1 files changed, 83 insertions, 0 deletions
diff --git a/internal/handlers/timeline_multiday_test.go b/internal/handlers/timeline_multiday_test.go
new file mode 100644
index 0000000..3dc2005
--- /dev/null
+++ b/internal/handlers/timeline_multiday_test.go
@@ -0,0 +1,83 @@
+package handlers
+
+import (
+	"testing"
+	"time"
+
+	"task-dashboard/internal/models"
+)
+
+func multiDayEvent(startISO, endISO string) models.TimelineItem {
+	start, _ := time.Parse(time.RFC3339, startISO)
+	end, _ := time.Parse(time.RFC3339, endISO)
+	return models.TimelineItem{
+		ID:      "evt-1",
+		Title:   "Offsite",
+		Type:    models.TimelineItemTypeEvent,
+		Time:    start,
+		EndTime: &end,
+	}
+}
+
+func TestIsMultiDayEvent_SameDayTimedEvent_False(t *testing.T) {
+	item := multiDayEvent("2026-07-13T10:00:00Z", "2026-07-13T11:00:00Z")
+	if isMultiDayEvent(item) {
+		t.Error("expected same-day timed event to not be multi-day")
+	}
+}
+
+func TestIsMultiDayEvent_SpansMultipleDays_True(t *testing.T) {
+	item := multiDayEvent("2026-07-13T17:35:00Z", "2026-07-30T22:30:00Z")
+	if !isMultiDayEvent(item) {
+		t.Error("expected event spanning multiple days to be multi-day")
+	}
+}
+
+func TestIsMultiDayEvent_NonEventType_AlwaysFalse(t *testing.T) {
+	start, _ := time.Parse(time.RFC3339, "2026-07-13T10:00:00Z")
+	end, _ := time.Parse(time.RFC3339, "2026-07-30T22:30:00Z")
+	item := models.TimelineItem{ID: "t1", Type: models.TimelineItemTypeTask, Time: start, EndTime: &end}
+	if isMultiDayEvent(item) {
+		t.Error("expected non-event type to never be considered multi-day, regardless of span")
+	}
+}
+
+func TestIsMultiDayEvent_NoEndTime_False(t *testing.T) {
+	start, _ := time.Parse(time.RFC3339, "2026-07-13T10:00:00Z")
+	item := models.TimelineItem{ID: "e1", Type: models.TimelineItemTypeEvent, Time: start}
+	if isMultiDayEvent(item) {
+		t.Error("expected event with nil EndTime to not be multi-day")
+	}
+}
+
+func TestMultiDayVariant_StartDay_ReturnsStarts(t *testing.T) {
+	item := multiDayEvent("2026-07-13T17:35:00Z", "2026-07-30T22:30:00Z")
+	renderDay, _ := time.Parse(time.RFC3339, "2026-07-13T00:00:00Z")
+	if got := multiDayVariant(item, renderDay); got != "starts" {
+		t.Errorf("variant = %q, want %q", got, "starts")
+	}
+}
+
+func TestMultiDayVariant_EndDay_ReturnsEnds(t *testing.T) {
+	item := multiDayEvent("2026-07-13T17:35:00Z", "2026-07-30T22:30:00Z")
+	renderDay, _ := time.Parse(time.RFC3339, "2026-07-30T00:00:00Z")
+	if got := multiDayVariant(item, renderDay); got != "ends" {
+		t.Errorf("variant = %q, want %q", got, "ends")
+	}
+}
+
+func TestMultiDayVariant_MiddleDay_ReturnsSpans(t *testing.T) {
+	item := multiDayEvent("2026-07-13T17:35:00Z", "2026-07-30T22:30:00Z")
+	renderDay, _ := time.Parse(time.RFC3339, "2026-07-20T00:00:00Z")
+	if got := multiDayVariant(item, renderDay); got != "spans" {
+		t.Errorf("variant = %q, want %q", got, "spans")
+	}
+}
+
+func TestMultiDayVariant_DayOutsideSpan_ReturnsEmpty(t *testing.T) {
+	item := multiDayEvent("2026-07-13T17:35:00Z", "2026-07-30T22:30:00Z")
+	renderDay, _ := time.Parse(time.RFC3339, "2026-08-01T00:00:00Z")
+	if got := multiDayVariant(item, renderDay); got != "" {
+		t.Errorf("variant = %q, want empty", got)
+	}
+}