// Copyright 2026 tamakyi. All rights reserved.
// Use of this source code is governed by a MIT-style
// license that can be found in the LICENSE file.

package honeypot

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

func newTestCredStore(t *testing.T) CredStore {
	t.Helper()
	s, err := NewFileCredStore(t.TempDir())
	if err != nil {
		t.Fatalf("NewFileCredStore: %v", err)
	}
	return s
}

// TestFileCredStoreAppendListFilter 覆盖追加、时间倒序、IP 过滤。
func TestFileCredStoreAppendListFilter(t *testing.T) {
	s := newTestCredStore(t)
	now := time.Now()

	if err := s.Append(CredRecord{Time: now.Add(-2 * time.Hour), IP: "1.2.3.4", Username: "admin", Password: "a"}); err != nil {
		t.Fatalf("Append: %v", err)
	}
	if err := s.Append(CredRecord{Time: now, IP: "5.6.7.8", Username: "root", Password: "b"}); err != nil {
		t.Fatalf("Append: %v", err)
	}

	recs, err := s.ListSince(now.Add(-3*time.Hour), "", 10)
	if err != nil {
		t.Fatalf("ListSince: %v", err)
	}
	if len(recs) != 2 {
		t.Fatalf("记录数 = %d, want 2", len(recs))
	}
	if recs[0].IP != "5.6.7.8" {
		t.Errorf("首条 IP = %q, want 5.6.7.8（应按时间倒序）", recs[0].IP)
	}

	// IP 过滤
	only, err := s.ListSince(now.Add(-3*time.Hour), "1.2.3.4", 10)
	if err != nil {
		t.Fatalf("ListSince(ip): %v", err)
	}
	if len(only) != 1 || only[0].Username != "admin" {
		t.Fatalf("IP 过滤结果 = %+v, want 仅 1 条 admin", only)
	}

	// 时间窗过滤
	recent, err := s.ListSince(now.Add(-time.Minute), "", 10)
	if err != nil {
		t.Fatalf("ListSince(since): %v", err)
	}
	if len(recent) != 1 {
		t.Fatalf("近 1 分钟记录数 = %d, want 1", len(recent))
	}
}

// TestFileCredStoreSkipsCorruptLines 确保半行/坏行不会让整天数据报废。
func TestFileCredStoreSkipsCorruptLines(t *testing.T) {
	dir := t.TempDir()
	s, err := NewFileCredStore(dir)
	if err != nil {
		t.Fatalf("NewFileCredStore: %v", err)
	}
	now := time.Now()
	name := filepath.Join(dir, credFileName(now))
	content := `{"time":"` + now.Format(time.RFC3339Nano) + `","ip":"1.1.1.1","username":"a"}` + "\n" +
		`{这行不是合法 JSON` + "\n" +
		"\n" +
		`{"time":"` + now.Add(time.Second).Format(time.RFC3339Nano) + `","ip":"2.2.2.2","username":"b"}` + "\n"
	if err := os.WriteFile(name, []byte(content), 0o600); err != nil {
		t.Fatal(err)
	}

	recs, err := s.ListSince(now.Add(-time.Minute), "", 10)
	if err != nil {
		t.Fatalf("ListSince: %v", err)
	}
	if len(recs) != 2 {
		t.Fatalf("记录数 = %d, want 2（坏行与空行应被跳过）", len(recs))
	}
}

// TestFileCredStoreTopCredentials 覆盖凭据排行榜的计数与排序。
func TestFileCredStoreTopCredentials(t *testing.T) {
	s := newTestCredStore(t)
	now := time.Now()
	for i := 0; i < 3; i++ {
		if err := s.Append(CredRecord{Time: now, IP: "1.1.1.1", Username: "admin", Password: "a"}); err != nil {
			t.Fatal(err)
		}
	}
	if err := s.Append(CredRecord{Time: now, IP: "2.2.2.2", Username: "root", Password: "b"}); err != nil {
		t.Fatal(err)
	}

	stats, err := s.TopCredentials(now.Add(-time.Hour), 10)
	if err != nil {
		t.Fatalf("TopCredentials: %v", err)
	}
	if len(stats) != 2 {
		t.Fatalf("组合数 = %d, want 2", len(stats))
	}
	if stats[0].Username != "admin" || stats[0].Password != "a" || stats[0].Count != 3 {
		t.Errorf("首位 = %+v, want admin/a ×3", stats[0])
	}
}

// TestFileCredStorePurgeBefore 覆盖按天删文件，且不碰边界当天。
func TestFileCredStorePurgeBefore(t *testing.T) {
	s := newTestCredStore(t)
	now := time.Now()
	for _, d := range []int{-10, -5, 0} {
		if err := s.Append(CredRecord{Time: now.AddDate(0, 0, d), IP: "1.1.1.1"}); err != nil {
			t.Fatal(err)
		}
	}
	files, _, err := s.Size()
	if err != nil {
		t.Fatal(err)
	}
	if files != 3 {
		t.Fatalf("文件数 = %d, want 3（按天分文件）", files)
	}

	removed, err := s.PurgeBefore(now.AddDate(0, 0, -7))
	if err != nil {
		t.Fatalf("PurgeBefore: %v", err)
	}
	if removed != 1 {
		t.Errorf("删除文件数 = %d, want 1（只应删 10 天前那份）", removed)
	}

	files, _, err = s.Size()
	if err != nil {
		t.Fatal(err)
	}
	if files != 2 {
		t.Errorf("剩余文件数 = %d, want 2", files)
	}

	// 剩下的记录仍可读
	recs, err := s.ListSince(now.AddDate(0, 0, -20), "", 10)
	if err != nil {
		t.Fatal(err)
	}
	if len(recs) != 2 {
		t.Errorf("剩余记录数 = %d, want 2", len(recs))
	}
}

// TestFileCredStorePermissions 验证目录 0700 / 文件 0600。
//
// 记录里是明文账号密码，同机其他用户不该能读。Windows 上 os.Chmod 语义不同，
// 跳过该用例（部署环境是 Linux）。
func TestFileCredStorePermissions(t *testing.T) {
	if runtime.GOOS == "windows" {
		t.Skip("Windows 不支持 POSIX 权限位")
	}
	dir := filepath.Join(t.TempDir(), "creds")
	s, err := NewFileCredStore(dir)
	if err != nil {
		t.Fatal(err)
	}
	if err := s.Append(CredRecord{Time: time.Now(), IP: "1.1.1.1", Username: "a"}); err != nil {
		t.Fatal(err)
	}

	di, err := os.Stat(dir)
	if err != nil {
		t.Fatal(err)
	}
	if perm := di.Mode().Perm(); perm != 0o700 {
		t.Errorf("目录权限 = %#o, want 0700", perm)
	}

	files, err := filepath.Glob(filepath.Join(dir, credFilePrefix+"*"+credFileSuffix))
	if err != nil || len(files) != 1 {
		t.Fatalf("凭据文件数 = %d, want 1（%v）", len(files), err)
	}
	fi, err := os.Stat(files[0])
	if err != nil {
		t.Fatal(err)
	}
	if perm := fi.Mode().Perm(); perm != 0o600 {
		t.Errorf("文件权限 = %#o, want 0600", perm)
	}
}

// TestFileCredStoreEmptyDir 验证空目录配置会被明确拒绝。
func TestFileCredStoreEmptyDir(t *testing.T) {
	if _, err := NewFileCredStore("  "); err == nil {
		t.Fatal("空目录应返回错误")
	}
}