more CSV stats

README.md

@@ -43,6 +43,27 @@ Time spent per day:
 
 Note that it accounts correctly for overlapping events.
 
+### Weekly CSV summary
+
+After the daily breakdown, the program prints a CSV table to stdout with one row per ISO week:
+
+```
+week_start,hours_per_week,3week_moving_avg,6week_moving_avg,12week_moving_avg
+2026-05-04,18.00,18.00,13.17,10.83
+2026-05-11,15.50,16.75,14.08,11.38
+2026-05-18,18.50,17.33,14.50,12.17
+2026-05-25,29.50,21.17,17.42,14.00
+2026-06-01,4.50,17.50,17.25,13.96
+```
+
+- **`week_start`** — Monday of the ISO week
+- **`hours_per_week`** — total hours logged that week
+- **`3week_moving_avg`** — rolling average over up to 3 weeks
+- **`6week_moving_avg`** — rolling average over up to 6 weeks
+- **`12week_moving_avg`** — rolling average over up to 12 weeks
+
+This makes it easy to pipe the output into a spreadsheet or plotting tool for trend analysis.
+
 ### Time spent per category
 
 If you provide a configuration file which explains how to group events into

internal/core/span.go

@@ -17,7 +17,7 @@ func newSpan(categories []*Category) *span {
 	return &span{categories: categories, events: make(map[*calendar.Event]CategoryName)}
 }
 
-func (s *span) checkpoint(dayTotals map[civil.Date]time.Duration, categoryTotals map[CategoryName]time.Duration, end time.Time) {
+func (s *span) checkpoint(dayTotals map[civil.Date]time.Duration, categoryTotals map[CategoryName]time.Duration, dayCategoryTotals map[civil.Date]map[CategoryName]time.Duration, end time.Time) {
 	timeSpent := end.Sub(s.start)
 	eventCount := len(s.events)
 	var timePerEvent int64
@@ -27,6 +27,13 @@ func (s *span) checkpoint(dayTotals map[civil.Date]time.Duration, categoryTotals
 	}
 	for _, categoryName := range s.events {
 		categoryTotals[categoryName] += time.Duration(timePerEvent)
+		if eventCount > 0 {
+			day := civil.DateOf(s.start)
+			if dayCategoryTotals[day] == nil {
+				dayCategoryTotals[day] = make(map[CategoryName]time.Duration)
+			}
+			dayCategoryTotals[day][categoryName] += time.Duration(timePerEvent)
+		}
 	}
 	s.start = end
 }

internal/core/totals.go

@@ -38,7 +38,7 @@ type thing struct {
 	newDay *civil.Date
 }
 
-func ComputeTotals(events []*calendar.Event, categories []*Category, location *time.Location) (map[civil.Date]time.Duration, map[CategoryName]time.Duration, []*calendar.Event) {
+func ComputeTotals(events []*calendar.Event, categories []*Category, location *time.Location) (map[civil.Date]time.Duration, map[CategoryName]time.Duration, map[civil.Date]map[CategoryName]time.Duration, []*calendar.Event) {
 	moments := computeTimeline(events, location)
 	return categorizeTime(moments, categories)
 }
@@ -124,17 +124,20 @@ func stretchSpeedyMeetings(evStart, evEnd time.Time) (time.Time, time.Time) {
 	}
 }
 
-// categorizeTime returns three values. A map from civil date to time spent on it,
-// a map from category name to time spent on it, and a slice of unrecognized calendar events.
-func categorizeTime(t *timeline, categories []*Category) (map[civil.Date]time.Duration, map[CategoryName]time.Duration, []*calendar.Event) {
+// categorizeTime returns a map from civil date to time spent on it,
+// a map from category name to time spent on it,
+// a map from civil date to per-category time spent on it,
+// and a slice of unrecognized calendar events.
+func categorizeTime(t *timeline, categories []*Category) (map[civil.Date]time.Duration, map[CategoryName]time.Duration, map[civil.Date]map[CategoryName]time.Duration, []*calendar.Event) {
 	momentTimes := t.sortedMoments()
 	dayTotals := make(map[civil.Date]time.Duration)
 	categoryTotals := make(map[CategoryName]time.Duration)
+	dayCategoryTotals := make(map[civil.Date]map[CategoryName]time.Duration)
 	unrecognized := []*calendar.Event{}
 	currentTasks := newSpan(categories)
 
 	for _, momentTime := range momentTimes {
-		currentTasks.checkpoint(dayTotals, categoryTotals, momentTime)
+		currentTasks.checkpoint(dayTotals, categoryTotals, dayCategoryTotals, momentTime)
 		for _, thing := range t.thingsAt(momentTime) {
 			switch thing.what {
 			case midnight:
@@ -148,5 +151,5 @@ func categorizeTime(t *timeline, categories []*Category) (map[civil.Date]time.Du
 			}
 		}
 	}
-	return dayTotals, categoryTotals, unrecognized
+	return dayTotals, categoryTotals, dayCategoryTotals, unrecognized
 }

internal/core/totals_test.go

@@ -141,7 +141,7 @@ func TestComputeTotals(t *testing.T) {
 	}
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
-			gotTotals, gotCategories, gotUnrecognized := ComputeTotals(tt.args.events, tt.args.categories, time.UTC)
+			gotTotals, gotCategories, _, gotUnrecognized := ComputeTotals(tt.args.events, tt.args.categories, time.UTC)
 			assert.Equal(t, tt.wantTotals, gotTotals)
 			if tt.wantCategories != nil {
 				assert.Equal(t, tt.wantCategories, gotCategories)

main.go

@@ -21,8 +21,10 @@ import (
 	"fmt"
 	"log"
 	"os"
+	"sort"
 	"time"
 
+	"cloud.google.com/go/civil"
 	"github.com/porridge/calendar-stats/internal/config"
 	"github.com/porridge/calendar-stats/internal/core"
 	"github.com/porridge/calendar-stats/internal/flags"
@@ -86,7 +88,7 @@ func main() {
 		log.Fatalf("Could not read config file %q: %s", *configFile, err)
 	}
 
-	unrecognized := analyzeAndPrint(events, categories, *decimalOutput)
+	unrecognized := analyzeAndPrint(events, categories, *decimalOutput, true)
 
 	if *correctionsFileName != "" {
 		err = io.SaveUnrecognized(*correctionsFileName, unrecognized)
@@ -96,8 +98,8 @@ func main() {
 	}
 }
 
-func analyzeAndPrint(events []*calendar.Event, categories []*core.Category, decimalOutput bool) []*calendar.Event {
-	dayTotals, categoryTotals, unrecognized := core.ComputeTotals(events, categories, time.Local)
+func analyzeAndPrint(events []*calendar.Event, categories []*core.Category, decimalOutput bool, weeklyCSV bool) []*calendar.Event {
+	dayTotals, categoryTotals, dayCategoryTotals, unrecognized := core.ComputeTotals(events, categories, time.Local)
 	days := ordererd.KeysOfMap(dayTotals, ordererd.CivilDates)
 	var total time.Duration
 	if len(days) > 0 {
@@ -108,6 +110,9 @@ func analyzeAndPrint(events []*calendar.Event, categories []*core.Category, deci
 		value := formatDayTotal(decimalOutput, dayTotals[day])
 		fmt.Printf("%v: %s\n", day, value)
 	}
+	if weeklyCSV && len(days) > 0 {
+		printWeeklyCSV(days, dayTotals, categories, dayCategoryTotals)
+	}
 	if len(categories) == 0 {
 		return unrecognized
 	}
@@ -181,3 +186,84 @@ func formatDayTotal(decimalOutput bool, d time.Duration) string {
 		return d.String()
 	}
 }
+
+func printWeeklyCSV(days []civil.Date, dayTotals map[civil.Date]time.Duration, categories []*core.Category, dayCategoryTotals map[civil.Date]map[core.CategoryName]time.Duration) {
+	type weekKey struct {
+		year, week int
+	}
+	weekTotals := make(map[weekKey]time.Duration)
+	weekCategoryTotals := make(map[weekKey]map[core.CategoryName]time.Duration)
+	for _, day := range days {
+		t := day.In(time.Local)
+		year, week := t.ISOWeek()
+		k := weekKey{year, week}
+		weekTotals[k] += dayTotals[day]
+		if weekCategoryTotals[k] == nil {
+			weekCategoryTotals[k] = make(map[core.CategoryName]time.Duration)
+		}
+		for catName, dur := range dayCategoryTotals[day] {
+			weekCategoryTotals[k][catName] += dur
+		}
+	}
+
+	weeks := make([]weekKey, 0, len(weekTotals))
+	for k := range weekTotals {
+		weeks = append(weeks, k)
+	}
+	sort.Slice(weeks, func(i, j int) bool {
+		if weeks[i].year != weeks[j].year {
+			return weeks[i].year < weeks[j].year
+		}
+		return weeks[i].week < weeks[j].week
+	})
+
+	movingAvg := func(i, window int) float64 {
+		start := i - window + 1
+		if start < 0 {
+			start = 0
+		}
+		var sum float64
+		for j := start; j <= i; j++ {
+			sum += float64(weekTotals[weeks[j]]) / float64(time.Hour)
+		}
+		return sum / float64(i-start+1)
+	}
+
+	catMovingAvg := func(i, window int, catName core.CategoryName) float64 {
+		start := i - window + 1
+		if start < 0 {
+			start = 0
+		}
+		var sum float64
+		for j := start; j <= i; j++ {
+			sum += float64(weekCategoryTotals[weeks[j]][catName]) / float64(time.Hour)
+		}
+		return sum / float64(i-start+1)
+	}
+
+	header := "week_start,hours_per_week,3week_moving_avg,6week_moving_avg,12week_moving_avg"
+	for _, cat := range categories {
+		name := string(cat.Name)
+		if name == "" {
+			name = "uncategorized"
+		}
+		header += "," + name + "_12week_avg"
+	}
+	fmt.Println("\n" + header)
+
+	for i, wk := range weeks {
+		weekStart := isoweek.StartTime(wk.year, wk.week, time.Local)
+		hours := float64(weekTotals[wk]) / float64(time.Hour)
+		fmt.Printf("%s,%.2f,%.2f,%.2f,%.2f",
+			weekStart.Format("2006-01-02"),
+			hours,
+			movingAvg(i, 3),
+			movingAvg(i, 6),
+			movingAvg(i, 12),
+		)
+		for _, cat := range categories {
+			fmt.Printf(",%.2f", catMovingAvg(i, 12, cat.Name))
+		}
+		fmt.Println()
+	}
+}