XFEEDToolBox

using System.Text.Json;

namespace XFEEDToolBox.Core.Navigation;

/// <summary>Recognizes a completed optional SCO refusal without weakening primary flight checks.</summary>
public static class ScoStartRefusal
{
    public static bool CanContinueOrdinaryFlight(JsonElement status,JsonElement receipt,string owner,string requestId,ulong generation,ulong selection,
        SystemFlightFrame flight,DateTimeOffset now)
    {
        static bool Is(JsonElement e,string key,JsonValueKind kind)=>e.ValueKind==JsonValueKind.Object&&e.TryGetProperty(key,out var v)&&v.ValueKind==kind;
        static string? Text(JsonElement e,string key)=>Is(e,key,JsonValueKind.String)?e.GetProperty(key).GetString():null;
        static ulong Id(JsonElement e,string key)=>ulong.TryParse(Text(e,key),out var value)?value:0;
        static bool Number(JsonElement e,string key,ulong expected)=>Is(e,key,JsonValueKind.Number)&&e.GetProperty(key).TryGetUInt64(out var value)&&value==expected;
        if(!flight.InGame||!flight.GeometryVerified||flight.PlayerOverride||flight.ExternalThreat||flight.Mode!=LocalFlightMode.Supercruise||flight.ShipEntity==0||flight.ReferenceWorld==0
            ||flight.ObservedAt>now||now-flight.ObservedAt>TimeSpan.FromMilliseconds(300)||string.IsNullOrEmpty(owner)||string.IsNullOrEmpty(requestId)
            ||!Is(status,"owned",JsonValueKind.False)||!Is(receipt,"failed",JsonValueKind.True)||!Is(receipt,"applied",JsonValueKind.False)
            ||!Is(receipt,"nativeMethodCalled",JsonValueKind.False)||Text(receipt,"owner")!=owner||Text(receipt,"requestId")!=requestId
            ||generation==0||selection==0||!Number(receipt,"generation",generation)||!Number(receipt,"selectionGeneration",selection)
            ||Text(receipt,"reason") is not("geometry-or-assist" or "approach-or-alignment" or "native-refusal" or "fuel" or "heat" or "thermal-model")
            ||!status.TryGetProperty("sample",out var sample)||sample.ValueKind!=JsonValueKind.Object
            ||Id(sample,"entityId")!=flight.ShipEntity||Id(sample,"referenceWorldAddress")!=flight.ReferenceWorld
            ||!Is(sample,"verified",JsonValueKind.True)||!Is(sample,"inSupercruise",JsonValueKind.True)||!Is(sample,"stableFsd",JsonValueKind.True)
            ||!Number(sample,"rawFsdState",2)||!Is(sample,"playerOverride",JsonValueKind.False)||!Is(sample,"state",JsonValueKind.Number)
            ||!sample.GetProperty("state").TryGetInt32(out var stateId)||stateId is not(0 or 3)
            ||!Is(sample,"observedAtUnixMilliseconds",JsonValueKind.Number)||!sample.GetProperty("observedAtUnixMilliseconds").TryGetInt64(out var milliseconds)
            ||milliseconds>now.ToUnixTimeMilliseconds()||milliseconds<now.ToUnixTimeMilliseconds()-200
            ||!receipt.TryGetProperty("gate",out var gate)||!Is(gate,"identityVerified",JsonValueKind.True)||!Is(gate,"targetVerified",JsonValueKind.True)
            ||!Is(gate,"emergency",JsonValueKind.False)||!Is(gate,"damageSeen",JsonValueKind.False)||!Is(gate,"assistEnabled",JsonValueKind.False)
            ||!Is(gate,"hullFraction",JsonValueKind.Number)||!gate.GetProperty("hullFraction").TryGetDouble(out var fraction)||!double.IsFinite(fraction)||fraction is <=0 or >1)return false;
        return true;
    }
}