using System.Collections.Generic;
using System.Linq;

namespace IStation.Model
{
    /// <summary>
    /// 特性曲线辅助类
    /// </summary>
    public class FeatCurveHelper
    {

        /// <summary>
        /// 通过 频率 计算流量扬程曲线表达式
        /// </summary>
        public static CurveExpress CalcuCurveQhByHz(Model.CurveExpress curve, double hz)
        {
            if (curve == null)
                return default;
            var points = curve.GetFitPoints(20);
            return CalcuCurveQhByHz(points, curve.FitType, hz);
        }

        /// <summary>
        /// 通过 频率 计算流量扬程曲线表达式
        /// </summary>
        public static CurveExpress CalcuCurveQhByHz(List<CurvePoint> pts, eCurveFitType fit, double hz)
        {
            if (pts == null)
                return default;
            var fit_pow = CurveExpress.GetFitPow(fit);
            if (pts.Count < fit_pow + 1)
                return default;
            double f_ratio = hz / 50.0;
            var list = pts.Select(x => new CurvePoint(x.X * f_ratio, x.Y * f_ratio * f_ratio)).ToList();
            return new CurveExpress(list, fit);
            //return new CurveExpress(pts, fit);
        }

        /// <summary>
        /// 通过 频率 计算流量功率曲线表达式
        /// </summary>
        public static CurveExpress CalcuCurveQpByHz(Model.CurveExpress curve, double hz)
        {
            if (curve == null)
                return default;
            var points = curve.GetFitPoints(20);
            return CalcuCurveQpByHz(points, curve.FitType, hz);
        }

        /// <summary>
        /// 通过 频率 计算流量功率曲线表达式
        /// </summary>
        public static CurveExpress CalcuCurveQpByHz(List<CurvePoint> pts, eCurveFitType fit, double hz)
        {
            if (pts == null)
                return default;
            var fit_pow = CurveExpress.GetFitPow(fit);
            if (pts.Count < fit_pow + 1)
                return default;
            double f_ratio = hz / 50.0;
            var list = pts.Select(x => new CurvePoint(x.X * f_ratio, x.Y * f_ratio * f_ratio * f_ratio)).ToList();
            return new CurveExpress(list, fit);
        }



    }
}