// SPDX-License-Identifier: GPL-3.0-or-later

package health

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

func TestHeartbeatRoundTripAndPermissions(t *testing.T) {
	directory := filepath.Join(t.TempDir(), "state")
	want := time.Unix(1_753_012_345, 987_654_321)
	if err := WriteHeartbeat(directory, want); err != nil {
		t.Fatal(err)
	}
	got, err := ReadHeartbeat(directory)
	if err != nil {
		t.Fatal(err)
	}
	if !got.Equal(time.Unix(want.Unix(), 0)) {
		t.Fatalf("heartbeat=%s want=%s", got, want)
	}
	info, err := os.Stat(filepath.Join(directory, Filename))
	if err != nil {
		t.Fatal(err)
	}
	if got := info.Mode().Perm(); got != 0o600 {
		t.Fatalf("mode=%#o", got)
	}
	if _, err := os.Stat(filepath.Join(directory, Filename+".tmp")); !os.IsNotExist(err) {
		t.Fatalf("temporary heartbeat remains: %v", err)
	}
}

func TestHeartbeatRejectsMissingDirectory(t *testing.T) {
	if err := WriteHeartbeat("", time.Now()); err == nil {
		t.Fatal("empty directory accepted")
	}
}

func TestReadHeartbeatRejectsInvalidContent(t *testing.T) {
	directory := t.TempDir()
	if err := os.WriteFile(filepath.Join(directory, Filename), []byte("invalid\n"), 0o600); err != nil {
		t.Fatal(err)
	}
	if _, err := ReadHeartbeat(directory); err == nil {
		t.Fatal("invalid heartbeat accepted")
	}
}

func TestCheckReportsFreshStaleAndMissing(t *testing.T) {
	directory := t.TempDir()
	now := time.Unix(2_000, 0)
	if err := WriteHeartbeat(directory, now.Add(-30*time.Second)); err != nil {
		t.Fatal(err)
	}
	fresh := Check(directory, now, time.Minute)
	if !fresh.Healthy || fresh.AgeSeconds != 30 || fresh.Detail != "heartbeat is fresh" {
		t.Fatalf("fresh=%#v", fresh)
	}
	stale := Check(directory, now, 10*time.Second)
	if stale.Healthy || stale.Detail != "heartbeat is stale" || stale.MaxAgeSeconds != 10 {
		t.Fatalf("stale=%#v", stale)
	}
	missing := Check(filepath.Join(directory, "missing"), now, time.Minute)
	if missing.Healthy || missing.Detail == "" {
		t.Fatalf("missing=%#v", missing)
	}
}