package service

import (
	"archive/zip"
	"errors"
	"os"
	"path/filepath"
	"strings"
	"testing"

	"github.com/freefire/jiang13-bbs/model"
	"github.com/glebarez/sqlite"
	"gorm.io/gorm"
	"gorm.io/gorm/logger"
)

// newLegacyTestEnv 建新站内存库 + 旧站 SQLite 文件 + 两个 zip 包，并灌入固定种子数据：
// 用户 alice(#1)/bob(#2)/carol(#3)/dave(#4)，板块 闲聊(#10)，
// 帖子 #100(alice)/#101(bob)/#102(carol 草稿)/#103(alice 投票)/#104(dave)，
// 评论 #200(bob→100)/#201(carol→100)/#202(alice→101)。
func newLegacyTestEnv(t *testing.T) (*LegacyImportService, string, string, string, uint, map[uint]bool) {
	t.Helper()
	tmp := t.TempDir()

	newDB, err := gorm.Open(sqlite.Open(":memory:"), &gorm.Config{Logger: logger.Default.LogMode(logger.Silent)})
	if err != nil {
		t.Fatalf("open new db: %v", err)
	}
	if err := newDB.AutoMigrate(&model.User{}, &model.Board{}, &model.Post{}, &model.Comment{}, &model.ImportRecord{}); err != nil {
		t.Fatalf("migrate new db: %v", err)
	}
	admin := model.User{Username: "admin", Password: "x", Nickname: "站长", Role: model.RoleOwner}
	if err := newDB.Create(&admin).Error; err != nil {
		t.Fatalf("seed admin: %v", err)
	}

	oldPath := filepath.Join(tmp, "old.db")
	oldDB, err := gorm.Open(sqlite.Open(oldPath), &gorm.Config{Logger: logger.Default.LogMode(logger.Silent)})
	if err != nil {
		t.Fatalf("open old db: %v", err)
	}
	if err := oldDB.AutoMigrate(&legacyUserRow{}, &legacyBoardRow{}, &legacyPostRow{}, &legacyCommentRow{}); err != nil {
		t.Fatalf("migrate old db: %v", err)
	}
	seed := []interface{}{
		&legacyUserRow{ID: 1, Username: "alice", Password: "h1", Nickname: "爱丽丝", Avatar: "/uploads/avatars/a1.jpg"},
		&legacyUserRow{ID: 2, Username: "bob", Password: "h2", Nickname: "鲍勃"},
		&legacyUserRow{ID: 3, Username: "carol", Password: "h3", Nickname: "卡罗尔"},
		&legacyUserRow{ID: 4, Username: "dave", Password: "h4"},
		&legacyBoardRow{ID: 10, Name: "闲聊"},
		&legacyPostRow{ID: 100, BoardID: 10, UserID: 1, Title: "看图帖", Status: "published", PostType: "normal",
			Content: `<p>看图</p><p><img src="/uploads/posts/img1.jpg"></p>`},
		&legacyPostRow{ID: 101, BoardID: 10, UserID: 2, Title: "普通帖", Status: "published", PostType: "normal", Content: `<p>正文</p>`},
		&legacyPostRow{ID: 102, BoardID: 10, UserID: 3, Title: "草稿帖", Status: "draft", PostType: "normal", Content: `<p>草稿</p>`},
		&legacyPostRow{ID: 103, BoardID: 10, UserID: 1, Title: "投票帖", Status: "published", PostType: "poll", Content: `<p>投票</p>`},
		&legacyPostRow{ID: 104, BoardID: 10, UserID: 4, Title: "缺图帖", Status: "published", PostType: "normal",
			Content: `<p>缺图</p><p><img src="/uploads/posts/missing.jpg"></p>`},
		&legacyCommentRow{ID: 200, PostID: 100, UserID: 2, Status: "published",
			Content: `<p>补一张</p><p><img src="https://old.example.com/uploads/posts/img1.jpg"></p>`},
		&legacyCommentRow{ID: 201, PostID: 100, UserID: 3, Status: "published", Content: `<p>顶</p>`},
		&legacyCommentRow{ID: 202, PostID: 101, UserID: 1, Status: "published", Content: `<p>前排</p>`},
	}
	for _, row := range seed {
		if err := oldDB.Create(row).Error; err != nil {
			t.Fatalf("seed old db: %v", err)
		}
	}
	// seed 完成即释放句柄，避免 TempDir 清理时文件被占用
	if sqlDB, err := oldDB.DB(); err == nil {
		_ = sqlDB.Close()
	}

	avatarZip := filepath.Join(tmp, "avatars.zip")
	writeTestZip(t, avatarZip, map[string]string{"a1.jpg": "fake-avatar"})
	imagesZip := filepath.Join(tmp, "images.zip")
	writeTestZip(t, imagesZip, map[string]string{"img1.jpg": "fake-image"})

	svc := NewLegacyImportService(newDB, filepath.Join(tmp, "uploads"))
	// 入厅钩子桩：生产为 PostgreSQL，ChatService.EnsureDefaultMembership 里的
	// GREATEST 表达式 SQLite 不支持，故用等价桩验证「建号即触发钩子」的接线
	hallMembers := map[uint]bool{}
	svc.WithHallMembership(func(id uint) error {
		hallMembers[id] = true
		return nil
	})
	return svc, oldPath, avatarZip, imagesZip, admin.ID, hallMembers
}

func writeTestZip(t *testing.T, path string, files map[string]string) {
	t.Helper()
	f, err := os.Create(path)
	if err != nil {
		t.Fatalf("create zip: %v", err)
	}
	w := zip.NewWriter(f)
	for name, content := range files {
		fw, err := w.Create(name)
		if err != nil {
			t.Fatalf("zip entry: %v", err)
		}
		if _, err := fw.Write([]byte(content)); err != nil {
			t.Fatalf("zip write: %v", err)
		}
	}
	if err := w.Close(); err != nil {
		t.Fatalf("zip close: %v", err)
	}
	if err := f.Close(); err != nil {
		t.Fatalf("zip file close: %v", err)
	}
}

func TestLegacyImportPreviewLists(t *testing.T) {
	svc, oldPath, avatarZip, imagesZip, _, _ := newLegacyTestEnv(t)
	rep, err := svc.ImportFromFiles(oldPath, avatarZip, imagesZip, LegacyImportOptions{WithContent: true, DryRun: true}, 1)
	if err != nil {
		t.Fatalf("dry run: %v", err)
	}
	if len(rep.UserList) != 4 || len(rep.PostList) != 5 || len(rep.CommentList) != 3 {
		t.Fatalf("预检清单数量不符: users=%d posts=%d comments=%d", len(rep.UserList), len(rep.PostList), len(rep.CommentList))
	}
	if rep.UserList[0].Username != "alice" || !rep.UserList[0].HasAvatar {
		t.Fatal("alice 预检项不符")
	}
	// 将导入：#100/#101/#104（草稿、投票排除）
	if rep.Posts.Imported != 3 || rep.Posts.PollsSkipped != 1 {
		t.Fatalf("预检帖子统计不符: %+v", rep.Posts)
	}
	// dry-run 不落盘
	if _, err := os.Stat(filepath.Join(svc.uploadsDir, "images", "img1.jpg")); !os.IsNotExist(err) {
		t.Fatal("预检不应写文件")
	}
}

func TestLegacyImportSelectiveRun(t *testing.T) {
	svc, oldPath, avatarZip, imagesZip, adminID, hallMembers := newLegacyTestEnv(t)
	opts := LegacyImportOptions{
		WithContent:     true,
		SkipUserIDs:     map[uint]bool{2: true, 3: true}, // bob / carol 不建号
		UserTargetNames: map[uint]string{2: "admin"},     // bob 的内容归到已有账号 admin
		SkipCommentIDs:  map[uint]bool{202: true},        // 排除 alice 在 #101 的评论
	}
	rep, err := svc.ImportFromFiles(oldPath, avatarZip, imagesZip, opts, adminID)
	if err != nil {
		t.Fatalf("import: %v", err)
	}

	// 用户：alice / dave 建号，bob / carol 排除
	if rep.Users.Imported != 2 || rep.Users.Excluded != 2 {
		t.Fatalf("用户统计不符: %+v", rep.Users)
	}
	// 帖子：#100/#101/#104 导入，#102 草稿跳过，#103 投票
	if rep.Posts.Imported != 3 || rep.Posts.Excluded != 0 || rep.Posts.PollsSkipped != 1 {
		t.Fatalf("帖子统计不符: %+v", rep.Posts)
	}
	// 评论：#200/#201 导入，#202 排除
	if rep.Comments.Imported != 2 || rep.Comments.Excluded != 1 {
		t.Fatalf("评论统计不符: %+v", rep.Comments)
	}
	// 图片：#100 与 #200 各引用 img1.jpg，只落盘一次
	if rep.Posts.ImagesWritten != 1 || len(rep.Comments.ImagesMissing) != 0 {
		t.Fatalf("图片统计不符: posts=%+v comments=%+v", rep.Posts.ImagesWritten, rep.Comments.ImagesMissing)
	}
	if len(rep.Posts.ImagesMissing) != 1 || rep.Posts.ImagesMissing[0] != "missing.jpg" {
		t.Fatalf("缺失图片应记录: %v", rep.Posts.ImagesMissing)
	}

	// 内容归属
	var post100, post101 model.Post
	if err := svc.db.Where("title = ?", "看图帖").First(&post100).Error; err != nil {
		t.Fatalf("post100: %v", err)
	}
	if err := svc.db.Where("title = ?", "普通帖").First(&post101).Error; err != nil {
		t.Fatalf("post101: %v", err)
	}
	var alice model.User
	if err := svc.db.Where("username = ?", "alice").First(&alice).Error; err != nil {
		t.Fatalf("alice: %v", err)
	}
	if post100.UserID != alice.ID {
		t.Fatalf("#100 应归 alice: got %d", post100.UserID)
	}
	if post101.UserID != adminID {
		t.Fatalf("#101 应按 user_map 归 admin: got %d", post101.UserID)
	}

	// bob 的评论 #200 也归 admin；carol 的评论 #201 兜底归 admin
	var cm200, cm201 model.Comment
	if err := svc.db.Where("content LIKE ?", "%补一张%").First(&cm200).Error; err != nil {
		t.Fatalf("cm200: %v", err)
	}
	if err := svc.db.Where("content LIKE ?", "%顶%").First(&cm201).Error; err != nil {
		t.Fatalf("cm201: %v", err)
	}
	if cm200.UserID != adminID || cm201.UserID != adminID {
		t.Fatalf("评论归属不符: cm200=%d cm201=%d", cm200.UserID, cm201.UserID)
	}

	// 图片 URL 改写 + 文件落盘
	if !strings.Contains(post100.Content, legacyImagePrefix+"img1.jpg") || strings.Contains(post100.Content, legacyPostImagePrefix) {
		t.Fatalf("#100 图片 URL 未改写: %s", post100.Content)
	}
	if !strings.Contains(cm200.Content, legacyImagePrefix+"img1.jpg") || strings.Contains(cm200.Content, "old.example.com") {
		t.Fatalf("#200 图片 URL 未改写: %s", cm200.Content)
	}
	// 缺图帖：包内缺失的引用保留原链接，不改写
	p104 := post104Content(t, svc)
	if !strings.Contains(p104, legacyPostImagePrefix+"missing.jpg") || strings.Contains(p104, legacyImagePrefix) {
		t.Fatalf("缺图引用应保留原链接: %s", p104)
	}
	if _, err := os.Stat(filepath.Join(svc.uploadsDir, "images", "img1.jpg")); err != nil {
		t.Fatalf("img1.jpg 未落盘: %v", err)
	}
	if _, err := os.Stat(filepath.Join(svc.uploadsDir, "avatars", "a1.jpg")); err != nil {
		t.Fatalf("头像未落盘: %v", err)
	}

	// 导入建号的用户触发入厅钩子；被排除建号的 bob/carol 不触发
	var dave model.User
	if err := svc.db.Where("username = ?", "dave").First(&dave).Error; err != nil {
		t.Fatalf("dave: %v", err)
	}
	if len(hallMembers) != 2 || !hallMembers[alice.ID] || !hallMembers[dave.ID] {
		t.Fatalf("入厅钩子应只对 alice/dave 触发: %v", hallMembers)
	}

	// 幂等：重复导入全部跳过
	rep2, err := svc.ImportFromFiles(oldPath, avatarZip, imagesZip, opts, adminID)
	if err != nil {
		t.Fatalf("re-import: %v", err)
	}
	if rep2.Users.Imported != 0 || rep2.Posts.Imported != 0 || rep2.Comments.Imported != 0 {
		t.Fatalf("重复导入应全部跳过: %+v", rep2)
	}
	if rep2.Users.Excluded != 2 || rep2.Posts.Skipped != 4 || rep2.Comments.Skipped != 2 {
		t.Fatalf("重复导入统计不符: users=%+v posts=%+v comments=%+v", rep2.Users, rep2.Posts, rep2.Comments)
	}
}

// TestLegacyImportSkipPostCascades 排除帖子时其评论自动跳过
func TestLegacyImportSkipPostCascades(t *testing.T) {
	svc, oldPath, avatarZip, imagesZip, adminID, _ := newLegacyTestEnv(t)
	opts := LegacyImportOptions{
		WithContent: true,
		SkipPostIDs: map[uint]bool{101: true}, // #101 排除 → 其评论 #202 自动跳过
	}
	rep, err := svc.ImportFromFiles(oldPath, avatarZip, imagesZip, opts, adminID)
	if err != nil {
		t.Fatalf("import: %v", err)
	}
	if rep.Posts.Imported != 2 || rep.Posts.Excluded != 1 {
		t.Fatalf("帖子统计不符: %+v", rep.Posts)
	}
	if rep.Comments.Imported != 2 || rep.Comments.Excluded != 1 {
		t.Fatalf("评论统计不符（#202 应随 #101 排除）: %+v", rep.Comments)
	}
	var n int64
	svc.db.Model(&model.Post{}).Where("title = ?", "普通帖").Count(&n)
	if n != 0 {
		t.Fatal("#101 不应导入")
	}
}

// TestLegacyImportBadTarget 归属目标账号不存在时报错
func TestLegacyImportBadTarget(t *testing.T) {
	svc, oldPath, avatarZip, imagesZip, adminID, _ := newLegacyTestEnv(t)
	opts := LegacyImportOptions{WithContent: true, UserTargetNames: map[uint]string{2: "ghost"}}
	_, err := svc.ImportFromFiles(oldPath, avatarZip, imagesZip, opts, adminID)
	if !errors.Is(err, ErrLegacyBadTarget) {
		t.Fatalf("应返回 ErrLegacyBadTarget: %v", err)
	}
}

func post104Content(t *testing.T, svc *LegacyImportService) string {
	t.Helper()
	var p model.Post
	if err := svc.db.Where("title = ?", "缺图帖").First(&p).Error; err != nil {
		t.Fatalf("post104: %v", err)
	}
	return p.Content
}