//===-- ClangPersistentVariables.cpp --------------------------------------===//

//

// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.

// See https://llvm.org/LICENSE.txt for license information.

// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception

//

//===----------------------------------------------------------------------===//

#include "ClangPersistentVariables.h"

#include "ClangASTImporter.h"

#include "ClangModulesDeclVendor.h"

#include "Plugins/TypeSystem/Clang/TypeSystemClang.h"

#include "lldb/Core/Value.h"

#include "lldb/Target/Target.h"

#include "lldb/Utility/DataExtractor.h"

#include "lldb/Utility/Log.h"

#include "lldb/Utility/StreamString.h"

#include "clang/AST/Decl.h"

#include "llvm/ADT/StringMap.h"

#include <optional>

#include <memory>

using namespace lldb;

using namespace lldb_private;

char ClangPersistentVariables::ID;

ClangPersistentVariables::ClangPersistentVariables(

    std::shared_ptr<Target> target_sp)

    : m_target_sp(target_sp) {}

ExpressionVariableSP ClangPersistentVariables::CreatePersistentVariable(

    const lldb::ValueObjectSP &valobj_sp) {

  return AddNewlyConstructedVariable(new ClangExpressionVariable(valobj_sp));

}

ExpressionVariableSP ClangPersistentVariables::CreatePersistentVariable(

    ExecutionContextScope *exe_scope, ConstString name,

    const CompilerType &compiler_type, lldb::ByteOrder byte_order,

    uint32_t addr_byte_size) {

  return AddNewlyConstructedVariable(new ClangExpressionVariable(

      exe_scope, name, compiler_type, byte_order, addr_byte_size));

}

void ClangPersistentVariables::RemovePersistentVariable(

    lldb::ExpressionVariableSP variable) {

  RemoveVariable(variable);

  // Check if the removed variable was the last one that was created. If yes,

  // reuse the variable id for the next variable.

  // Nothing to do if we have not assigned a variable id so far.

  if (m_next_persistent_variable_id == 0)

    return;

  llvm::StringRef name = variable->GetName().GetStringRef();

  // Remove the prefix from the variable that only the indes is left.

  if (!name.consume_front(GetPersistentVariablePrefix(false)))

    return;

  // Check if the variable contained a variable id.

  uint32_t variable_id;

  if (name.getAsInteger(10, variable_id))

    return;

  // If it's the most recent variable id that was assigned, make sure that this

  // variable id will be used for the next persistent variable.

  if (variable_id == m_next_persistent_variable_id - 1)

    m_next_persistent_variable_id--;

}

std::optional<CompilerType>

ClangPersistentVariables::GetCompilerTypeFromPersistentDecl(

    ConstString type_name) {

  PersistentDecl p = m_persistent_decls.lookup(type_name.GetCString());

  if (p.m_decl == nullptr)

    return std::nullopt;

  if (clang::TypeDecl *tdecl = llvm::dyn_cast<clang::TypeDecl>(p.m_decl)) {

    opaque_compiler_type_t t = static_cast<opaque_compiler_type_t>(

        const_cast<clang::Type *>(tdecl->getTypeForDecl()));

    return CompilerType(p.m_context, t);

  }

  return std::nullopt;

}

void ClangPersistentVariables::RegisterPersistentDecl(

    ConstString name, clang::NamedDecl *decl,

    std::shared_ptr<TypeSystemClang> ctx) {

  PersistentDecl p = {decl, ctx};

  m_persistent_decls.insert(std::make_pair(name.GetCString(), p));

  if (clang::EnumDecl *enum_decl = llvm::dyn_cast<clang::EnumDecl>(decl)) {

    for (clang::EnumConstantDecl *enumerator_decl : enum_decl->enumerators()) {

      p = {enumerator_decl, ctx};

      m_persistent_decls.insert(std::make_pair(

          ConstString(enumerator_decl->getNameAsString()).GetCString(), p));

    }

  }

}

clang::NamedDecl *

ClangPersistentVariables::GetPersistentDecl(ConstString name) {

  return m_persistent_decls.lookup(name.GetCString()).m_decl;

}

std::shared_ptr<ClangASTImporter>

ClangPersistentVariables::GetClangASTImporter() {

  if (!m_ast_importer_sp) {

    m_ast_importer_sp = std::make_shared<ClangASTImporter>();

  }

  return m_ast_importer_sp;

}

std::shared_ptr<ClangModulesDeclVendor>

ClangPersistentVariables::GetClangModulesDeclVendor() {

  if (!m_modules_decl_vendor_sp) {

    m_modules_decl_vendor_sp.reset(

        ClangModulesDeclVendor::Create(*m_target_sp));

  }

  return m_modules_decl_vendor_sp;

}

ConstString

ClangPersistentVariables::GetNextPersistentVariableName(bool is_error) {

  llvm::SmallString<64> name;

  {

    llvm::raw_svector_ostream os(name);

    os << GetPersistentVariablePrefix(is_error)

       << m_next_persistent_variable_id++;

  }

  return ConstString(name);

}