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

#ifndef LLVM_CLANG_DEPENDENCYSCANNING_DEPENDENCYSCANNERIMPL_H
#define LLVM_CLANG_DEPENDENCYSCANNING_DEPENDENCYSCANNERIMPL_H

#include "clang/DependencyScanning/DependencyScanningFilesystem.h"
#include "clang/DependencyScanning/ModuleDepCollector.h"
#include "clang/Driver/Compilation.h"
#include "clang/Driver/Driver.h"
#include "clang/Frontend/CompilerInstance.h"
#include "clang/Frontend/CompilerInvocation.h"
#include "clang/Frontend/TextDiagnosticPrinter.h"
#include "clang/Serialization/ObjectFilePCHContainerReader.h"
#include "llvm/Support/VirtualFileSystem.h"

namespace clang {
class DiagnosticConsumer;

namespace dependencies {
class DependencyScanningService;
class DependencyScanningWorker;

class DependencyConsumer;
class DependencyActionController;
class DependencyScanningWorkerFilesystem;

class DependencyScanningAction {
public:
  DependencyScanningAction(
      DependencyScanningService &Service, StringRef WorkingDirectory,
      DependencyConsumer &Consumer, DependencyActionController &Controller,
      IntrusiveRefCntPtr<DependencyScanningWorkerFilesystem> DepFS,
      std::optional<StringRef> ModuleName = std::nullopt)
      : Service(Service), WorkingDirectory(WorkingDirectory),
        Consumer(Consumer), Controller(Controller), DepFS(std::move(DepFS)) {}
  bool runInvocation(std::string Executable,
                     std::unique_ptr<CompilerInvocation> Invocation,
                     IntrusiveRefCntPtr<llvm::vfs::FileSystem> FS,
                     std::shared_ptr<PCHContainerOperations> PCHContainerOps,
                     DiagnosticConsumer *DiagConsumer);

  bool hasScanned() const { return Scanned; }
  bool hasDiagConsumerFinished() const { return DiagConsumerFinished; }

private:
  DependencyScanningService &Service;
  StringRef WorkingDirectory;
  DependencyConsumer &Consumer;
  DependencyActionController &Controller;
  IntrusiveRefCntPtr<DependencyScanningWorkerFilesystem> DepFS;
  std::optional<CompilerInstance> ScanInstanceStorage;
  std::shared_ptr<ModuleDepCollector> MDC;
  bool Scanned = false;
  bool DiagConsumerFinished = false;
};

// Helper functions and data types.
std::unique_ptr<DiagnosticOptions>
createDiagOptions(ArrayRef<std::string> CommandLine);

struct DiagnosticsEngineWithDiagOpts {
  // We need to bound the lifetime of the DiagOpts used to create the
  // DiganosticsEngine with the DiagnosticsEngine itself.
  std::unique_ptr<DiagnosticOptions> DiagOpts;
  IntrusiveRefCntPtr<DiagnosticsEngine> DiagEngine;

  DiagnosticsEngineWithDiagOpts(ArrayRef<std::string> CommandLine,
                                IntrusiveRefCntPtr<llvm::vfs::FileSystem> FS,
                                DiagnosticConsumer &DC);
};

struct TextDiagnosticsPrinterWithOutput {
  // We need to bound the lifetime of the data that supports the DiagPrinter
  // with it together so they have the same lifetime.
  std::string DiagnosticOutput;
  llvm::raw_string_ostream DiagnosticsOS;
  std::unique_ptr<DiagnosticOptions> DiagOpts;
  TextDiagnosticPrinter DiagPrinter;

  TextDiagnosticsPrinterWithOutput(ArrayRef<std::string> CommandLine)
      : DiagnosticsOS(DiagnosticOutput),
        DiagOpts(createDiagOptions(CommandLine)),
        DiagPrinter(DiagnosticsOS, *DiagOpts) {}
};

std::unique_ptr<CompilerInvocation>
createCompilerInvocation(ArrayRef<std::string> CommandLine,
                         DiagnosticsEngine &Diags);

void initializeScanCompilerInstance(
    CompilerInstance &ScanInstance,
    IntrusiveRefCntPtr<llvm::vfs::FileSystem> FS,
    DiagnosticConsumer *DiagConsumer, DependencyScanningService &Service,
    IntrusiveRefCntPtr<DependencyScanningWorkerFilesystem> DepFS);

SmallVector<StringRef>
getInitialStableDirs(const CompilerInstance &ScanInstance);

std::optional<PrebuiltModulesAttrsMap>
computePrebuiltModulesASTMap(CompilerInstance &ScanInstance,
                             SmallVector<StringRef> &StableDirs);

/// Create the dependency collector that will collect the produced
/// dependencies. May return the created ModuleDepCollector depending
/// on the scanning format.
std::shared_ptr<ModuleDepCollector> initializeScanInstanceDependencyCollector(
    CompilerInstance &ScanInstance,
    std::unique_ptr<DependencyOutputOptions> DepOutputOpts,
    StringRef WorkingDirectory, DependencyConsumer &Consumer,
    DependencyScanningService &Service, CompilerInvocation &Inv,
    DependencyActionController &Controller,
    PrebuiltModulesAttrsMap PrebuiltModulesASTMap,
    llvm::SmallVector<StringRef> &StableDirs);

class CompilerInstanceWithContext {
  // Context
  DependencyScanningWorker &Worker;
  llvm::StringRef CWD;
  std::vector<std::string> CommandLine;

  // Context - Diagnostics engine.
  DiagnosticConsumer *DiagConsumer = nullptr;
  std::unique_ptr<DiagnosticsEngineWithDiagOpts> DiagEngineWithCmdAndOpts;

  // Context - compiler invocation
  std::unique_ptr<CompilerInvocation> OriginalInvocation;

  // Context - output options
  std::unique_ptr<DependencyOutputOptions> OutputOpts;

  // Context - stable directory handling
  llvm::SmallVector<StringRef> StableDirs;
  PrebuiltModulesAttrsMap PrebuiltModuleASTMap;

  // Compiler Instance
  std::unique_ptr<CompilerInstance> CIPtr;

  // Source location offset.
  int32_t SrcLocOffset = 0;

public:
  CompilerInstanceWithContext(DependencyScanningWorker &Worker, StringRef CWD,
                              const std::vector<std::string> &CMD)
      : Worker(Worker), CWD(CWD), CommandLine(CMD) {};

  // The three methods below returns false when they fail, with the detail
  // accumulated in \c DiagEngineWithDiagOpts's diagnostic consumer.
  bool initialize(
      std::unique_ptr<DiagnosticsEngineWithDiagOpts> DiagEngineWithDiagOpts,
      IntrusiveRefCntPtr<llvm::vfs::OverlayFileSystem> OverlayFS);
  bool computeDependencies(StringRef ModuleName, DependencyConsumer &Consumer,
                           DependencyActionController &Controller);
  bool finalize();
};
} // namespace dependencies
} // namespace clang

#endif // LLVM_CLANG_DEPENDENCYSCANNING_DEPENDENCYSCANNERIMPL_H