// file      : bpkg/package.cxx -*- C++ -*-
// license   : MIT; see accompanying LICENSE file

#include <bpkg/package.hxx>
#include <bpkg/package-odb.hxx>

#include <bpkg/database.hxx>
#include <bpkg/checksum.hxx>
#include <bpkg/rep-mask.hxx>
#include <bpkg/pkg-verify.hxx>
#include <bpkg/diagnostics.hxx>
#include <bpkg/satisfaction.hxx>
#include <bpkg/manifest-utility.hxx>

using namespace std;

namespace bpkg
{
  const version wildcard_version (0, "0", nullopt, nullopt, 0);

  // configuration
  //
  configuration::
  configuration (optional<string> n, string t, optional<uuid_type> uid)
      : id (0),
        name (move (n)),
        type (move (t)),
        expl (false)
  {
    try
    {
      uuid = uid ? *uid : uuid_type::generate ();
    }
    catch (const system_error& e)
    {
      fail << "unable to generate configuration uuid: " << e;
    }
  }

  dir_path configuration::
  effective_path (const dir_path& d) const
  {
    if (path.relative ())
    {
      dir_path r (d / path);

      string what ("linked with " + d.representation () + " configuration " +
                   (name ? *name : to_string (*id)));

      normalize (r, what.c_str ());
      return r;
    }
    else
      return path;
  }

  // package_key
  //
  string package_key::
  string () const
  {
    const std::string& s (db.get ().string);
    return !s.empty () ? name.string () + ' ' + s : name.string ();
  }

  bool package_key::
  operator< (const package_key& v) const
  {
    int r (name.compare (v.name));
    return r != 0 ? (r < 0) : (db < v.db);
  }

  // available_package
  //
  const version* available_package::
  system_version (database& db) const
  {
    if (!system_version_)
    {
      assert (db.system_repository);

      if (const system_package* sp = db.system_repository->find (id.name))
      {
        // Only cache if it is authoritative.
        //
        if (sp->authoritative)
          system_version_ = sp->version;
        else
          return &sp->version;
      }
    }

    return system_version_ ? &*system_version_ : nullptr;
  }

  pair<const version*, bool> available_package::
  system_version_authoritative (database& db) const
  {
    assert (db.system_repository);

    const system_package* sp (db.system_repository->find (id.name));

    if (!system_version_)
    {
      if (sp != nullptr)
      {
        // Only cache if it is authoritative.
        //
        if (sp->authoritative)
          system_version_ = sp->version;
        else
          return make_pair (&sp->version, false);
      }
    }

    return make_pair (system_version_ ?  &*system_version_ : nullptr,
                      sp != nullptr ? sp->authoritative : false);
  }

  void
  check_any_available (const linked_databases& dbs,
                       transaction&,
                       const diag_record* drp)
  {
    bool rep (false);
    bool pkg (false);
    for (database& db: dbs)
    {
      if (db.query_value<repository_count> () != 0)
      {
        rep = true;

        if (db.query_value<available_package_count> () != 0)
        {
          pkg = true;
          break;
        }
      }
    }

    if (pkg)
      return;

    diag_record d;
    const diag_record& dr (drp != nullptr ? *drp << info : d << fail);

    if (dbs.size () == 1)
      dr << "configuration " << dbs[0].get ().config_orig << " has ";
    else
      dr << "specified configurations have ";

    if (!rep)
    {
      dr << "no repositories" <<
        info << "use 'bpkg rep-add' to add a repository";
    }
    else
    {
      dr << "no available packages" <<
        info << "use 'bpkg rep-fetch' to fetch available packages list";
    }
  }

  void
  check_any_available (database& db, transaction& t, const diag_record* dr)
  {
    return check_any_available (linked_databases ({db}), t, dr);
  }

  string
  package_string (const package_name& n, const version& v, bool system)
  {
    assert (!n.empty ());

    string vs (v.empty ()
               ? string ()
               : v == wildcard_version
                 ? "/*"
                 : '/' + v.string ());

    return system ? "sys:" + n.string () + vs : n.string () + vs;
  }

  string
  package_string (const package_name& name,
                  const optional<version_constraint>& constraint,
                  bool system)
  {
    // Fallback to the version type-based overload if the constraint is not
    // specified.
    //
    if (!constraint)
      return package_string (name, version (), system);

    // There are no scenarios where the version constrain is present but is
    // empty (both endpoints are nullopt).
    //
    assert (!constraint->empty ());

    // If the endpoint versions are equal then represent the constraint as the
    // "<name>/<version>" string rather than "<name> == <version>", using the
    // version type-based overload.
    //
    const optional<version>& min_ver (constraint->min_version);
    bool eq (min_ver == constraint->max_version);

    if (eq)
      return package_string (name, *min_ver, system);

    if (system)
      return package_string (name, version (), system) + "/...";

    // Quote the result as it contains the space character.
    //
    return '\'' + name.string () + ' ' + constraint->string () + '\'';
  }

  // selected_package
  //
  string selected_package::
  string (database& db) const
  {
    const std::string& s (db.string);
    return !s.empty () ? string () + ' ' + s : string ();
  }

  _selected_package_ref::
  _selected_package_ref (const lazy_shared_ptr<selected_package>& p)
      : configuration (p.database ().uuid),
        prerequisite (p.object_id ())
  {
  }

  lazy_shared_ptr<selected_package> _selected_package_ref::
  to_ptr (odb::database& db) &&
  {
    database& pdb (static_cast<database&> (db));

    // Note that if this points to a different configuration, then it should
    // already be pre-attached since it must be explicitly linked.
    //
    database& ddb (pdb.find_dependency_config (configuration));

    // Make sure the prerequisite exists in the explicitly linked
    // configuration, so that a subsequent load() call will not fail. This,
    // for example, can happen in unlikely but possible situation when the
    // implicitly linked configuration containing a dependent was temporarily
    // renamed before its prerequisite was dropped.
    //
    // Note that the diagnostics lacks information about the dependent and its
    // configuration. However, handling this situation at all the load()
    // function call sites where this information is available, for example by
    // catching the odb::object_not_persistent exception, feels a bit
    // hairy. Given the situation is not common, let's keep it simple for now
    // and see how it goes.
    //
    if (ddb != pdb && ddb.find<selected_package> (prerequisite) == nullptr)
      fail << "unable to find prerequisite package " << prerequisite
           << " in linked configuration " << ddb.config_orig;

    return lazy_shared_ptr<selected_package> (ddb, move (prerequisite));
  }

  string
  to_string (config_source s)
  {
    switch (s)
    {
    case config_source::user:      return "user";
    case config_source::dependent: return "dependent";
    case config_source::reflect:   return "reflect";
    }

    return string (); // Should never reach.
  }

  config_source
  to_config_source (const string& s)
  {
         if (s == "user")      return config_source::user;
    else if (s == "dependent") return config_source::dependent;
    else if (s == "reflect")   return config_source::reflect;
    else throw invalid_argument ("invalid config source '" + s + '\'');
  }

  shared_ptr<available_package>
  make_available (const common_options& options,
                  database& db,
                  const shared_ptr<selected_package>& sp)
  {
    assert (sp != nullptr && sp->state != package_state::broken);

    if (sp->system ())
      return make_shared<available_package> (sp->name, sp->version);

    // The package is in at least fetched state, which means we should
    // be able to get its manifest.
    //
    const optional<path>& a (sp->archive);

    package_manifest m (
      sp->state == package_state::fetched
      ? pkg_verify (options,
                    a->absolute () ? *a : db.config_orig / *a,
                    true /* ignore_unknown */,
                    false /* ignore_toolchain */,
                    false /* expand_values */,
                    true /* load_buildfiles */)
      : pkg_verify (options,
                    sp->effective_src_root (db.config_orig),
                    true /* ignore_unknown */,
                    false /* ignore_toolchain */,
                    true /* load_buildfiles */,
                    // Copy potentially fixed up version from selected package.
                    [&sp] (version& v) {v = sp->version;}));

    return make_shared<available_package> (move (m));
  }

  pair<shared_ptr<selected_package>, database*>
  find_dependency (database& db, const package_name& pn, bool buildtime)
  {
    pair<shared_ptr<selected_package>, database*> r;

    for (database& ldb: db.dependency_configs (pn, buildtime))
    {
      shared_ptr<selected_package> p (ldb.find<selected_package> (pn));

      if (p != nullptr)
      {
        if (r.first == nullptr)
        {
          r.first = move (p);
          r.second = &ldb;
        }
        else
        {
          fail << "package " << pn << " appears in multiple configurations" <<
            info << r.first->state << " in " << r.second->config_orig <<
            info << p->state << " in " << ldb.config_orig;
        }
      }
    }

    return r;
  }

  optional<version>
  package_iteration (const common_options& o,
                     database& db,
                     transaction&,
                     const dir_path& d,
                     const package_name& n,
                     const version& v,
                     const package_info* pi,
                     bool check_external)
  {
    tracer trace ("package_iteration");

    tracer_guard tg (db, trace);

    if (check_external)
    {
      using query = query<package_repository_fragment>;

      query q (
        query::package::id.name == n &&
        compare_version_eq (query::package::id.version,
                            canonical_version (v),
                            true /* revision */,
                            false /* iteration */));

      for (const auto& prf: db.query<package_repository_fragment> (q))
      {
        const shared_ptr<repository_fragment>& rf (prf.repository_fragment);

        if (!rep_masked_fragment (db, rf) && rf->location.directory_based ())
          fail << "external package " << n << '/' << v
               << " is already available from "
               << rf->location.canonical_name ();
      }
    }

    shared_ptr<selected_package> p (db.find<selected_package> (n));

    if (p == nullptr || !p->src_root ||
        compare_version_ne (v,
                            p->version,
                            true /* revision */,
                            false /* iteration */))
      return nullopt;

    bool changed (!p->external ());

    // If the selected package is not external, then increment the iteration
    // number to make the external package preferable. Note that for such
    // packages the manifest/subprojects and buildfiles checksums are absent.
    //
    if (!changed)
    {
      // The selected package must not be "simulated" (see pkg-build for
      // details).
      //
      assert (p->manifest_checksum);

      changed = (package_checksum (o, d, pi) != *p->manifest_checksum);

      // If the manifest hasn't changed and the package has buildfile clauses
      // in the dependencies, then check if the buildfiles haven't changed
      // either.
      //
      if (!changed && p->buildfiles_checksum)
      {
        // Always calculate the checksum over the buildfiles since the package
        // is external.
        //
        changed = package_buildfiles_checksum (
          nullopt /* bootstrap_build */,
          nullopt /* root_build */,
          {}      /* buildfiles */,
          d) != *p->buildfiles_checksum;
      }

      // If the manifest hasn't changed but the selected package points to an
      // external source directory, then we also check if the directory have
      // moved.
      //
      if (!changed)
      {
        dir_path src_root (p->effective_src_root (db.config));

        // We need to complete and normalize the source directory as it may
        // generally be completed against the configuration directory
        // (unlikely but possible), that can be relative and/or not
        // normalized.
        //
        normalize (src_root, "package source");

        changed = src_root != normalize (d, "package source");
      }
    }

    return !changed
      ? p->version
      : version (v.epoch,
                 v.upstream,
                 v.release,
                 v.revision,
                 p->version.iteration + 1);
  }

  // state
  //
  string
  to_string (package_state s)
  {
    switch (s)
    {
    case package_state::transient:  return "transient";
    case package_state::broken:     return "broken";
    case package_state::fetched:    return "fetched";
    case package_state::unpacked:   return "unpacked";
    case package_state::configured: return "configured";
    }

    return string (); // Should never reach.
  }

  package_state
  to_package_state (const string& s)
  {
         if (s == "transient")  return package_state::transient;
    else if (s == "broken")     return package_state::broken;
    else if (s == "fetched")    return package_state::fetched;
    else if (s == "unpacked")   return package_state::unpacked;
    else if (s == "configured") return package_state::configured;
    else throw invalid_argument ("invalid package state '" + s + '\'');
  }

  // substate
  //
  string
  to_string (package_substate s)
  {
    switch (s)
    {
    case package_substate::none:   return "none";
    case package_substate::system: return "system";
    }

    return string (); // Should never reach.
  }

  package_substate
  to_package_substate (const string& s)
  {
         if (s == "none")   return package_substate::none;
    else if (s == "system") return package_substate::system;
    else throw invalid_argument ("invalid package substate '" + s + '\'');
  }

  // certificate
  //
  ostream&
  operator<< (ostream& os, const certificate& c)
  {
    using butl::operator<<;

    if (c.dummy ())
      os << c.name << " (dummy)";
    else
      os << c.name << ", \"" << c.organization << "\" <" << c.email << ">, "
         << c.start_date << " - " << c.end_date << ", " << c.fingerprint;

    return os;
  }

  // package_dependent
  //
  odb::result<package_dependent>
  query_dependents (database& db,
                    const package_name& dep,
                    database& dep_db)
  {
    // Prepare and cache this query since it's executed a lot. Note that we
    // have to cache one per database.
    //
    using query = query<package_dependent>;
    using prep_query = prepared_query<package_dependent>;

    struct params
    {
      string name;
      string config;     // Configuration UUID.
      string query_name;
    };

    params*    qp;
    string     qn (db.uuid.string () + "-package-dependent-query");
    prep_query pq (db.lookup_query<package_dependent> (qn.c_str (), qp));

    if (!pq)
    {
      unique_ptr<params> p (qp = new params ());
      p->query_name = move (qn);

      query q ("prerequisite = " + query::_ref (p->name) + "AND" +
               "configuration = " + query::_ref (p->config));

      pq = db.prepare_query<package_dependent> (p->query_name.c_str (), q);
      db.cache_query (pq, move (p));
    }

    qp->name   = dep.string ();
    qp->config = dep_db.uuid.string ();

    return pq.execute ();
  }

  vector<package_dependent>
  query_dependents_cache (database& db,
                          const package_name& dep,
                          database& dep_db)
  {
    vector<package_dependent> r;
    for (package_dependent& pd: query_dependents (db, dep, dep_db))
      r.push_back (move (pd));
    return r;
  }

  bool
  toolchain_buildtime_dependency (const common_options& o,
                                  const dependency_alternatives& das,
                                  const package_name* pkg)
  {
    if (das.buildtime)
    {
      for (const dependency_alternative& da: das)
      {
        for (const dependency& d: da)
        {
          const package_name& dn (d.name);

          if (dn == "build2")
          {
            if (pkg != nullptr && d.constraint && !satisfy_build2 (o, d))
            {
              fail << "unable to satisfy constraint (" << d << ") for "
                   << "package " << *pkg <<
                info << "available build2 version is " << build2_version;
            }

            return true;
          }
          else if (dn == "bpkg")
          {
            if (pkg != nullptr && d.constraint && !satisfy_bpkg (o, d))
            {
              fail << "unable to satisfy constraint (" << d << ") for "
                   << "package " << *pkg <<
                info << "available bpkg version is " << bpkg_version;
            }

            return true;
          }
        }
      }
    }

    return false;
  }

  bool
  has_dependencies (const common_options& o,
                    const dependencies& deps,
                    const package_name* pkg)
  {
    for (const auto& das: deps)
    {
      if (!toolchain_buildtime_dependency (o, das, pkg))
        return true;
    }

    return false;
  }
}
