Maven/internal/pattern/detector_test.go

package pattern

import (
	"testing"
	"time"
)

func TestDetectEnoughEvents(t *testing.T) {
	// 3 events with 7-day intervals → stable pattern
	base := time.Date(2026, 7, 1, 12, 0, 0, 0, time.UTC)
	events := []Event{
		{Action: "refill", Object: "cat_water", Ts: base},
		{Action: "refill", Object: "cat_water", Ts: base.Add(7 * 24 * time.Hour)},
		{Action: "refill", Object: "cat_water", Ts: base.Add(14 * 24 * time.Hour)},
	}

	r, err := Detect(events)
	if err != nil {
		t.Fatalf("Detect: %v", err)
	}
	if r == nil {
		t.Fatal("want a proposed routine, got nil")
	}
	if r.Action != "refill" || r.Object != "cat_water" {
		t.Fatalf("action/object: want refill/cat_water, got %s/%s", r.Action, r.Object)
	}
	if r.N != 3 {
		t.Fatalf("want N=3, got %d", r.N)
	}
	// ~7 days
	if r.IntervalDays < 6.9 || r.IntervalDays > 7.1 {
		t.Fatalf("want interval ~7, got %f", r.IntervalDays)
	}
}

func TestDetectNotEnoughEvents(t *testing.T) {
	base := time.Date(2026, 7, 1, 12, 0, 0, 0, time.UTC)
	events := []Event{
		{Action: "refill", Object: "cat_water", Ts: base},
		{Action: "refill", Object: "cat_water", Ts: base.Add(7 * 24 * time.Hour)},
	}

	r, err := Detect(events)
	if err != nil {
		t.Fatalf("Detect: %v", err)
	}
	if r != nil {
		t.Fatal("want nil for <3 events")
	}
}

func TestDetectEmpty(t *testing.T) {
	r, err := Detect(nil)
	if err != nil {
		t.Fatalf("Detect: %v", err)
	}
	if r != nil {
		t.Fatal("want nil for empty events")
	}

	r, err = Detect([]Event{})
	if err != nil {
		t.Fatalf("Detect: %v", err)
	}
	if r != nil {
		t.Fatal("want nil for empty events")
	}
}

func TestDetectIrregularRejects(t *testing.T) {
	// 3 events but wildly irregular: 1 day, then 14 days → ratio 14 > 1.5
	base := time.Date(2026, 7, 1, 12, 0, 0, 0, time.UTC)
	events := []Event{
		{Action: "refill", Object: "cat_water", Ts: base},
		{Action: "refill", Object: "cat_water", Ts: base.Add(1 * 24 * time.Hour)},
		{Action: "refill", Object: "cat_water", Ts: base.Add(15 * 24 * time.Hour)},
	}

	r, err := Detect(events)
	if err != nil {
		t.Fatalf("Detect: %v", err)
	}
	if r != nil {
		t.Fatal("want nil for irregular intervals (ratio 14 > 1.5)")
	}
}

func TestDetectBarelyStable(t *testing.T) {
	// 4 events, intervals vary but within 1.5 ratio
	base := time.Date(2026, 7, 1, 12, 0, 0, 0, time.UTC)
	events := []Event{
		{Action: "feed", Object: "cat", Ts: base},
		{Action: "feed", Object: "cat", Ts: base.Add(6 * 24 * time.Hour)},  // 6 days
		{Action: "feed", Object: "cat", Ts: base.Add(12 * 24 * time.Hour)}, // 6 days
		{Action: "feed", Object: "cat", Ts: base.Add(20 * 24 * time.Hour)}, // 8 days
	}

	r, err := Detect(events)
	if err != nil {
		t.Fatalf("Detect: %v", err)
	}
	if r == nil {
		t.Fatal("want proposed routine for barely stable intervals (8/6=1.33 ≤ 1.5)")
	}
	if r.Action != "feed" || r.Object != "cat" {
		t.Fatalf("action/object mismatch")
	}
	if r.N != 4 {
		t.Fatalf("want N=4, got %d", r.N)
	}
}

func TestDetectSameTimestamp(t *testing.T) {
	// Two events at the same time — meaningless interval, should be ignored
	base := time.Date(2026, 7, 1, 12, 0, 0, 0, time.UTC)
	events := []Event{
		{Action: "refill", Object: "cat_water", Ts: base},
		{Action: "refill", Object: "cat_water", Ts: base},
		{Action: "refill", Object: "cat_water", Ts: base.Add(7 * 24 * time.Hour)},
	}

	r, err := Detect(events)
	if err != nil {
		t.Fatalf("Detect: %v", err)
	}
	if r != nil {
		t.Fatal("want nil when first two events have same timestamp")
	}
}

func TestPhraseRoutine(t *testing.T) {
	tests := []struct {
		r    ProposedRoutine
		want string
	}{
		{ProposedRoutine{Action: "refill", Object: "cat_water", IntervalDays: 7}, "ты заправляешь cat water раз в неделю — напоминать?"},
		{ProposedRoutine{Action: "feed", Object: "cat", IntervalDays: 1}, "ты кормишь cat каждый день — напоминать?"},
		{ProposedRoutine{Action: "clean", Object: "litter_box", IntervalDays: 3}, "ты чистишь litter box раз в 3 дня — напоминать?"},
		{ProposedRoutine{Action: "take", Object: "medicine", IntervalDays: 0.5}, "ты принимаешь medicine каждый день — напоминать?"},
		{ProposedRoutine{Action: "walk", Object: "dog", IntervalDays: 14}, "ты выгуливаешь dog раз в 2 недели — напоминать?"},
	}

	for _, tc := range tests {
		t.Run(tc.r.Action+"_"+tc.r.Object, func(t *testing.T) {
			got := PhraseRoutine(&tc.r)
			if got != tc.want {
				t.Fatalf("phrase: want %q, got %q", tc.want, got)
			}
		})
	}
}