// Copyright (c) 2013 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef TOOLS_GN_NINJA_TARGET_WRITER_H_
#define TOOLS_GN_NINJA_TARGET_WRITER_H_

#include <iosfwd>

#include "base/basictypes.h"
#include "tools/gn/ninja_helper.h"
#include "tools/gn/path_output.h"

class FileTemplate;
class Settings;
class Target;

// Generates one target's ".ninja" file. The toplevel "build.ninja" file is
// generated by the NinjaBuildWriter.
class NinjaTargetWriter {
 public:
  NinjaTargetWriter(const Target* target,
                    const Toolchain* toolchain,
                    std::ostream& out);
  virtual ~NinjaTargetWriter();

  static void RunAndWriteFile(const Target* target, const Toolchain* toolchain);

  virtual void Run() = 0;

 protected:
  // Writes to the output stream a stamp rule for input dependencies, and
  // returns the string to be appended to source rules that encodes the
  // order-only dependencies for the current target. This will include the "|"
  // character so can just be appended to the source rules. If there are no
  // implicit dependencies and no extra target dependencies passed in, returns
  // the empty string.
  std::string WriteInputDepsStampAndGetDep(
      const std::vector<const Target*>& extra_hard_deps) const;

  // Returns the FileTemplate constructed from the outputs variable. This is
  // like FileTemplate::GetForTargetOutputs except this additionally trims the
  // build directory from the front so we can just write the names without
  // further processing.
  FileTemplate GetOutputTemplate() const;

  const Settings* settings_;  // Non-owning.
  const Target* target_;  // Non-owning.
  const Toolchain* toolchain_;  // Non-owning.
  std::ostream& out_;
  PathOutput path_output_;

  NinjaHelper helper_;

 private:
  void WriteCopyRules();

  DISALLOW_COPY_AND_ASSIGN(NinjaTargetWriter);
};

#endif  // TOOLS_GN_NINJA_TARGET_WRITER_H_