Chat autosend, week rollover and ai_runs purge schedules (Feature 20)

shopping_chat_autosend fires at chat_autosend_dow/time for the coming
week and posts its Supply run through SendToChat when a webhook is
stored, list_ready's Chat channel is on and the list exists unsent;
otherwise it logs why (key list_ready:chat:{weekStart}). week_rollover
freezes the previous week at Monday 00:05 through Freeze, judging the
week ended by the fire time. ai_runs_purge calls harness.Purge daily at
03:00 with the fire time less RunRetention. Fake-clock tests cover each.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

internal/shopping/schedule.go

@@ -0,0 +1,129 @@
+package shopping
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"time"
+
+	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/household"
+	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/notify"
+	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/scheduler"
+	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/store"
+)
+
+// RolloverTime is when, every Monday in the household zone, week_rollover
+// freezes the week that has just ended. It is fixed, not a setting.
+const RolloverTime = "00:05"
+
+// Reasons Autosend posts nothing.
+const (
+	AutosendNotConfigured = "no Google Chat webhook is configured"
+	AutosendChatOff       = "list_ready is switched off for Google Chat"
+	AutosendNoList        = "the week has no Supply run"
+	AutosendAlreadySent   = "the Supply run was already sent to Google Chat"
+	AutosendUnconfirmed   = "a send of the Supply run to Google Chat is unconfirmed"
+)
+
+// AutosendKey identifies the automatic send of the Supply run of the week
+// starting weekStart, list_ready:chat:YYYY-MM-DD, in the schedule's logs.
+// The send itself is recorded in the list's sent_to_chat_at.
+func AutosendKey(weekStart store.LocalDate) string {
+	return string(notify.ListReady) + ":" + string(notify.ChannelChat) + ":" + weekStart.String()
+}
+
+// ChatAutosendSchedule is the shopping_chat_autosend schedule: at the
+// household's chat_autosend_dow and chat_autosend_time it sends the Supply
+// run of the coming week, the week after the fire date's, to Google Chat
+// with Autosend. Its period scheduler.WeeklyForNextWeek keys
+// shopping_chat_autosend:YYYY-Www for that week. A send that fails is the
+// period's error and is not retried; the household can still send it from
+// the Supply run.
+func (s *Service) ChatAutosendSchedule() scheduler.Schedule {
+	return scheduler.Schedule{
+		Name: scheduler.ShoppingChatAutosend,
+		Rule: func(settings household.Settings) scheduler.Rule {
+			return scheduler.WeeklyForNextWeek(time.Weekday(settings.ChatAutosendDow), settings.ChatAutosendTime)
+		},
+		Run: func(ctx context.Context, p scheduler.Period) error {
+			skipped, err := s.Autosend(ctx, p.Week)
+			if err != nil {
+				return err
+			}
+			log := s.logger.With("period", p.Key, "key", AutosendKey(p.Week), "week_start", p.Week.String())
+			if skipped != "" {
+				log.InfoContext(ctx, "Supply run not sent to Google Chat: "+skipped)
+				return nil
+			}
+			log.InfoContext(ctx, "Supply run sent to Google Chat")
+			return nil
+		},
+	}
+}
+
+// Autosend sends the Supply run of the week starting weekStart to Google
+// Chat with SendToChat, as the household's send does, when a webhook is
+// stored, list_ready's Google Chat channel is switched on, and the week has
+// a Supply run not yet sent and with no send unconfirmed. Otherwise it
+// posts nothing and returns which of those reasons stopped it; it never
+// resends. A send that fails is SendToChat's error.
+func (s *Service) Autosend(ctx context.Context, weekStart store.LocalDate) (skipped string, err error) {
+	settings, err := s.chat.Get(ctx)
+	if err != nil {
+		return "", fmt.Errorf("shopping: autosend: %w", err)
+	}
+	if settings.URLMasked == nil {
+		return AutosendNotConfigured, nil
+	}
+	on, err := s.notifier.ChannelOn(ctx, notify.ListReady, notify.ChannelChat)
+	if err != nil {
+		return "", fmt.Errorf("shopping: autosend: %w", err)
+	}
+	if !on {
+		return AutosendChatOff, nil
+	}
+	l, err := s.Get(ctx, weekStart)
+	if errors.Is(err, ErrListNotFound) {
+		return AutosendNoList, nil
+	}
+	if err != nil {
+		return "", err
+	}
+	switch {
+	case l.SentToChatAt != nil:
+		return AutosendAlreadySent, nil
+	case l.ChatSendUnconfirmedAt != nil:
+		return AutosendUnconfirmed, nil
+	}
+	if _, err := s.SendToChat(ctx, weekStart, false); err != nil {
+		return "", err
+	}
+	return "", nil
+}
+
+// RolloverSchedule is the week_rollover schedule: every Monday at
+// RolloverTime it freezes the Supply run of the week before the fire
+// date's into the Supply archive with Freeze, the week ending by the fire
+// time. Its period scheduler.Weekly keys week_rollover:YYYY-Www for the
+// fire date's week. A week with no Supply run has nothing to freeze, and
+// the period says so; a freeze that fails is the period's error and is not
+// retried.
+func (s *Service) RolloverSchedule() scheduler.Schedule {
+	return scheduler.Schedule{
+		Name: scheduler.WeekRollover,
+		Rule: func(household.Settings) scheduler.Rule {
+			return scheduler.Weekly(time.Monday, RolloverTime)
+		},
+		Run: func(ctx context.Context, p scheduler.Period) error {
+			y, m, d := p.Week.Date()
+			last := store.LocalDateOf(time.Date(y, m, d-7, 0, 0, 0, 0, time.UTC))
+			err := s.freeze(ctx, last, p.FireAt)
+			if errors.Is(err, ErrListNotFound) {
+				s.logger.InfoContext(ctx, "week rollover froze nothing: the week has no Supply run",
+					"period", p.Key, "week_start", last.String())
+				return nil
+			}
+			return err
+		},
+	}
+}