// file      : build2/test/init.cxx -*- C++ -*-
// copyright : Copyright (c) 2014-2019 Code Synthesis Ltd
// license   : MIT; see accompanying LICENSE file

#include <build2/test/init.hxx>

#include <libbuild2/scope.hxx>
#include <libbuild2/target.hxx>
#include <libbuild2/rule.hxx>
#include <libbuild2/diagnostics.hxx>

#include <build2/config/utility.hxx>

#include <build2/test/module.hxx>
#include <build2/test/target.hxx>
#include <build2/test/operation.hxx>

using namespace std;
using namespace butl;

namespace build2
{
  namespace test
  {
    bool
    boot (scope& rs, const location&, unique_ptr<module_base>& mod)
    {
      tracer trace ("test::boot");

      l5 ([&]{trace << "for " << rs;});

      // Register our operations.
      //
      rs.insert_operation (test_id, op_test);
      rs.insert_operation (update_for_test_id, op_update_for_test);

      // Enter module variables. Do it during boot in case they get assigned
      // in bootstrap.build.
      //
      auto& vp (var_pool.rw (rs));

      common_data d {

        // Tests to execute.
        //
        // Specified as <target>@<path-id> pairs with both sides being
        // optional. The variable is untyped (we want a list of name-pairs),
        // overridable, and inheritable. The target is relative (in essence a
        // prerequisite) which is resolved from the (root) scope where the
        // config.test value is defined.
        //
        vp.insert ("config.test", true),

        // Test working directory before/after cleanup (see Testscript spec
        // for semantics).
        //
        vp.insert<name_pair> ("config.test.output", true),

        // The test variable is a name which can be a path (with the
        // true/false special values) or a target name.
        //
        // Note: none are overridable.
        //
        vp.insert<name>    ("test",           variable_visibility::target),
        vp.insert<strings> ("test.options",   variable_visibility::project),
        vp.insert<strings> ("test.arguments", variable_visibility::project),

        // Prerequisite-specific.
        //
        // test.stdin and test.stdout can be used to mark a prerequisite as a
        // file to redirect stdin from and to compare stdout to, respectively.
        // test.roundtrip is a shortcut to mark a prerequisite as both stdin
        // and stdout.
        //
        // Prerequisites marked with test.input are treated as additional test
        // inputs: they are made sure to be up to date and their paths are
        // passed as additional command line arguments (after test.options and
        // test.arguments). Their primary use is to pass inputs that may have
        // varying file names/paths, for example:
        //
        // exe{parent}: exe{child}: test.input = true
        //
        // Note that currently this mechanism is only available to simple
        // tests though we could also support it for testscript (e.g., by
        // appending the input paths to test.arguments or by passing them in a
        // separate test.inputs variable).
        //
        vp.insert<bool> ("test.stdin",     variable_visibility::prereq),
        vp.insert<bool> ("test.stdout",    variable_visibility::prereq),
        vp.insert<bool> ("test.roundtrip", variable_visibility::prereq),
        vp.insert<bool> ("test.input",     variable_visibility::prereq),

        // Test target platform.
        //
        vp.insert<target_triplet> ("test.target", variable_visibility::project)
      };

      // These are only used in testscript.
      //
      vp.insert<strings> ("test.redirects", variable_visibility::project);
      vp.insert<strings> ("test.cleanups",  variable_visibility::project);

      // Unless already set, default test.target to build.host. Note that it
      // can still be overriden by the user, e.g., in root.build.
      //
      {
        value& v (rs.assign (d.test_target));

        if (!v || v.empty ())
          v = cast<target_triplet> ((*global_scope)["build.host"]);
      }

      mod.reset (new module (move (d)));
      return false;
    }

    bool
    init (scope& rs,
          scope&,
          const location& l,
          unique_ptr<module_base>& mod,
          bool first,
          bool,
          const variable_map& config_hints)
    {
      tracer trace ("test::init");

      if (!first)
      {
        warn (l) << "multiple test module initializations";
        return true;
      }

      const dir_path& out_root (rs.out_path ());
      l5 ([&]{trace << "for " << out_root;});

      assert (mod != nullptr);
      module& m (static_cast<module&> (*mod));

      // Configure.
      //
      assert (config_hints.empty ()); // We don't known any hints.

      // Adjust module priority so that the config.test.* values are saved at
      // the end of config.build.
      //
      config::save_module (rs, "test", INT32_MAX);

      // config.test
      //
      if (lookup l = config::omitted (rs, m.config_test).first)
      {
        // Figure out which root scope it came from.
        //
        scope* s (&rs);
        for (;
             s != nullptr && !l.belongs (*s);
             s = s->parent_scope ()->root_scope ())
        assert (s != nullptr);

        m.test_ = &cast<names> (l);
        m.root_ = s;
      }

      // config.test.output
      //
      if (lookup l = config::omitted (rs, m.config_test_output).first)
      {
        const name_pair& p (cast<name_pair> (l));

        // If second half is empty, then first is the after value.
        //
        const name& a (p.second.empty () ? p.first  : p.second); // after
        const name& b (p.second.empty () ? p.second : p.first);  // before

        // Parse and validate.
        //
        if (!b.simple ())
          fail << "invalid config.test.output before value '" << b << "'";

        if (!a.simple ())
          fail << "invalid config.test.output after value '" << a << "'";

        if      (a.value == "clean") m.after = output_after::clean;
        else if (a.value == "keep")  m.after = output_after::keep;
        else fail << "invalid config.test.output after value '" << a << "'";

        if      (b.value == "fail")  m.before = output_before::fail;
        else if (b.value == "warn")  m.before = output_before::warn;
        else if (b.value == "clean") m.before = output_before::clean;
        else if (b.value == "")      m.before = output_before::clean;
        else fail << "invalid config.test.output before value '" << b << "'";
      }

      //@@ TODO: Need ability to specify extra diff options (e.g.,
      //   --strip-trailing-cr, now hardcoded).
      //
      //@@ TODO: Pring report.

      // Register target types.
      //
      {
        auto& t (rs.target_types);

        auto& tt (t.insert<testscript> ());
        t.insert_file ("testscript", tt);
      }

      // Register our test running rule.
      //
      {
        default_rule& dr (m);

        rs.rules.insert<target> (perform_test_id, "test", dr);
        rs.rules.insert<alias>  (perform_test_id, "test", dr);
      }

      return true;
    }
  }
}