add comprehensive delete, fix bug in changeparent

categories/categories.go

@@ -5,6 +5,7 @@ import (
 	_ "github.com/lib/pq"
 	"fmt"
 	"strings"
+	"errors"
 )
 
 type Category struct {
@@ -61,9 +62,42 @@ func Add(db *sql.DB, name string, parent int) error {
 	return err
 }
 
+// Get parent id
+//  Set parent of children to parent
+//  set category of news to parent
+//  finallly delete
 func Delete(db *sql.DB, id int) error {
+    rows, err := db.Query("SELECT parent_id FROM categories WHERE id=$1", id)
+    if err != nil  {
+        fmt.Println("Categories DB Error loading category parent id: ", err)
+        return err
+    }
     
-    return nil
+    if !rows.Next() {
+        fmt.Println("Categories DB Error loading category parent id: no category")
+        return errors.New("No category")
+    } 
+	var parent_id sql.NullInt64
+	err = rows.Scan(&parent_id)
+	
+    _, err = db.Exec("UPDATE categories SET parent_id =$2 WHERE parent_id=$1", id, parent_id)
+    if err != nil {
+        fmt.Println("Categories DB error changing child parent: ", err)
+        return err
+    }
+    
+   
+    _, err = db.Exec("UPDATE news SET category_id =$2 WHERE category_id=$1", id, parent_id)
+   if err != nil {
+        fmt.Println("Categories DB error changing category of news: ", err)
+        return err
+    }
+
+    _, err = db.Exec("DELETE FROM categories WHERE id=$1", id)
+    if err != nil {
+        fmt.Println("Categories DB Error Delete(): ", err)
+    }
+    return err
 }
 
 func (category *Category) ChangeParent(db *sql.DB, parent *Category) error {

route_handlers.go

@@ -266,6 +266,8 @@ func categoryChangeParentHandler(w http.ResponseWriter, r *http.Request, user *u
 	
 	if category == nil {
 		session.AddFlash("Invalid category", flash_err)	
+	} else if parent != nil && category.Id == parent.Id { 
+		session.AddFlash("Cannot set category parent to itself", flash_err)
 	} else {
 	    err := category.ChangeParent(db, parent)
 	    if err != nil {