Latest Chapter provenance: one derived line naming the actor class (#152)

backend/internal/web/admin_series_detail.go

@@ -33,6 +33,12 @@ type seriesDetailView struct {
 	// owner's, and it dies with the stamp (a machine write of the number).
 	Corrected string
 
+	// Provenance is the actor class behind the current Chapter: "correction",
+	// "sighting" or "machine read"; "" while the Series was never read, when
+	// the line is not rendered. Derived from the same anonymous stamps the
+	// marks above read — no Reader identity crosses here.
+	Provenance string
+
 	// Marks, one per hygiene fact, rendered only while it holds.
 	Unpollable     bool // no SeriesURL to fetch
 	NoCover        bool
@@ -130,6 +136,24 @@ func (h *Handler) seriesDetailView(a store.AdminSeries) seriesDetailView {
 		v.Checked = since(time.Now(), time.UnixMilli(a.LatestCheckedAt))
 	}
 	v.Corrected = correctedAge(time.Now(), a.LatestCorrectedAt)
+
+	// Provenance: the actor class behind the current number, evaluated in the
+	// order the classes outrank one another — the owner's stamp, which a
+	// Correction leaves standing and a machine write clears (issue #149); a
+	// raising Reader, which a Correction drops; then any check stamp at all.
+	// An Acquisition reads as a machine read because it stamps
+	// latest_checked_at exactly as a Poll does, so the two are
+	// indistinguishable the moment it finishes; telling them apart would need
+	// the column this project declines to add (spec #135), and the one
+	// actionable case — acquired once, never read again — is already the
+	// unchecked filter.
+	if a.LatestCorrectedAt != 0 {
+		v.Provenance = "correction"
+	} else if a.RaisedByReader {
+		v.Provenance = "sighting"
+	} else if a.LatestCheckedAt != 0 {
+		v.Provenance = "machine read"
+	}
 	return v
 }
 

backend/internal/web/admin_series_detail_test.go

@@ -0,0 +1,34 @@
+package web
+
+import (
+	"testing"
+
+	"bookmarkmanager/backend/internal/store"
+)
+
+// seriesDetailView derives the provenance line from the three stamps the
+// admin projection already carries: the correction stamp outranks a raising
+// Reader, which outranks a check stamp, and a Series with none of the three
+// renders no line at all — it was never read, and no actor class is true of
+// it. Acquisition stamps latest_checked_at exactly as a Poll does, so an
+// acquired value lands in the same "machine read" class (#152).
+func TestSeriesDetailViewProvenance(t *testing.T) {
+	cases := []struct {
+		name string
+		a    store.AdminSeries
+		want string
+	}{
+		{"correction stamp", store.AdminSeries{LatestCorrectedAt: 1}, "correction"},
+		{"raising reader only", store.AdminSeries{RaisedByReader: true}, "sighting"},
+		{"check stamp only", store.AdminSeries{LatestCheckedAt: 1}, "machine read"},
+		{"correction outranks sighting", store.AdminSeries{LatestCorrectedAt: 1, RaisedByReader: true}, "correction"},
+		{"none of the three", store.AdminSeries{}, ""},
+	}
+	for _, tc := range cases {
+		t.Run(tc.name, func(t *testing.T) {
+			if got := (&Handler{}).seriesDetailView(tc.a).Provenance; got != tc.want {
+				t.Fatalf("Provenance = %q, want %q", got, tc.want)
+			}
+		})
+	}
+}

backend/internal/web/templates/series-detail.html

@@ -38,10 +38,13 @@
 
 {{/* series-detail-meta is the meta line, and the answer a Check now or
      correction press on the detail page swaps into its place: the same marks,
-     re-rendered after the stamp so the pending and corrected markers show. */}}
+     re-rendered after the stamp so the pending and corrected markers — and
+     the provenance line beside the number — describe the value they sit
+     next to. */}}
 {{define "series-detail-meta"}}
 <div class="detail-meta" id="detail-meta">
   <span>ch {{.Chapter}}</span>
+  {{if .Provenance}}<span>{{.Provenance}}</span>{{end}}
   <span>checked {{.Checked}}</span>
   <span>{{.Readers}} readers</span>
   {{if .Corrected}}<span class="mark">{{.Corrected}}</span>{{end}}
@@ -51,4 +54,4 @@
   {{if .Orphan}}<span class="mark">orphan</span>{{end}}
   {{if .SightingRaised}}<span class="mark">sighting-raised</span>{{end}}
 </div>
-{{end}}
+{{end}}