feat: add backend logic for determining tasks tab visibility (#18401)

This PR implements the backend logic for determining if the Tasks tab
should be visible in the web UI as described in [the
RFC](https://www.notion.so/coderhq/Coder-Tasks-207d579be5928053ab68c8d9a4b59eaa?source=copy_link#210d579be5928013ab5acbe69a2f548b).

The frontend component will be added in a follow-up PR once the entire
Tasks backend is implemented so as not to break the dogfood environment
until then.

coderd/database/dbauthz/dbauthz.go

@@ -3451,6 +3451,11 @@ func (q *querier) GetWorkspacesEligibleForTransition(ctx context.Context, now ti
 	return q.db.GetWorkspacesEligibleForTransition(ctx, now)
 }
 
+func (q *querier) HasTemplateVersionsWithAITask(ctx context.Context) (bool, error) {
+	// Anyone can call HasTemplateVersionsWithAITask.
+	return q.db.HasTemplateVersionsWithAITask(ctx)
+}
+
 func (q *querier) InsertAPIKey(ctx context.Context, arg database.InsertAPIKeyParams) (database.APIKey, error) {
 	return insert(q.log, q.auth,
 		rbac.ResourceApiKey.WithOwner(arg.UserID.String()),

coderd/database/dbauthz/dbauthz_test.go

@@ -4566,6 +4566,9 @@ func (s *MethodTestSuite) TestSystemFunctions() {
 	s.Run("GetProvisionerJobByIDForUpdate", s.Subtest(func(db database.Store, check *expects) {
 		check.Args(uuid.New()).Asserts(rbac.ResourceProvisionerJobs, policy.ActionRead).Errors(sql.ErrNoRows)
 	}))
+	s.Run("HasTemplateVersionsWithAITask", s.Subtest(func(db database.Store, check *expects) {
+		check.Args().Asserts()
+	}))
 }
 
 func (s *MethodTestSuite) TestNotifications() {

coderd/database/dbmem/dbmem.go

@@ -8495,6 +8495,19 @@ func (q *FakeQuerier) GetWorkspacesEligibleForTransition(ctx context.Context, no
 	return workspaces, nil
 }
 
+func (q *FakeQuerier) HasTemplateVersionsWithAITask(_ context.Context) (bool, error) {
+	q.mutex.RLock()
+	defer q.mutex.RUnlock()
+
+	for _, templateVersion := range q.templateVersions {
+		if templateVersion.HasAITask {
+			return true, nil
+		}
+	}
+
+	return false, nil
+}
+
 func (q *FakeQuerier) InsertAPIKey(_ context.Context, arg database.InsertAPIKeyParams) (database.APIKey, error) {
 	if err := validateDatabaseType(arg); err != nil {
 		return database.APIKey{}, err

coderd/database/dbmetrics/querymetrics.go

@@ -2041,6 +2041,13 @@ func (m queryMetricsStore) GetWorkspacesEligibleForTransition(ctx context.Contex
 	return workspaces, err
 }
 
+func (m queryMetricsStore) HasTemplateVersionsWithAITask(ctx context.Context) (bool, error) {
+	start := time.Now()
+	r0, r1 := m.s.HasTemplateVersionsWithAITask(ctx)
+	m.queryLatencies.WithLabelValues("HasTemplateVersionsWithAITask").Observe(time.Since(start).Seconds())
+	return r0, r1
+}
+
 func (m queryMetricsStore) InsertAPIKey(ctx context.Context, arg database.InsertAPIKeyParams) (database.APIKey, error) {
 	start := time.Now()
 	key, err := m.s.InsertAPIKey(ctx, arg)

coderd/database/dbmock/dbmock.go

@@ -4292,6 +4292,21 @@ func (mr *MockStoreMockRecorder) GetWorkspacesEligibleForTransition(ctx, now any
 	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "GetWorkspacesEligibleForTransition", reflect.TypeOf((*MockStore)(nil).GetWorkspacesEligibleForTransition), ctx, now)
 }
 
+// HasTemplateVersionsWithAITask mocks base method.
+func (m *MockStore) HasTemplateVersionsWithAITask(ctx context.Context) (bool, error) {
+	m.ctrl.T.Helper()
+	ret := m.ctrl.Call(m, "HasTemplateVersionsWithAITask", ctx)
+	ret0, _ := ret[0].(bool)
+	ret1, _ := ret[1].(error)
+	return ret0, ret1
+}
+
+// HasTemplateVersionsWithAITask indicates an expected call of HasTemplateVersionsWithAITask.
+func (mr *MockStoreMockRecorder) HasTemplateVersionsWithAITask(ctx any) *gomock.Call {
+	mr.mock.ctrl.T.Helper()
+	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "HasTemplateVersionsWithAITask", reflect.TypeOf((*MockStore)(nil).HasTemplateVersionsWithAITask), ctx)
+}
+
 // InTx mocks base method.
 func (m *MockStore) InTx(arg0 func(database.Store) error, arg1 *database.TxOptions) error {
 	m.ctrl.T.Helper()

coderd/database/querier.go

@@ -462,6 +462,8 @@ type sqlcQuerier interface {
 	GetWorkspacesAndAgentsByOwnerID(ctx context.Context, ownerID uuid.UUID) ([]GetWorkspacesAndAgentsByOwnerIDRow, error)
 	GetWorkspacesByTemplateID(ctx context.Context, templateID uuid.UUID) ([]WorkspaceTable, error)
 	GetWorkspacesEligibleForTransition(ctx context.Context, now time.Time) ([]GetWorkspacesEligibleForTransitionRow, error)
+	// Determines if the template versions table has any rows with has_ai_task = TRUE.
+	HasTemplateVersionsWithAITask(ctx context.Context) (bool, error)
 	InsertAPIKey(ctx context.Context, arg InsertAPIKeyParams) (APIKey, error)
 	// We use the organization_id as the id
 	// for simplicity since all users is

coderd/database/queries.sql.go

@@ -11806,6 +11806,18 @@ func (q *sqlQuerier) GetTemplateVersionsCreatedAfter(ctx context.Context, create
 	return items, nil
 }
 
+const hasTemplateVersionsWithAITask = `-- name: HasTemplateVersionsWithAITask :one
+SELECT EXISTS (SELECT 1 FROM template_versions WHERE has_ai_task = TRUE)
+`
+
+// Determines if the template versions table has any rows with has_ai_task = TRUE.
+func (q *sqlQuerier) HasTemplateVersionsWithAITask(ctx context.Context) (bool, error) {
+	row := q.db.QueryRowContext(ctx, hasTemplateVersionsWithAITask)
+	var exists bool
+	err := row.Scan(&exists)
+	return exists, err
+}
+
 const insertTemplateVersion = `-- name: InsertTemplateVersion :exec
 INSERT INTO
 	template_versions (

coderd/database/queries/templateversions.sql

@@ -226,3 +226,7 @@ FROM
 WHERE
 	template_versions.id IN (archived_versions.id)
 RETURNING template_versions.id;
+
+-- name: HasTemplateVersionsWithAITask :one
+-- Determines if the template versions table has any rows with has_ai_task = TRUE.
+SELECT EXISTS (SELECT 1 FROM template_versions WHERE has_ai_task = TRUE);