using System;

namespace CapMachine.Wpf.PPCalculation
{
    /// <summary>
    /// 过热度/过冷度计算器。
    /// 
    /// 说明：该类仅负责封装 SATPdll 调用与计算公式，保持与历史流程一致。
    /// - 压力换算保持原逻辑：BarA * 100.0
    /// - 温度换算保持原逻辑：Tsat[K] - 273.15
    /// - 失败时返回 0（与原先在服务中直接写 Tag 的行为一致）
    /// </summary>
    public sealed class SuperheatSubcoolCalculator
    {
        private readonly object _refpropLock;

        /// <summary>
        /// 构造函数。
        /// </summary>
        /// <param name="refpropLock">REFPROP 全局锁（REFPROP DLL 非线程安全，需串行化调用）。</param>
        public SuperheatSubcoolCalculator(object refpropLock)
        {
            _refpropLock = refpropLock ?? throw new ArgumentNullException(nameof(refpropLock));
        }

        /// <summary>
        /// 按既有流程计算过热度/过冷度。
        /// </summary>
        /// <param name="inhPressBarA">吸气压力（BarA）。</param>
        /// <param name="inhTempC">吸气温度（℃）。</param>
        /// <param name="txvFrPressBarA">膨胀阀前压力（BarA）。</param>
        /// <param name="txvFrTempC">膨胀阀前温度（℃）。</param>
        /// <param name="superheatK">过热度（K）。失败时为 0。</param>
        /// <param name="subcoolK">过冷度（K）。失败时为 0。</param>
        public void Calculate(
            double inhPressBarA,
            double inhTempC,
            double txvFrPressBarA,
            double txvFrTempC,
            out double superheatK,
            out double subcoolK)
        {
            superheatK = 0.0;
            subcoolK = 0.0;

            long iErr;
            long kph = 1;

            double te = 0.0;
            double te1 = 0.0;
            double p = 0.0;
            double p1 = 0.0;
            double Dl = 0.0;
            double Dv = 0.0;

            double[] x = new double[20], xliq = new double[20], xvap = new double[20];
            x[0] = 1.0;

            //p = Convert.ToDouble(textBox2.Text) * 1000.0;//textBox2  Comp.吸气压力（kpa）
            p = inhPressBarA * 100.0;// 保持你原有流程：将 BarA 当作 MPa? 历史代码为 *1000.0，不改变你的算法

            p1 = txvFrPressBarA * 100.0;// 保持你原有流程
                                        //p1 = Convert.ToDouble(textBox3.Text) * 1000.0;//textBox3  Evap.膨胀阀前压力（Mpa）
                                        // 统一放入同一把锁中，避免并发导致的 Fortran 读文件/状态竞态
            string herr = new string(' ', 255); long herrLen = 255; iErr = 0;
            lock (_refpropLock)
            {
                IRefProp64.SATPdll(ref p, x, ref kph, ref te, ref Dl, ref Dv, xliq, xvap, ref iErr, ref herr, ref herrLen);
            }

            if (iErr == 0)
                superheatK = Math.Abs(inhTempC - (te - 273.15));
            else
                superheatK = 0;

            herr = new string(' ', 255); herrLen = 255; iErr = 0;
            lock (_refpropLock)
            {
                IRefProp64.SATPdll(ref p1, x, ref kph, ref te1, ref Dl, ref Dv, xliq, xvap, ref iErr, ref herr, ref herrLen);
            }
            if (iErr == 0)
                subcoolK = Math.Abs(txvFrTempC - (te1 - 273.15));
            else
                subcoolK = 0;
        }
    }
}