// Copyright 2017-2018 ccls Authors
// SPDX-License-Identifier: Apache-2.0

#include "clang_tu.hh"

#include "config.h"
#include "platform.h"

#include <clang/AST/Type.h>
#include <clang/Lex/Lexer.h>
#include <llvm/Support/Path.h>

using namespace clang;

std::string PathFromFileEntry(const FileEntry &file) {
  StringRef Name = file.tryGetRealPathName();
  if (Name.empty())
    Name = file.getName();
  std::string ret = NormalizePath(Name);
  // Resolve /usr/include/c++/7.3.0 symlink.
  if (!llvm::any_of(g_config->workspaceFolders, [&](const std::string &root) {
        return StartsWith(ret, root);
      })) {
    SmallString<256> dest;
    llvm::sys::fs::real_path(ret, dest);
    ret = llvm::sys::path::convert_to_slash(dest.str());
  }
  return ret;
}

static Position Decomposed2LineAndCol(const SourceManager &SM,
                               std::pair<FileID, unsigned> I) {
  int l = (int)SM.getLineNumber(I.first, I.second) - 1,
      c = (int)SM.getColumnNumber(I.first, I.second) - 1;
  return {(int16_t)std::min<int>(l, INT16_MAX),
          (int16_t)std::min<int>(c, INT16_MAX)};
}

Range FromCharSourceRange(const SourceManager &SM, const LangOptions &LangOpts,
                          CharSourceRange R,
                          llvm::sys::fs::UniqueID *UniqueID) {
  SourceLocation BLoc = R.getBegin(), ELoc = R.getEnd();
  std::pair<FileID, unsigned> BInfo = SM.getDecomposedLoc(BLoc),
                              EInfo = SM.getDecomposedLoc(ELoc);
  if (R.isTokenRange())
    EInfo.second += Lexer::MeasureTokenLength(ELoc, SM, LangOpts);
  if (UniqueID) {
    if (const FileEntry *F = SM.getFileEntryForID(BInfo.first))
      *UniqueID = F->getUniqueID();
    else
      *UniqueID = llvm::sys::fs::UniqueID(0, 0);
  }
  return {Decomposed2LineAndCol(SM, BInfo), Decomposed2LineAndCol(SM, EInfo)};
}

Range FromCharRange(const SourceManager &SM, const LangOptions &Lang,
                    SourceRange R, llvm::sys::fs::UniqueID *UniqueID) {
  return FromCharSourceRange(SM, Lang, CharSourceRange::getCharRange(R),
                             UniqueID);
}

Range FromTokenRange(const SourceManager &SM, const LangOptions &Lang,
                     SourceRange R, llvm::sys::fs::UniqueID *UniqueID) {
  return FromCharSourceRange(SM, Lang, CharSourceRange::getTokenRange(R),
                             UniqueID);
}

Range FromTokenRangeDefaulted(const SourceManager &SM, const LangOptions &Lang,
                              SourceRange R, const FileEntry *FE, Range range) {
  auto I = SM.getDecomposedLoc(SM.getExpansionLoc(R.getBegin()));
  if (SM.getFileEntryForID(I.first) == FE)
    range.start = Decomposed2LineAndCol(SM, I);
  SourceLocation L = SM.getExpansionLoc(R.getEnd());
  I = SM.getDecomposedLoc(L);
  if (SM.getFileEntryForID(I.first) == FE) {
    I.second += Lexer::MeasureTokenLength(L, SM, Lang);
    range.end = Decomposed2LineAndCol(SM, I);
  }
  return range;
}

std::unique_ptr<CompilerInvocation>
BuildCompilerInvocation(std::vector<const char *> args,
                        IntrusiveRefCntPtr<llvm::vfs::FileSystem> VFS) {
  std::string save = "-resource-dir=" + g_config->clang.resourceDir;
  args.push_back(save.c_str());
  IntrusiveRefCntPtr<DiagnosticsEngine> Diags(
      CompilerInstance::createDiagnostics(new DiagnosticOptions));
  std::unique_ptr<CompilerInvocation> CI =
      createInvocationFromCommandLine(args, Diags, VFS);
  if (CI) {
    CI->getDiagnosticOpts().IgnoreWarnings = true;
    CI->getFrontendOpts().DisableFree = false;
    CI->getLangOpts()->SpellChecking = false;
  }
  return CI;
}

// clang::BuiltinType::getName without PrintingPolicy
const char *ClangBuiltinTypeName(int kind) {
  switch (BuiltinType::Kind(kind)) {
  case BuiltinType::Void:
    return "void";
  case BuiltinType::Bool:
    return "bool";
  case BuiltinType::Char_S:
  case BuiltinType::Char_U:
    return "char";
  case BuiltinType::SChar:
    return "signed char";
  case BuiltinType::Short:
    return "short";
  case BuiltinType::Int:
    return "int";
  case BuiltinType::Long:
    return "long";
  case BuiltinType::LongLong:
    return "long long";
  case BuiltinType::Int128:
    return "__int128";
  case BuiltinType::UChar:
    return "unsigned char";
  case BuiltinType::UShort:
    return "unsigned short";
  case BuiltinType::UInt:
    return "unsigned int";
  case BuiltinType::ULong:
    return "unsigned long";
  case BuiltinType::ULongLong:
    return "unsigned long long";
  case BuiltinType::UInt128:
    return "unsigned __int128";
  case BuiltinType::Half:
    return "__fp16";
  case BuiltinType::Float:
    return "float";
  case BuiltinType::Double:
    return "double";
  case BuiltinType::LongDouble:
    return "long double";
#if LLVM_VERSION_MAJOR >= 7
  case BuiltinType::ShortAccum:
    return "short _Accum";
  case BuiltinType::Accum:
    return "_Accum";
  case BuiltinType::LongAccum:
    return "long _Accum";
  case BuiltinType::UShortAccum:
    return "unsigned short _Accum";
  case BuiltinType::UAccum:
    return "unsigned _Accum";
  case BuiltinType::ULongAccum:
    return "unsigned long _Accum";
  case BuiltinType::BuiltinType::ShortFract:
    return "short _Fract";
  case BuiltinType::BuiltinType::Fract:
    return "_Fract";
  case BuiltinType::BuiltinType::LongFract:
    return "long _Fract";
  case BuiltinType::BuiltinType::UShortFract:
    return "unsigned short _Fract";
  case BuiltinType::BuiltinType::UFract:
    return "unsigned _Fract";
  case BuiltinType::BuiltinType::ULongFract:
    return "unsigned long _Fract";
  case BuiltinType::BuiltinType::SatShortAccum:
    return "_Sat short _Accum";
  case BuiltinType::BuiltinType::SatAccum:
    return "_Sat _Accum";
  case BuiltinType::BuiltinType::SatLongAccum:
    return "_Sat long _Accum";
  case BuiltinType::BuiltinType::SatUShortAccum:
    return "_Sat unsigned short _Accum";
  case BuiltinType::BuiltinType::SatUAccum:
    return "_Sat unsigned _Accum";
  case BuiltinType::BuiltinType::SatULongAccum:
    return "_Sat unsigned long _Accum";
  case BuiltinType::BuiltinType::SatShortFract:
    return "_Sat short _Fract";
  case BuiltinType::BuiltinType::SatFract:
    return "_Sat _Fract";
  case BuiltinType::BuiltinType::SatLongFract:
    return "_Sat long _Fract";
  case BuiltinType::BuiltinType::SatUShortFract:
    return "_Sat unsigned short _Fract";
  case BuiltinType::BuiltinType::SatUFract:
    return "_Sat unsigned _Fract";
  case BuiltinType::BuiltinType::SatULongFract:
    return "_Sat unsigned long _Fract";
#endif
  case BuiltinType::Float16:
    return "_Float16";
  case BuiltinType::Float128:
    return "__float128";
  case BuiltinType::WChar_S:
  case BuiltinType::WChar_U:
    return "wchar_t";
#if LLVM_VERSION_MAJOR >= 7
  case BuiltinType::Char8:
    return "char8_t";
#endif
  case BuiltinType::Char16:
    return "char16_t";
  case BuiltinType::Char32:
    return "char32_t";
  case BuiltinType::NullPtr:
    return "nullptr_t";
  case BuiltinType::Overload:
    return "<overloaded function type>";
  case BuiltinType::BoundMember:
    return "<bound member function type>";
  case BuiltinType::PseudoObject:
    return "<pseudo-object type>";
  case BuiltinType::Dependent:
    return "<dependent type>";
  case BuiltinType::UnknownAny:
    return "<unknown type>";
  case BuiltinType::ARCUnbridgedCast:
    return "<ARC unbridged cast type>";
  case BuiltinType::BuiltinFn:
    return "<builtin fn type>";
  case BuiltinType::ObjCId:
    return "id";
  case BuiltinType::ObjCClass:
    return "Class";
  case BuiltinType::ObjCSel:
    return "SEL";
  case BuiltinType::OCLSampler:
    return "sampler_t";
  case BuiltinType::OCLEvent:
    return "event_t";
  case BuiltinType::OCLClkEvent:
    return "clk_event_t";
  case BuiltinType::OCLQueue:
    return "queue_t";
  case BuiltinType::OCLReserveID:
    return "reserve_id_t";
  case BuiltinType::OMPArraySection:
    return "<OpenMP array section type>";
  default:
    return "";
  }
}