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#include "src/tint/lang/glsl/validate/validate.h"

#include <string>

#include "glslang/Public/ResourceLimits.h"
#include "glslang/Public/ShaderLang.h"
#include "src/tint/utils/macros/static_init.h"
#include "src/tint/utils/text/string_stream.h"

namespace tint::glsl::validate {

namespace {

EShLanguage PipelineStageToEshLanguage(tint::ast::PipelineStage stage) {
    switch (stage) {
        case tint::ast::PipelineStage::kFragment:
            return EShLangFragment;
        case tint::ast::PipelineStage::kVertex:
            return EShLangVertex;
        case tint::ast::PipelineStage::kCompute:
            return EShLangCompute;
        default:
            TINT_UNREACHABLE();
            // MSVC considered the inlined call:
            // `lang = PipelineStageToEshLanguage()` as potentially uninitialized
            TINT_MSVC_ONLY(return EShLangCompute;)
    }
}

}  // namespace

Result<SuccessType> Validate(const std::string& source, tint::ast::PipelineStage stage) {
    TINT_STATIC_INIT(glslang::InitializeProcess());

    const char* strings[1] = {source.c_str()};
    int lengths[1] = {static_cast<int>(source.length())};

    EShLanguage lang = PipelineStageToEshLanguage(stage);
    glslang::TShader shader(lang);
    shader.setStringsWithLengths(strings, lengths, 1);
    shader.setEntryPoint("main");

    bool result = shader.parse(GetDefaultResources(), 310, EEsProfile, false, false, EShMsgDefault);

    if (!result) {
        StringStream err;
        err << "Error parsing GLSL shader:\n"
            << shader.getInfoLog() << "\n"
            << shader.getInfoDebugLog() << "\n";
        return Failure{err.str()};
    }

    return Success;
}

}  // namespace tint::glsl::validate