// file      : odb/generator.cxx
// copyright : Copyright (c) 2009-2013 Code Synthesis Tools CC
// license   : GNU GPL v3; see accompanying LICENSE file

#include <cctype>  // std::toupper, std::is{alpha,upper,lower}
#include <string>
#include <memory>  // std::auto_ptr
#include <fstream>
#include <sstream>
#include <iostream>

#include <cutl/fs/auto-remove.hxx>

#include <cutl/compiler/code-stream.hxx>
#include <cutl/compiler/cxx-indenter.hxx>
#include <cutl/compiler/sloc-counter.hxx>

#include <cutl/xml/parser.hxx>
#include <cutl/xml/serializer.hxx>

#include <odb/version.hxx>
#include <odb/context.hxx>
#include <odb/generator.hxx>

#include <odb/semantics/relational/model.hxx>
#include <odb/semantics/relational/changelog.hxx>

#include <odb/generate.hxx>
#include <odb/relational/generate.hxx>

using namespace std;
using namespace cutl;

using semantics::path;
typedef vector<string> strings;
typedef vector<path> paths;

namespace
{
  static char const cxx_file_header[] =
    "// This file was generated by ODB, object-relational mapping (ORM)\n"
    "// compiler for C++.\n"
    "//\n\n";

  static char const sql_file_header[] =
    "/* This file was generated by ODB, object-relational mapping (ORM)\n"
    " * compiler for C++.\n"
    " */\n\n";

  void
  open (ifstream& ifs, string const& path)
  {
    ifs.open (path.c_str (), ios_base::in | ios_base::binary);

    if (!ifs.is_open ())
    {
      cerr << path << ": error: unable to open in read mode" << endl;
      throw generator::failed ();
    }
  }

  void
  append (ostream& os, strings const& text)
  {
    for (strings::const_iterator i (text.begin ());
         i != text.end (); ++i)
    {
      os << *i << endl;
    }
  }

  void
  append (ostream& os, string const& file)
  {
    ifstream ifs;
    open (ifs, file);
    os << ifs.rdbuf ();
  }
}

void generator::
generate (options const& ops,
          features& fts,
          semantics::unit& unit,
          path const& p,
          paths const& inputs)
{
  try
  {
    database db (ops.database ()[0]);
    multi_database md (ops.multi_database ());

    // First create the database model.
    //
    bool gen_schema (ops.generate_schema () && db != database::common);
    cutl::shared_ptr<semantics::relational::model> model;

    if (gen_schema)
    {
      auto_ptr<context> ctx (create_context (cerr, unit, ops, fts, 0));

      switch (db)
      {
      case database::mssql:
      case database::mysql:
      case database::oracle:
      case database::pgsql:
      case database::sqlite:
        {
          model = relational::model::generate ();
          break;
        }
      case database::common:
        break;
      }
    }

    // Output files.
    //
    fs::auto_removes auto_rm;

    path file (ops.input_name ().empty ()
               ? p.leaf ()
               : path (ops.input_name ()).leaf ());
    string base (file.base ().string ());

    string hxx_name (base + ops.odb_file_suffix ()[db] + ops.hxx_suffix ());
    string ixx_name (base + ops.odb_file_suffix ()[db] + ops.ixx_suffix ());
    string cxx_name (base + ops.odb_file_suffix ()[db] + ops.cxx_suffix ());
    string sch_name (base + ops.schema_file_suffix ()[db] + ops.cxx_suffix ());
    string sql_name (base + ops.sql_file_suffix ()[db] + ops.sql_suffix ());

    path hxx_path (hxx_name);
    path ixx_path (ixx_name);
    path cxx_path (cxx_name);
    path sch_path (sch_name);
    path sql_path (sql_name);

    if (!ops.output_dir ().empty ())
    {
      path dir (ops.output_dir ());
      hxx_path = dir / hxx_path;
      ixx_path = dir / ixx_path;
      cxx_path = dir / cxx_path;
      sch_path = dir / sch_path;
      sql_path = dir / sql_path;
    }

    path in_log_path, out_log_path;
    path log_dir (ops.changelog_dir ().empty () ? "" : ops.changelog_dir ());
    if (ops.changelog_in_specified ())
    {
      in_log_path = path (ops.changelog_in ());
      out_log_path = path (ops.changelog_out ());

      if (!log_dir.empty ())
      {
        if (!in_log_path.absolute ())
          in_log_path = log_dir / in_log_path;

        if (!out_log_path.absolute ())
          out_log_path = log_dir / out_log_path;
      }
    }
    else if (ops.changelog_specified ())
    {
      in_log_path = path (ops.changelog ());

      if (!in_log_path.absolute () && !log_dir.empty ())
        in_log_path = log_dir / in_log_path;

      out_log_path = in_log_path;
    }
    else
    {
      string log_name (base + ops.changelog_file_suffix ()[db] +
                       ops.changelog_suffix ());
      in_log_path = path (log_name);

      if (!log_dir.empty ())
        in_log_path = log_dir / in_log_path;
      else
        in_log_path = p.directory () / in_log_path; // Use input directory.

      out_log_path = in_log_path;
    }

    // Load the old changelog and generate a new one.
    //
    bool gen_log (gen_schema && unit.count ("model-version") != 0);
    cutl::shared_ptr<semantics::relational::changelog> changelog;
    cutl::shared_ptr<semantics::relational::changelog> old_changelog;
    string old_changelog_xml;

    if (gen_log)
    {
      ifstream log (in_log_path.string ().c_str (),
                    ios_base::in | ios_base::binary);

      if (log.is_open ())
      {
        try
        {
          // Get the XML into a buffer. We use it to avoid modifying the
          // file when the changelog hasn't changed.
          //
          for (bool first (true); !log.eof (); )
          {
            string line;
            getline (log, line);

            if (log.fail ())
              ios_base::failure ("getline");

            if (first)
              first = false;
            else
              old_changelog_xml += '\n';

            old_changelog_xml += line;
          }

          istringstream is (old_changelog_xml);
          is.exceptions (ios_base::badbit | ios_base::failbit);

          xml::parser p (is, in_log_path.string ());
          old_changelog.reset (
            new (shared) semantics::relational::changelog (p));
        }
        catch (const ios_base::failure& e)
        {
          cerr << in_log_path << ": read failure" << endl;
          throw failed ();
        }
        catch (const xml::parsing& e)
        {
          cerr << e.what () << endl;
          throw failed ();
        }
      }

      changelog = relational::changelog::generate (
        *model,
        unit.get<model_version> ("model-version"),
        old_changelog.get (),
        in_log_path.string (),
        out_log_path.string ());
    }

    //
    //
    bool gen_cxx (!ops.generate_schema_only ());

    ofstream hxx;
    if (gen_cxx)
    {
      hxx.open (hxx_path.string ().c_str (), ios_base::out);

      if (!hxx.is_open ())
      {
        cerr << "error: unable to open '" << hxx_path << "' in write mode"
             << endl;
        throw failed ();
      }

      auto_rm.add (hxx_path);
    }

    //
    //
    ofstream ixx;
    if (gen_cxx)
    {
      ixx.open (ixx_path.string ().c_str (), ios_base::out);

      if (!ixx.is_open ())
      {
        cerr << "error: unable to open '" << ixx_path << "' in write mode"
             << endl;
        throw failed ();
      }

      auto_rm.add (ixx_path);
    }

    //
    //
    ofstream cxx;
    if (gen_cxx && (db != database::common || md == multi_database::dynamic))
    {
      cxx.open (cxx_path.string ().c_str (), ios_base::out);

      if (!cxx.is_open ())
      {
        cerr << "error: unable to open '" << cxx_path << "' in write mode"
             << endl;
        throw failed ();
      }

      auto_rm.add (cxx_path);
    }

    //
    //
    bool gen_sql_schema (gen_schema &&
                         ops.schema_format ()[db].count (schema_format::sql));
    ofstream sql;
    if (gen_sql_schema)
    {
      sql.open (sql_path.string ().c_str (), ios_base::out);

      if (!sql.is_open ())
      {
        cerr << "error: unable to open '" << sql_path << "' in write mode"
             << endl;
        throw failed ();
      }

      auto_rm.add (sql_path);
    }

    //
    //
    bool gen_sep_schema (
      gen_cxx &&
      gen_schema &&
      ops.schema_format ()[db].count (schema_format::separate));

    ofstream sch;
    if (gen_sep_schema)
    {
      sch.open (sch_path.string ().c_str (), ios_base::out);

      if (!sch.is_open ())
      {
        cerr << "error: unable to open '" << sch_path << "' in write mode"
             << endl;
        throw failed ();
      }

      auto_rm.add (sch_path);
    }

    // Print C++ headers.
    //
    if (gen_cxx)
    {
      hxx << cxx_file_header;
      ixx << cxx_file_header;

      if (db != database::common)
        cxx << cxx_file_header;
    }

    if (gen_sep_schema)
      sch << cxx_file_header;

    if (gen_sql_schema)
      sql << sql_file_header;

    typedef compiler::ostream_filter<compiler::cxx_indenter, char> ind_filter;
    typedef compiler::ostream_filter<compiler::sloc_counter, char> sloc_filter;

    size_t sloc_total (0);

    // Include settings.
    //
    string gp (ops.guard_prefix ());
    if (!gp.empty () && gp[gp.size () - 1] != '_')
      gp.append ("_");

    // HXX
    //
    if (gen_cxx)
    {
      auto_ptr<context> ctx (
        create_context (hxx, unit, ops, fts, model.get ()));

      sloc_filter sloc (ctx->os);

      string guard (ctx->make_guard (gp + hxx_name));

      hxx << "#ifndef " << guard << endl
          << "#define " << guard << endl
          << endl;

      // Version check.
      //
      hxx << "#include <odb/version.hxx>" << endl
          << endl
          << "#if (ODB_VERSION != " << ODB_VERSION << "UL)" << endl
          << "#error ODB runtime version mismatch" << endl
          << "#endif" << endl
          << endl;

      hxx << "#include <odb/pre.hxx>" << endl
          << endl;

      // Copy prologue.
      //
      {
        bool p (ops.hxx_prologue ().count (db) != 0);
        bool pf (ops.hxx_prologue_file ().count (db) != 0);

        if (p || pf)
        {
          hxx << "// Begin prologue." << endl
              << "//" << endl;
          if (p)
            append (hxx, ops.hxx_prologue ()[db]);
          if (pf)
            append (hxx, ops.hxx_prologue_file ()[db]);
          hxx << "//" << endl
              << "// End prologue." << endl
              << endl;
        }
      }

      // Include main file(s).
      //
      for (paths::const_iterator i (inputs.begin ()); i != inputs.end (); ++i)
        hxx << "#include " <<
          ctx->process_include_path (i->leaf ().string ()) << endl;
      hxx << endl;

      {
        // We don't want to indent prologues/epilogues.
        //
        ind_filter ind (ctx->os);

        // There are no -odb.hxx includes if we are generating code for
        // everything.
        //
        if (!ops.at_once ())
          include::generate (true);

        switch (db)
        {
        case database::common:
          {
            header::generate ();
            break;
          }
        case database::mssql:
        case database::mysql:
        case database::oracle:
        case database::pgsql:
        case database::sqlite:
          {
            if (md == multi_database::disabled)
              header::generate ();
            else
            {
              string n (base +
                        ops.odb_file_suffix ()[database::common] +
                        ops.hxx_suffix ());

              hxx << "#include " << ctx->process_include_path (n) << endl
                  << endl;
            }

            relational::header::generate ();
            break;
          }
        }
      }

      hxx << "#include " << ctx->process_include_path (ixx_name) << endl
          << endl;

      // Copy epilogue.
      //
      {
        bool e (ops.hxx_epilogue ().count (db) != 0);
        bool ef (ops.hxx_epilogue_file ().count (db) != 0);

        if (e || ef)
        {
          hxx << "// Begin epilogue." << endl
              << "//" << endl;
          if (e)
            append (hxx, ops.hxx_epilogue ()[db]);
          if (ef)
            append (hxx, ops.hxx_epilogue_file ()[db]);
          hxx << "//" << endl
              << "// End epilogue." << endl
              << endl;
        }
      }

      hxx << "#include <odb/post.hxx>" << endl
          << endl;

      hxx << "#endif // " << guard << endl;

      if (ops.show_sloc ())
        cerr << hxx_name << ": " << sloc.stream ().count () << endl;

      sloc_total += sloc.stream ().count ();
    }

    // IXX
    //
    if (gen_cxx)
    {
      auto_ptr<context> ctx (
        create_context (ixx, unit, ops, fts, model.get ()));

      sloc_filter sloc (ctx->os);

      // Copy prologue.
      //
      {
        bool p (ops.ixx_prologue ().count (db) != 0);
        bool pf (ops.ixx_prologue_file ().count (db) != 0);

        if (p || pf)
        {
          ixx << "// Begin prologue." << endl
              << "//" << endl;
          if (p)
            append (ixx, ops.ixx_prologue ()[db]);
          if (pf)
            append (ixx, ops.ixx_prologue_file ()[db]);
          ixx << "//" << endl
              << "// End prologue." << endl
              << endl;
        }
      }

      {
        // We don't want to indent prologues/epilogues.
        //
        ind_filter ind (ctx->os);

        switch (db)
        {
        case database::common:
          {
            inline_::generate ();
            break;
          }
        case database::mssql:
        case database::mysql:
        case database::oracle:
        case database::pgsql:
        case database::sqlite:
          {
            if (md == multi_database::disabled)
              inline_::generate ();

            relational::inline_::generate ();
            break;
          }
        }
      }

      // Copy epilogue.
      //
      {
        bool e (ops.ixx_epilogue ().count (db) != 0);
        bool ef (ops.ixx_epilogue_file ().count (db) != 0);

        if (e || ef)
        {
          ixx << "// Begin epilogue." << endl
              << "//" << endl;
          if (e)
            append (ixx, ops.ixx_epilogue ()[db]);
          if (ef)
            append (ixx, ops.ixx_epilogue_file ()[db]);
          ixx << "//" << endl
              << "// End epilogue." << endl
              << endl;
        }
      }

      if (ops.show_sloc ())
        cerr << ixx_name << ": " << sloc.stream ().count () << endl;

      sloc_total += sloc.stream ().count ();
    }

    // CXX
    //
    if (gen_cxx && (db != database::common || md == multi_database::dynamic))
    {
      auto_ptr<context> ctx (
        create_context (cxx, unit, ops, fts, model.get ()));

      sloc_filter sloc (ctx->os);

      cxx << "#include <odb/pre.hxx>" << endl
          << endl;

      // Copy prologue.
      //
      {
        bool p (ops.cxx_prologue ().count (db) != 0);
        bool pf (ops.cxx_prologue_file ().count (db) != 0);

        if (p || pf)
        {
          cxx << "// Begin prologue." << endl
              << "//" << endl;
          if (p)
            append (cxx, ops.cxx_prologue ()[db]);
          if (pf)
            append (cxx, ops.cxx_prologue_file ()[db]);
          cxx << "//" << endl
              << "// End prologue." << endl
              << endl;
        }
      }

      // Include query columns implementations for explicit instantiations.
      //
      string impl_guard;
      if (md == multi_database::dynamic && ctx->ext.empty ())
      {
        impl_guard = ctx->make_guard (
          "ODB_" + db.string () + "_QUERY_COLUMNS_DEF");

        cxx << "#define " << impl_guard << endl;
      }

      cxx << "#include " << ctx->process_include_path (hxx_name) << endl;

      if (!impl_guard.empty ())
        cxx << "#undef " << impl_guard << endl;

      cxx << endl;

      {
        // We don't want to indent prologues/epilogues.
        //
        ind_filter ind (ctx->os);

        // There are no -odb.hxx includes if we are generating code for
        // everything.
        //
        if (!ops.at_once ())
          include::generate (false);

        switch (db)
        {
        case database::common:
          {
            // Dynamic multi-database support.
            //
            source::generate ();
            break;
          }
        case database::mssql:
        case database::mysql:
        case database::oracle:
        case database::pgsql:
        case database::sqlite:
          {
            relational::source::generate ();
            break;
          }
        }
      }

      // Copy epilogue.
      //
      {
        bool e (ops.cxx_epilogue ().count (db) != 0);
        bool ef (ops.cxx_epilogue_file ().count (db) != 0);

        if (e || ef)
        {
          cxx << "// Begin epilogue." << endl
              << "//" << endl;
          if (e)
            append (cxx, ops.cxx_epilogue ()[db]);
          if (ef)
            append (cxx, ops.cxx_epilogue_file ()[db]);
          cxx << "//" << endl
              << "// End epilogue." << endl
              << endl;
        }
      }

      cxx << "#include <odb/post.hxx>" << endl;

      if (ops.show_sloc ())
        cerr << cxx_name << ": " << sloc.stream ().count () << endl;

      sloc_total += sloc.stream ().count ();
    }

    // SCH
    //
    if (gen_sep_schema)
    {
      auto_ptr<context> ctx (
        create_context (sch, unit, ops, fts, model.get ()));

      sloc_filter sloc (ctx->os);

      sch << "#include <odb/pre.hxx>" << endl
          << endl;

      // Copy prologue.
      //
      {
        bool p (ops.schema_prologue ().count (db) != 0);
        bool pf (ops.schema_prologue_file ().count (db) != 0);

        if (p || pf)
        {
          sch << "// Begin prologue." << endl
              << "//" << endl;
          if (p)
            append (sch, ops.schema_prologue ()[db]);
          if (pf)
            append (sch, ops.schema_prologue_file ()[db]);
          sch << "//" << endl
              << "// End prologue." << endl
              << endl;
        }
      }

      sch << "#include " << ctx->process_include_path (hxx_name) << endl
          << endl;

      {
        // We don't want to indent prologues/epilogues.
        //
        ind_filter ind (ctx->os);

        switch (db)
        {
        case database::common:
          {
            assert (false);
          }
        case database::mssql:
        case database::mysql:
        case database::oracle:
        case database::pgsql:
        case database::sqlite:
          {
            relational::schema_source::generate ();
            break;
          }
        }
      }

      // Copy epilogue.
      //
      {
        bool e (ops.schema_epilogue ().count (db) != 0);
        bool ef (ops.schema_epilogue_file ().count (db) != 0);

        if (e || ef)
        {
          sch << "// Begin epilogue." << endl
              << "//" << endl;
          if (e)
            append (sch, ops.schema_epilogue ()[db]);
          if (ef)
            append (sch, ops.schema_epilogue_file ()[db]);
          sch << "//" << endl
              << "// End epilogue." << endl
              << endl;
        }
      }

      sch << "#include <odb/post.hxx>" << endl;

      if (ops.show_sloc ())
        cerr << sch_name << ": " << sloc.stream ().count () << endl;

      sloc_total += sloc.stream ().count ();
    }

    // SQL
    //
    if (gen_sql_schema)
    {
      auto_ptr<context> ctx (
        create_context (sql, unit, ops, fts, model.get ()));

      switch (db)
      {
      case database::common:
        {
          assert (false);
        }
      case database::mssql:
      case database::mysql:
      case database::oracle:
      case database::pgsql:
      case database::sqlite:
        {
          relational::schema::generate_prologue ();

          // Copy prologue.
          //
          {
            bool p (ops.sql_prologue ().count (db) != 0);
            bool pf (ops.sql_prologue_file ().count (db) != 0);

            if (p || pf)
            {
              sql << "/* Begin prologue." << endl
                  << " */" << endl;
              if (p)
                append (sql, ops.sql_prologue ()[db]);
              if (pf)
                append (sql, ops.sql_prologue_file ()[db]);
              sql << "/*" << endl
                  << " * End prologue. */" << endl
                  << endl;
            }
          }

          if (!ops.omit_drop ())
            relational::schema::generate_drop ();

          // Copy interlude.
          //
          {
            bool i (ops.sql_interlude ().count (db) != 0);
            bool ifl (ops.sql_interlude_file ().count (db) != 0);

            if (i || ifl)
            {
              sql << "/* Begin interlude." << endl
                  << " */" << endl;
              if (i)
                append (sql, ops.sql_interlude ()[db]);
              if (ifl)
                append (sql, ops.sql_interlude_file ()[db]);
              sql << "/*" << endl
                  << " * End interlude. */" << endl
                  << endl;
            }
          }

          if (!ops.omit_create ())
            relational::schema::generate_create ();

          // Copy epilogue.
          //
          {
            bool e (ops.sql_epilogue ().count (db) != 0);
            bool ef (ops.sql_epilogue_file ().count (db) != 0);

            if (e || ef)
            {
              sql << "/* Begin epilogue." << endl
                  << " */" << endl;
              if (e)
                append (sql, ops.sql_epilogue ()[db]);
              if (ef)
                append (sql, ops.sql_epilogue_file ()[db]);
              sql << "/*" << endl
                  << " * End epilogue. */" << endl
                  << endl;
            }
          }

          relational::schema::generate_epilogue ();
          break;
        }
      }
    }

    // Save the changelog if it changed.
    //
    if (gen_log)
    {
      try
      {
        ostringstream os;
        os.exceptions (ifstream::badbit | ifstream::failbit);
        xml::serializer s (os, out_log_path.string ());
        changelog->serialize (s);
        string const& changelog_xml (os.str ());

        if (changelog_xml != old_changelog_xml)
        {
          ofstream log (out_log_path.string ().c_str (),
                        ios_base::out | ios_base::binary);

          if (!log.is_open ())
          {
            cerr << "error: unable to open '" << out_log_path << "' in " <<
              "write mode" << endl;
            throw failed ();
          }

          if (old_changelog == 0)
            auto_rm.add (out_log_path);

          log.exceptions (ifstream::badbit | ifstream::failbit);
          log << changelog_xml;
        }
      }
      catch (const ios_base::failure& e)
      {
        cerr << out_log_path << ": write failure" << endl;
        throw failed ();
      }
      catch (const xml::serialization& e)
      {
        cerr << e.what () << endl;
        throw failed ();
      }
    }

    // Communicate the sloc count to the driver. This is necessary to
    // correctly handle the total if we are compiling multiple files in
    // one invocation.
    //
    if (ops.show_sloc () || ops.sloc_limit_specified ())
      cout << "odb:sloc:" << sloc_total << endl;

    auto_rm.cancel ();
  }
  catch (operation_failed const&)
  {
    // Code generation failed. Diagnostics has already been issued.
    //
    throw failed ();
  }
  catch (semantics::invalid_path const& e)
  {
    cerr << "error: '" << e.path () << "' is not a valid filesystem path"
         << endl;
    throw failed ();
  }
  catch (fs::error const&)
  {
    // Auto-removal of generated files failed. Ignore it.
    //
    throw failed ();
  }
}