ttstd-infinite-canvas/backend/internal/app/project.go

package app

import (
	"encoding/json"
	"errors"
	"fmt"
	"net/http"
	"strings"
	"time"

	"yingce/backend/internal/model"
	"yingce/backend/internal/repository"

	"gorm.io/gorm"
)

type CreateProjectRequest struct {
	Name              string `json:"name"`
	Type              string `json:"type"`
	AspectRatio       string `json:"aspectRatio"`
	SourceType        string `json:"sourceType"`
	Description       string `json:"description"`
	StylePresetID     string `json:"stylePresetId"`
	StyleProfileJSON  string `json:"styleProfileJson"`
	DefaultImageModel string `json:"defaultImageModel"`
	DefaultVideoModel string `json:"defaultVideoModel"`
}

type UpdateProjectRequest struct {
	Name              string  `json:"name"`
	Type              string  `json:"type"`
	AspectRatio       string  `json:"aspectRatio"`
	SourceType        string  `json:"sourceType"`
	Description       *string `json:"description"`
	CoverResourceID   *string `json:"coverResourceId"`
	StylePresetID     *string `json:"stylePresetId"`
	StyleProfileJSON  *string `json:"styleProfileJson"`
	DefaultImageModel *string `json:"defaultImageModel"`
	DefaultVideoModel *string `json:"defaultVideoModel"`
	Status            string  `json:"status"`
}

type CreateProjectUnitRequest struct {
	Kind       string `json:"kind"`
	Title      string `json:"title"`
	SourceText string `json:"sourceText"`
	Position   int    `json:"position"`
}

type UpdateProjectUnitRequest struct {
	Title      string `json:"title"`
	SourceText string `json:"sourceText"`
	Status     string `json:"status"`
}

type ImportProjectUnitsRequest struct {
	Units []CreateProjectUnitRequest `json:"units"`
}

type ReorderProjectUnitsRequest struct {
	UnitIDs []string `json:"unitIds"`
}

type LinkCanvasUnitRequest struct {
	CanvasID string `json:"canvasId"`
	UnitID   string `json:"unitId"`
	Role     string `json:"role"`
}

type ProjectSummary struct {
	Project            model.Project `json:"project"`
	CanvasCount        int           `json:"canvasCount"`
	AssetCount         int64         `json:"assetCount"`
	UnitCount          int           `json:"unitCount"`
	CompletedUnitCount int           `json:"completedUnitCount"`
}

type ProjectListPage struct {
	Projects []ProjectSummary `json:"projects"`
	Page     int              `json:"page"`
	PageSize int              `json:"pageSize"`
	Total    int64            `json:"total"`
	HasMore  bool             `json:"hasMore"`
}

type ProjectDetail struct {
	Project         model.Project                 `json:"project"`
	Units           []model.ProjectUnit           `json:"units"`
	Canvases        []model.CanvasProject         `json:"canvases"`
	CanvasUnitLinks []model.CanvasUnitLink        `json:"canvasUnitLinks"`
	Assets          []ProjectAssetSummary         `json:"assets"`
	AssetFolders    []model.ProjectAssetFolder    `json:"assetFolders"`
	Workflows       []ProjectWorkflowDetail       `json:"workflows"`
	Shots           []model.Shot                  `json:"shots"`
	ShotRevisions   []model.ShotRevision          `json:"shotRevisions"`
	ShotArtifacts   []model.ShotArtifact          `json:"shotArtifacts"`
	ShotReferences  []model.ShotAssetReference    `json:"shotReferences"`
	AssetCandidates []model.ProjectAssetCandidate `json:"assetCandidates"`
	Tasks           []TaskSummary                 `json:"tasks"`
}

func (s *Service) ListProjects(userID string) ([]ProjectSummary, error) {
	projects, err := s.repo.Projects(userID)
	if err != nil {
		return nil, err
	}
	return s.summarizeProjects(userID, projects)
}

func (s *Service) ListProjectsPage(userID string, page int, pageSize int) (ProjectListPage, error) {
	projects, total, err := s.repo.ProjectsPage(userID, page, pageSize)
	if err != nil {
		return ProjectListPage{}, err
	}
	result, err := s.summarizeProjects(userID, projects)
	if err != nil {
		return ProjectListPage{}, err
	}
	return ProjectListPage{Projects: result, Page: page, PageSize: pageSize, Total: total, HasMore: int64(page*pageSize) < total}, nil
}

func (s *Service) summarizeProjects(userID string, projects []model.Project) ([]ProjectSummary, error) {
	result := make([]ProjectSummary, 0, len(projects))
	for _, project := range projects {
		units, unitsErr := s.repo.ProjectUnitSummaries(project.ID)
		if unitsErr != nil {
			return nil, unitsErr
		}
		canvases, canvasesErr := s.repo.ProjectCanvasSummaries(userID, project.ID)
		if canvasesErr != nil {
			return nil, canvasesErr
		}
		assetCount, assetCountErr := s.repo.ProjectAssetCount(project.ID)
		if assetCountErr != nil {
			return nil, assetCountErr
		}
		completed := 0
		for _, unit := range units {
			if unit.Status == model.ProjectUnitStatusCompleted {
				completed++
			}
		}
		result = append(result, ProjectSummary{Project: project, CanvasCount: len(canvases), AssetCount: assetCount, UnitCount: len(units), CompletedUnitCount: completed})
	}
	return result, nil
}

func (s *Service) ProjectDetail(userID string, id string) (ProjectDetail, error) {
	project, err := s.repo.ProjectForUser(userID, id)
	if err != nil {
		return ProjectDetail{}, err
	}
	// 项目读取允许降级修复：旧任务可能已成功持久化图片，但浏览器刷新中断了角色版本绑定。
	if s.reconcileCharacterTurnaroundTasks(userID, project.ID) {
		project, err = s.repo.ProjectForUser(userID, id)
		if err != nil {
			return ProjectDetail{}, err
		}
	}
	if tasks, tasksErr := s.repo.SuccessfulWorkflowTasksForProject(userID, project.ID); tasksErr == nil {
		for _, task := range tasks {
			if err := s.RegisterTaskOutputFromTask(task); err != nil {
				_ = s.log(userID, task.ID, "error", "项目读取时工作流产物补偿失败", err.Error())
			}
		}
	}
	// 项目工作台只返回章节摘要，长篇小说正文由单章接口按需读取。
	units, err := s.repo.ProjectUnitSummaries(project.ID)
	if err != nil {
		return ProjectDetail{}, err
	}
	canvases, err := s.repo.ProjectCanvasSummaries(userID, project.ID)
	if err != nil {
		return ProjectDetail{}, err
	}
	canvasUnitLinks, err := s.repo.ProjectCanvasUnitLinks(project.ID)
	if err != nil {
		return ProjectDetail{}, err
	}
	assets, err := s.ProjectAssets(userID, project.ID)
	if err != nil {
		return ProjectDetail{}, err
	}
	assetFolders, err := s.ProjectAssetFolders(userID, project.ID)
	if err != nil {
		return ProjectDetail{}, err
	}
	workflows, err := s.ProjectWorkflows(project.ID)
	if err != nil {
		return ProjectDetail{}, err
	}
	shots, err := s.repo.ProjectShots(project.ID)
	if err != nil {
		return ProjectDetail{}, err
	}
	shotRevisions, err := s.repo.ProjectShotRevisions(project.ID)
	if err != nil {
		return ProjectDetail{}, err
	}
	shotArtifacts, err := s.repo.ProjectShotArtifacts(project.ID)
	if err != nil {
		return ProjectDetail{}, err
	}
	shotReferences, err := s.repo.ProjectShotAssetReferences(project.ID)
	if err != nil {
		return ProjectDetail{}, err
	}
	candidates, err := s.repo.ProjectAssetCandidates(project.ID)
	if err != nil {
		return ProjectDetail{}, err
	}
	tasks, err := s.TasksWithOptions(userID, TaskListOptions{Limit: 100, ProjectID: project.ID})
	if err != nil {
		return ProjectDetail{}, err
	}
	return ProjectDetail{Project: *project, Units: units, Canvases: canvases, CanvasUnitLinks: canvasUnitLinks, Assets: assets, AssetFolders: assetFolders, Workflows: workflows, Shots: shots, ShotRevisions: shotRevisions, ShotArtifacts: shotArtifacts, ShotReferences: shotReferences, AssetCandidates: candidates, Tasks: tasks}, nil
}

func (s *Service) CreateProject(userID string, req CreateProjectRequest) (model.Project, error) {
	if err := s.EnsureBuiltinProjectWorkflowTemplate(); err != nil {
		return model.Project{}, err
	}
	name := strings.TrimSpace(req.Name)
	if name == "" {
		return model.Project{}, BadAuthRequest("项目名称不能为空")
	}
	projectType := strings.TrimSpace(req.Type)
	if projectType == "" {
		projectType = "short-drama"
	}
	aspectRatio := strings.TrimSpace(req.AspectRatio)
	if aspectRatio == "" {
		aspectRatio = "9:16"
	}
	sourceType := strings.TrimSpace(req.SourceType)
	if sourceType == "" {
		sourceType = "blank"
	}
	styleProfileJSON, err := validateStyleProfileJSON(req.StyleProfileJSON)
	if err != nil {
		return model.Project{}, BadAuthRequest(err.Error())
	}
	stylePresetID := strings.TrimSpace(req.StylePresetID)
	if err := validateStyleProfilePreset(stylePresetID, styleProfileJSON); err != nil {
		return model.Project{}, BadAuthRequest(err.Error())
	}
	now := time.Now()
	defaultImageModel, err := normalizeProjectDefaultModel(req.DefaultImageModel)
	if err != nil {
		return model.Project{}, err
	}
	defaultVideoModel, err := normalizeProjectDefaultModel(req.DefaultVideoModel)
	if err != nil {
		return model.Project{}, err
	}
	project := model.Project{ID: newID(), UserID: userID, Name: name, Type: projectType, AspectRatio: aspectRatio, SourceType: sourceType, Description: strings.TrimSpace(req.Description), StylePresetID: stylePresetID, StyleProfileJSON: styleProfileJSON, DefaultImageModel: defaultImageModel, DefaultVideoModel: defaultVideoModel, Status: model.ProjectStatusActive, Revision: 1, CreatedAt: now, UpdatedAt: now}
	if err := s.repo.CreateProject(&project); err != nil {
		if errors.Is(err, repository.ErrProjectNameConflict) {
			// 项目名称冲突需要明确返回 409，页面才能按已有逻辑换一个名称重试。
			conflict := NewAppError(http.StatusConflict, "项目名称已存在")
			conflict.Reason = ReasonProjectNameConflict
			return model.Project{}, conflict
		}
		return model.Project{}, err
	}
	if _, err := s.createProjectWorkflow(project.ID, "", "project"); err != nil {
		if deleteErr := s.repo.DeleteProject(userID, project.ID, nil); deleteErr != nil {
			return model.Project{}, errors.Join(err, fmt.Errorf("项目初始化失败，回滚项目记录失败：%w", deleteErr))
		}
		return model.Project{}, err
	}
	project.Revision++
	project.UpdatedAt = time.Now()
	return project, nil
}

func (s *Service) UpdateProject(userID string, id string, req UpdateProjectRequest) (model.Project, error) {
	project, err := s.repo.ProjectForUser(userID, id)
	if err != nil {
		return model.Project{}, err
	}
	if name := strings.TrimSpace(req.Name); name != "" {
		project.Name = name
	}
	if value := strings.TrimSpace(req.Type); value != "" {
		project.Type = value
	}
	if value := strings.TrimSpace(req.AspectRatio); value != "" {
		project.AspectRatio = value
	}
	if value := strings.TrimSpace(req.SourceType); value != "" {
		project.SourceType = value
	}
	if req.Description != nil {
		project.Description = strings.TrimSpace(*req.Description)
	}
	if req.CoverResourceID != nil {
		coverResourceID := strings.TrimSpace(*req.CoverResourceID)
		if coverResourceID != "" {
			resource, resourceErr := s.repo.ResourceForUser(userID, coverResourceID)
			if resourceErr != nil {
				if errors.Is(resourceErr, gorm.ErrRecordNotFound) {
					return model.Project{}, BadAuthRequest("项目主图不存在或不属于当前用户")
				}
				return model.Project{}, resourceErr
			}
			if resource.Status != model.ResourceStatusReady || resource.Kind != "image" {
				return model.Project{}, BadAuthRequest("项目主图必须是已就绪的图片资源")
			}
		}
		project.CoverResourceID = coverResourceID
	}
	if req.StylePresetID != nil {
		project.StylePresetID = strings.TrimSpace(*req.StylePresetID)
	}
	if req.StyleProfileJSON != nil {
		styleProfileJSON, profileErr := validateStyleProfileJSON(*req.StyleProfileJSON)
		if profileErr != nil {
			return model.Project{}, BadAuthRequest(profileErr.Error())
		}
		project.StyleProfileJSON = styleProfileJSON
	}
	if req.DefaultImageModel != nil {
		defaultImageModel, modelErr := normalizeProjectDefaultModel(*req.DefaultImageModel)
		if modelErr != nil {
			return model.Project{}, modelErr
		}
		project.DefaultImageModel = defaultImageModel
	}
	if req.DefaultVideoModel != nil {
		defaultVideoModel, modelErr := normalizeProjectDefaultModel(*req.DefaultVideoModel)
		if modelErr != nil {
			return model.Project{}, modelErr
		}
		project.DefaultVideoModel = defaultVideoModel
	}
	if err := validateStyleProfilePreset(project.StylePresetID, project.StyleProfileJSON); err != nil {
		return model.Project{}, BadAuthRequest(err.Error())
	}
	if status := model.ProjectStatus(strings.TrimSpace(req.Status)); status != "" {
		if status != model.ProjectStatusActive && status != model.ProjectStatusArchived {
			return model.Project{}, BadAuthRequest("不支持的项目状态")
		}
		project.Status = status
	}
	project.Revision++
	project.UpdatedAt = time.Now()
	if err := s.repo.UpdateProject(project); err != nil {
		return model.Project{}, err
	}
	return *project, nil
}

func normalizeProjectDefaultModel(value string) (string, error) {
	modelRef := strings.TrimSpace(value)
	if len(modelRef) > 500 {
		return "", BadAuthRequest("项目默认模型标识过长")
	}
	return modelRef, nil
}

func (s *Service) DeleteProject(userID string, id string) error {
	if _, err := s.repo.ProjectForUser(userID, id); err != nil {
		return err
	}
	canvases, err := s.repo.ProjectCanvasDocuments(userID, id)
	if err != nil {
		return err
	}
	projectScopeIDs := make([]string, 0, len(canvases)+1)
	projectScopeIDs = append(projectScopeIDs, id)
	canvasUpdates := make([]model.CanvasProject, 0, len(canvases))
	deleteTime := time.Now()
	for _, canvas := range canvases {
		payloadJSON, payloadErr := canvasPayloadWithoutProject(canvas.PayloadJSON, deleteTime)
		if payloadErr != nil {
			return payloadErr
		}
		canvas.PayloadJSON = payloadJSON
		canvas.UpdatedAt = deleteTime
		canvasUpdates = append(canvasUpdates, canvas)
		projectScopeIDs = append(projectScopeIDs, canvas.ID)
	}
	activeTaskCount, err := s.repo.ActiveTaskCountForProjectIDs(userID, projectScopeIDs)
	if err != nil {
		return err
	}
	if activeTaskCount > 0 {
		return BadAuthRequest("项目仍有进行中的生成任务，请等待任务完成或取消后再删除")
	}
	if err := s.repo.DeleteProject(userID, id, canvasUpdates); err != nil {
		if errors.Is(err, repository.ErrProjectHasActiveTasks) {
			return BadAuthRequest("项目仍有进行中的生成任务，请等待任务完成或取消后再删除")
		}
		return err
	}
	return nil
}

func (s *Service) activeProjectForUser(userID string, projectID string) (*model.Project, error) {
	project, err := s.repo.ProjectForUser(userID, projectID)
	if err != nil {
		return nil, err
	}
	if project.Status == model.ProjectStatusArchived {
		return nil, BadAuthRequest("项目已归档，不能修改短剧生产数据")
	}
	return project, nil
}

func (s *Service) CreateProjectUnit(userID string, projectID string, req CreateProjectUnitRequest) (model.ProjectUnit, error) {
	if _, err := s.repo.ProjectForUser(userID, projectID); err != nil {
		return model.ProjectUnit{}, err
	}
	unit, err := newProjectUnit(projectID, req, req.Position)
	if err != nil {
		return model.ProjectUnit{}, err
	}
	if err := s.repo.CreateProjectUnit(&unit); err != nil {
		return model.ProjectUnit{}, err
	}
	if err := s.repo.BumpProjectRevision(projectID); err != nil {
		return model.ProjectUnit{}, err
	}
	return unit, nil
}

func (s *Service) GetProjectUnit(userID string, projectID string, unitID string) (model.ProjectUnit, error) {
	if _, err := s.repo.ProjectForUser(userID, projectID); err != nil {
		return model.ProjectUnit{}, err
	}
	unit, err := s.repo.ProjectUnit(projectID, strings.TrimSpace(unitID))
	if err != nil {
		return model.ProjectUnit{}, err
	}
	return *unit, nil
}

func (s *Service) ImportProjectUnits(userID string, projectID string, req ImportProjectUnitsRequest) ([]model.ProjectUnit, error) {
	if _, err := s.repo.ProjectForUser(userID, projectID); err != nil {
		return nil, err
	}
	if len(req.Units) == 0 || len(req.Units) > 2500 {
		return nil, BadAuthRequest("一次导入的章节数量必须在 1 到 2500 之间")
	}
	existing, err := s.repo.ProjectUnits(projectID)
	if err != nil {
		return nil, err
	}
	units := make([]model.ProjectUnit, 0, len(req.Units))
	for index, input := range req.Units {
		unit, unitErr := newProjectUnit(projectID, input, len(existing)+index)
		if unitErr != nil {
			return nil, unitErr
		}
		units = append(units, unit)
	}
	if err := s.repo.ImportProjectUnits(projectID, units); err != nil {
		return nil, err
	}
	return units, nil
}

func (s *Service) ReorderProjectUnits(userID string, projectID string, req ReorderProjectUnitsRequest) error {
	if _, err := s.repo.ProjectForUser(userID, projectID); err != nil {
		return err
	}
	units, err := s.repo.ProjectUnits(projectID)
	if err != nil {
		return err
	}
	if len(req.UnitIDs) != len(units) {
		return BadAuthRequest("章节排序列表不完整")
	}
	existing := make(map[string]struct{}, len(units))
	for _, unit := range units {
		existing[unit.ID] = struct{}{}
	}
	seen := make(map[string]struct{}, len(req.UnitIDs))
	normalizedIDs := make([]string, 0, len(req.UnitIDs))
	for _, rawID := range req.UnitIDs {
		id := strings.TrimSpace(rawID)
		if _, ok := existing[id]; !ok {
			return BadAuthRequest("章节排序包含无效章节")
		}
		if _, duplicate := seen[id]; duplicate {
			return BadAuthRequest("章节排序包含重复章节")
		}
		seen[id] = struct{}{}
		normalizedIDs = append(normalizedIDs, id)
	}
	return s.repo.ReorderProjectUnits(projectID, normalizedIDs)
}

func (s *Service) DeleteProjectUnit(userID string, projectID string, unitID string) error {
	if _, err := s.repo.ProjectForUser(userID, projectID); err != nil {
		return err
	}
	if _, err := s.repo.ProjectUnit(projectID, unitID); err != nil {
		return err
	}
	return s.repo.DeleteProjectUnit(projectID, unitID)
}

func newProjectUnit(projectID string, req CreateProjectUnitRequest, position int) (model.ProjectUnit, error) {
	kind := model.ProjectUnitKind(strings.TrimSpace(req.Kind))
	if kind == "" {
		kind = model.ProjectUnitKindChapter
	}
	if kind != model.ProjectUnitKindChapter && kind != model.ProjectUnitKindEpisode {
		return model.ProjectUnit{}, BadAuthRequest("不支持的项目单元类型")
	}
	title := model.NormalizeProjectUnitTitle(req.Title)
	if title == "" {
		return model.ProjectUnit{}, BadAuthRequest("章节标题不能为空")
	}
	if !model.ValidProjectUnitTitle(title) {
		return model.ProjectUnit{}, BadAuthRequest("章节标题不能超过 240 个字符")
	}
	if position < 0 {
		position = 0
	}
	now := time.Now()
	unit := model.ProjectUnit{ID: newID(), ProjectID: projectID, Kind: kind, Title: title, SourceText: req.SourceText, WordCount: model.ProjectUnitWordCount(req.SourceText), Status: model.ProjectUnitStatusDraft, Position: position, CreatedAt: now, UpdatedAt: now}
	return unit, nil
}

func (s *Service) UpdateProjectUnit(userID string, projectID string, unitID string, req UpdateProjectUnitRequest) (model.ProjectUnit, error) {
	if _, err := s.repo.ProjectForUser(userID, projectID); err != nil {
		return model.ProjectUnit{}, err
	}
	unit, err := s.repo.ProjectUnit(projectID, unitID)
	if err != nil {
		return model.ProjectUnit{}, err
	}
	sourceChanged := unit.SourceText != req.SourceText
	if title := model.NormalizeProjectUnitTitle(req.Title); title != "" {
		if !model.ValidProjectUnitTitle(title) {
			return model.ProjectUnit{}, BadAuthRequest("章节标题不能超过 240 个字符")
		}
		unit.Title = title
	}
	unit.SourceText = req.SourceText
	unit.WordCount = model.ProjectUnitWordCount(req.SourceText)
	if status := model.ProjectUnitStatus(strings.TrimSpace(req.Status)); status != "" {
		if status != model.ProjectUnitStatusDraft && status != model.ProjectUnitStatusReady && status != model.ProjectUnitStatusCompleted {
			return model.ProjectUnit{}, BadAuthRequest("不支持的章节状态")
		}
		unit.Status = status
	}
	unit.UpdatedAt = time.Now()
	if err := s.repo.UpdateProjectUnit(unit, sourceChanged); err != nil {
		return model.ProjectUnit{}, err
	}
	return *unit, nil
}

func (s *Service) LinkCanvasUnit(userID string, projectID string, req LinkCanvasUnitRequest) (model.CanvasUnitLink, error) {
	if _, err := s.repo.ProjectForUser(userID, projectID); err != nil {
		return model.CanvasUnitLink{}, err
	}
	canvasID := strings.TrimSpace(req.CanvasID)
	unitID := strings.TrimSpace(req.UnitID)
	if canvasID == "" || unitID == "" {
		return model.CanvasUnitLink{}, BadAuthRequest("画布和章节不能为空")
	}
	if _, err := s.repo.CanvasProjectForUser(userID, canvasID); err != nil {
		return model.CanvasUnitLink{}, err
	}
	if _, err := s.repo.ProjectUnit(projectID, unitID); err != nil {
		return model.CanvasUnitLink{}, err
	}
	if err := s.repo.AssignCanvasToProject(userID, canvasID, projectID); err != nil {
		return model.CanvasUnitLink{}, err
	}
	role := strings.TrimSpace(req.Role)
	if role == "" {
		role = "storyboard"
	}
	now := time.Now()
	link := model.CanvasUnitLink{ID: newID(), ProjectID: projectID, CanvasID: canvasID, UnitID: unitID, Role: role, CreatedAt: now}
	if err := s.repo.UpsertCanvasUnitLink(&link); err != nil {
		return model.CanvasUnitLink{}, err
	}
	if err := s.repo.BumpProjectRevision(projectID); err != nil {
		return model.CanvasUnitLink{}, err
	}
	return link, nil
}

func (s *Service) UnlinkCanvasUnit(userID string, projectID string, canvasID string, unitID string) error {
	if _, err := s.repo.ProjectForUser(userID, projectID); err != nil {
		return err
	}
	canvas, err := s.repo.CanvasProjectForUser(userID, strings.TrimSpace(canvasID))
	if err != nil {
		return err
	}
	if canvas.ProjectID != projectID {
		return BadAuthRequest("画布不属于当前项目")
	}
	if _, err := s.repo.CanvasUnitLink(projectID, canvas.ID, strings.TrimSpace(unitID)); err != nil {
		return err
	}
	return s.repo.DeleteCanvasUnitLink(projectID, canvas.ID, strings.TrimSpace(unitID))
}

func (s *Service) UnlinkCanvasProject(userID string, projectID string, canvasID string) error {
	if _, err := s.repo.ProjectForUser(userID, projectID); err != nil {
		return err
	}
	canvas, err := s.repo.CanvasProjectForUser(userID, strings.TrimSpace(canvasID))
	if err != nil {
		return err
	}
	if canvas.ProjectID != projectID {
		return BadAuthRequest("画布不属于当前项目")
	}
	now := time.Now()
	payloadJSON, err := canvasPayloadWithoutProject(canvas.PayloadJSON, now)
	if err != nil {
		return err
	}
	// 关系列、同步快照和更新时间必须原子更新，否则浏览器会用旧 projectId 把关系重新写回。
	return s.repo.UnassignCanvasFromProject(userID, projectID, canvas.ID, payloadJSON, now, canvas.Revision)
}

func canvasPayloadWithoutProject(payloadJSON string, updatedAt time.Time) (string, error) {
	var payload map[string]any
	if err := json.Unmarshal([]byte(payloadJSON), &payload); err != nil {
		return "", BadAuthRequest("画布数据格式错误，无法解除项目关系")
	}
	delete(payload, "projectId")
	payload["updatedAt"] = updatedAt.Format(time.RFC3339Nano)
	next, err := json.Marshal(payload)
	if err != nil {
		return "", err
	}
	return string(next), nil
}

func IsProjectNotFound(err error) bool {
	return errors.Is(err, gorm.ErrRecordNotFound)
}

// 任务仍以画布 ID 作为 projectId；写入前必须解析到业务项目并阻止归档项目继续生成。
func (s *Service) ensureTaskProjectActive(userID string, canvasOrProjectID string) error {
	id := strings.TrimSpace(canvasOrProjectID)
	if id == "" {
		return nil
	}
	if canvas, err := s.repo.CanvasProjectForUser(userID, id); err == nil {
		if canvas.ProjectID == "" {
			return nil
		}
		project, projectErr := s.repo.ProjectForUser(userID, canvas.ProjectID)
		if projectErr != nil {
			return projectErr
		}
		if project.Status == model.ProjectStatusArchived {
			return BadAuthRequest("项目已归档，无法创建生成任务")
		}
		return nil
	} else if !errors.Is(err, gorm.ErrRecordNotFound) {
		return err
	}
	project, err := s.repo.ProjectForUser(userID, id)
	if err != nil {
		if errors.Is(err, gorm.ErrRecordNotFound) {
			return nil
		}
		return err
	}
	if project.Status == model.ProjectStatusArchived {
		return BadAuthRequest("项目已归档，无法创建生成任务")
	}
	return nil
}