.person_id, y);
+      }
+    }
+    return m;
+  }, [events]);
+  const byId = useMemo(() => new Map(people.map((p) => [p.id, p])), [people]);
+  const nameOf = useCallback((id: string) => byId.get(id)?.primary_name ?? "person", [byId]);
+
+  // Build the chart when the data changes (not on focus — recenter handles that).
+  useEffect(() => {
+    if (people.length === 0 || !containerRef.current) return;
+    let cancelled = false;
+    (async () => {
+      const alive = new Set(people.map((pp) => pp.id));
+      const ok = (ids: string[], self: string) =>
+        [...new Set(ids)].filter((id) => alive.has(id) && id !== self);
+
+      const parentsMap = new Map<string, string[]>();
+      const childrenMap = new Map<string, string[]>();
+      const isAncestorOf = (ancestor: string, of: string): boolean => {
+        const stack = [...(parentsMap.get(of) ?? [])];
+        const seen = new Set<string>();
+        while (stack.length) {
+          const n = stack.pop()!;
+          if (n === ancestor) return true;
+          if (seen.has(n)) continue;
+          seen.add(n);
+          for (const p of parentsMap.get(n) ?? []) stack.push(p);
+        }
+        return false;
+      };
+      for (const pp of people) {
+        const accepted: string[] = [];
+        for (const par of ok(parentsOf(pp.id), pp.id)) {
+          if (isAncestorOf(pp.id, par)) continue;
+          accepted.push(par);
+          parentsMap.set(pp.id, accepted);
+          childrenMap.set(par, [...(childrenMap.get(par) ?? []), pp.id]);
+        }
+        parentsMap.set(pp.id, accepted);
+      }
+
+      const data = people.map((pp) => {
+        const [fn, ln] = splitName(pp.primary_name);
+        return {
+          id: pp.id,
+          data: {
+            "first name": fn || "Unnamed",
+            "last name": ln,
+            birthday: years.get(pp.id) ?? "",
+            gender: pp.gender === "female" ? "F" : "M",
+          },
+          rels: {
+            spouses: ok(partnersOf(pp.id), pp.id),
+            parents: parentsMap.get(pp.id) ?? [],
+            children: childrenMap.get(pp.id) ?? [],
+          },
+        };
+      });
+
+      const f3 = await import("family-chart");
+      if (cancelled || !containerRef.current) return;
+      try {
+        containerRef.current.innerHTML = "";
+        const chart = f3.createChart(containerRef.current, data);
+        chart.setCardHtml().setCardDisplay([["first name", "last name"], ["birthday"]]);
+        chart.setOrientationHorizontal();
+        chart.setAncestryDepth?.(3);
+        chart.setProgenyDepth?.(2);
+        chart.setAfterUpdate?.(() => {
+          const md = chart.getMainDatum?.();
+          const id = md?.id ?? md?.data?.id;
+          if (id) onFocus(id);
+        });
+        chartRef.current = chart;
+        if (focusId) chart.updateMainId(focusId);
+        chart.updateTree({ initial: true });
+      } catch (err) {
+        console.error("public tree render failed", err);
+        if (containerRef.current) containerRef.current.innerHTML = "";
+      }
+    })();
+    return () => {
+      cancelled = true;
+    };
+    // eslint-disable-next-line react-hooks/exhaustive-deps
+  }, [people, rels, events]);
+
+  // Recenter when the focus changes without rebuilding the chart.
+  useEffect(() => {
+    if (focusId && chartRef.current) {
+      chartRef.current.updateMainId?.(focusId);
+      chartRef.current.updateTree?.();
+    }
+  }, [focusId]);
+
+  return (
+    <div className="space-y-2">
+      <div
+        ref={containerRef}
+        className="f3 rounded-xl border border-[var(--border)]"
+        style={{ width: "100%", height: "70vh", background: "var(--surface)" }}
+      />
+      <div className="flex flex-wrap items-center justify-between gap-2">
+        <p className="text-sm text-[var(--muted)]">
+          Drag to pan · scroll to zoom · click a person to recenter.
+        </p>
+        {focusId && onOpen && (
+          <button onClick={() => onOpen(focusId)} className="text-sm text-bronze hover:underline">
+            Open {nameOf(focusId)} →
+          </button>
+        )}
+      </div>
+    </div>
+  );
+}