using System;
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using System.Collections.Generic;
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using System.Globalization;
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using DPumpHydr.WinFrmUI.WenSkin.Json.Utilities;
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namespace DPumpHydr.WinFrmUI.WenSkin.Json.Linq.JsonPath
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{
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internal class ArraySliceFilter : PathFilter
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{
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public int? Start { get; set; }
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public int? End { get; set; }
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public int? Step { get; set; }
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public override IEnumerable<JToken> ExecuteFilter(IEnumerable<JToken> current, bool errorWhenNoMatch)
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{
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if (Step == 0)
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{
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throw new JsonException("Step cannot be zero.");
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}
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foreach (JToken t in current)
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{
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JArray a = t as JArray;
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if (a != null)
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{
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int stepCount = Step ?? 1;
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int num = Start ?? ((stepCount <= 0) ? (a.Count - 1) : 0);
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int stopIndex3 = End ?? ((stepCount > 0) ? a.Count : (-1));
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if (Start < 0)
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{
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num = a.Count + num;
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}
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if (End < 0)
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{
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stopIndex3 = a.Count + stopIndex3;
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}
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num = Math.Max(num, (stepCount <= 0) ? int.MinValue : 0);
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num = Math.Min(num, (stepCount > 0) ? a.Count : (a.Count - 1));
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stopIndex3 = Math.Max(stopIndex3, -1);
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stopIndex3 = Math.Min(stopIndex3, a.Count);
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bool positiveStep = stepCount > 0;
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if (IsValid(num, stopIndex3, positiveStep))
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{
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for (int i = num; IsValid(i, stopIndex3, positiveStep); i += stepCount)
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{
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yield return a[i];
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}
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}
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else if (errorWhenNoMatch)
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{
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throw new JsonException("Array slice of {0} to {1} returned no results.".FormatWith(CultureInfo.InvariantCulture, Start.HasValue ? Start.GetValueOrDefault().ToString(CultureInfo.InvariantCulture) : "*", End.HasValue ? End.GetValueOrDefault().ToString(CultureInfo.InvariantCulture) : "*"));
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}
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}
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else if (errorWhenNoMatch)
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{
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throw new JsonException("Array slice is not valid on {0}.".FormatWith(CultureInfo.InvariantCulture, t.GetType().Name));
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}
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}
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}
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private bool IsValid(int index, int stopIndex, bool positiveStep)
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{
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if (positiveStep)
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{
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return index < stopIndex;
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}
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return index > stopIndex;
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}
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}
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}
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