package service

import (
	"context"
	"strings"
	"testing"

	"gcy_hpc_server/internal/model"
	"gcy_hpc_server/internal/store"

	"go.uber.org/zap"
	gormlogger "gorm.io/gorm/logger"

	"gorm.io/driver/sqlite"
	"gorm.io/gorm"
)

func setupFolderService(t *testing.T) *FolderService {
	t.Helper()
	db, err := gorm.Open(sqlite.Open(":memory:"), &gorm.Config{
		Logger: gormlogger.Default.LogMode(gormlogger.Silent),
	})
	if err != nil {
		t.Fatalf("open sqlite: %v", err)
	}
	if err := db.AutoMigrate(&model.Folder{}, &model.File{}); err != nil {
		t.Fatalf("auto migrate: %v", err)
	}
	return NewFolderService(
		store.NewFolderStore(db),
		store.NewFileStore(db),
		zap.NewNop(),
	)
}

func TestCreateFolder_ValidName(t *testing.T) {
	svc := setupFolderService(t)
	resp, err := svc.CreateFolder(context.Background(), "datasets", nil)
	if err != nil {
		t.Fatalf("CreateFolder() error = %v", err)
	}
	if resp.Name != "datasets" {
		t.Errorf("Name = %q, want %q", resp.Name, "datasets")
	}
	if resp.Path != "/datasets/" {
		t.Errorf("Path = %q, want %q", resp.Path, "/datasets/")
	}
	if resp.ParentID != nil {
		t.Errorf("ParentID should be nil for root folder, got %d", *resp.ParentID)
	}
}

func TestCreateFolder_SubFolder(t *testing.T) {
	svc := setupFolderService(t)
	parent, err := svc.CreateFolder(context.Background(), "datasets", nil)
	if err != nil {
		t.Fatalf("create parent: %v", err)
	}

	child, err := svc.CreateFolder(context.Background(), "images", &parent.ID)
	if err != nil {
		t.Fatalf("CreateFolder() error = %v", err)
	}
	if child.Path != "/datasets/images/" {
		t.Errorf("Path = %q, want %q", child.Path, "/datasets/images/")
	}
	if child.ParentID == nil || *child.ParentID != parent.ID {
		t.Errorf("ParentID = %v, want %d", child.ParentID, parent.ID)
	}
}

func TestCreateFolder_RejectPathTraversal(t *testing.T) {
	svc := setupFolderService(t)
	for _, name := range []string{"..", "../etc", "/absolute", "a/b"} {
		_, err := svc.CreateFolder(context.Background(), name, nil)
		if err == nil {
			t.Errorf("expected error for folder name %q, got nil", name)
		}
	}
}

func TestCreateFolder_DuplicatePath(t *testing.T) {
	svc := setupFolderService(t)
	_, err := svc.CreateFolder(context.Background(), "datasets", nil)
	if err != nil {
		t.Fatalf("first create: %v", err)
	}
	_, err = svc.CreateFolder(context.Background(), "datasets", nil)
	if err == nil {
		t.Fatal("expected error for duplicate folder name")
	}
	if !strings.Contains(err.Error(), "already exists") {
		t.Errorf("error should mention 'already exists', got: %v", err)
	}
}

func TestCreateFolder_ParentNotFound(t *testing.T) {
	svc := setupFolderService(t)
	badID := int64(99999)
	_, err := svc.CreateFolder(context.Background(), "orphan", &badID)
	if err == nil {
		t.Fatal("expected error for non-existent parent")
	}
	if !strings.Contains(err.Error(), "not found") {
		t.Errorf("error should mention 'not found', got: %v", err)
	}
}

func TestGetFolder(t *testing.T) {
	svc := setupFolderService(t)
	created, err := svc.CreateFolder(context.Background(), "datasets", nil)
	if err != nil {
		t.Fatalf("CreateFolder() error = %v", err)
	}

	resp, err := svc.GetFolder(context.Background(), created.ID)
	if err != nil {
		t.Fatalf("GetFolder() error = %v", err)
	}
	if resp.ID != created.ID {
		t.Errorf("ID = %d, want %d", resp.ID, created.ID)
	}
	if resp.Name != "datasets" {
		t.Errorf("Name = %q, want %q", resp.Name, "datasets")
	}
	if resp.FileCount != 0 {
		t.Errorf("FileCount = %d, want 0", resp.FileCount)
	}
	if resp.SubFolderCount != 0 {
		t.Errorf("SubFolderCount = %d, want 0", resp.SubFolderCount)
	}
}

func TestGetFolder_NotFound(t *testing.T) {
	svc := setupFolderService(t)
	_, err := svc.GetFolder(context.Background(), 99999)
	if err == nil {
		t.Fatal("expected error for non-existent folder")
	}
	if !strings.Contains(err.Error(), "not found") {
		t.Errorf("error should mention 'not found', got: %v", err)
	}
}

func TestListFolders(t *testing.T) {
	svc := setupFolderService(t)
	parent, err := svc.CreateFolder(context.Background(), "root", nil)
	if err != nil {
		t.Fatalf("create root: %v", err)
	}
	_, err = svc.CreateFolder(context.Background(), "child1", &parent.ID)
	if err != nil {
		t.Fatalf("create child1: %v", err)
	}
	_, err = svc.CreateFolder(context.Background(), "child2", &parent.ID)
	if err != nil {
		t.Fatalf("create child2: %v", err)
	}

	list, err := svc.ListFolders(context.Background(), &parent.ID)
	if err != nil {
		t.Fatalf("ListFolders() error = %v", err)
	}
	if len(list) != 2 {
		t.Fatalf("len(list) = %d, want 2", len(list))
	}

	names := make(map[string]bool)
	for _, f := range list {
		names[f.Name] = true
	}
	if !names["child1"] || !names["child2"] {
		t.Errorf("expected child1 and child2, got %v", names)
	}
}

func TestListFolders_Root(t *testing.T) {
	svc := setupFolderService(t)
	_, err := svc.CreateFolder(context.Background(), "alpha", nil)
	if err != nil {
		t.Fatalf("create alpha: %v", err)
	}
	_, err = svc.CreateFolder(context.Background(), "beta", nil)
	if err != nil {
		t.Fatalf("create beta: %v", err)
	}

	list, err := svc.ListFolders(context.Background(), nil)
	if err != nil {
		t.Fatalf("ListFolders() error = %v", err)
	}
	if len(list) != 2 {
		t.Errorf("len(list) = %d, want 2", len(list))
	}
}

func TestDeleteFolder_Success(t *testing.T) {
	svc := setupFolderService(t)
	created, err := svc.CreateFolder(context.Background(), "temp", nil)
	if err != nil {
		t.Fatalf("CreateFolder() error = %v", err)
	}
	if err := svc.DeleteFolder(context.Background(), created.ID); err != nil {
		t.Fatalf("DeleteFolder() error = %v", err)
	}
	_, err = svc.GetFolder(context.Background(), created.ID)
	if err == nil {
		t.Error("expected error after deletion")
	}
}

func TestDeleteFolder_NonEmpty(t *testing.T) {
	svc := setupFolderService(t)
	parent, err := svc.CreateFolder(context.Background(), "haschild", nil)
	if err != nil {
		t.Fatalf("create parent: %v", err)
	}
	_, err = svc.CreateFolder(context.Background(), "child", &parent.ID)
	if err != nil {
		t.Fatalf("create child: %v", err)
	}

	err = svc.DeleteFolder(context.Background(), parent.ID)
	if err == nil {
		t.Fatal("expected error when deleting non-empty folder")
	}
	if !strings.Contains(err.Error(), "not empty") {
		t.Errorf("error should mention 'not empty', got: %v", err)
	}
}