using System.Reflection.Metadata;
using System.Reflection.PortableExecutable;
using System.Security.Cryptography;
using Newtonsoft.Json;

static class PrecompiledAudit
{
    internal static int Run()
    {
        var root=Path.GetFullPath(Path.Combine(AppContext.BaseDirectory,"../../../../../.."));
        if(!Directory.Exists(Path.Combine(root,"Client/Assets"))) throw new InvalidOperationException("Project root required.");
        var files=new[]{"Client/Assets","Client/Packages","Client/LocalPackages","Client/Library/PackageCache"}.SelectMany(p=>Directory.Exists(Path.Combine(root,p)) ?
            Directory.EnumerateFiles(Path.Combine(root,p),"*.dll",SearchOption.AllDirectories) : Array.Empty<string>()).OrderBy(p=>p,StringComparer.Ordinal).ToArray();
        var rows=new List<object>(); int blocked=0,managed=0,native=0;
        foreach(var file in files)
        {
            string kind="managed"; var references=new List<string>(); var assemblies=new List<string>();
            using var stream=File.OpenRead(file);
            try
            {
                using var pe=new PEReader(stream);
                if(!pe.HasMetadata) { native++; kind="native"; }
                else
                {
                    managed++; var reader=pe.GetMetadataReader();
                    foreach(var h in reader.AssemblyReferences)
                    { var name=reader.GetString(reader.GetAssemblyReference(h).Name); if(name=="HotUpdate") assemblies.Add(name); }
                    foreach(var h in reader.MemberReferences)
                    {
                        var member=reader.GetMemberReference(h); string name=reader.GetString(member.Name);
                        if(name!="BuilderCapacity" || member.Parent.Kind!=HandleKind.TypeReference) continue;
                        var t=reader.GetTypeReference((TypeReferenceHandle)member.Parent);
                        if(reader.GetString(t.Namespace)=="EventPartnerGather" && reader.GetString(t.Name)=="PartnerInfoManager") references.Add("EventPartnerGather.PartnerInfoManager.BuilderCapacity");
                    }
                    if(references.Count>0) blocked++;
                }
            }
            catch(BadImageFormatException) { kind="unreadable-PE"; blocked++; }
            rows.Add(new { path=Path.GetRelativePath(root,file).Replace('\\','/'),sha256=Convert.ToHexString(SHA256.HashData(File.ReadAllBytes(file))),kind,fieldReferences=references,hotUpdateReferences=assemblies });
        }
        var report=new { success=blocked==0,scope="Assets-Packages-LocalPackages-PackageCache-dlls",total=files.Length,managed,native,blocked,files=rows };
        File.WriteAllText(Path.Combine(root,"CodexOutput/upserver/KVGameLoadTests/checkpoint2-D4-precompiled-audit.json"),JsonConvert.SerializeObject(report,Formatting.Indented));
        Console.WriteLine($"PRECOMPILED total={files.Length} managed={managed} native={native} blocked={blocked}");
        return blocked==0 ? 0 : 1;
    }
}