1 files changed, 69 insertions, 0 deletions
diff --git a/docker/crupest-api/CrupestApi/CrupestApi.Commons/Crud/ColumnInfo.cs b/docker/crupest-api/CrupestApi/CrupestApi.Commons/Crud/ColumnInfo.cs
new file mode 100644
index 0000000..8b4607d
--- /dev/null
+++ b/docker/crupest-api/CrupestApi/CrupestApi.Commons/Crud/ColumnInfo.cs
@@ -0,0 +1,69 @@
+using System.Reflection;
+
+namespace CrupestApi.Commons.Crud;
+
+public class ColumnInfo
+{
+    private Type ExtractRealTypeFromNullable(Type type)
+    {
+        if (type.IsGenericType && type.GetGenericTypeDefinition() == typeof(Nullable<>))
+        {
+            return type.GetGenericArguments()[0];
+        }
+
+        return type;
+    }
+
+    // A column with no property.
+    public ColumnInfo(Type entityType, string sqlColumnName, bool isPrimaryKey, bool isAutoIncrement, IColumnTypeInfo typeInfo)
+    {
+        EntityType = entityType;
+        PropertyName = null;
+        PropertyType = typeof(int);
+        PropertyRealType = typeof(int);
+        SqlColumnName = sqlColumnName;
+        ColumnTypeInfo = typeInfo;
+        Nullable = false;
+        IsPrimaryKey = isPrimaryKey;
+        IsAutoIncrement = isAutoIncrement;
+    }
+
+    public ColumnInfo(Type entityType, string entityPropertyName)
+    {
+        EntityType = entityType;
+        PropertyName = entityPropertyName;
+
+        var property = entityType.GetProperty(entityPropertyName);
+
+        if (property is null)
+            throw new Exception("Public property with given name does not exist.");
+
+        PropertyType = property.PropertyType;
+        PropertyRealType = ExtractRealTypeFromNullable(PropertyType);
+
+        var columnAttribute = property.GetCustomAttribute<ColumnAttribute>();
+        if (columnAttribute is null)
+        {
+            SqlColumnName = PropertyName;
+            Nullable = true;
+        }
+        else
+        {
+            SqlColumnName = columnAttribute.DatabaseName ?? PropertyName;
+            Nullable = !columnAttribute.NonNullable;
+        }
+        ColumnTypeInfo = ColumnTypeInfoRegistry.Singleton.GetRequiredByDataType(PropertyRealType);
+
+    }
+
+    public Type EntityType { get; }
+    // If null, there is no corresponding property.
+    public string? PropertyName { get; }
+    public Type PropertyType { get; }
+    public Type PropertyRealType { get; }
+    public string SqlColumnName { get; }
+    public IColumnTypeInfo ColumnTypeInfo { get; }
+    public bool Nullable { get; }
+    public bool IsPrimaryKey { get; }
+    public bool IsAutoIncrement { get; }
+}
+\ No newline at end of file