/**
 * Repeatedly creates and drops a sharded time-series collection.
 *
 * @tags: [
 *   requires_sharding,
 *   does_not_support_stepdowns,
 *   does_not_support_transactions,
 *   requires_fcv_51,
 * ]
 */
'use strict';

const dbPrefix = 'fsm_db_for_sharded_timeseries_collection_';
const dbCount = 2;
const collPrefix = 'sharded_timeseries_collection_';
const collCount = 2;
const timeField = 'time';
const metaField = 'hostId';

load("jstests/core/timeseries/libs/timeseries.js");  // For 'TimeseriesTest' helpers.

function getRandomDb(db) {
    return db.getSiblingDB(dbPrefix + Random.randInt(dbCount));
}

function getRandomTimeseriesView(db) {
    return getRandomDb(db)[collPrefix + Random.randInt(collCount)];
}

var $config = (function() {
    const setup = function(db, collName, cluster) {
        // Check that necessary feature flags are enabled on each of the mongods.
        let isEnabled = true;
        cluster.executeOnMongodNodes(function(db) {
            if (!TimeseriesTest.shardedtimeseriesCollectionsEnabled(db)) {
                isEnabled = false;
            }
        });
        this.isShardedTimeseriesEnabled = isEnabled;

        if (!this.isShardedTimeseriesEnabled) {
            jsTestLog(
                "Feature flags for sharded time-series collections are not enabled. This test will do nothing.");
            return;
        }

        // Enable sharding for the test databases.
        for (var i = 0; i < dbCount; i++) {
            const dbName = dbPrefix + i;
            db.adminCommand({enablesharding: dbName});
        }
    };

    const states = {
        init: function(db, collName) {},
        create: function(db, collName) {
            if (!this.isShardedTimeseriesEnabled) {
                return;
            }

            const coll = getRandomTimeseriesView(db);
            jsTestLog("Executing create state on: " + coll.getFullName());
            assertAlways.commandWorked(db.adminCommand({
                shardCollection: coll.getFullName(),
                key: {[metaField]: 1, [timeField]: 1},
                timeseries: {timeField: timeField, metaField: metaField}
            }));
        },
        dropView: function(db, collName) {
            if (!this.isShardedTimeseriesEnabled) {
                return;
            }

            const coll = getRandomTimeseriesView(db);
            jsTestLog("Executing dropView state on: " + coll.getFullName());
            assertAlways.commandWorked(coll.getDB().runCommand({drop: coll.getName()}));
        },
    };

    const transitions = {
        init: {create: 0.33, dropView: 0.33},
        create: {create: 0.33, dropView: 0.33},
        dropView: {create: 0.33, dropView: 0.33},
    };

    return {
        threadCount: 12,
        iterations: 64,
        startState: 'init',
        data: {},
        states: states,
        setup: setup,
        transitions: transitions
    };
})();