using System;
using IwbZero.Expr;
using IwbZero.ToolCommon.StringModel;

namespace IwbZero.ExprFunctions.Functions
{
    /// <summary>
    /// 获取日期（年-月-01）
    /// </summary>
    public class FunGetFdm:IIwbFunction
    {
        public string Invoke(ExprObject exprObj)
        {
            DateTime now = DateTime.Now;
            int num = now.Year;
            now = DateTime.Now;
            int num2 = now.Month;
            ExprObject child = exprObj.GetChild(0);
            if (child != null)
            {
                ExprTypes exprTypes = EvalExpr.GetExprTypes(child);
                if (exprTypes == ExprTypes.Date || exprTypes == ExprTypes.String)
                {
                    DateTime dateTime = child.Expr.StrToDt();
                    num = dateTime.Year;
                    num2 = dateTime.Month;
                }
                else
                {
                    num = child.Expr.ValI();
                    if (num == 0)
                    {
                        now = DateTime.Now;
                        num = now.Year;
                    }
                    child = exprObj.GetChild(2);
                    if (child != null)
                    {
                        num2 = child.Expr.ValI();
                    }
                    if (num2 == 0)
                    {
                        now = DateTime.Now;
                        num2 = now.Month;
                    }
                }
            }
            return $"{num}-{num2}-01";
        }
    }
}