//===--- FrontendOptions.cpp ----------------------------------------------===//
//
// This source file is part of the Swift.org open source project
//
// Copyright (c) 2014 - 2017 Apple Inc. and the Swift project authors
// Licensed under Apache License v2.0 with Runtime Library Exception
//
// See https://swift.org/LICENSE.txt for license information
// See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
//
//===----------------------------------------------------------------------===//

#include "swift/Frontend/FrontendOptions.h"

#include "swift/AST/DiagnosticsFrontend.h"
#include "swift/Option/Options.h"
#include "swift/Parse/Lexer.h"
#include "swift/Strings.h"
#include "llvm/Option/Arg.h"
#include "llvm/Option/ArgList.h"
#include "llvm/Option/Option.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/FileSystem.h"
#include "llvm/Support/LineIterator.h"
#include "llvm/Support/Path.h"

using namespace swift;
using namespace llvm::opt;

bool FrontendInputs::shouldTreatAsLLVM() const {
  if (hasUniqueInputFilename()) {
    StringRef Input(getFilenameOfFirstInput());
    return llvm::sys::path::extension(Input).endswith(LLVM_BC_EXTENSION) ||
           llvm::sys::path::extension(Input).endswith(LLVM_IR_EXTENSION);
  }
  return false;
}

bool FrontendInputs::shouldTreatAsSIL() const {
  if (hasUniqueInputFilename()) {
    // If we have exactly one input filename, and its extension is "sil",
    // treat the input as SIL.
    StringRef Input(getFilenameOfFirstInput());
    return llvm::sys::path::extension(Input).endswith(SIL_EXTENSION);
  }
  // If we have one primary input and it's a filename with extension "sil",
  // treat the input as SIL.
  if (const Optional<StringRef> filename =
          getOptionalUniquePrimaryInputFilename()) {
    return llvm::sys::path::extension(filename.getValue())
        .endswith(SIL_EXTENSION);
  }
  return false;
}

bool FrontendInputs::verifyInputs(DiagnosticEngine &diags, bool treatAsSIL,
                                  bool isREPLRequested,
                                  bool isNoneRequested) const {
  if (isREPLRequested) {
    if (hasInputFilenames()) {
      diags.diagnose(SourceLoc(), diag::error_repl_requires_no_input_files);
      return true;
    }
  } else if (treatAsSIL && hasPrimaryInputs()) {
    // If we have the SIL as our primary input, we can waive the one file
    // requirement as long as all the other inputs are SIBs.
    for (unsigned i = 0, e = inputFilenameCount(); i != e; ++i) {
      if (i == getOptionalUniquePrimaryInput()->Index)
        continue;

      StringRef file(getInputFilenames()[i]);
      if (!llvm::sys::path::extension(file).endswith(SIB_EXTENSION)) {
        diags.diagnose(SourceLoc(),
                       diag::error_mode_requires_one_sil_multi_sib);
        return true;
      }
    }
  } else if (treatAsSIL) {
    if (!hasUniqueInputFilename()) {
      diags.diagnose(SourceLoc(), diag::error_mode_requires_one_input_file);
      return true;
    }
  } else if (!isNoneRequested) {
    if (!hasInputFilenames()) {
      diags.diagnose(SourceLoc(), diag::error_mode_requires_an_input_file);
      return true;
    }
  }
  return false;
}

void FrontendInputs::transformInputFilenames(
    const llvm::function_ref<std::string(std::string)> &fn) {
  for (auto &InputFile : InputFilenames) {
    InputFile = fn(InputFile);
  }
}

bool FrontendOptions::actionHasOutput() const {
  switch (RequestedAction) {
  case ActionType::NoneAction:
  case ActionType::Parse:
  case ActionType::Typecheck:
  case ActionType::DumpParse:
  case ActionType::DumpAST:
  case ActionType::EmitSyntax:
  case ActionType::DumpInterfaceHash:
  case ActionType::PrintAST:
  case ActionType::DumpScopeMaps:
  case ActionType::DumpTypeRefinementContexts:
    return false;
  case ActionType::EmitPCH:
  case ActionType::EmitSILGen:
  case ActionType::EmitSIL:
  case ActionType::EmitSIBGen:
  case ActionType::EmitSIB:
  case ActionType::EmitModuleOnly:
  case ActionType::MergeModules:
    return true;
  case ActionType::Immediate:
  case ActionType::REPL:
    return false;
  case ActionType::EmitAssembly:
  case ActionType::EmitIR:
  case ActionType::EmitBC:
  case ActionType::EmitObject:
  case ActionType::EmitImportedModules:
    return true;
  }
  llvm_unreachable("Unknown ActionType");
}

bool FrontendOptions::actionIsImmediate() const {
  switch (RequestedAction) {
  case ActionType::NoneAction:
  case ActionType::Parse:
  case ActionType::Typecheck:
  case ActionType::DumpParse:
  case ActionType::DumpAST:
  case ActionType::EmitSyntax:
  case ActionType::DumpInterfaceHash:
  case ActionType::PrintAST:
  case ActionType::DumpScopeMaps:
  case ActionType::DumpTypeRefinementContexts:
  case ActionType::EmitPCH:
  case ActionType::EmitSILGen:
  case ActionType::EmitSIL:
  case ActionType::EmitSIBGen:
  case ActionType::EmitSIB:
  case ActionType::EmitModuleOnly:
  case ActionType::MergeModules:
    return false;
  case ActionType::Immediate:
  case ActionType::REPL:
    return true;
  case ActionType::EmitAssembly:
  case ActionType::EmitIR:
  case ActionType::EmitBC:
  case ActionType::EmitObject:
  case ActionType::EmitImportedModules:
    return false;
  }
  llvm_unreachable("Unknown ActionType");
}

void FrontendOptions::forAllOutputPaths(
    std::function<void(const std::string &)> fn) const {
  if (RequestedAction != FrontendOptions::ActionType::EmitModuleOnly &&
      RequestedAction != FrontendOptions::ActionType::MergeModules) {
    for (const std::string &OutputFileName : OutputFilenames) {
      fn(OutputFileName);
    }
  }
  const std::string *outputs[] = {
    &ModuleOutputPath,
    &ModuleDocOutputPath,
    &ObjCHeaderOutputPath
  };
  for (const std::string *next : outputs) {
    if (!next->empty())
      fn(*next);
  }
}


StringRef FrontendOptions::originalPath() const {
  if (hasNamedOutputFile())
    // Put the serialized diagnostics file next to the output file.
    return getSingleOutputFilename();

  StringRef fn = Inputs.primaryInputFilenameIfAny();
  // If we have a primary input, so use that as the basis for the name of the
  // serialized diagnostics file, otherwise fall back on the
  // module name.
  return !fn.empty() ? llvm::sys::path::filename(fn) : StringRef(ModuleName);
}

bool FrontendOptions::isOutputFileDirectory() const {
  return hasNamedOutputFile() &&
         llvm::sys::fs::is_directory(getSingleOutputFilename());
}

const char *
FrontendOptions::suffixForPrincipalOutputFileForAction(ActionType action) {
  switch (action) {
  case ActionType::NoneAction:
    return nullptr;

  case ActionType::Parse:
  case ActionType::Typecheck:
  case ActionType::DumpParse:
  case ActionType::DumpInterfaceHash:
  case ActionType::DumpAST:
  case ActionType::EmitSyntax:
  case ActionType::PrintAST:
  case ActionType::DumpScopeMaps:
  case ActionType::DumpTypeRefinementContexts:
    return nullptr;

  case ActionType::EmitPCH:
    return PCH_EXTENSION;

  case ActionType::EmitSILGen:
  case ActionType::EmitSIL:
    return SIL_EXTENSION;

  case ActionType::EmitSIBGen:
  case ActionType::EmitSIB:
    return SIB_EXTENSION;

  case ActionType::MergeModules:
  case ActionType::EmitModuleOnly:
    return SERIALIZED_MODULE_EXTENSION;

  case ActionType::Immediate:
  case ActionType::REPL:
    // These modes have no frontend-generated output.
    return nullptr;

  case ActionType::EmitAssembly:
    return "s";

  case ActionType::EmitIR:
    return "ll";

  case ActionType::EmitBC:
    return "bc";

  case ActionType::EmitObject:
    return "o";

  case ActionType::EmitImportedModules:
    return "importedmodules";
  }
}

bool FrontendOptions::hasUnusedDependenciesFilePath() const {
  return !DependenciesFilePath.empty() &&
         !canActionEmitDependencies(RequestedAction);
}

bool FrontendOptions::canActionEmitDependencies(ActionType action) {
  switch (action) {
  case ActionType::NoneAction:
  case ActionType::DumpParse:
  case ActionType::DumpInterfaceHash:
  case ActionType::DumpAST:
  case ActionType::EmitSyntax:
  case ActionType::PrintAST:
  case ActionType::DumpScopeMaps:
  case ActionType::DumpTypeRefinementContexts:
  case ActionType::Immediate:
  case ActionType::REPL:
    return false;
  case ActionType::Parse:
  case ActionType::Typecheck:
  case ActionType::MergeModules:
  case ActionType::EmitModuleOnly:
  case ActionType::EmitPCH:
  case ActionType::EmitSILGen:
  case ActionType::EmitSIL:
  case ActionType::EmitSIBGen:
  case ActionType::EmitSIB:
  case ActionType::EmitIR:
  case ActionType::EmitBC:
  case ActionType::EmitAssembly:
  case ActionType::EmitObject:
  case ActionType::EmitImportedModules:
    return true;
  }
}

bool FrontendOptions::hasUnusedObjCHeaderOutputPath() const {
  return !ObjCHeaderOutputPath.empty() && !canActionEmitHeader(RequestedAction);
}

bool FrontendOptions::canActionEmitHeader(ActionType action) {
  switch (action) {
  case ActionType::NoneAction:
  case ActionType::DumpParse:
  case ActionType::DumpInterfaceHash:
  case ActionType::DumpAST:
  case ActionType::EmitSyntax:
  case ActionType::PrintAST:
  case ActionType::EmitPCH:
  case ActionType::DumpScopeMaps:
  case ActionType::DumpTypeRefinementContexts:
  case ActionType::Immediate:
  case ActionType::REPL:
    return false;
  case ActionType::Parse:
  case ActionType::Typecheck:
  case ActionType::MergeModules:
  case ActionType::EmitModuleOnly:
  case ActionType::EmitSILGen:
  case ActionType::EmitSIL:
  case ActionType::EmitSIBGen:
  case ActionType::EmitSIB:
  case ActionType::EmitIR:
  case ActionType::EmitBC:
  case ActionType::EmitAssembly:
  case ActionType::EmitObject:
  case ActionType::EmitImportedModules:
    return true;
  }
}

bool FrontendOptions::hasUnusedLoadedModuleTracePath() const {
  return !LoadedModuleTracePath.empty() &&
         !canActionEmitLoadedModuleTrace(RequestedAction);
}

bool FrontendOptions::canActionEmitLoadedModuleTrace(ActionType action) {
  switch (action) {
  case ActionType::NoneAction:
  case ActionType::Parse:
  case ActionType::DumpParse:
  case ActionType::DumpInterfaceHash:
  case ActionType::DumpAST:
  case ActionType::EmitSyntax:
  case ActionType::PrintAST:
  case ActionType::DumpScopeMaps:
  case ActionType::DumpTypeRefinementContexts:
  case ActionType::Immediate:
  case ActionType::REPL:
    return false;
  case ActionType::Typecheck:
  case ActionType::MergeModules:
  case ActionType::EmitModuleOnly:
  case ActionType::EmitPCH:
  case ActionType::EmitSILGen:
  case ActionType::EmitSIL:
  case ActionType::EmitSIBGen:
  case ActionType::EmitSIB:
  case ActionType::EmitIR:
  case ActionType::EmitBC:
  case ActionType::EmitAssembly:
  case ActionType::EmitObject:
  case ActionType::EmitImportedModules:
    return true;
  }
}

bool FrontendOptions::hasUnusedModuleOutputPath() const {
  return !ModuleOutputPath.empty() && !canActionEmitModule(RequestedAction);
}

bool FrontendOptions::hasUnusedModuleDocOutputPath() const {
  return !ModuleDocOutputPath.empty() && !canActionEmitModule(RequestedAction);
}

bool FrontendOptions::canActionEmitModule(ActionType action) {
  switch (action) {
  case ActionType::NoneAction:
  case ActionType::Parse:
  case ActionType::Typecheck:
  case ActionType::DumpParse:
  case ActionType::DumpInterfaceHash:
  case ActionType::DumpAST:
  case ActionType::EmitSyntax:
  case ActionType::PrintAST:
  case ActionType::EmitPCH:
  case ActionType::DumpScopeMaps:
  case ActionType::DumpTypeRefinementContexts:
  case ActionType::EmitSILGen:
  case ActionType::Immediate:
  case ActionType::REPL:
    return false;
  case ActionType::MergeModules:
  case ActionType::EmitModuleOnly:
  case ActionType::EmitSIL:
  case ActionType::EmitSIBGen:
  case ActionType::EmitSIB:
  case ActionType::EmitIR:
  case ActionType::EmitBC:
  case ActionType::EmitAssembly:
  case ActionType::EmitObject:
  case ActionType::EmitImportedModules:
    return true;
  }
}

bool FrontendOptions::canActionEmitModuleDoc(ActionType action) {
  return canActionEmitModule(action);
}

bool FrontendOptions::doesActionProduceOutput(ActionType action) {
  switch (action) {
    // FIXME: Some of these don't actually produce output
    // but for now stay consistent with the status quo.
  case ActionType::NoneAction:
  case ActionType::EmitPCH:
  case ActionType::EmitSIBGen:
  case ActionType::EmitSIB:
  case ActionType::MergeModules:
  case ActionType::EmitModuleOnly:
  case ActionType::EmitBC:
  case ActionType::EmitObject:
  case ActionType::Parse:
  case ActionType::Typecheck:
  case ActionType::DumpParse:
  case ActionType::DumpInterfaceHash:
  case ActionType::DumpAST:
  case ActionType::EmitSyntax:
  case ActionType::PrintAST:
  case ActionType::DumpScopeMaps:
  case ActionType::DumpTypeRefinementContexts:
  case ActionType::EmitImportedModules:
  case ActionType::EmitSILGen:
  case ActionType::EmitSIL:
  case ActionType::EmitAssembly:
  case ActionType::EmitIR:
    return true;

  case ActionType::Immediate:
  case ActionType::REPL:
    // These modes have no frontend-generated output.
    return false;
  }
}

bool FrontendOptions::doesActionProduceTextualOutput(ActionType action) {
  switch (action) {
  case ActionType::NoneAction:
  case ActionType::EmitPCH:
  case ActionType::EmitSIBGen:
  case ActionType::EmitSIB:
  case ActionType::MergeModules:
  case ActionType::EmitModuleOnly:
  case ActionType::EmitBC:
  case ActionType::EmitObject:
  case ActionType::Immediate:
  case ActionType::REPL:
    return false;

  case ActionType::Parse:
  case ActionType::Typecheck:
  case ActionType::DumpParse:
  case ActionType::DumpInterfaceHash:
  case ActionType::DumpAST:
  case ActionType::EmitSyntax:
  case ActionType::PrintAST:
  case ActionType::DumpScopeMaps:
  case ActionType::DumpTypeRefinementContexts:
  case ActionType::EmitImportedModules:
  case ActionType::EmitSILGen:
  case ActionType::EmitSIL:
  case ActionType::EmitAssembly:
  case ActionType::EmitIR:
    return true;
  }
}