package main

import (
	"os"
	"path/filepath"
	"testing"
	"time"
)

func TestIsCacheEntryExpired(t *testing.T) {
	if isCacheEntryExpired(time.Now().Add(-24*time.Hour), 0) {
		t.Fatalf("expected ttl=0 to disable expiration")
	}

	if !isCacheEntryExpired(time.Now().Add(-2*time.Hour), time.Hour) {
		t.Fatalf("expected entry to be expired")
	}

	if isCacheEntryExpired(time.Now().Add(-30*time.Minute), time.Hour) {
		t.Fatalf("expected entry to be unexpired")
	}
}

func TestIsTrackedAsNoLyricsHonorsTTLAndPrunes(t *testing.T) {
	cache := &NoLyricsCache{Tracks: map[string]time.Time{
		"old-track":    time.Now().Add(-2 * time.Hour),
		"recent-track": time.Now().Add(-5 * time.Minute),
	}}

	if cache.IsTrackedAsNoLyrics("old-track", time.Hour) {
		t.Fatalf("expected old track to be treated as expired")
	}

	if _, exists := cache.Tracks["old-track"]; exists {
		t.Fatalf("expected expired track to be pruned")
	}

	if !cache.IsTrackedAsNoLyrics("recent-track", time.Hour) {
		t.Fatalf("expected recent track to remain cached")
	}
}

func TestParseRetryAfter(t *testing.T) {
	if got := parseRetryAfter("7"); got != 7*time.Second {
		t.Fatalf("expected 7s, got %s", got)
	}

	future := time.Now().Add(3 * time.Second).UTC().Format(time.RFC1123)
	got := parseRetryAfter(future)
	if got <= 0 || got > 3*time.Second {
		t.Fatalf("expected duration in (0s, 3s], got %s", got)
	}
}

func TestWriteFileAtomically(t *testing.T) {
	dir := t.TempDir()
	target := filepath.Join(dir, "cache.json")
	content := []byte("{\"track\":\"value\"}")

	if err := writeFileAtomically(target, content, 0644); err != nil {
		t.Fatalf("writeFileAtomically failed: %v", err)
	}

	got, err := os.ReadFile(target)
	if err != nil {
		t.Fatalf("failed to read target file: %v", err)
	}

	if string(got) != string(content) {
		t.Fatalf("unexpected content: %q", string(got))
	}
}