package main

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

func closeStore(t *testing.T, s *store) {
	t.Helper()
	if err := s.close(); err != nil && !errors.Is(err, os.ErrClosed) {
		t.Error(err)
	}
}

func TestCheckpoint(t *testing.T) {
	path := filepath.Join(t.TempDir(), "state.json")
	s, err := openStore(path)
	if err != nil {
		t.Fatal(err)
	}
	w := failedWatch()
	w.Due = time.Now().Add(time.Minute).UTC()
	w.Failures = 3
	s.Watches["thread-1"] = w
	if err := s.save(); err != nil {
		t.Fatal(err)
	}
	if other, err := openStore(path); err == nil {
		closeStore(t, other)
		t.Fatal("two operators acquired one checkpoint")
	}
	closeStore(t, s)
	restored, err := openStore(path)
	if err != nil {
		t.Fatal(err)
	}
	defer closeStore(t, restored)
	r := restored.watch("thread-1")
	if !r.eligible() || !r.Due.Equal(w.Due) || r.Failures != 3 {
		t.Fatalf("lost recovery: %+v", r)
	}
	info, err := os.Stat(path)
	if err != nil {
		t.Fatal(err)
	}
	if info.Mode().Perm() != 0600 {
		t.Fatal(info.Mode())
	}
}

func TestBadCheckpoint(t *testing.T) {
	path := filepath.Join(t.TempDir(), "state.json")
	if err := os.WriteFile(path, []byte(`{"watches":`), 0600); err != nil {
		t.Fatal(err)
	}
	if s, err := openStore(path); err == nil {
		closeStore(t, s)
		t.Fatal("ignored corrupt state")
	}
}