ui: 30d repo-size sparkline on every dashboard host row

internal/server/http/ui_handlers.go

@@ -5,8 +5,10 @@ import (
 	"encoding/base64"
 	"encoding/json"
 	"errors"
+	"html/template"
 	"io/fs"
 	"log/slog"
+	"math"
 	stdhttp "net/http"
 	"net/url"
 	"sort"
@@ -24,6 +26,7 @@ import (
 	"gitea.dcglab.co.uk/steve/restic-manager/internal/server/ws"
 	"gitea.dcglab.co.uk/steve/restic-manager/internal/store"
 	"gitea.dcglab.co.uk/steve/restic-manager/internal/version"
+	"gitea.dcglab.co.uk/steve/restic-manager/internal/web/sparkline"
 	"gitea.dcglab.co.uk/steve/restic-manager/web"
 )
 
@@ -196,6 +199,10 @@ type dashboardHostRow struct {
 	// TargetVersion is the server's build version, surfaced in the
 	// chip's tooltip and label.
 	TargetVersion string
+	// RepoSparklineSVG is a server-rendered inline SVG showing the
+	// 30-day repo-size trend. Empty-state SVG (em-dash) is returned
+	// when no history rows exist for the host.
+	RepoSparklineSVG template.HTML
 }
 
 // pickRunAllSchedule returns the ID of the single schedule whose
@@ -296,6 +303,20 @@ func (s *Server) handleUIDashboard(w stdhttp.ResponseWriter, r *stdhttp.Request)
 				}
 			}
 		}
+		since := time.Now().UTC().AddDate(0, 0, -30)
+		pts, herr := s.deps.Store.ListHostRepoStatsHistory(r.Context(), h.ID, since)
+		if herr != nil {
+			slog.Warn("ui dashboard: list repo history", "host_id", h.ID, "err", herr)
+		}
+		sparkPoints := make([]float64, len(pts))
+		for i, p := range pts {
+			if p.TotalSizeBytes == nil {
+				sparkPoints[i] = math.NaN()
+			} else {
+				sparkPoints[i] = float64(*p.TotalSizeBytes)
+			}
+		}
+		row.RepoSparklineSVG = sparkline.RenderSparkline(sparkPoints, 88, 20)
 		rows = append(rows, row)
 	}