// file      : mod/mod-build-force.cxx -*- C++ -*-
// license   : MIT; see accompanying LICENSE file

#include <mod/mod-build-force.hxx>

#include <algorithm> // replace()

#include <odb/database.hxx>
#include <odb/transaction.hxx>

#include <web/server/module.hxx>

#include <libbrep/build.hxx>
#include <libbrep/build-odb.hxx>

#include <mod/module-options.hxx>

using namespace std;
using namespace bbot;
using namespace brep::cli;
using namespace odb::core;

// While currently the user-defined copy constructor is not required (we don't
// need to deep copy nullptr's), it is a good idea to keep the placeholder
// ready for less trivial cases.
//
brep::build_force::
build_force (const build_force& r)
    : database_module (r),
      build_config_module (r),
      options_ (r.initialized_ ? r.options_ : nullptr)
{
}

void brep::build_force::
init (scanner& s)
{
  HANDLER_DIAG;

  options_ = make_shared<options::build_force> (
    s, unknown_mode::fail, unknown_mode::fail);

  if (options_->build_config_specified ())
  {
    database_module::init (*options_, options_->build_db_retry ());
    build_config_module::init (*options_);
  }
}

bool brep::build_force::
handle (request& rq, response& rs)
{
  using brep::version; // Not to confuse with module::version.

  HANDLER_DIAG;

  if (build_db_ == nullptr)
    throw invalid_request (501, "not implemented");

  params::build_force params;

  try
  {
    name_value_scanner s (rq.parameters (8 * 1024));
    params = params::build_force (s, unknown_mode::fail, unknown_mode::fail);
  }
  catch (const cli::exception& e)
  {
    throw invalid_request (400, e.what ());
  }

  const string& reason (params.reason ());

  if (reason.empty ())
    throw invalid_request (400, "missing rebuild reason");

  build_id id;

  try
  {
    package_name p;

    try
    {
      p = package_name (move (params.package ()));
    }
    catch (const invalid_argument& e)
    {
      throw invalid_argument (string ("invalid package name: ") + e.what ());
    }

    // We accept the non-url-encoded version representation. Note that the
    // parameter is already url-decoded by the web server, so we just restore
    // the space character (that is otherwise forbidden in version
    // representation) to the plus character.
    //
    // @@ Move to types-parsers.hxx?
    //
    auto parse_version = [] (string& v, const char* what) -> version
    {
      replace (v.begin (), v.end (), ' ', '+');

      // Intercept exception handling to add the parsing error attribution.
      //
      try
      {
        return brep::version (v);
      }
      catch (const invalid_argument& e)
      {
        throw invalid_argument (string ("invalid ") + what + ": " + e.what ());
      }
    };

    version package_version (parse_version (params.version (),
                                            "package version"));

    string& config (params.configuration ());

    if (config.empty ())
      throw invalid_argument ("no configuration name");

    string& toolchain_name (params.toolchain_name ());

    if (toolchain_name.empty ())
      throw invalid_argument ("no toolchain name");

    version toolchain_version (parse_version (params.toolchain_version (),
                                              "toolchain version"));

    id = build_id (package_id (move (tenant), move (p), package_version),
                   move (config),
                   move (toolchain_name),
                   toolchain_version);
  }
  catch (const invalid_argument& e)
  {
    throw invalid_request (400, e.what ());
  }

  // If the package build configuration expired (no such configuration,
  // package, etc), then we respond with the 404 HTTP code (not found but may
  // be available in the future).
  //
  auto config_expired = [] (const string& d)
  {
    throw invalid_request (404, "package build configuration expired: " + d);
  };

  // Make sure the build configuration still exists.
  //
  if (build_conf_map_->find (id.configuration.c_str ()) ==
      build_conf_map_->end ())
    config_expired ("no configuration");

  // Load the package build configuration (if present), set the force flag and
  // update the object's persistent state.
  //
  {
    transaction t (build_db_->begin ());

    package_build pb;
    if (!build_db_->query_one<package_build> (
          query<package_build>::build::id == id, pb))
      config_expired ("no package build");

    shared_ptr<build> b (pb.build);
    force_state force (b->state == build_state::built
                       ? force_state::forced
                       : force_state::forcing);

    if (b->force != force)
    {
      b->force = force;
      build_db_->update (b);

      l1 ([&]{trace << "force rebuild for "
                    << b->tenant << ' '
                    << b->package_name << '/' << b->package_version << ' '
                    << b->configuration << ' '
                    << b->toolchain_name << '-' << b->toolchain_version
                    << ": " << reason;});
    }

    t.commit ();
  }

  // We have all the data, so don't buffer the response content.
  //
  ostream& os (rs.content (200, "text/plain;charset=utf-8", false));
  os << "Rebuilding in " << options_->build_forced_rebuild_timeout ()
     << " seconds.";

  return true;
}