'use strict';

/**
 * explain_find.js
 *
 * Runs explain() and find() on a collection.
 *
 */
load('jstests/concurrency/fsm_libs/extend_workload.js');  // for extendWorkload
load('jstests/concurrency/fsm_workloads/explain.js');     // for $config
load('jstests/libs/analyze_plan.js');                     // for planHasStage and isIxscan

var $config = extendWorkload(
    $config,
    function($config, $super) {

        $config.states = Object.extend(
            {
              explainLimit: function explainLimit(db, collName) {
                  var res = db[collName].find().limit(3).explain();
                  assertAlways.commandWorked(res);
                  assertAlways(planHasStage(res.queryPlanner.winningPlan, 'LIMIT'));
              },
              explainBatchSize: function explainBatchSize(db, collName) {
                  var res = db[collName].find().batchSize(3).explain();
                  assertAlways.commandWorked(res);
              },
              explainAddOption: function explainAddOption(db, collName) {
                  var res =
                      db[collName].explain().find().addOption(DBQuery.Option.exhaust).finish();
                  assertAlways.commandWorked(res);
              },
              explainSkip: function explainSkip(db, collName) {
                  var res = db[collName].explain().find().skip(3).finish();
                  assertAlways.commandWorked(res);
                  assertAlways(planHasStage(res.queryPlanner.winningPlan, 'SKIP'));
              },
              explainSort: function explainSort(db, collName) {
                  var res = db[collName].find().sort({i: -1}).explain();
                  assertAlways.commandWorked(res);
                  assertAlways(planHasStage(res.queryPlanner.winningPlan, 'SORT'));
              },
              explainHint: function explainHint(db, collName) {
                  assertWhenOwnColl(function() {
                      var res = db[collName].find().hint({j: 1}).explain();
                      assertWhenOwnColl.commandWorked(res);
                      assertWhenOwnColl(isIxscan(res.queryPlanner.winningPlan));
                  });
              },
              explainMaxTimeMS: function explainMaxTimeMS(db, collName) {
                  var res = db[collName].find().maxTimeMS(2000).explain();
                  assertAlways.commandWorked(res);
              },
              explainSnapshot: function explainSnapshot(db, collName) {
                  var res = db[collName].find().snapshot().explain();
                  assertAlways.commandWorked(res);
                  assertWhenOwnColl(isIxscan(res.queryPlanner.winningPlan));
              }
            },
            $super.states);

        $config.transitions =
            Object.extend({explain: $config.data.assignEqualProbsToTransitions($config.states)},
                          $super.transitions);

        // doubling number of iterations so there is a higher chance we will
        // transition to each of the 8 new states at least once
        $config.iterations = $super.iterations * 2;

        return $config;
    });