From 530fc43cca3c2198997c908010ac4e991ec0c35a Mon Sep 17 00:00:00 2001
From: yanweidong <david.yan@qq.com>
Date: Sat, 18 Jul 2026 16:01:25 +0800
Subject: [PATCH] feat: add task assignment sharing

---
 backend/internal/tasks/service.go      | 84 ++++++++++++++++++++++++++
 backend/internal/tasks/service_test.go | 62 +++++++++++++++++++
 2 files changed, 146 insertions(+)
 create mode 100644 backend/internal/tasks/service.go
 create mode 100644 backend/internal/tasks/service_test.go

diff --git a/backend/internal/tasks/service.go b/backend/internal/tasks/service.go
new file mode 100644
index 0000000..8bc65b4
--- /dev/null
+++ b/backend/internal/tasks/service.go
@@ -0,0 +1,84 @@
+package tasks
+
+import (
+	"errors"
+	"fmt"
+
+	"gorm.io/gorm"
+	"senlinai-agent/backend/internal/domain"
+)
+
+type Service struct {
+	db *gorm.DB
+}
+
+type LinkedObject struct {
+	ObjectType string `json:"object_type"`
+	ObjectID   uint   `json:"object_id"`
+}
+
+func NewService(database *gorm.DB) *Service {
+	return &Service{db: database}
+}
+
+func (s *Service) Assign(taskID uint, assigneeID uint) error {
+	return s.db.Transaction(func(tx *gorm.DB) error {
+		var task domain.Task
+		if err := tx.First(&task, taskID).Error; err != nil {
+			return err
+		}
+		if err := tx.Model(&task).Update("assignee_id", assigneeID).Error; err != nil {
+			return err
+		}
+		return tx.Create(&domain.ProjectEvent{
+			ProjectID:  task.ProjectID,
+			ActorID:    task.CreatedBy,
+			EventType:  "task_assigned",
+			EntityType: "task",
+			EntityID:   task.ID,
+			Summary:    fmt.Sprintf("Task assigned to user %d", assigneeID),
+		}).Error
+	})
+}
+
+func (s *Service) ShareObject(taskID uint, objectType string, objectID uint) error {
+	if objectType != "note" && objectType != "source" {
+		return errors.New("unsupported shared object type")
+	}
+	return s.db.Transaction(func(tx *gorm.DB) error {
+		var task domain.Task
+		if err := tx.First(&task, taskID).Error; err != nil {
+			return err
+		}
+		if err := tx.Create(&domain.TaskShare{TaskID: taskID, ObjectType: objectType, ObjectID: objectID}).Error; err != nil {
+			return err
+		}
+		return tx.Create(&domain.ProjectEvent{
+			ProjectID:  task.ProjectID,
+			ActorID:    task.CreatedBy,
+			EventType:  "task_object_shared",
+			EntityType: "task",
+			EntityID:   task.ID,
+			Summary:    fmt.Sprintf("Shared %s %d with task", objectType, objectID),
+		}).Error
+	})
+}
+
+func (s *Service) VisibleLinkedObjects(taskID uint, viewerID uint) ([]LinkedObject, error) {
+	var task domain.Task
+	if err := s.db.First(&task, taskID).Error; err != nil {
+		return nil, err
+	}
+	if task.AssigneeID == nil || *task.AssigneeID != viewerID {
+		return []LinkedObject{}, nil
+	}
+	var shares []domain.TaskShare
+	if err := s.db.Where("task_id = ?", taskID).Find(&shares).Error; err != nil {
+		return nil, err
+	}
+	objects := make([]LinkedObject, 0, len(shares))
+	for _, share := range shares {
+		objects = append(objects, LinkedObject{ObjectType: share.ObjectType, ObjectID: share.ObjectID})
+	}
+	return objects, nil
+}
diff --git a/backend/internal/tasks/service_test.go b/backend/internal/tasks/service_test.go
new file mode 100644
index 0000000..3a2eaf4
--- /dev/null
+++ b/backend/internal/tasks/service_test.go
@@ -0,0 +1,62 @@
+package tasks
+
+import (
+	"fmt"
+	"testing"
+
+	"github.com/glebarez/sqlite"
+	"github.com/stretchr/testify/require"
+	"gorm.io/gorm"
+	"senlinai-agent/backend/internal/domain"
+)
+
+func TestAssigneeOnlySeesExplicitlySharedObjects(t *testing.T) {
+	database := newTestDB(t)
+	assigneeID := uint(2)
+	task := domain.Task{ProjectID: 1, CreatedBy: 1, AssigneeID: &assigneeID, Title: "处理合同"}
+	note := domain.Note{ProjectID: 1, CreatedBy: 1, Title: "合同背景", Markdown: "只在共享后可见"}
+	require.NoError(t, database.Create(&task).Error)
+	require.NoError(t, database.Create(&note).Error)
+	service := NewService(database)
+
+	before, err := service.VisibleLinkedObjects(task.ID, assigneeID)
+	require.NoError(t, err)
+	require.Empty(t, before)
+
+	require.NoError(t, service.ShareObject(task.ID, "note", note.ID))
+	after, err := service.VisibleLinkedObjects(task.ID, assigneeID)
+	require.NoError(t, err)
+	require.Len(t, after, 1)
+	require.Equal(t, "note", after[0].ObjectType)
+	require.Equal(t, note.ID, after[0].ObjectID)
+}
+
+func TestShareObjectRejectsUnsupportedType(t *testing.T) {
+	database := newTestDB(t)
+	service := NewService(database)
+
+	err := service.ShareObject(1, "ai_session", 9)
+
+	require.ErrorContains(t, err, "unsupported shared object type")
+}
+
+func TestAssignRecordsProjectEvent(t *testing.T) {
+	database := newTestDB(t)
+	task := domain.Task{ProjectID: 7, CreatedBy: 1, Title: "安排评审"}
+	require.NoError(t, database.Create(&task).Error)
+	service := NewService(database)
+
+	require.NoError(t, service.Assign(task.ID, 2))
+
+	var event domain.ProjectEvent
+	require.NoError(t, database.Where("project_id = ? AND entity_type = ? AND entity_id = ?", 7, "task", task.ID).First(&event).Error)
+	require.Equal(t, "task_assigned", event.EventType)
+}
+
+func newTestDB(t *testing.T) *gorm.DB {
+	t.Helper()
+	database, err := gorm.Open(sqlite.Open(fmt.Sprintf("file:%s?mode=memory&cache=shared", t.Name())), &gorm.Config{})
+	require.NoError(t, err)
+	require.NoError(t, domain.AutoMigrate(database))
+	return database
+}