Fix various problems around projects board view (#30696)

# The problem
The previous implementation will start multiple POST requests from the
frontend when moving a column and another bug is moving the default
column will never be remembered in fact.

# What's changed

- [x] This PR will allow the default column to move to a non-first
position
- [x] And it also uses one request instead of multiple requests when
moving the columns
- [x] Use a star instead of a pin as the icon for setting the default
column action
- [x] Inserted new column will be append to the end
- [x] Fix #30701 the newly added issue will be append to the end of the
default column
- [x] Fix when deleting a column, all issues in it will be displayed
from UI but database records exist.
- [x] Add a limitation for columns in a project to 20. So the sorting
will not be overflow because it's int8.

---------

Co-authored-by: silverwind <me@silverwind.io>
Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>

2 files changed, 67 insertions, 3 deletions

diff --git a/tests/integration/org_project_test.go b/tests/integration/org_project_test.go
index a14004f6b0..ca39cf5130 100644
--- a/tests/integration/org_project_test.go
+++ b/tests/integration/org_project_test.go
@@ -5,17 +5,17 @@ package integration
 
 import (
 	"net/http"
+	"slices"
 	"testing"
 
 	unit_model "code.gitea.io/gitea/models/unit"
+	"code.gitea.io/gitea/modules/test"
 	"code.gitea.io/gitea/tests"
 )
 
 func TestOrgProjectAccess(t *testing.T) {
 	defer tests.PrepareTestEnv(t)()
-
-	// disable repo project unit
-	unit_model.DisabledRepoUnits = []unit_model.Type{unit_model.TypeProjects}
+	defer test.MockVariableValue(&unit_model.DisabledRepoUnits, append(slices.Clone(unit_model.DisabledRepoUnits), unit_model.TypeProjects))()
 
 	// repo project, 404
 	req := NewRequest(t, "GET", "/user2/repo1/projects")
diff --git a/tests/integration/project_test.go b/tests/integration/project_test.go
index 45061c5b24..1d9c3aae53 100644
--- a/tests/integration/project_test.go
+++ b/tests/integration/project_test.go
@@ -4,10 +4,18 @@
 package integration
 
 import (
+	"fmt"
 	"net/http"
 	"testing"
 
+	"code.gitea.io/gitea/models/db"
+	project_model "code.gitea.io/gitea/models/project"
+	repo_model "code.gitea.io/gitea/models/repo"
+	"code.gitea.io/gitea/models/unit"
+	"code.gitea.io/gitea/models/unittest"
 	"code.gitea.io/gitea/tests"
+
+	"github.com/stretchr/testify/assert"
 )
 
 func TestPrivateRepoProject(t *testing.T) {
@@ -21,3 +29,59 @@ func TestPrivateRepoProject(t *testing.T) {
 	req = NewRequest(t, "GET", "/user31/-/projects")
 	sess.MakeRequest(t, req, http.StatusOK)
 }
+
+func TestMoveRepoProjectColumns(t *testing.T) {
+	defer tests.PrepareTestEnv(t)()
+
+	repo2 := unittest.AssertExistsAndLoadBean(t, &repo_model.Repository{ID: 2})
+
+	projectsUnit := repo2.MustGetUnit(db.DefaultContext, unit.TypeProjects)
+	assert.True(t, projectsUnit.ProjectsConfig().IsProjectsAllowed(repo_model.ProjectsModeRepo))
+
+	project1 := project_model.Project{
+		Title:     "new created project",
+		RepoID:    repo2.ID,
+		Type:      project_model.TypeRepository,
+		BoardType: project_model.BoardTypeNone,
+	}
+	err := project_model.NewProject(db.DefaultContext, &project1)
+	assert.NoError(t, err)
+
+	for i := 0; i < 3; i++ {
+		err = project_model.NewBoard(db.DefaultContext, &project_model.Board{
+			Title:     fmt.Sprintf("column %d", i+1),
+			ProjectID: project1.ID,
+		})
+		assert.NoError(t, err)
+	}
+
+	columns, err := project1.GetBoards(db.DefaultContext)
+	assert.NoError(t, err)
+	assert.Len(t, columns, 3)
+	assert.EqualValues(t, 0, columns[0].Sorting)
+	assert.EqualValues(t, 1, columns[1].Sorting)
+	assert.EqualValues(t, 2, columns[2].Sorting)
+
+	sess := loginUser(t, "user1")
+	req := NewRequest(t, "GET", fmt.Sprintf("/%s/projects/%d", repo2.FullName(), project1.ID))
+	resp := sess.MakeRequest(t, req, http.StatusOK)
+	htmlDoc := NewHTMLParser(t, resp.Body)
+
+	req = NewRequestWithJSON(t, "POST", fmt.Sprintf("/%s/projects/%d/move?_csrf="+htmlDoc.GetCSRF(), repo2.FullName(), project1.ID), map[string]any{
+		"columns": []map[string]any{
+			{"columnID": columns[1].ID, "sorting": 0},
+			{"columnID": columns[2].ID, "sorting": 1},
+			{"columnID": columns[0].ID, "sorting": 2},
+		},
+	})
+	sess.MakeRequest(t, req, http.StatusOK)
+
+	columnsAfter, err := project1.GetBoards(db.DefaultContext)
+	assert.NoError(t, err)
+	assert.Len(t, columns, 3)
+	assert.EqualValues(t, columns[1].ID, columnsAfter[0].ID)
+	assert.EqualValues(t, columns[2].ID, columnsAfter[1].ID)
+	assert.EqualValues(t, columns[0].ID, columnsAfter[2].ID)
+
+	assert.NoError(t, project_model.DeleteProjectByID(db.DefaultContext, project1.ID))
+}