sharpemu/src/SharpEmu.Libs/Json/JsonValueExports.cs

// Copyright (C) 2026 SharpEmu Emulator Project
// SPDX-License-Identifier: GPL-2.0-or-later

using SharpEmu.HLE;

namespace SharpEmu.Libs.Json;

// sce::Json::Value and sce::Json::String constructors, setters and destructors. Prospero titles
// (Quake among them) build a Value tree and populate it through these before serializing it for a
// web request; without them the imports resolve to nothing and the guest faults on the call. The
// payload is modelled in JsonObjectHeap; here we only translate the C++ ABI (registers in, `this`
// back out) and never write the guest object, so a stack-allocated Value/String is left intact.
//
// Only the complete-object variants (C1/D1) are bound — those are what standalone locals emit and
// what the observed Prospero imports use. The base-object variants (C2/D2) are left for a title
// that actually imports them.
public static class JsonValueExports
{
    private const int MaxStringLength = 0x10000;

    private static int ReturnThis(CpuContext ctx, ulong thisAddress)
    {
        ctx[CpuRegister.Rax] = thisAddress;
        return (int)OrbisGen2Result.ORBIS_GEN2_OK;
    }

    private static int ReturnVoid(CpuContext ctx)
    {
        ctx[CpuRegister.Rax] = 0;
        return (int)OrbisGen2Result.ORBIS_GEN2_OK;
    }

    private static double ReadDoubleArg(CpuContext ctx)
    {
        ctx.GetXmmRegister(0, out var low, out _);
        return BitConverter.Int64BitsToDouble(unchecked((long)low));
    }

    private static string ReadCString(CpuContext ctx, ulong address) =>
        ctx.TryReadNullTerminatedUtf8(address, MaxStringLength, out var text) ? text : string.Empty;

    // ---- sce::Json::Value constructors ----

    [SysAbiExport(Nid = "qBMjqyBn3OM", ExportName = "_ZN3sce4Json5ValueC1Ev",
        Target = Generation.Gen4 | Generation.Gen5, LibraryName = "libSceJson")]
    public static int ValueDefaultConstructor(CpuContext ctx)
    {
        var thisAddress = ctx[CpuRegister.Rdi];
        JsonObjectHeap.SetValue(thisAddress, JsonValueState.Null);
        return ReturnThis(ctx, thisAddress);
    }

    [SysAbiExport(Nid = "UeuWT+yNdCQ", ExportName = "_ZN3sce4Json5ValueC1Eb",
        Target = Generation.Gen4 | Generation.Gen5, LibraryName = "libSceJson")]
    public static int ValueBooleanConstructor(CpuContext ctx)
    {
        var thisAddress = ctx[CpuRegister.Rdi];
        JsonObjectHeap.SetValue(thisAddress, JsonValueState.FromBoolean((ctx[CpuRegister.Rsi] & 0xFF) != 0));
        return ReturnThis(ctx, thisAddress);
    }

    [SysAbiExport(Nid = "0lLK8+kDqmE", ExportName = "_ZN3sce4Json5ValueC1El",
        Target = Generation.Gen4 | Generation.Gen5, LibraryName = "libSceJson")]
    public static int ValueIntegerConstructor(CpuContext ctx)
    {
        var thisAddress = ctx[CpuRegister.Rdi];
        JsonObjectHeap.SetValue(thisAddress, JsonValueState.FromInteger(unchecked((long)ctx[CpuRegister.Rsi])));
        return ReturnThis(ctx, thisAddress);
    }

    [SysAbiExport(Nid = "x4AUdbhpRB0", ExportName = "_ZN3sce4Json5ValueC1Em",
        Target = Generation.Gen4 | Generation.Gen5, LibraryName = "libSceJson")]
    public static int ValueUnsignedConstructor(CpuContext ctx)
    {
        var thisAddress = ctx[CpuRegister.Rdi];
        JsonObjectHeap.SetValue(thisAddress, JsonValueState.FromUnsignedInteger(ctx[CpuRegister.Rsi]));
        return ReturnThis(ctx, thisAddress);
    }

    [SysAbiExport(Nid = "sOmU4vnx3s0", ExportName = "_ZN3sce4Json5ValueC1Ed",
        Target = Generation.Gen4 | Generation.Gen5, LibraryName = "libSceJson")]
    public static int ValueRealConstructor(CpuContext ctx)
    {
        var thisAddress = ctx[CpuRegister.Rdi];
        JsonObjectHeap.SetValue(thisAddress, JsonValueState.FromReal(ReadDoubleArg(ctx)));
        return ReturnThis(ctx, thisAddress);
    }

    [SysAbiExport(Nid = "b9V6fmppLXY", ExportName = "_ZN3sce4Json5ValueC1EPKc",
        Target = Generation.Gen4 | Generation.Gen5, LibraryName = "libSceJson")]
    public static int ValueCStringConstructor(CpuContext ctx)
    {
        var thisAddress = ctx[CpuRegister.Rdi];
        JsonObjectHeap.SetValue(thisAddress, JsonValueState.FromString(ReadCString(ctx, ctx[CpuRegister.Rsi])));
        return ReturnThis(ctx, thisAddress);
    }

    [SysAbiExport(Nid = "CbrT3dwDILo", ExportName = "_ZN3sce4Json5ValueC1ENS0_9ValueTypeE",
        Target = Generation.Gen4 | Generation.Gen5, LibraryName = "libSceJson")]
    public static int ValueTypeConstructor(CpuContext ctx)
    {
        var thisAddress = ctx[CpuRegister.Rdi];
        JsonObjectHeap.SetValue(thisAddress, JsonValueState.FromExplicitType(unchecked((uint)ctx[CpuRegister.Rsi])));
        return ReturnThis(ctx, thisAddress);
    }

    [SysAbiExport(Nid = "sZIoMRGO+jk", ExportName = "_ZN3sce4Json5ValueC1ERKNS0_6StringE",
        Target = Generation.Gen4 | Generation.Gen5, LibraryName = "libSceJson")]
    public static int ValueStringConstructor(CpuContext ctx)
    {
        var thisAddress = ctx[CpuRegister.Rdi];
        JsonObjectHeap.SetValue(thisAddress, JsonValueState.FromString(JsonObjectHeap.GetStringOrEmpty(ctx[CpuRegister.Rsi])));
        return ReturnThis(ctx, thisAddress);
    }

    [SysAbiExport(Nid = "WTtYf+cNnXI", ExportName = "_ZN3sce4Json5ValueD1Ev",
        Target = Generation.Gen4 | Generation.Gen5, LibraryName = "libSceJson")]
    public static int ValueDestructor(CpuContext ctx)
    {
        JsonObjectHeap.RemoveValue(ctx[CpuRegister.Rdi]);
        return ReturnVoid(ctx);
    }

    // ---- sce::Json::Value setters (return Value&, i.e. `this`) ----

    [SysAbiExport(Nid = "5yHuiWXo2gg", ExportName = "_ZN3sce4Json5Value3setEb",
        Target = Generation.Gen4 | Generation.Gen5, LibraryName = "libSceJson")]
    public static int ValueSetBoolean(CpuContext ctx)
    {
        var thisAddress = ctx[CpuRegister.Rdi];
        JsonObjectHeap.SetValue(thisAddress, JsonValueState.FromBoolean((ctx[CpuRegister.Rsi] & 0xFF) != 0));
        return ReturnThis(ctx, thisAddress);
    }

    [SysAbiExport(Nid = "QxVVYhP-mvg", ExportName = "_ZN3sce4Json5Value3setEl",
        Target = Generation.Gen4 | Generation.Gen5, LibraryName = "libSceJson")]
    public static int ValueSetInteger(CpuContext ctx)
    {
        var thisAddress = ctx[CpuRegister.Rdi];
        JsonObjectHeap.SetValue(thisAddress, JsonValueState.FromInteger(unchecked((long)ctx[CpuRegister.Rsi])));
        return ReturnThis(ctx, thisAddress);
    }

    [SysAbiExport(Nid = "SIe1ZmW7e7s", ExportName = "_ZN3sce4Json5Value3setEm",
        Target = Generation.Gen4 | Generation.Gen5, LibraryName = "libSceJson")]
    public static int ValueSetUnsigned(CpuContext ctx)
    {
        var thisAddress = ctx[CpuRegister.Rdi];
        JsonObjectHeap.SetValue(thisAddress, JsonValueState.FromUnsignedInteger(ctx[CpuRegister.Rsi]));
        return ReturnThis(ctx, thisAddress);
    }

    [SysAbiExport(Nid = "BSmWDIkV4w4", ExportName = "_ZN3sce4Json5Value3setEd",
        Target = Generation.Gen4 | Generation.Gen5, LibraryName = "libSceJson")]
    public static int ValueSetReal(CpuContext ctx)
    {
        var thisAddress = ctx[CpuRegister.Rdi];
        JsonObjectHeap.SetValue(thisAddress, JsonValueState.FromReal(ReadDoubleArg(ctx)));
        return ReturnThis(ctx, thisAddress);
    }

    [SysAbiExport(Nid = "IKQimvG9Wqs", ExportName = "_ZN3sce4Json5Value3setENS0_9ValueTypeE",
        Target = Generation.Gen4 | Generation.Gen5, LibraryName = "libSceJson")]
    public static int ValueSetType(CpuContext ctx)
    {
        var thisAddress = ctx[CpuRegister.Rdi];
        JsonObjectHeap.SetValue(thisAddress, JsonValueState.FromExplicitType(unchecked((uint)ctx[CpuRegister.Rsi])));
        return ReturnThis(ctx, thisAddress);
    }

    [SysAbiExport(Nid = "n6FC+l9DU70", ExportName = "_ZN3sce4Json5Value3setEPKc",
        Target = Generation.Gen4 | Generation.Gen5, LibraryName = "libSceJson")]
    public static int ValueSetCString(CpuContext ctx)
    {
        var thisAddress = ctx[CpuRegister.Rdi];
        JsonObjectHeap.SetValue(thisAddress, JsonValueState.FromString(ReadCString(ctx, ctx[CpuRegister.Rsi])));
        return ReturnThis(ctx, thisAddress);
    }

    [SysAbiExport(Nid = "6l3Bv2gysNc", ExportName = "_ZN3sce4Json5Value3setERKNS0_6StringE",
        Target = Generation.Gen4 | Generation.Gen5, LibraryName = "libSceJson")]
    public static int ValueSetString(CpuContext ctx)
    {
        var thisAddress = ctx[CpuRegister.Rdi];
        JsonObjectHeap.SetValue(thisAddress, JsonValueState.FromString(JsonObjectHeap.GetStringOrEmpty(ctx[CpuRegister.Rsi])));
        return ReturnThis(ctx, thisAddress);
    }

    [SysAbiExport(Nid = "FIjXN2TkuTs", ExportName = "_ZN3sce4Json5Value5clearEv",
        Target = Generation.Gen4 | Generation.Gen5, LibraryName = "libSceJson")]
    public static int ValueClear(CpuContext ctx)
    {
        var thisAddress = ctx[CpuRegister.Rdi];
        JsonObjectHeap.SetValue(thisAddress, JsonValueState.Null);
        return ReturnThis(ctx, thisAddress);
    }

    // ---- sce::Json::String ----

    [SysAbiExport(Nid = "9KUZFjI1IxA", ExportName = "_ZN3sce4Json6StringC1EPKc",
        Target = Generation.Gen4 | Generation.Gen5, LibraryName = "libSceJson")]
    public static int StringCStringConstructor(CpuContext ctx)
    {
        var thisAddress = ctx[CpuRegister.Rdi];
        JsonObjectHeap.SetString(thisAddress, ReadCString(ctx, ctx[CpuRegister.Rsi]));
        return ReturnThis(ctx, thisAddress);
    }

    [SysAbiExport(Nid = "qSmqLXXCPas", ExportName = "_ZN3sce4Json6StringC1Ev",
        Target = Generation.Gen4 | Generation.Gen5, LibraryName = "libSceJson")]
    public static int StringDefaultConstructor(CpuContext ctx)
    {
        var thisAddress = ctx[CpuRegister.Rdi];
        JsonObjectHeap.SetString(thisAddress, string.Empty);
        return ReturnThis(ctx, thisAddress);
    }

    [SysAbiExport(Nid = "0CAesfH963Q", ExportName = "_ZN3sce4Json6StringC1ERKS1_",
        Target = Generation.Gen4 | Generation.Gen5, LibraryName = "libSceJson")]
    public static int StringCopyConstructor(CpuContext ctx)
    {
        var thisAddress = ctx[CpuRegister.Rdi];
        JsonObjectHeap.SetString(thisAddress, JsonObjectHeap.GetStringOrEmpty(ctx[CpuRegister.Rsi]));
        return ReturnThis(ctx, thisAddress);
    }

    [SysAbiExport(Nid = "cG1VE2HMl6c", ExportName = "_ZN3sce4Json6StringD1Ev",
        Target = Generation.Gen4 | Generation.Gen5, LibraryName = "libSceJson")]
    public static int StringDestructor(CpuContext ctx)
    {
        JsonObjectHeap.RemoveString(ctx[CpuRegister.Rdi]);
        return ReturnVoid(ctx);
    }
}