package cabana

import (
	"context"
	"errors"
	"strings"

	"git.golem15.com/golem15/summercms/modules/backpack"
	"git.golem15.com/golem15/summercms/modules/pact"
	"gorm.io/gorm"
)

// usersAdmin is the Administrators screen (summercms.cabana.users), the
// WinterCMS Backend\Controllers\Users controller over backend_users. Every
// route needs backend.manage_users. screens gives access to the activating
// app and the compiled registry at request time.
type usersAdmin struct {
	screens *backendScreens
}

var (
	_ pact.AdminController   = usersAdmin{}
	_ pact.AdminPermissioned = usersAdmin{}
	_ pact.AdminRecordSource = usersAdmin{}
	_ pact.FormRecordTitle   = usersAdmin{}
	_ FieldRelationProvider  = usersAdmin{}
)

func (usersAdmin) ID() string { return AdministratorsControllerID }

func (usersAdmin) ModelName() string { return BackendUserMorphType }

func (usersAdmin) ConfigDir() string { return "controllers/users" }

func (usersAdmin) RequiredPermissions() []string { return []string{PermissionManageUsers} }

func (usersAdmin) NewRecord() any { return &BackendUser{} }

// application is the activating app, or nil.
func (c usersAdmin) application() *backpack.App { return c.screens.application() }

// registry is the compiled registry, or nil before compilation finished.
func (c usersAdmin) registry() *Registry { return c.screens.registry() }

// FormRecordTitle names an administrator "First Last" when either name is
// set, otherwise by the login.
func (usersAdmin) FormRecordTitle(_ context.Context, _ *gorm.DB, record any) (string, error) {
	user, ok := record.(*BackendUser)
	if !ok || user == nil {
		return "", errors.New("cabana: administrators: record is not a backend user")
	}
	if name := strings.TrimSpace(strings.TrimSpace(user.FirstName) + " " + strings.TrimSpace(user.LastName)); name != "" {
		return name, nil
	}
	return user.Login, nil
}

// AdminFieldRelations binds the role picker. role_id is a protected column,
// so the contract opts in to writing it through this one field; the
// submitted id is still checked against the options and the role locks.
func (usersAdmin) AdminFieldRelations() []FieldRelationContract {
	return []FieldRelationContract{{
		Field:              "role",
		Kind:               "belongsTo",
		NewRelated:         func() any { return &BackendUserRole{} },
		ForeignKey:         "role_id",
		LabelColumn:        "name",
		WritableForeignKey: true,
	}}
}