feat: reschedule tasks from widget bottom sheet

Tapping a doot task shows a date picker. On confirm, POSTs to
/api/widget/reschedule, updates due_date in native_tasks, refreshes
widget. Reschedule button only shows for source="doot" tasks.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

1 files changed, 31 insertions, 0 deletions

diff --git a/internal/handlers/widget.go b/internal/handlers/widget.go
index 360ccc5..ee13dc4 100644
--- a/internal/handlers/widget.go
+++ b/internal/handlers/widget.go
@@ -101,6 +101,37 @@ type widgetCompleteRequest struct {
 	Source string `json:"source"`
 }
 
+type widgetRescheduleRequest struct {
+	ID     string `json:"id"`
+	Source string `json:"source"`
+	Date   string `json:"date"` // YYYY-MM-DD
+}
+
+// HandleWidgetReschedule updates the due date of a native task.
+func (h *Handler) HandleWidgetReschedule(w http.ResponseWriter, r *http.Request) {
+	var req widgetRescheduleRequest
+	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
+		http.Error(w, "bad request", http.StatusBadRequest)
+		return
+	}
+	if req.Source != "doot" {
+		http.Error(w, "only doot tasks can be rescheduled via widget", http.StatusBadRequest)
+		return
+	}
+	parsed, err := time.Parse("2006-01-02", req.Date)
+	if err != nil {
+		http.Error(w, "invalid date", http.StatusBadRequest)
+		return
+	}
+	tz := config.GetDisplayTimezone()
+	dueDate := time.Date(parsed.Year(), parsed.Month(), parsed.Day(), 0, 0, 0, 0, tz)
+	if err := h.store.RescheduleNativeTask(req.ID, dueDate); err != nil {
+		http.Error(w, "failed to reschedule", http.StatusInternalServerError)
+		return
+	}
+	w.WriteHeader(http.StatusOK)
+}
+
 // HandleWidgetComplete proxies a task completion to the source API or native store.
 func (h *Handler) HandleWidgetComplete(w http.ResponseWriter, r *http.Request) {
 	var req widgetCompleteRequest