/* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying

   file LICENSE.rst or https://cmake.org/licensing for details.  */

#include "cmTargetTraceDependencies.h"

#include <utility>

#include <cmext/algorithm>

#include <cmext/string_view>

#include "cmCustomCommand.h"

#include "cmCustomCommandGenerator.h"

#include "cmGeneratorTarget.h"

#include "cmGlobalGenerator.h"

#include "cmList.h"

#include "cmListFileCache.h"

#include "cmMakefile.h"

#include "cmMessageType.h"

#include "cmSourceFile.h"

#include "cmStringAlgorithms.h"

#include "cmSystemTools.h"

#include "cmTarget.h"

#include "cmTargetTypes.h"

#include "cmValue.h"

cmTargetTraceDependencies::cmTargetTraceDependencies(cmGeneratorTarget* target)

  : GeneratorTarget(target)

{

  // Convenience.

  this->Makefile = target->Target->GetMakefile();

  this->LocalGenerator = target->GetLocalGenerator();

  this->GlobalGenerator = this->LocalGenerator->GetGlobalGenerator();

  this->CurrentEntry = nullptr;

  // Queue all the source files already specified for the target.

  std::set<cmSourceFile*> emitted;

  std::vector<std::string> const& configs =

    this->Makefile->GetGeneratorConfigs(cmMakefile::IncludeEmptyConfig);

  for (std::string const& c : configs) {

    std::vector<cmSourceFile*> sources;

    this->GeneratorTarget->GetSourceFiles(sources, c);

    for (cmSourceFile* sf : sources) {

      std::set<cmGeneratorTarget const*> const tgts =

        this->GlobalGenerator->GetFilenameTargetDepends(sf);

      if (cm::contains(tgts, this->GeneratorTarget)) {

        this->GeneratorTarget->LocalGenerator->IssueMessage(

          MessageType::FATAL_ERROR,

          cmStrCat("Evaluation output file\n  \"", sf->ResolveFullPath(),

                   "\"\ndepends on the sources of a target it is used in.  "

                   "This is a dependency loop and is not allowed."));

        return;

      }

      if (emitted.insert(sf).second && this->SourcesQueued.insert(sf).second) {

        this->SourceQueue.push(sf);

      }

    }

  }

  // Queue pre-build, pre-link, and post-build rule dependencies.

  this->CheckCustomCommands(this->GeneratorTarget->GetPreBuildCommands());

  this->CheckCustomCommands(this->GeneratorTarget->GetPreLinkCommands());

  this->CheckCustomCommands(this->GeneratorTarget->GetPostBuildCommands());

}

void cmTargetTraceDependencies::Trace()

{

  // Process one dependency at a time until the queue is empty.

  while (!this->SourceQueue.empty()) {

    // Get the next source from the queue.

    cmSourceFile* sf = this->SourceQueue.front();

    this->SourceQueue.pop();

    this->CurrentEntry = &this->GeneratorTarget->SourceDepends[sf];

    // Queue dependencies added explicitly by the user.

    if (cmValue additionalDeps = sf->GetProperty("OBJECT_DEPENDS")) {

      cmList objDeps{ *additionalDeps };

      for (auto& objDep : objDeps) {

        if (cmSystemTools::FileIsFullPath(objDep)) {

          objDep = cmSystemTools::CollapseFullPath(objDep);

        }

      }

      this->FollowNames(objDeps);

    }

    // Queue the source needed to generate this file, if any.

    this->FollowName(sf->ResolveFullPath());

    // Queue dependencies added programmatically by commands.

    this->FollowNames(sf->GetDepends());

    // Queue custom command dependencies.

    if (cmCustomCommand const* cc = sf->GetCustomCommand()) {

      this->CheckCustomCommand(*cc);

    }

  }

  this->CurrentEntry = nullptr;

  this->GeneratorTarget->AddTracedSources(this->NewSources);

}

void cmTargetTraceDependencies::QueueSource(cmSourceFile* sf)

{

  if (this->SourcesQueued.insert(sf).second) {

    this->SourceQueue.push(sf);

    // Make sure this file is in the target at the end.

    this->NewSources.push_back(sf->ResolveFullPath());

  }

}

void cmTargetTraceDependencies::FollowName(std::string const& name)

{

  // Use lower bound with key comparison to not repeat the search for the

  // insert position if the name could not be found (which is the common case).

  auto i = this->NameMap.lower_bound(name);

  if (i == this->NameMap.end() || i->first != name) {

    // Check if we know how to generate this file.

    cmSourcesWithOutput sources =

      this->LocalGenerator->GetSourcesWithOutput(name);

    // If we failed to find a target or source and we have a relative path, it

    // might be a valid source if made relative to the current binary

    // directory.

    if (!sources.Target && !sources.Source &&

        !cmSystemTools::FileIsFullPath(name)) {

      auto fullname =

        cmStrCat(this->Makefile->GetCurrentBinaryDirectory(), '/', name);

      fullname = cmSystemTools::CollapseFullPath(

        fullname, this->Makefile->GetHomeOutputDirectory());

      sources = this->LocalGenerator->GetSourcesWithOutput(fullname);

    }

    i = this->NameMap.emplace_hint(i, name, sources);

  }

  if (cmTarget* t = i->second.Target) {

    // The name is a byproduct of a utility target or a PRE_BUILD, PRE_LINK, or

    // POST_BUILD command.

    this->GeneratorTarget->Target->AddUtility(t->GetName(), false);

    this->GeneratorTarget->Target->AddCodegenDependency(t->GetName());

  }

  if (cmSourceFile* sf = i->second.Source) {

    // For now only follow the dependency if the source file is not a

    // byproduct.  Semantics of byproducts in a non-Ninja context will have to

    // be defined first.

    if (!i->second.SourceIsByproduct) {

      // Record the dependency we just followed.

      if (this->CurrentEntry) {

        this->CurrentEntry->Depends.push_back(sf);

      }

      this->QueueSource(sf);

    }

  }

}

void cmTargetTraceDependencies::FollowNames(

  std::vector<std::string> const& names)

{

  for (std::string const& name : names) {

    this->FollowName(name);

  }

}

bool cmTargetTraceDependencies::IsUtility(std::string const& dep)

{

  // Dependencies on targets (utilities) are supposed to be named by

  // just the target name.  However for compatibility we support

  // naming the output file generated by the target (assuming there is

  // no output-name property which old code would not have set).  In

  // that case the target name will be the file basename of the

  // dependency.

  std::string util;

  if (cmHasSuffix(dep, ".exe"_s)) {

    util = cmSystemTools::GetFilenameWithoutLastExtension(dep);

  } else {

    util = cmSystemTools::GetFilenameName(dep);

  }

  // Check for a target with this name.

  if (cmGeneratorTarget* t =

        this->GeneratorTarget->GetLocalGenerator()->FindGeneratorTargetToUse(

          util)) {

    // If we find the target and the dep was given as a full path,

    // then make sure it was not a full path to something else, and

    // the fact that the name matched a target was just a coincidence.

    if (cmSystemTools::FileIsFullPath(dep)) {

      if (t->GetType() >= cm::TargetType::EXECUTABLE &&

          t->GetType() <= cm::TargetType::MODULE_LIBRARY) {

        // This is really only for compatibility so we do not need to

        // worry about configuration names and output names.

        std::string tLocation = t->GetLocationForBuild();

        tLocation = cmSystemTools::GetFilenamePath(tLocation);

        std::string depLocation = cmSystemTools::GetFilenamePath(dep);

        depLocation = cmSystemTools::CollapseFullPath(depLocation);

        tLocation = cmSystemTools::CollapseFullPath(tLocation);

        if (depLocation == tLocation) {

          this->GeneratorTarget->Target->AddUtility(util, false);

          return true;

        }

      }

    } else {

      // The original name of the dependency was not a full path.  It

      // must name a target, so add the target-level dependency.

      this->GeneratorTarget->Target->AddUtility(util, true);

      return true;

    }

  }

  // The dependency does not name a target built in this project.

  return false;

}

void cmTargetTraceDependencies::CheckCustomCommand(cmCustomCommand const& cc)

{

  // Collect dependencies referenced by all configurations.

  std::set<std::string> depends;

  for (std::string const& config :

       this->Makefile->GetGeneratorConfigs(cmMakefile::IncludeEmptyConfig)) {

    for (cmCustomCommandGenerator const& ccg :

         this->LocalGenerator->MakeCustomCommandGenerators(cc, config)) {

      // Collect target-level dependencies referenced in command lines.

      for (auto const& util : ccg.GetUtilities()) {

        this->GeneratorTarget->Target->AddUtility(util);

        if (ccg.GetCC().GetCodegen()) {

          this->GeneratorTarget->Target->AddCodegenDependency(

            util.Value.first);

        }

      }

      // Collect file-level dependencies referenced in DEPENDS.

      depends.insert(ccg.GetDepends().begin(), ccg.GetDepends().end());

    }

  }

  // Queue file-level dependencies.

  for (std::string const& dep : depends) {

    if (!this->IsUtility(dep)) {

      // The dependency does not name a target and may be a file we

      // know how to generate.  Queue it.

      this->FollowName(dep);

    } else {

      this->GeneratorTarget->Target->AddCodegenDependency(dep);

    }

  }

}

void cmTargetTraceDependencies::CheckCustomCommands(

  std::vector<cmCustomCommand> const& commands)

{

  for (cmCustomCommand const& command : commands) {

    this->CheckCustomCommand(command);

  }

}