//===- Multilib.cpp - Multilib Implementation -----------------------------===//
//
// 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 "clang/Driver/Multilib.h"
#include "clang/Basic/LLVM.h"
#include "llvm/ADT/SmallString.h"
#include "llvm/ADT/StringMap.h"
#include "llvm/ADT/StringRef.h"
#include "llvm/ADT/StringSet.h"
#include "llvm/Support/Compiler.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/Path.h"
#include "llvm/Support/Regex.h"
#include "llvm/Support/raw_ostream.h"
#include <algorithm>
#include <cassert>
#include <string>

using namespace clang;
using namespace driver;
using namespace llvm::sys;

Multilib::Multilib(StringRef GCCSuffix, StringRef OSSuffix,
                   StringRef IncludeSuffix, const flags_list &Flags)
    : GCCSuffix(GCCSuffix), OSSuffix(OSSuffix), IncludeSuffix(IncludeSuffix),
      Flags(Flags) {
  assert(GCCSuffix.empty() ||
         (StringRef(GCCSuffix).front() == '/' && GCCSuffix.size() > 1));
  assert(OSSuffix.empty() ||
         (StringRef(OSSuffix).front() == '/' && OSSuffix.size() > 1));
  assert(IncludeSuffix.empty() ||
         (StringRef(IncludeSuffix).front() == '/' && IncludeSuffix.size() > 1));
}

LLVM_DUMP_METHOD void Multilib::dump() const {
  print(llvm::errs());
}

void Multilib::print(raw_ostream &OS) const {
  if (GCCSuffix.empty())
    OS << ".";
  else {
    OS << StringRef(GCCSuffix).drop_front();
  }
  OS << ";";
  for (StringRef Flag : Flags) {
    if (Flag.front() == '+')
      OS << "@" << Flag.substr(1);
  }
}

bool Multilib::operator==(const Multilib &Other) const {
  // Check whether the flags sets match
  // allowing for the match to be order invariant
  llvm::StringSet<> MyFlags;
  for (const auto &Flag : Flags)
    MyFlags.insert(Flag);

  for (const auto &Flag : Other.Flags)
    if (!MyFlags.contains(Flag))
      return false;

  if (osSuffix() != Other.osSuffix())
    return false;

  if (gccSuffix() != Other.gccSuffix())
    return false;

  if (includeSuffix() != Other.includeSuffix())
    return false;

  return true;
}

raw_ostream &clang::driver::operator<<(raw_ostream &OS, const Multilib &M) {
  M.print(OS);
  return OS;
}

MultilibSet &MultilibSet::FilterOut(FilterCallback F) {
  llvm::erase_if(Multilibs, F);
  return *this;
}

void MultilibSet::push_back(const Multilib &M) { Multilibs.push_back(M); }

MultilibSet::multilib_list
MultilibSet::select(const Multilib::flags_list &Flags) const {
  llvm::StringSet<> FlagSet;
  for (const auto &Flag : Flags)
    FlagSet.insert(Flag);

  multilib_list Result;
  llvm::copy_if(Multilibs, std::back_inserter(Result),
                [&FlagSet](const Multilib &M) {
                  for (const std::string &F : M.flags())
                    if (!FlagSet.contains(F))
                      return false;
                  return true;
                });
  return Result;
}

bool MultilibSet::select(const Multilib::flags_list &Flags,
                         Multilib &Selected) const {
  multilib_list Result = select(Flags);
  if (Result.empty())
    return false;
  Selected = Result.back();
  return true;
}

LLVM_DUMP_METHOD void MultilibSet::dump() const {
  print(llvm::errs());
}

void MultilibSet::print(raw_ostream &OS) const {
  for (const auto &M : *this)
    OS << M << "\n";
}

raw_ostream &clang::driver::operator<<(raw_ostream &OS, const MultilibSet &MS) {
  MS.print(OS);
  return OS;
}