Improvements to fitness page

- Data now comes from a calendar
- Hovering in charts shows day info
- Optical enhancements to chart rendering
- Allow setting/showing goal weight
- Allow toggeling between absolute and zoomed in weight axis

README.md

@@ -73,7 +73,7 @@ Bookmarkable shortcuts: `<diary>/today/`, `<diary>/this-month/`, `<diary>/this-y
 
 ## Fitness
 
-With `type = fitness`, a folder shows weight charts (daily and weekly mean, with your goal) below its content. Copy the [Waistline](https://github.com/davidhealey/waistline) app's export into the folder as `waistline_export.json`. Each new export replaces the old file.
+With `type = fitness`, a folder shows weight charts (daily and weekly mean) below its content. The weights come from the calendars with the `weight` role (see [Calendars](#calendars)). Add `weight-goal = 85` to the folder's `.page-settings` to draw a goal line.
 
 ## Calendars
 

assets/fitness/fitness.js

@@ -1,10 +1,74 @@
-// Fitness dashboard range dropdowns: changing one reloads the page with that
+// Fitness dashboard range dropdowns and "absolute" checkboxes: changing one
-// chart's query parameter updated. Plain GET navigation — each range is a
+// reloads the page with that chart's query parameter updated. Plain GET
-// distinct, bookmarkable view, so no postReplace/history handling is needed.
+// navigation — each view is distinct and bookmarkable, so no
+// postReplace/history handling is needed.
 document.addEventListener('change', function (e) {
-    var sel = e.target.closest('[data-fitness-range]');
-    if (!sel) return;
     var url = new URL(window.location.href);
+    var sel = e.target.closest('[data-fitness-range]');
+    var abs = e.target.closest('[data-fitness-absolute]');
+    if (sel) {
         url.searchParams.set(sel.dataset.fitnessRange, sel.value);
+    } else if (abs) {
+        if (abs.checked) url.searchParams.set(abs.dataset.fitnessAbsolute, '1');
+        else url.searchParams.delete(abs.dataset.fitnessAbsolute);
+    } else {
+        return;
+    }
     window.location.href = url.toString();
 });
+
+// Hover tooltip: the pointer snaps to the data point nearest in time. Dots
+// are sorted by x, so a binary search finds it; the tooltip sits above the
+// point and is clamped to the chart panel.
+function fitnessNearest(dots, x) {
+    var lo = 0, hi = dots.length - 1;
+    while (lo < hi) {
+        var mid = (lo + hi) >> 1;
+        if (dots[mid].cx.baseVal.value < x) lo = mid + 1; else hi = mid;
+    }
+    if (lo > 0 && x - dots[lo - 1].cx.baseVal.value < dots[lo].cx.baseVal.value - x) lo--;
+    return dots[lo];
+}
+
+function fitnessHide(svg) {
+    var chart = svg.closest('.fitness-chart');
+    svg.classList.remove('is-hover');
+    chart.querySelector('.fitness-tip').hidden = true;
+}
+
+document.addEventListener('pointermove', function (e) {
+    var svg = e.target.closest && e.target.closest('.fitness-svg');
+    document.querySelectorAll('.fitness-svg').forEach(function (other) {
+        if (other !== svg) fitnessHide(other);
+    });
+    if (!svg) return;
+    var dots = svg.querySelectorAll('.chart-dot');
+    if (!dots.length) return;
+    var ctm = svg.getScreenCTM();
+    if (!ctm) return;
+    var pt = new DOMPoint(e.clientX, e.clientY).matrixTransform(ctm.inverse());
+    var dot = fitnessNearest(dots, pt.x);
+    var cx = dot.cx.baseVal.value, cy = dot.cy.baseVal.value;
+
+    var cursor = svg.querySelector('.chart-cursor');
+    cursor.setAttribute('x1', cx);
+    cursor.setAttribute('x2', cx);
+    var focus = svg.querySelector('.chart-focus');
+    focus.setAttribute('cx', cx);
+    focus.setAttribute('cy', cy);
+    svg.classList.add('is-hover');
+
+    var chart = svg.closest('.fitness-chart');
+    var tip = chart.querySelector('.fitness-tip');
+    tip.firstElementChild.textContent = dot.dataset.date;
+    tip.lastElementChild.textContent = dot.dataset.value;
+    tip.hidden = false;
+    var box = chart.getBoundingClientRect();
+    var at = new DOMPoint(cx, cy).matrixTransform(ctm);
+    var left = at.x - box.left - tip.offsetWidth / 2;
+    left = Math.max(0, Math.min(left, box.width - tip.offsetWidth));
+    var top = at.y - box.top - tip.offsetHeight - 10;
+    if (top < 0) top = at.y - box.top + 10;
+    tip.style.left = left + 'px';
+    tip.style.top = top + 'px';
+});

assets/fitness/main.html

@@ -2,19 +2,23 @@
 <section class="fitness-chart panel">
     <div class="fitness-chart-header row space-between">
         <span class="caption">{{.Title}}</span>
+        <div class="row fitness-controls">
+            <label class="fitness-absolute"><input type="checkbox" data-fitness-absolute="{{.Param}}-absolute"{{if .Absolute}} checked{{end}}> Absolute</label>
             <select class="input fitness-range" data-fitness-range="{{.Param}}" aria-label="{{.Title}} time range">
                 {{range .Options}}<option value="{{.Value}}"{{if .Selected}} selected{{end}}>{{.Label}}</option>{{end}}
             </select>
         </div>
+    </div>
     {{if .Empty}}
     <p class="fitness-empty is-empty">No data in this range.</p>
     {{else}}
-    <svg class="fitness-svg" viewBox="0 0 {{.ViewW}} {{.ViewH}}" role="img" aria-label="{{.Title}}">
+    <svg class="fitness-svg{{if .Dense}} is-dense{{end}}" viewBox="0 0 {{.ViewW}} {{.ViewH}}" role="img" aria-label="{{.Title}}">
         {{range .YTicks}}
         <line class="chart-grid" x1="{{$.PlotX}}" y1="{{.Pos}}" x2="{{$.PlotR}}" y2="{{.Pos}}"/>
         <text class="chart-label" x="{{$.YLabelX}}" y="{{.Pos}}" text-anchor="end" dominant-baseline="middle">{{.Label}}</text>
         {{end}}
         {{range .XTicks}}
+        <line class="chart-grid" x1="{{.Pos}}" y1="{{$.PlotY}}" x2="{{.Pos}}" y2="{{$.PlotB}}"/>
         <text class="chart-label" x="{{.Pos}}" y="{{$.XLabelY}}" text-anchor="{{.Anchor}}">{{.Label}}</text>
         {{end}}
         <line class="chart-axis" x1="{{.PlotX}}" y1="{{.PlotY}}" x2="{{.PlotX}}" y2="{{.PlotB}}"/>
@@ -23,13 +27,16 @@
         <polyline class="chart-line" points="{{.}}"/>
         {{end}}
         {{range .Dots}}
-        <circle class="chart-dot" cx="{{.X}}" cy="{{.Y}}" r="2.5"><title>{{.Title}}</title></circle>
+        <circle class="chart-dot" cx="{{.X}}" cy="{{.Y}}" r="2.5" data-date="{{.Date}}" data-value="{{.Value}}"/>
         {{end}}
         {{if .Goal}}
         <line class="chart-goal" x1="{{.PlotX}}" y1="{{.Goal.Y}}" x2="{{.PlotR}}" y2="{{.Goal.Y}}"/>
         <text class="chart-goal-label" x="{{.PlotR}}" y="{{.Goal.LabelY}}" text-anchor="end">{{.Goal.Label}}</text>
         {{end}}
+        <line class="chart-cursor" x1="0" y1="{{.PlotY}}" x2="0" y2="{{.PlotB}}"/>
+        <circle class="chart-focus" r="4"/>
     </svg>
+    <div class="fitness-tip" hidden><strong></strong><span></span></div>
     {{end}}
 </section>
 {{end}}

assets/style.css

@@ -837,8 +837,10 @@ aside.sidebar:empty { display: none; }
    Server-rendered inline SVG charts. Geometry comes precomputed from Go;
    colors and strokes are applied here via classes so the inline SVG follows
    the theme palette. */
-.fitness-chart { padding: var(--space-3); }
+.fitness-chart { position: relative; padding: var(--space-3); }
 .fitness-chart-header { margin-bottom: var(--space-2); }
+.fitness-controls { gap: var(--space-3); }
+.fitness-absolute { display: flex; align-items: center; gap: var(--space-1); font-size: var(--font-sm); color: var(--text-muted); }
 .fitness-range { width: auto; font-size: var(--font-sm); }
 .fitness-empty {
     border: var(--border-dashed);
@@ -852,8 +854,24 @@ aside.sidebar:empty { display: none; }
 .fitness-svg .chart-label { fill: var(--text-muted); font-size: var(--font-xs); }
 .fitness-svg .chart-line { fill: none; stroke: var(--link); stroke-width: 1.5; }
 .fitness-svg .chart-dot { fill: var(--link); }
-.fitness-svg .chart-goal { stroke: var(--primary-hover); stroke-dasharray: 4 3; }
+.fitness-svg.is-dense .chart-dot { display: none; }
-.fitness-svg .chart-goal-label { fill: var(--primary-hover); font-size: var(--font-xs); }
+.fitness-svg:not(.is-hover) :is(.chart-cursor, .chart-focus) { display: none; }
+.fitness-svg .chart-cursor { stroke: var(--text-muted); stroke-dasharray: 2 2; }
+.fitness-svg .chart-focus { fill: var(--link-hover); stroke: var(--bg); stroke-width: 1.5; }
+.fitness-svg .chart-goal { stroke: var(--danger); stroke-dasharray: 4 3; }
+.fitness-svg .chart-goal-label { fill: var(--danger-hover); font-size: var(--font-xs); }
+.fitness-tip {
+    position: absolute;
+    display: flex;
+    flex-direction: column;
+    padding: var(--space-1) var(--space-2);
+    background: var(--bg);
+    border: var(--border);
+    font-size: var(--font-sm);
+    white-space: nowrap;
+    pointer-events: none;
+}
+.fitness-tip[hidden] { display: none; }
 
 /* === Responsive === */
 @media (max-width: 1100px) {

calendar.go

@@ -646,6 +646,20 @@ func calendarDayLines(from, to time.Time) map[string]calDayLines {
 		}
 	}
 
+	for key, w := range calendarWeights(s, from, to) {
+		lines := out[key]
+		lines.Weight = strings.ReplaceAll(w, ".", ",") + " kg"
+		out[key] = lines
+	}
+	return out
+}
+
+// calendarWeights reads the weight role for [from, to): one entry per day,
+// keyed by "YYYY-MM-DD", holding the kg value with a '.' decimal separator.
+// Events whose title is not a weight are skipped; several entries on one day:
+// the last edited one wins.
+func calendarWeights(s calendarSettings, from, to time.Time) map[string]string {
+	out := map[string]string{}
 	stamps := map[string]time.Time{}
 	for _, ev := range calendarOccurrences(calendarsDir, s.Weight, from, to) {
 		m := weightTitle.FindStringSubmatch(ev.Summary)
@@ -653,14 +667,11 @@ func calendarDayLines(from, to time.Time) map[string]calDayLines {
 			continue
 		}
 		key := ev.Start.Format("2006-01-02")
-		// Several entries on one day: the last edited one wins.
 		if prev, ok := stamps[key]; ok && ev.Stamp.Before(prev) {
 			continue
 		}
 		stamps[key] = ev.Stamp
-		lines := out[key]
+		out[key] = strings.ReplaceAll(m[1], ",", ".")
-		lines.Weight = strings.ReplaceAll(m[1], ".", ",") + " kg"
-		out[key] = lines
 	}
 	return out
 }

fitness.go

@@ -2,14 +2,12 @@ package main
 
 import (
 	"bytes"
-	"encoding/json"
 	"fmt"
 	"html/template"
 	"log"
 	"math"
 	"net/http"
-	"os"
+	"net/url"
-	"path/filepath"
 	"sort"
 	"strconv"
 	"strings"
@@ -20,10 +18,6 @@ func init() {
 	pageTypeHandlers = append(pageTypeHandlers, &fitnessHandler{})
 }
 
-// waistlineExportFile is the exact filename the user copies into the folder.
-// The single file is always the latest export — no glob, no multi-file merge.
-const waistlineExportFile = "waistline_export.json"
-
 type fitnessHandler struct{}
 
 // redirect: the fitness dashboard has no virtual URLs; everything renders
@@ -34,16 +28,15 @@ func (f *fitnessHandler) redirect(root, fsPath, urlPath string, r *http.Request)
 
 // handle renders the dashboard for folders whose .page-settings declares
 // type = fitness. Markdown content and the folder listing stay visible so
-// the user can verify an uploaded export arrived.
+// the folder can still hold notes.
 func (f *fitnessHandler) handle(root, fsPath, urlPath string, r *http.Request) *specialPage {
 	s := readPageSettings(fsPath)
 	if s == nil || s.Type != "fitness" {
 		return nil
 	}
-	weightSel := validFitnessRange(r.URL.Query().Get("weight"), "3m")
+	q := r.URL.Query()
-	weeklySel := validFitnessRange(r.URL.Query().Get("weekly"), "1y")
 	return &specialPage{
-		Content:     renderFitnessDashboard(fsPath, weightSel, weeklySel),
+		Content:     renderFitnessDashboard(fsPath, chartViewFrom(q, "weight", "3m"), chartViewFrom(q, "weekly", "1y")),
 		SuppressTOC: true,
 	}
 }
@@ -72,6 +65,20 @@ func validFitnessRange(v, fallback string) string {
 	return fallback
 }
 
+// fitnessView is one chart's view state from the query string: ?<param>=<range>
+// and ?<param>-absolute=1 to start the y axis at 0.
+type fitnessView struct {
+	Range    string
+	Absolute bool
+}
+
+func chartViewFrom(q url.Values, param, fallback string) fitnessView {
+	return fitnessView{
+		Range:    validFitnessRange(q.Get(param), fallback),
+		Absolute: q.Get(param+"-absolute") == "1",
+	}
+}
+
 func rangeMonths(v string) int {
 	for _, r := range fitnessRanges {
 		if r.Value == v {
@@ -81,95 +88,6 @@ func rangeMonths(v string) int {
 	return 0
 }
 
-// === Waistline export parsing ===
-
-// wlNum is a number in a Waistline export: values appear as JSON numbers,
-// numeric strings, null, or are absent. Unparsable values read as not-ok
-// instead of failing the whole export parse.
-type wlNum struct {
-	val float64
-	ok  bool
-}
-
-func (n *wlNum) UnmarshalJSON(b []byte) error {
-	s := strings.Trim(string(b), `"`)
-	if s == "" || s == "null" {
-		return nil
-	}
-	v, err := strconv.ParseFloat(s, 64)
-	if err != nil {
-		return nil
-	}
-	n.val = v
-	n.ok = true
-	return nil
-}
-
-// Calorie tracking was removed pending a rethink of the (undocumented)
-// per-item formula; only the weight series is read from the export.
-type wlExport struct {
-	Diary    []wlDiaryEntry  `json:"diary"`
-	Settings json.RawMessage `json:"settings"`
-}
-
-type wlDiaryEntry struct {
-	DateTime string `json:"dateTime"`
-	Stats    struct {
-		Weight wlNum `json:"weight"`
-	} `json:"stats"`
-}
-
-// exportDate extracts the calendar day from a Waistline dateTime. The values
-// are UTC-midnight timestamps; taking the first 10 characters avoids time
-// zone conversions shifting the day.
-func exportDate(s string) (time.Time, bool) {
-	if len(s) < 10 {
-		return time.Time{}, false
-	}
-	t, err := time.Parse("2006-01-02", s[:10])
-	if err != nil {
-		return time.Time{}, false
-	}
-	return t, true
-}
-
-// goalValue extracts settings.goals.<key>.goal-list[0].goal[0] — the first
-// weekday slot of the shared goal. Best-effort: any missing or unparsable
-// level means "no goal line", never an error.
-func goalValue(settings json.RawMessage, key string) (float64, bool) {
-	var s struct {
-		Goals map[string]json.RawMessage `json:"goals"`
-	}
-	if json.Unmarshal(settings, &s) != nil {
-		return 0, false
-	}
-	var g struct {
-		GoalList []struct {
-			Goal []wlNum `json:"goal"`
-		} `json:"goal-list"`
-	}
-	if json.Unmarshal(s.Goals[key], &g) != nil {
-		return 0, false
-	}
-	if len(g.GoalList) == 0 || len(g.GoalList[0].Goal) == 0 {
-		return 0, false
-	}
-	n := g.GoalList[0].Goal[0]
-	return n.val, n.ok
-}
-
-func exportWeightUnit(settings json.RawMessage) string {
-	var s struct {
-		Units struct {
-			Weight string `json:"weight"`
-		} `json:"units"`
-	}
-	if json.Unmarshal(settings, &s) == nil && s.Units.Weight != "" {
-		return s.Units.Weight
-	}
-	return "kg"
-}
-
 // === Series extraction ===
 
 type weightPoint struct {
@@ -178,26 +96,34 @@ type weightPoint struct {
 	days  int // >0: weekly mean over this many measured days
 }
 
-// extractWeights computes the weight series from the export: one point per
+// fitnessWeights reads the whole weight calendar up to today: one point per
-// diary entry with stats.weight. Duplicate dates (shouldn't happen) — last
+// day, sorted by date. Dates are UTC midnights to match the chart's today.
-// one wins.
+func fitnessWeights(today time.Time) []weightPoint {
-func extractWeights(ex *wlExport) []weightPoint {
+	byDay := calendarWeights(readCalendarSettings(calendarsDir), time.Time{}, today.AddDate(0, 0, 1))
-	byDate := map[time.Time]float64{}
+	weights := make([]weightPoint, 0, len(byDay))
-	for _, e := range ex.Diary {
+	for key, w := range byDay {
-		day, ok := exportDate(e.DateTime)
+		d, err := time.Parse("2006-01-02", key)
-		if !ok || !e.Stats.Weight.ok {
+		v, err2 := strconv.ParseFloat(w, 64)
+		if err != nil || err2 != nil {
 			continue
 		}
-		byDate[day] = e.Stats.Weight.val
-	}
-	weights := make([]weightPoint, 0, len(byDate))
-	for d, v := range byDate {
 		weights = append(weights, weightPoint{date: d, value: v})
 	}
 	sort.Slice(weights, func(i, j int) bool { return weights[i].date.Before(weights[j].date) })
 	return weights
 }
 
+// weightGoal reads the optional weight-goal key from the fitness folder's
+// .page-settings.
+func weightGoal(fsPath string) (float64, bool) {
+	v, ok := readSettingsFile(fsPath)["weight-goal"]
+	if !ok {
+		return 0, false
+	}
+	g, err := strconv.ParseFloat(strings.ReplaceAll(strings.TrimSpace(v), ",", "."), 64)
+	return g, err == nil
+}
+
 func mondayOf(t time.Time) time.Time {
 	return t.AddDate(0, 0, -((int(t.Weekday()) + 6) % 7))
 }
@@ -280,8 +206,9 @@ type fitnessTickVM struct {
 	Pos, Label, Anchor string
 }
 
+// fitnessDotVM is one data point; Date and Value feed the hover tooltip.
 type fitnessDotVM struct {
-	X, Y, Title string
+	X, Y, Date, Value string
 }
 
 type fitnessGoalVM struct {
@@ -292,6 +219,7 @@ type fitnessChartVM struct {
 	Title    string
 	Param    string
 	Options  []fitnessOptVM
+	Absolute bool
 	Empty    bool
 
 	ViewW, ViewH               string
@@ -301,6 +229,7 @@ type fitnessChartVM struct {
 	Goal                       *fitnessGoalVM
 	Lines                      []string // polyline points attributes
 	Dots                       []fitnessDotVM
+	Dense                      bool // too many points to draw markers
 }
 
 type fitnessDashVM struct {
@@ -308,13 +237,13 @@ type fitnessDashVM struct {
 	Charts []fitnessChartVM
 }
 
-func newChartVM(title, param, sel string) fitnessChartVM {
+func newChartVM(title, param string, view fitnessView) fitnessChartVM {
 	opts := make([]fitnessOptVM, len(fitnessRanges))
 	for i, r := range fitnessRanges {
-		opts[i] = fitnessOptVM{r.Value, r.Label, r.Value == sel}
+		opts[i] = fitnessOptVM{r.Value, r.Label, r.Value == view.Range}
 	}
 	return fitnessChartVM{
-		Title: title, Param: param, Options: opts,
+		Title: title, Param: param, Options: opts, Absolute: view.Absolute,
 		ViewW: svgNum(chartW), ViewH: svgNum(chartH),
 		PlotX: svgNum(chartLeft), PlotY: svgNum(chartTop),
 		PlotR: svgNum(chartW - chartRight), PlotB: svgNum(chartH - chartBottom),
@@ -323,7 +252,7 @@ func newChartVM(title, param, sel string) fitnessChartVM {
 }
 
 // yTickVMs places gridlines at fixed multiples of step across the y domain
-// (always 5 kg guides on weight charts, regardless of range).
+// (5 kg guides on weight charts, 20 kg when the axis starts at 0).
 func yTickVMs(sc chartScale, step float64) []fitnessTickVM {
 	var out []fitnessTickVM
 	for v := math.Ceil(sc.y0/step) * step; v <= sc.y1+step/1e6; v += step {
@@ -346,12 +275,12 @@ func (vm *fitnessChartVM) setGoal(sc chartScale, goal float64, label string) {
 // buildWeightChart renders a weight line chart. It serves both the per-day
 // series and the weekly-mean series (points carrying days > 0); the line is
 // drawn continuous across days/weeks without a measurement.
-func buildWeightChart(all []weightPoint, goal float64, hasGoal bool, sel, param, title, unit string, today time.Time) fitnessChartVM {
+func buildWeightChart(all []weightPoint, goal float64, hasGoal bool, view fitnessView, param, title, unit string, today time.Time) fitnessChartVM {
-	vm := newChartVM(title, param, sel)
+	vm := newChartVM(title, param, view)
 
 	points := all
 	var x0, x1 time.Time
-	if m := rangeMonths(sel); m > 0 {
+	if m := rangeMonths(view.Range); m > 0 {
 		x0 = today.AddDate(0, -m, 0)
 		points = filterWeights(all, x0)
 		if len(points) == 0 {
@@ -391,21 +320,31 @@ func buildWeightChart(all []weightPoint, goal float64, hasGoal bool, sel, param,
 		pad = 1
 	}
 	sc := chartScale{x0, x1, lo - pad, hi + pad}
+	yStep := 5.0
+	if view.Absolute {
+		sc.y0 = 0
+		sc.y1 = hi + hi*0.05
+		yStep = 20
+	}
 
-	vm.YTicks = yTickVMs(sc, 5)
+	vm.YTicks = yTickVMs(sc, yStep)
-	vm.XTicks = timeXTicks(sc, 4)
+	vm.XTicks = timeXTicks(sc)
 
 	// One continuous polyline through every point in range — days without a
-	// measurement do not break the line. Point markers carry the hover
+	// measurement do not break the line. Every point also gets a marker that
-	// <title>; on dense ranges they are dropped and the bare line stays
+	// feeds the hover tooltip; on dense ranges the markers are hidden and the
-	// legible. A single point in range renders as a dot.
+	// bare line stays legible. A single point in range renders as a dot.
 	dot := func(p weightPoint) fitnessDotVM {
-		label := p.date.Format("2006-01-02") + ": " + svgNum(p.value) + " " + unit
+		d := fitnessDotVM{
-		if p.days > 0 {
+			X: svgNum(sc.x(p.date)), Y: svgNum(sc.y(p.value)),
-			label = fmt.Sprintf("Week of %s: %s %s (%d days)",
+			Date:  p.date.Format("Mon 2006-01-02"),
-				p.date.Format("2006-01-02"), svgNum(p.value), unit, p.days)
+			Value: svgNum(p.value) + " " + unit,
 		}
-		return fitnessDotVM{X: svgNum(sc.x(p.date)), Y: svgNum(sc.y(p.value)), Title: label}
+		if p.days > 0 {
+			d.Date = "Week of " + p.date.Format("2006-01-02")
+			d.Value += fmt.Sprintf(" · %d days", p.days)
+		}
+		return d
 	}
 	if len(points) >= 2 {
 		var b strings.Builder
@@ -419,11 +358,10 @@ func buildWeightChart(all []weightPoint, goal float64, hasGoal bool, sel, param,
 		}
 		vm.Lines = append(vm.Lines, b.String())
 	}
-	if len(points) <= 100 {
 	for _, p := range points {
 		vm.Dots = append(vm.Dots, dot(p))
 	}
-	}
+	vm.Dense = len(points) > 100
 
 	if hasGoal {
 		vm.setGoal(sc, goal, "goal "+svgNum(goal))
@@ -441,24 +379,91 @@ func filterWeights(points []weightPoint, from time.Time) []weightPoint {
 	return out
 }
 
-// timeXTicks places n+1 evenly spaced date labels across a continuous time
+// xTickStep is a calendar-aligned spacing for date labels.
-// axis; the last label is end-anchored so it stays inside the viewBox.
+type xTickStep struct {
-func timeXTicks(sc chartScale, n int) []fitnessTickVM {
+	days, months int
-	span := sc.x1.Sub(sc.x0)
+	label        func(t time.Time, first bool) string
-	var out []fitnessTickVM
-	prev := ""
-	for i := 0; i <= n; i++ {
-		t := sc.x0.Add(time.Duration(float64(span) * float64(i) / float64(n)))
-		label := t.Format("2006-01-02")
-		if label == prev {
-			continue
 }
-		prev = label
+
+var xTickSteps = []xTickStep{
+	{days: 1, label: dayLabel},
+	{days: 7, label: dayLabel},
+	{days: 14, label: dayLabel},
+	{months: 1, label: monthLabel},
+	{months: 3, label: monthLabel},
+	{months: 6, label: monthLabel},
+	{months: 12, label: yearLabel},
+	{months: 24, label: yearLabel},
+	{months: 60, label: yearLabel},
+}
+
+func dayLabel(t time.Time, _ bool) string { return t.Format("2 Jan") }
+
+// monthLabel names the year only where it changes, so a year-long axis
+// reads "Oct 2025, Jan 2026, Apr, Jul".
+func monthLabel(t time.Time, first bool) string {
+	if first || t.Month() == time.January {
+		return t.Format("Jan 2006")
+	}
+	return t.Format("Jan")
+}
+
+func yearLabel(t time.Time, _ bool) string { return t.Format("2006") }
+
+// maxXTicks bounds the label count so labels never collide on the axis.
+const maxXTicks = 5
+
+// timeXTicks labels the time axis at calendar boundaries — days, Mondays,
+// month starts or new years, whichever is the finest step that stays within
+// maxXTicks. Labels near the plot edges are anchored inward so they stay
+// inside the viewBox.
+func timeXTicks(sc chartScale) []fitnessTickVM {
+	var ticks []time.Time
+	var step xTickStep
+	for _, step = range xTickSteps {
+		ticks = alignedTicks(sc.x0, sc.x1, step)
+		if len(ticks) <= maxXTicks {
+			break
+		}
+	}
+	out := make([]fitnessTickVM, 0, len(ticks))
+	for i, t := range ticks {
+		x := sc.x(t)
 		anchor := "middle"
-		if i == n {
+		switch {
+		case x-chartLeft < 24:
+			anchor = "start"
+		case chartW-chartRight-x < 24:
 			anchor = "end"
 		}
-		out = append(out, fitnessTickVM{Pos: svgNum(sc.x(t)), Label: label, Anchor: anchor})
+		out = append(out, fitnessTickVM{Pos: svgNum(x), Label: step.label(t, i == 0), Anchor: anchor})
+	}
+	return out
+}
+
+// alignedTicks lists every boundary of step within [from, to]. Week steps
+// start on Mondays; month and year steps on multiples of the step (Jan/Apr/
+// Jul/Oct for quarters, even years for two-year steps).
+func alignedTicks(from, to time.Time, step xTickStep) []time.Time {
+	var t time.Time
+	if step.days > 0 {
+		t = time.Date(from.Year(), from.Month(), from.Day(), 0, 0, 0, 0, time.UTC)
+		if step.days > 1 {
+			t = mondayOf(t)
+		}
+	} else {
+		months := from.Year()*12 + int(from.Month()) - 1
+		months -= months % step.months
+		t = time.Date(months/12, time.Month(months%12+1), 1, 0, 0, 0, 0, time.UTC)
+	}
+	var out []time.Time
+	for ; !t.After(to); t = t.AddDate(0, step.months, step.days) {
+		if !t.Before(from) {
+			out = append(out, t)
+		}
+		if len(out) > maxXTicks {
+			break
+		}
 	}
 	return out
 }
@@ -467,8 +472,8 @@ func timeXTicks(sc chartScale, n int) []fitnessTickVM {
 
 var fitnessTmpl = template.Must(template.ParseFS(assets, "assets/fitness/main.html"))
 
-func renderFitnessDashboard(fsPath, weightSel, weeklySel string) template.HTML {
+func renderFitnessDashboard(fsPath string, weightView, weeklyView fitnessView) template.HTML {
-	data := buildFitnessDash(fsPath, weightSel, weeklySel, time.Now())
+	data := buildFitnessDash(fsPath, weightView, weeklyView, time.Now())
 	var buf bytes.Buffer
 	if err := fitnessTmpl.Execute(&buf, data); err != nil {
 		log.Printf("fitness template: %v", err)
@@ -477,28 +482,23 @@ func renderFitnessDashboard(fsPath, weightSel, weeklySel string) template.HTML {
 	return template.HTML(buf.String())
 }
 
-// buildFitnessDash reads and parses the export per request — no caching, no
+// buildFitnessDash reads the weight calendar per request (the calendar store
-// indexes. A read or parse failure (including a truncated mid-upload file)
+// caches parsed files). A missing calendar setup becomes an inline notice;
-// becomes an inline notice; the page itself always renders.
+// the page itself always renders.
-func buildFitnessDash(fsPath, weightSel, weeklySel string, now time.Time) fitnessDashVM {
+func buildFitnessDash(fsPath string, weightView, weeklyView fitnessView, now time.Time) fitnessDashVM {
-	raw, err := os.ReadFile(filepath.Join(fsPath, waistlineExportFile))
+	if calendarsDir == "" || len(readCalendarSettings(calendarsDir).Weight) == 0 {
-	if err != nil {
+		return fitnessDashVM{Notice: "No weight calendar configured — set weight = <calendar> in the calendars folder's .page-settings."}
-		return fitnessDashVM{Notice: "No Waistline export found — upload " + waistlineExportFile + " to this folder."}
-	}
-	var ex wlExport
-	if err := json.Unmarshal(raw, &ex); err != nil {
-		return fitnessDashVM{Notice: "Could not read " + waistlineExportFile + ": " + err.Error()}
 	}
 
 	today := time.Date(now.Year(), now.Month(), now.Day(), 0, 0, 0, 0, time.UTC)
-	weights := extractWeights(&ex)
+	weights := fitnessWeights(today)
-	wGoal, hasWGoal := goalValue(ex.Settings, "weight")
+	wGoal, hasWGoal := weightGoal(fsPath)
-	unit := exportWeightUnit(ex.Settings)
+	const unit = "kg"
 
 	return fitnessDashVM{Charts: []fitnessChartVM{
-		buildWeightChart(weights, wGoal, hasWGoal, weightSel,
+		buildWeightChart(weights, wGoal, hasWGoal, weightView,
 			"weight", "Weight ("+unit+")", unit, today),
-		buildWeightChart(weeklyMeanWeights(weights), wGoal, hasWGoal, weeklySel,
+		buildWeightChart(weeklyMeanWeights(weights), wGoal, hasWGoal, weeklyView,
 			"weekly", "Weekly average weight ("+unit+")", unit, today),
 	}}
 }

fitness_test.go

@@ -0,0 +1,76 @@
+package main
+
+import (
+	"os"
+	"strings"
+	"path/filepath"
+	"testing"
+	"time"
+)
+
+func TestFitnessWeights(t *testing.T) {
+	withBerlin(t)
+	dir := t.TempDir()
+	prev := calendarsDir
+	calendarsDir = dir
+	t.Cleanup(func() { calendarsDir = prev })
+
+	if err := os.WriteFile(filepath.Join(dir, ".page-settings"),
+		[]byte("type = calendars\nweight = Gewicht\n"), 0644); err != nil {
+		t.Fatal(err)
+	}
+	writeCal(t, dir, "Gewicht",
+		`UID:1
+		SUMMARY:96 kg
+		DTSTART;VALUE=DATE:20261001`,
+		`UID:2
+		SUMMARY:95,6kg
+		DTSTART;VALUE=DATE:20261003`,
+		`UID:3
+		SUMMARY:not a weight
+		DTSTART;VALUE=DATE:20261004`,
+		`UID:4
+		SUMMARY:90 kg
+		DTSTART;VALUE=DATE:20261010`,
+	)
+
+	today := time.Date(2026, 10, 5, 0, 0, 0, 0, time.UTC)
+	got := fitnessWeights(today)
+	want := []weightPoint{
+		{date: time.Date(2026, 10, 1, 0, 0, 0, 0, time.UTC), value: 96},
+		{date: time.Date(2026, 10, 3, 0, 0, 0, 0, time.UTC), value: 95.6},
+	}
+	if len(got) != len(want) {
+		t.Fatalf("got %+v, want %+v", got, want)
+	}
+	for i := range want {
+		if !got[i].date.Equal(want[i].date) || got[i].value != want[i].value {
+			t.Fatalf("point %d: got %+v, want %+v", i, got[i], want[i])
+		}
+	}
+}
+
+func TestTimeXTicks(t *testing.T) {
+	d := func(y int, m time.Month, day int) time.Time { return time.Date(y, m, day, 0, 0, 0, 0, time.UTC) }
+	for _, c := range []struct {
+		from, to time.Time
+		want     string
+	}{
+		{d(2022, 11, 28), d(2026, 9, 21), "2023 2024 2025 2026"},
+		{d(2025, 9, 27), d(2026, 9, 27), "Oct 2025|Jan 2026|Apr|Jul"},
+		{d(2026, 6, 27), d(2026, 9, 27), "Jul 2026|Aug|Sep"},
+		{d(2026, 8, 27), d(2026, 9, 27), "31 Aug|7 Sep|14 Sep|21 Sep"},
+	} {
+		var got []string
+		for _, tk := range timeXTicks(chartScale{x0: c.from, x1: c.to}) {
+			got = append(got, tk.Label)
+		}
+		sep := " "
+		if strings.Contains(c.want, "|") {
+			sep = "|"
+		}
+		if g := strings.Join(got, sep); g != c.want {
+			t.Errorf("%s..%s: got %q, want %q", c.from.Format("2006-01-02"), c.to.Format("2006-01-02"), g, c.want)
+		}
+	}
+}