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

// Synthetic-shader conformance dumper.
//
// Feeds hand-assembled Gen5 (gfx10) instruction words through the real
// decode -> SPIR-V pipeline (Gen5ShaderTranslator / Gen5SpirvTranslator, via
// reflection so no emulator source changes are required) and writes the
// resulting vertex, pixel, and compute SPIR-V blobs to disk. The blobs can then be
// checked with spirv-val / spirv-dis.
//
// Programs that contain buffer_store_dword automatically get a single
// global-memory binding covering every store, which the emitter exposes as
// guestBuffers[0] (descriptor set 0, binding 0).
//
// Each program carries an expectation: ExpectTranslate=true programs must
// decode and emit the requested stages; ExpectTranslate=false programs pin a decode
// failure that must stay loud. Any unexpected outcome makes the tool exit
// non-zero, so it can gate scripts/CI.
//
// Usage: SharpEmu.Tools.ShaderDump [output-directory]

using System.Buffers.Binary;
using System.Reflection;
using SharpEmu.HLE;
using SharpEmu.Libs.CxxAbi;

const ulong ProgramAddress = 0x100000;

(string Name, bool ExpectTranslate, uint[] Words)[] testPrograms =
[
    ("fmac", true, [
        0x560A0501,             // v_fmac_f32 v5, v1, v2
        0x580A0501, 0x42280000, // v_fmamk_f32 v5, v1, 42.0, v2
        0x5A0A0501, 0x42280000, // v_fmaak_f32 v5, v1, v2, 42.0
        0xD52B0005, 0x00020501, // v_fmac_f32_e64 v5, v1, v2
        0xBF810000,             // s_endpgm
    ]),
    ("muls", true, [
        0xD5690005, 0x00020501, // v_mul_lo_u32 v5, v1, v2
        0xD56A0005, 0x00020501, // v_mul_hi_u32 v5, v1, v2
        0xD56B0005, 0x00020501, // v_mul_lo_i32 v5, v1, v2
        0xD56C0005, 0x00020501, // v_mul_hi_i32 v5, v1, v2
        0xBF810000,             // s_endpgm
    ]),
    ("mrt", true, [
        0x7E0002FF, 0x3F800000, // v_mov_b32 v0, 1.0f
        0x7E0202FF, 0x00000000, // v_mov_b32 v1, 0.0f
        0x7E0402FF, 0x00000000, // v_mov_b32 v2, 0.0f
        0x7E0602FF, 0x3F800000, // v_mov_b32 v3, 1.0f
        0x7E0802FF, 0x00000001, // v_mov_b32 v4, 1u
        0x7E0A02FF, 0x00000002, // v_mov_b32 v5, 2u
        0x7E0C02FF, 0x00000003, // v_mov_b32 v6, 3u
        0x7E0E02FF, 0x00000004, // v_mov_b32 v7, 4u
        0x7E1002FF, 0xFFFFFFFF, // v_mov_b32 v8, -1
        0x7E1202FF, 0x00000002, // v_mov_b32 v9, 2
        0x7E1402FF, 0xFFFFFFFD, // v_mov_b32 v10, -3
        0x7E1602FF, 0x00000004, // v_mov_b32 v11, 4
        0xF800000F, 0x03020100, // exp mrt0 v0, v1, v2, v3
        0xF800003F, 0x07060504, // exp mrt3 v4, v5, v6, v7
        0xF800086F, 0x0B0A0908, // exp mrt6 v8, v9, v10, v11 done
        0xBF810000,             // s_endpgm
    ]),
    ("mrt-float2", true, [
        0x7E0002FF, 0x3F800000, // v_mov_b32 v0, 1.0f
        0x7E0202FF, 0x3E800000, // v_mov_b32 v1, 0.25f
        0x7E0402FF, 0x3E800000, // v_mov_b32 v2, 0.25f
        0x7E0602FF, 0x3F000000, // v_mov_b32 v3, 0.5f
        0xF800000F, 0x03020100, // exp mrt0 v0, v1, v2, v3
        0xF800081F, 0x03020100, // exp mrt1 v0, v1, v2, v3 done
        0xBF810000,             // s_endpgm
    ]),
    ("mrt8", true, [
        0x7E0002FF, 0x3F800000, // v_mov_b32 v0, 1.0f
        0x7E0202FF, 0x00000000, // v_mov_b32 v1, 0.0f
        0x7E0402FF, 0x00000000, // v_mov_b32 v2, 0.0f
        0x7E0602FF, 0x3F800000, // v_mov_b32 v3, 1.0f
        0xF800000F, 0x03020100, // exp mrt0 v0, v1, v2, v3
        0xF800001F, 0x03020100, // exp mrt1 v0, v1, v2, v3
        0xF800002F, 0x03020100, // exp mrt2 v0, v1, v2, v3
        0xF800003F, 0x03020100, // exp mrt3 v0, v1, v2, v3
        0xF800004F, 0x03020100, // exp mrt4 v0, v1, v2, v3
        0xF800005F, 0x03020100, // exp mrt5 v0, v1, v2, v3
        0xF800006F, 0x03020100, // exp mrt6 v0, v1, v2, v3
        0xF800087F, 0x03020100, // exp mrt7 v0, v1, v2, v3 done
        0xBF810000,             // s_endpgm
    ]),
    ("mrt-partial", true, [
        0x7E0002FF, 0x3F4CCCCD, // v_mov_b32 v0, 0.8f
        0x7E0202FF, 0x3F333333, // v_mov_b32 v1, 0.7f
        0xF8000803, 0x03020100, // exp mrt0 v0, v1, off, off done
        0xBF810000,             // s_endpgm
    ]),
    ("mrt-partial-merge", true, [
        0x7E0002FF, 0x3DCCCCCD, // v_mov_b32 v0, 0.1f
        0x7E0202FF, 0x3E4CCCCD, // v_mov_b32 v1, 0.2f
        0x7E0C02FF, 0x3E99999A, // v_mov_b32 v6, 0.3f
        0x7E0E02FF, 0x3ECCCCCD, // v_mov_b32 v7, 0.4f
        0xF8000003, 0x03020100, // exp mrt0 v0, v1, off, off
        0xF800080C, 0x07060504, // exp mrt0 off, off, v6, v7 done
        0xBF810000,             // s_endpgm
    ]),
    ("sopp-hints", true, [
        0xBFA10001,             // s_clause 0x1
        0xBFA30000,             // s_waitcnt_depctr 0x0
        0xBF810000,             // s_endpgm
    ]),
    // s_round_mode / s_denorm_mode write the FP MODE state and must keep
    // failing decode loudly until their semantics are modeled (see #108);
    // this program pins that behavior.
    ("sopp-mode", false, [
        0xBFA40000,             // s_round_mode 0x0
        0xBFA50000,             // s_denorm_mode 0x0
        0xBF810000,             // s_endpgm
    ]),
    // Executable end-to-end test: compute with real ALU instructions, then
    // buffer_store_dword results to guestBuffers[0] at offsets 0/4/8, prove
    // that a store with EXEC=0 does not land (offset 12 stays sentinel), and
    // that stores work again after EXEC is restored (offset 16).
    ("exec", true, [
        0xBFA10001,             // s_clause 0x1 (hint no-op in an executed program, needs #108)
        0x7E0002FF, 0x3FC00000, // v_mov_b32 v0, 1.5f
        0x7E0202FF, 0x40100000, // v_mov_b32 v1, 2.25f
        0x7E0402FF, 0x41200000, // v_mov_b32 v2, 10.0f
        0x56040300,             // v_fmac_f32 v2, v0, v1      -> v2 = fma(1.5, 2.25, 10.0)
        0x7E0602FF, 0x7FFFFFFF, // v_mov_b32 v3, 0x7FFFFFFF
        0x7E0802FF, 0x00010003, // v_mov_b32 v4, 0x00010003
        0xD56C0005, 0x00020903, // v_mul_hi_i32 v5, v3, v4
        0xD56B0006, 0x00020903, // v_mul_lo_i32 v6, v3, v4
        0xE0700000, 0x80020200, // buffer_store_dword v2, off, s[8:11], 0
        0xE0700004, 0x80020500, // buffer_store_dword v5, off, s[8:11], 0 offset:4
        0xE0700008, 0x80020600, // buffer_store_dword v6, off, s[8:11], 0 offset:8
        0xBEFE0380,             // s_mov_b32 exec_lo, 0       -> lane inactive
        0xE070000C, 0x80020200, // buffer_store_dword v2, off, s[8:11], 0 offset:12 (masked, must not land)
        0xBEFE03C1,             // s_mov_b32 exec_lo, -1      -> lane active again
        0xE0700010, 0x80020000, // buffer_store_dword v0, off, s[8:11], 0 offset:16
        0xBF810000,             // s_endpgm
    ]),
];

var assembly = typeof(CxaGuardExports).Assembly;
var shaderTranslator = assembly.GetType("SharpEmu.Libs.Agc.Gen5ShaderTranslator")
    ?? throw new InvalidOperationException("Gen5ShaderTranslator not found");
var spirvTranslator = assembly.GetType("SharpEmu.Libs.Agc.Gen5SpirvTranslator")
    ?? throw new InvalidOperationException("Gen5SpirvTranslator not found");
var describe = shaderTranslator.GetMethod(
    "Describe",
    BindingFlags.Public | BindingFlags.Static)
    ?? throw new InvalidOperationException("Gen5ShaderTranslator.Describe not found");
var tryDecode = shaderTranslator.GetMethod(
    "TryDecodeProgram",
    BindingFlags.NonPublic | BindingFlags.Static)
    ?? throw new InvalidOperationException("Gen5ShaderTranslator.TryDecodeProgram not found");
var stateType = assembly.GetType("SharpEmu.Libs.Agc.Gen5ShaderState")
    ?? throw new InvalidOperationException("Gen5ShaderState not found");
var evaluationType = assembly.GetType("SharpEmu.Libs.Agc.Gen5ShaderEvaluation")
    ?? throw new InvalidOperationException("Gen5ShaderEvaluation not found");
var imageBindingType = assembly.GetType("SharpEmu.Libs.Agc.Gen5ImageBinding")
    ?? throw new InvalidOperationException("Gen5ImageBinding not found");
var globalBindingType = assembly.GetType("SharpEmu.Libs.Agc.Gen5GlobalMemoryBinding")
    ?? throw new InvalidOperationException("Gen5GlobalMemoryBinding not found");
var pixelOutputBindingType = assembly.GetType("SharpEmu.Libs.Agc.Gen5PixelOutputBinding")
    ?? throw new InvalidOperationException("Gen5PixelOutputBinding not found");
var pixelOutputKindType = assembly.GetType("SharpEmu.Libs.Agc.Gen5PixelOutputKind")
    ?? throw new InvalidOperationException("Gen5PixelOutputKind not found");
var tryCompile = spirvTranslator.GetMethod(
    "TryCompileVertexShader",
    BindingFlags.Public | BindingFlags.Static)
    ?? throw new InvalidOperationException("Gen5SpirvTranslator.TryCompileVertexShader not found");
var tryCompilePixel = spirvTranslator.GetMethods(BindingFlags.Public | BindingFlags.Static)
    .Single(method =>
        method.Name == "TryCompilePixelShader" &&
        method.GetParameters()[2].ParameterType.IsGenericType);
var tryCompileCompute = spirvTranslator.GetMethod(
    "TryCompileComputeShader",
    BindingFlags.Public | BindingFlags.Static)
    ?? throw new InvalidOperationException("Gen5SpirvTranslator.TryCompileComputeShader not found");

var outputDirectory = args.Length > 0
    ? args[0]
    : Path.Combine(AppContext.BaseDirectory, "spv");
Directory.CreateDirectory(outputDirectory);

var failures = 0;
foreach (var (name, expectTranslate, words) in testPrograms)
{
    var memory = new FakeMemory();
    memory.AddRegion(ProgramAddress, words);
    var ctx = new CpuContext(memory, Generation.Gen5);

    Console.WriteLine(
        $"[{name}] decode: " +
        (string)describe.Invoke(null, [ctx, ProgramAddress, ProgramAddress])!);

    object?[] decodeArgs = [ctx, ProgramAddress, null, null];
    if (!(bool)tryDecode.Invoke(null, decodeArgs)!)
    {
        if (expectTranslate)
        {
            failures++;
            Console.WriteLine($"[{name}] FAILED: decode error ({decodeArgs[3]})");
        }
        else
        {
            Console.WriteLine($"[{name}] decode failed as expected ({decodeArgs[3]})");
        }

        continue;
    }

    if (!expectTranslate)
    {
        failures++;
        Console.WriteLine(
            $"[{name}] FAILED: decoded successfully but is pinned as a decode failure — " +
            "if the new decode support is intentional, its semantics need verifying here first");
        continue;
    }

    // Buffer stores need a global-memory binding; the emitter resolves them by
    // instruction PC, so collect store PCs from the decoded program itself.
    var programObj = decodeArgs[2]!;
    var instructions = (System.Collections.IEnumerable)programObj
        .GetType().GetProperty("Instructions")!.GetValue(programObj)!;
    var storePcs = new List<uint>();
    foreach (var instruction in instructions)
    {
        var op = (string)instruction.GetType().GetProperty("Opcode")!.GetValue(instruction)!;
        if (op.StartsWith("BufferStore", StringComparison.Ordinal))
        {
            storePcs.Add((uint)instruction.GetType().GetProperty("Pc")!.GetValue(instruction)!);
        }
    }

    // The binding's scalar base (8 -> s[8:11]) must match the srsrc field of
    // the hand-assembled buffer_store words, and the 64-byte backing store
    // must cover every hand-assembled store offset.
    var globalBindings = Array.CreateInstance(globalBindingType, storePcs.Count > 0 ? 1 : 0);
    if (storePcs.Count > 0)
    {
        globalBindings.SetValue(
            Activator.CreateInstance(
                globalBindingType,
                8u,
                0UL,
                (IReadOnlyList<uint>)storePcs,
                new byte[64]),
            0);
    }

    var state = Activator.CreateInstance(
        stateType,
        programObj,
        new uint[16],
        null,
        null,
        0u)!;
    var evaluation = Activator.CreateInstance(
        evaluationType,
        new uint[256],
        new uint[256],
        new Dictionary<uint, IReadOnlyList<uint>>(),
        Array.CreateInstance(imageBindingType, 0),
        globalBindings,
        null,
        null,
        null)!;

    var compileArgs = PadWithDefaults(tryCompile, [state, evaluation, null, null]);
    if ((bool)tryCompile.Invoke(null, BindingFlags.OptionalParamBinding, null, compileArgs, null)!)
    {
        var shader = compileArgs[2]!;
        var spirv = (byte[])shader.GetType().GetProperty("Spirv")!.GetValue(shader)!;
        var path = Path.Combine(outputDirectory, $"{name}.spv");
        File.WriteAllBytes(path, spirv);
        Console.WriteLine($"[{name}] emit: success, {spirv.Length} bytes -> {path}");
    }
    else
    {
        failures++;
        Console.WriteLine($"[{name}] emit: FAILED ({compileArgs[3]})");
    }

    var computeArgs = PadWithDefaults(tryCompileCompute, [state, evaluation, 1u, 1u, 1u, null, null]);
    if ((bool)tryCompileCompute.Invoke(null, BindingFlags.OptionalParamBinding, null, computeArgs, null)!)
    {
        var shader = computeArgs[5]!;
        var spirv = (byte[])shader.GetType().GetProperty("Spirv")!.GetValue(shader)!;
        var path = Path.Combine(outputDirectory, $"{name}-cs.spv");
        File.WriteAllBytes(path, spirv);
        Console.WriteLine($"[{name}] compute emit: success, {spirv.Length} bytes -> {path}");
    }
    else
    {
        failures++;
        Console.WriteLine($"[{name}] compute emit: FAILED ({computeArgs[6]})");
    }

    if (name.StartsWith("mrt", StringComparison.Ordinal))
    {
        (uint GuestSlot, uint HostLocation, string Kind)[] outputSpecs = name switch
        {
            "mrt" => new (uint GuestSlot, uint HostLocation, string Kind)[]
            {
                (0, 0, "Float"),
                (3, 1, "Uint"),
                (6, 2, "Sint"),
            },
            "mrt-float2" => [(0, 0, "Float"), (1, 1, "Float")],
            "mrt8" => Enumerable.Range(0, 8)
                .Select(index => ((uint)index, (uint)index, "Float"))
                .ToArray(),
            _ => [(0, 0, "Float")],
        };
        var pixelOutputs = Array.CreateInstance(pixelOutputBindingType, outputSpecs.Length);
        for (var index = 0; index < outputSpecs.Length; index++)
        {
            var spec = outputSpecs[index];
            pixelOutputs.SetValue(
                Activator.CreateInstance(
                    pixelOutputBindingType,
                    spec.GuestSlot,
                    spec.HostLocation,
                    Enum.Parse(pixelOutputKindType, spec.Kind)),
                index);
        }

        var pixelArgs = PadWithDefaults(
            tryCompilePixel,
            [state, evaluation, pixelOutputs, null, null]);
        if ((bool)tryCompilePixel.Invoke(
                null,
                BindingFlags.OptionalParamBinding,
                null,
                pixelArgs,
                null)!)
        {
            var shader = pixelArgs[3]!;
            var spirv = (byte[])shader.GetType().GetProperty("Spirv")!.GetValue(shader)!;
            var path = Path.Combine(outputDirectory, $"{name}-ps.spv");
            File.WriteAllBytes(path, spirv);
            Console.WriteLine($"[{name}] pixel emit: success, {spirv.Length} bytes -> {path}");
        }
        else
        {
            failures++;
            Console.WriteLine($"[{name}] pixel emit: FAILED ({pixelArgs[4]})");
        }

        if (name == "mrt")
        {
            var invalidOutputs = Array.CreateInstance(pixelOutputBindingType, 2);
            invalidOutputs.SetValue(
                Activator.CreateInstance(
                    pixelOutputBindingType,
                    0u,
                    0u,
                    Enum.Parse(pixelOutputKindType, "Float")),
                0);
            invalidOutputs.SetValue(
                Activator.CreateInstance(
                    pixelOutputBindingType,
                    3u,
                    7u,
                    Enum.Parse(pixelOutputKindType, "Float")),
                1);
            var invalidPixelArgs = PadWithDefaults(
                tryCompilePixel,
                [state, evaluation, invalidOutputs, null, null]);
            if ((bool)tryCompilePixel.Invoke(
                    null,
                    BindingFlags.OptionalParamBinding,
                    null,
                    invalidPixelArgs,
                    null)!)
            {
                failures++;
                Console.WriteLine("[mrt] FAILED: sparse host locations were accepted");
            }
            else
            {
                Console.WriteLine($"[mrt] sparse host locations rejected as expected ({invalidPixelArgs[4]})");
            }
        }
    }
}

Console.WriteLine(failures == 0
    ? "RESULT: all programs behaved as expected"
    : $"RESULT: {failures} unexpected outcome(s)");
Environment.ExitCode = failures == 0 ? 0 : 1;

// Reflection Invoke does not apply C# default parameter values, so a newly
// added optional parameter on a translator entry point would otherwise throw
// TargetParameterCountException. Type.Missing + OptionalParamBinding lets the
// runtime substitute the declared defaults; only a new *required* parameter
// should force a tool update.
static object?[] PadWithDefaults(MethodInfo method, object?[] arguments)
{
    var parameters = method.GetParameters();
    if (arguments.Length > parameters.Length)
    {
        throw new InvalidOperationException(
            $"{method.DeclaringType?.Name}.{method.Name} takes fewer parameters than the tool supplies");
    }

    var padded = new object?[parameters.Length];
    arguments.CopyTo(padded, 0);
    for (var i = arguments.Length; i < padded.Length; i++)
    {
        if (!parameters[i].IsOptional)
        {
            throw new InvalidOperationException(
                $"{method.DeclaringType?.Name}.{method.Name} gained a required parameter " +
                $"'{parameters[i].Name}' — the tool needs updating");
        }

        padded[i] = Type.Missing;
    }

    return padded;
}

internal sealed class FakeMemory : ICpuMemory
{
    private readonly List<(ulong Base, byte[] Data)> _regions = [];

    public void AddRegion(ulong baseAddress, uint[] words)
    {
        var bytes = new byte[words.Length * sizeof(uint)];
        for (var index = 0; index < words.Length; index++)
        {
            BinaryPrimitives.WriteUInt32LittleEndian(
                bytes.AsSpan(index * sizeof(uint)),
                words[index]);
        }

        _regions.Add((baseAddress, bytes));
    }

    public bool TryRead(ulong virtualAddress, Span<byte> destination)
    {
        foreach (var (baseAddress, data) in _regions)
        {
            if (virtualAddress >= baseAddress &&
                virtualAddress + (ulong)destination.Length <= baseAddress + (ulong)data.Length)
            {
                data.AsSpan(
                    (int)(virtualAddress - baseAddress),
                    destination.Length).CopyTo(destination);
                return true;
            }
        }

        return false;
    }

    public bool TryWrite(ulong virtualAddress, ReadOnlySpan<byte> source) => false;
}