mavend: he can pick one by position (V-448)

Read before routing and only when a list is bound: with nothing offered,
"второй" is an ordinary word and keeps routing. No verb reads it back
rather than guessing what to do with it.

cmd/mavend/ordinal.go

@@ -0,0 +1,145 @@
+package main
+
+import (
+	"context"
+	"fmt"
+	"log"
+	"strings"
+	"unicode"
+
+	"github.com/kami/maven/internal/dialogue"
+	"github.com/kami/maven/internal/store"
+)
+
+// Ordinal selection over a list she just read (Vikunja #448).
+//
+// The dialogue session already carried the intent, the slots and the history.
+// What it did not carry was the list: she recited five tasks, he said "второй",
+// and there was nothing for that word to point at, so it routed as a fresh
+// utterance and meant nothing.
+//
+// Candidates are bound when she speaks the list, in the order she spoke it (see
+// tasks.Spoken). Binding afterwards would resolve "второй" against a fresh
+// query, and the list can change between two turns.
+//
+// An ordinal with no verb is read back, not acted on: "второй" names a task, it
+// does not say what to do with it. Acting on the bare word would guess, and a
+// wrong guess here closes work he never finished.
+
+// candidateOrdinals — the words that pick a position, by index. Prefix match,
+// because Russian declines them: "первый", "первую", "первое".
+var candidateOrdinals = []struct {
+	word string
+	nth  int
+}{
+	{"перв", 1}, {"втор", 2}, {"трет", 3}, {"четв", 4}, {"пят", 5},
+	{"first", 1}, {"second", 2}, {"third", 3},
+}
+
+// candidateDigits — "второй" said as a number. Matched whole, never by prefix:
+// "15" starts with "1" and is a time, not a position.
+var candidateDigits = map[string]int{"1": 1, "2": 2, "3": 3, "4": 4, "5": 5}
+
+// candidateLast — "последний" picks the end of the list whatever its length.
+var candidateLast = []string{"последн", "last"}
+
+// parseOrdinal reads which position he named. 0 and false when he named none.
+// A negative result means the last one.
+func parseOrdinal(text string) (int, bool) {
+	// Token by token, not substring: " 1" would otherwise match inside
+	// "напомни в 15:00" and turn a reminder into a selection.
+	for _, tok := range strings.FieldsFunc(strings.ToLower(text), func(r rune) bool {
+		return !unicode.IsLetter(r) && !unicode.IsDigit(r)
+	}) {
+		for _, w := range candidateLast {
+			if strings.HasPrefix(tok, w) {
+				return -1, true
+			}
+		}
+		if n, ok := candidateDigits[tok]; ok {
+			return n, true
+		}
+		for _, o := range candidateOrdinals {
+			// Prefix, because Russian declines them: "первый", "первую".
+			if strings.HasPrefix(tok, o.word) {
+				return o.nth, true
+			}
+		}
+	}
+	return 0, false
+}
+
+// candidateVerbs — what he wants done with the one he picked. Nothing here is
+// destructive: a task moves forward or is dropped, and both are recorded with a
+// provenance the /tasks page shows.
+var candidateVerbs = []struct {
+	words  []string
+	status string
+	say    string
+}{
+	{[]string{"готов", "сделал", "выполнил", "закрыл", "done"}, store.TaskDone, "закрыла"},
+	{[]string{"не надо", "убери", "отмени", "не буду", "drop"}, store.TaskDropped, "убрала"},
+	{[]string{"подтвержда", "беру", "да,", "буду делать"}, store.TaskOpen, "взяла в работу"},
+}
+
+func parseCandidateVerb(text string) (status, say string, ok bool) {
+	s := strings.ToLower(strings.TrimSpace(text))
+	for _, v := range candidateVerbs {
+		for _, w := range v.words {
+			if strings.Contains(s, w) {
+				return v.status, v.say, true
+			}
+		}
+	}
+	return "", "", false
+}
+
+// offerCandidates records the list she just read, so his next words can pick
+// from it. Best effort: no session store, or a session that expired between the
+// question and the answer, means the words route normally.
+func (h *reactiveHandler) offerCandidates(cands []dialogue.Candidate) {
+	if h.dialogueSessions == nil || len(cands) == 0 {
+		return
+	}
+	h.dialogueSessions.SetCandidates(voiceDialogueID, h.now(), cands)
+}
+
+// resolveCandidate handles "второй", "первую сделал", "последнюю убери" against
+// the list she just read.
+func (h *reactiveHandler) resolveCandidate(ctx context.Context, text string) (string, bool) {
+	if h.dialogueSessions == nil {
+		return "", false
+	}
+	sess := h.dialogueSessions.Get(voiceDialogueID, h.now())
+	if sess == nil || len(sess.Candidates) == 0 {
+		return "", false
+	}
+	nth, ok := parseOrdinal(text)
+	if !ok {
+		return "", false
+	}
+	if nth < 0 {
+		nth = len(sess.Candidates)
+	}
+	if nth > len(sess.Candidates) {
+		// Claim the turn: he is picking from her list and named a position she
+		// did not read. Routing it fresh would answer something else entirely.
+		return fmt.Sprintf("я назвала только %d.", len(sess.Candidates)), true
+	}
+	pick := sess.Candidates[nth-1]
+	status, say, hasVerb := parseCandidateVerb(text)
+	if !hasVerb || pick.Kind != "task" {
+		// Read it back and keep the list: naming one is often the first half of
+		// a sentence, and the second half is the next turn.
+		return pick.Label, true
+	}
+	if err := h.api.SetTaskStatus(ctx, pick.Ref, status, h.now(), "tap:voice"); err != nil {
+		log.Printf("voice: candidate %d → %s: %v", pick.Ref, status, err)
+		return "не получилось изменить задачу.", true
+	}
+	// Spent: the list she read is no longer the list, and a second ordinal
+	// against it would close the wrong task.
+	h.dialogueSessions.SetCandidates(voiceDialogueID, h.now(), nil)
+	log.Printf("voice: candidate %d (%q) → %s", pick.Ref, pick.Label, status)
+	return say + ": " + pick.Label, true
+}