namespace ScadaLink.InboundAPI.Tests;

/// <summary>
/// InboundAPI-005 / InboundAPI-015: tests for the script-trust-model checker.
///
/// InboundAPI-015 hardens the textual walker against reflection reached through
/// permitted-type members that never spell a forbidden namespace, e.g.
/// <c>typeof(string).Assembly.GetType("System.IO.File")</c>.
/// </summary>
public class ForbiddenApiCheckerTests
{
    private static bool IsRejected(string script) =>
        ForbiddenApiChecker.FindViolations(script).Count > 0;

    // --- Baseline: legitimate scripts must still pass ---

    [Theory]
    [InlineData("return 1 + 1;")]
    [InlineData("var list = new List<int> { 1, 2, 3 }; return list.Sum();")]
    [InlineData("return Parameters.Get<int>(\"x\") * 2;")]
    [InlineData("await Task.Delay(1); return null;")]
    [InlineData("var r = await Route.To(\"inst\").Call(\"s\"); return r;")]
    [InlineData("Action a = () => {}; a.Invoke(); return null;")]
    public void PermittedScript_NotRejected(string script)
    {
        Assert.False(IsRejected(script), script);
    }

    // --- Baseline: forbidden namespaces (textual) must still be rejected ---

    [Theory]
    [InlineData("System.IO.File.Delete(\"/tmp/x\"); return null;")]
    [InlineData("System.Diagnostics.Process.Start(\"/bin/sh\"); return null;")]
    [InlineData("using System.Reflection; return null;")]
    [InlineData("var s = new System.Net.Sockets.Socket(default, default, default); return null;")]
    public void ForbiddenNamespace_Rejected(string script)
    {
        Assert.True(IsRejected(script), script);
    }

    // --- InboundAPI-015: reflection reachable without a forbidden namespace token ---

    [Fact]
    public void Reflection_AssemblyPropertyAccess_Rejected()
    {
        // typeof(string).Assembly — .Assembly is a reflection gateway off a permitted type.
        Assert.True(IsRejected("var a = typeof(string).Assembly; return null;"));
    }

    [Fact]
    public void Reflection_AssemblyGetType_Rejected()
    {
        // The classic bypass: obtain System.IO.File as a Type via a string literal.
        Assert.True(IsRejected(
            "var t = typeof(string).Assembly.GetType(\"System.IO.File\"); return null;"));
    }

    [Fact]
    public void Reflection_ObjectGetType_Rejected()
    {
        // x.GetType() returns a System.Type — a reflection gateway.
        Assert.True(IsRejected("var t = \"\".GetType(); return null;"));
    }

    [Fact]
    public void Reflection_TypeGetTypeStatic_Rejected()
    {
        Assert.True(IsRejected("var t = Type.GetType(\"System.IO.File\"); return null;"));
    }

    [Fact]
    public void Reflection_ActivatorCreateInstance_Rejected()
    {
        Assert.True(IsRejected(
            "var o = Activator.CreateInstance(Type.GetType(\"System.IO.File\")); return null;"));
    }

    [Fact]
    public void Reflection_InvokeMember_Rejected()
    {
        Assert.True(IsRejected(
            "typeof(object).InvokeMember(\"x\", default, null, null, null); return null;"));
    }

    [Fact]
    public void Reflection_GetMethodInvoke_Rejected()
    {
        Assert.True(IsRejected(
            "var m = typeof(object).GetMethod(\"ToString\"); return null;"));
    }

    [Fact]
    public void Reflection_GetTypeInfo_Rejected()
    {
        Assert.True(IsRejected("var ti = \"\".GetType().GetTypeInfo(); return null;"));
    }

    [Fact]
    public void DynamicKeyword_Rejected()
    {
        // dynamic widens late-bound member access the static walker cannot see through.
        Assert.True(IsRejected("dynamic d = Parameters; return null;"));
    }
}
