package app

import (
	"testing"
	"time"
)

func TestRefreshCoordinatorLifecycle(t *testing.T) {
	now := time.Date(2026, time.March, 9, 21, 0, 0, 0, time.UTC)
	rc := newRefreshCoordinator(10*time.Minute, 2*time.Second, 60*time.Second)

	if !rc.shouldRefresh(now, false, false) {
		t.Fatalf("expected refresh when cache is empty")
	}
	if !rc.beginRefresh(now, false, false) {
		t.Fatalf("expected beginRefresh=true for empty cache")
	}
	if rc.shouldRefresh(now, false, false) {
		t.Fatalf("must not refresh while refresh is in progress")
	}

	rc.finishSuccess(now)
	snap := rc.snapshot(now)
	if snap.RefreshInProgress {
		t.Fatalf("refresh must be finished after success")
	}
	if snap.Stale {
		t.Fatalf("fresh snapshot must not be stale")
	}
	if snap.LastError != "" || snap.NextRetryAt != "" {
		t.Fatalf("success must clear error and retry metadata: %#v", snap)
	}

	if rc.shouldRefresh(now.Add(5*time.Minute), false, true) {
		t.Fatalf("fresh cache should not refresh yet")
	}
	if !rc.shouldRefresh(now.Add(11*time.Minute), false, true) {
		t.Fatalf("stale cache should refresh")
	}
}

func TestRefreshCoordinatorBackoffAndReset(t *testing.T) {
	start := time.Date(2026, time.March, 9, 21, 5, 0, 0, time.UTC)
	rc := newRefreshCoordinator(10*time.Minute, 2*time.Second, 60*time.Second)

	type step struct {
		at       time.Time
		expected time.Duration
	}
	steps := []step{
		{at: start, expected: 2 * time.Second},
		{at: start.Add(2 * time.Second), expected: 4 * time.Second},
		{at: start.Add(6 * time.Second), expected: 8 * time.Second},
		{at: start.Add(14 * time.Second), expected: 16 * time.Second},
		{at: start.Add(30 * time.Second), expected: 32 * time.Second},
		{at: start.Add(62 * time.Second), expected: 60 * time.Second},
	}

	for i, st := range steps {
		rc.finishError("probe failed", st.at)
		got := rc.nextRetryAt().Sub(st.at)
		if got != st.expected {
			t.Fatalf("step=%d unexpected backoff: got=%s want=%s", i+1, got, st.expected)
		}
		if rc.lastError() == "" {
			t.Fatalf("step=%d expected non-empty lastError", i+1)
		}
	}

	rc.finishSuccess(start.Add(2 * time.Minute))
	if rc.consecutiveErrors() != 0 {
		t.Fatalf("expected consecutiveErrors reset, got %d", rc.consecutiveErrors())
	}
	if !rc.nextRetryAt().IsZero() {
		t.Fatalf("expected nextRetryAt reset")
	}
	if rc.lastError() != "" {
		t.Fatalf("expected lastError reset, got %q", rc.lastError())
	}
}