package documents

import (
	"bytes"
	"errors"
	"fmt"
	"os"
	"testing"
	"time"

	"github.com/glebarez/sqlite"
	"github.com/stretchr/testify/require"
	"gorm.io/gorm"
	"senlinai-agent/backend/internal/models"
)

func TestDocumentTreeRevisionMoveDeleteAndShareLifecycle(t *testing.T) {
	service, database, user, project := newDocumentTestService(t)

	folder, err := service.CreateFolder(user.ID, project.Identity, CreateInput{Name: "产品"})
	require.NoError(t, err)
	child, err := service.CreateFolder(user.ID, project.Identity, CreateInput{Name: "方案", ParentIdentity: folder.Identity})
	require.NoError(t, err)
	document, err := service.CreateMarkdown(user.ID, project.Identity, CreateInput{
		Name: "说明.md", ParentIdentity: child.Identity, Markdown: "# 第一版",
	})
	require.NoError(t, err)

	loaded, err := service.Get(user.ID, project.Identity, document.Identity)
	require.NoError(t, err)
	require.Equal(t, "# 第一版", loaded.Content.Markdown)
	revision := loaded.Document.Revision
	nextMarkdown := "# 第二版"
	updated, err := service.Update(user.ID, project.Identity, document.Identity, UpdateInput{
		Markdown: &nextMarkdown, Revision: &revision,
	})
	require.NoError(t, err)
	require.Equal(t, revision+1, updated.Document.Revision)

	stale := "# 陈旧覆盖"
	_, err = service.Update(user.ID, project.Identity, document.Identity, UpdateInput{
		Markdown: &stale, Revision: &revision,
	})
	require.ErrorIs(t, err, ErrRevisionConflict)

	parent := child.Identity
	_, err = service.Update(user.ID, project.Identity, folder.Identity, UpdateInput{ParentIdentity: &parent})
	require.ErrorIs(t, err, ErrInvalidParent)

	share, token, err := service.CreateShare(user.ID, project.Identity, document.Identity, 24*time.Hour)
	require.NoError(t, err)
	require.NotEmpty(t, token)
	require.NotEqual(t, token, share.TokenHash)
	shared, err := service.ResolveShare(token)
	require.NoError(t, err)
	require.Equal(t, document.Identity, shared.Document.Identity)
	require.NoError(t, service.RevokeShare(user.ID, project.Identity, document.Identity, share.Identity))
	_, err = service.ResolveShare(token)
	require.ErrorIs(t, err, ErrShareNotFound)

	require.NoError(t, service.Delete(user.ID, project.Identity, folder.Identity))
	var visible int64
	require.NoError(t, database.Model(&models.SaDocumentTree{}).Where("project_id = ?", project.ID).Count(&visible).Error)
	require.Zero(t, visible)
	var retained int64
	require.NoError(t, database.Unscoped().Model(&models.SaDocumentTree{}).Where("project_id = ?", project.ID).Count(&retained).Error)
	require.Equal(t, int64(3), retained)
}

func TestDocumentUploadUsesOpaqueStorageAndMarkdownNamesAreDeduplicated(t *testing.T) {
	service, _, user, project := newDocumentTestService(t)

	first, err := service.CreateMarkdown(user.ID, project.Identity, CreateInput{Name: "记录.md", Markdown: "first"})
	require.NoError(t, err)
	second, err := service.CreateMarkdown(user.ID, project.Identity, CreateInput{Name: "记录.md", Markdown: "second"})
	require.NoError(t, err)
	require.Equal(t, "记录.md", first.Name)
	require.Equal(t, "记录 (1).md", second.Name)

	content := bytes.Repeat([]byte("pdf-content"), 128)
	stored, err := service.Store(project.Identity, "../../合同.pdf", bytes.NewReader(content))
	require.NoError(t, err)
	require.Equal(t, "合同.pdf", stored.OriginalName)
	require.NotContains(t, stored.RelativePath, "合同.pdf")
	require.FileExists(t, stored.AbsolutePath)
	uploaded, err := service.CreateUploaded(user.ID, project.Identity, "", stored)
	require.NoError(t, err)
	require.Equal(t, ".pdf", uploaded.Extension)
	require.Equal(t, int64(len(content)), uploaded.Size)
	file, err := os.Open(stored.AbsolutePath)
	require.NoError(t, err)
	defer file.Close()
}

func TestDocumentExportProducesDownloadableFormats(t *testing.T) {
	service, _, user, project := newDocumentTestService(t)
	document, err := service.CreateMarkdown(user.ID, project.Identity, CreateInput{Name: "导出.md", Markdown: "# 标题\n\n正文"})
	require.NoError(t, err)
	loaded, err := service.Get(user.ID, project.Identity, document.Identity)
	require.NoError(t, err)

	for _, format := range []string{"md", "docx", "pdf"} {
		data, name, contentType, err := service.Export(*loaded, format)
		require.NoError(t, err)
		require.NotEmpty(t, data)
		require.Equal(t, "导出."+format, name)
		require.NotEmpty(t, contentType)
	}
}

func newDocumentTestService(t *testing.T) (*Service, *gorm.DB, models.SaUser, models.SaProject) {
	t.Helper()
	database, err := gorm.Open(sqlite.Open(fmt.Sprintf("file:%s?mode=memory&cache=shared", t.Name())), &gorm.Config{TranslateError: true})
	require.NoError(t, err)
	require.NoError(t, models.AutoMigrate(database))
	user := models.SaUser{Email: t.Name() + "@example.com", DisplayName: "Owner", PasswordHash: "hash"}
	require.NoError(t, database.Create(&user).Error)
	project := models.SaProject{OwnerID: user.ID, Name: "Documents", Identifier: "DOCS-" + fmt.Sprint(time.Now().UnixNano())}
	require.NoError(t, database.Create(&project).Error)
	service := NewService(database, t.TempDir())
	service.now = func() time.Time { return time.Date(2026, 7, 24, 0, 0, 0, 0, time.UTC) }
	t.Cleanup(func() {
		require.False(t, errors.Is(database.Error, gorm.ErrInvalidDB))
	})
	return service, database, user, project
}