// Tests that the sort specification is obeyed when the query contains $near/$nearSphere.
(function() {
    'use strict';

    const st = new ShardingTest({shards: 2});
    const db = st.getDB("test");
    const coll = db.geo_near_sort;
    const caseInsensitive = {locale: "en_US", strength: 2};

    assert.commandWorked(st.s0.adminCommand({enableSharding: db.getName()}));
    st.ensurePrimaryShard(db.getName(), st.shard0.shardName);
    assert.commandWorked(st.s0.adminCommand({shardCollection: coll.getFullName(), key: {_id: 1}}));

    // Split the data into 2 chunks and move the chunk with _id > 0 to shard 1.
    assert.commandWorked(st.s0.adminCommand({split: coll.getFullName(), middle: {_id: 0}}));
    assert.commandWorked(st.s0.adminCommand(
        {movechunk: coll.getFullName(), find: {_id: 1}, to: st.shard1.shardName}));

    // Insert some documents. The sort order by distance from the origin is [-2, 1, -1, 2] (under 2d
    // or 2dsphere geometry). The sort order by {a: 1} under the case-insensitive collation is [2,
    // -1, 1, -2]. The sort order by {b: 1} is [2. -1, 1, -2].
    const docMinus2 = {_id: -2, geo: [0, 0], a: "BB", b: 3};
    const docMinus1 = {_id: -1, geo: [0, 2], a: "aB", b: 1};
    const doc1 = {_id: 1, geo: [0, 1], a: "Ba", b: 2};
    const doc2 = {_id: 2, geo: [0, 3], a: "aa", b: 0};
    assert.writeOK(coll.insert(docMinus2));
    assert.writeOK(coll.insert(docMinus1));
    assert.writeOK(coll.insert(doc1));
    assert.writeOK(coll.insert(doc2));

    function testSortOrders(query, indexSpec) {
        assert.commandWorked(coll.createIndex(indexSpec));

        // Test a $near/$nearSphere query without a specified sort. The results should be sorted by
        // distance from the origin.
        let res = coll.find(query).toArray();
        assert.eq(res.length, 4, tojson(res));
        assert.eq(res[0], docMinus2, tojson(res));
        assert.eq(res[1], doc1, tojson(res));
        assert.eq(res[2], docMinus1, tojson(res));
        assert.eq(res[3], doc2, tojson(res));

        // Test with a limit.
        res = coll.find(query).limit(2).toArray();
        assert.eq(res.length, 2, tojson(res));
        assert.eq(res[0], docMinus2, tojson(res));
        assert.eq(res[1], doc1, tojson(res));

        if (db.getMongo().useReadCommands()) {
            // Test a $near/$nearSphere query sorted by {a: 1} with the case-insensitive collation.
            res = coll.find(query).collation(caseInsensitive).sort({a: 1}).toArray();
            assert.eq(res.length, 4, tojson(res));
            assert.eq(res[0], doc2, tojson(res));
            assert.eq(res[1], docMinus1, tojson(res));
            assert.eq(res[2], doc1, tojson(res));
            assert.eq(res[3], docMinus2, tojson(res));

            // Test with a limit.
            res = coll.find(query).collation(caseInsensitive).sort({a: 1}).limit(2).toArray();
            assert.eq(res.length, 2, tojson(res));
            assert.eq(res[0], doc2, tojson(res));
            assert.eq(res[1], docMinus1, tojson(res));
        }

        // Test a $near/$nearSphere query sorted by {b: 1}.
        res = coll.find(query).sort({b: 1}).toArray();
        assert.eq(res.length, 4, tojson(res));
        assert.eq(res[0], doc2, tojson(res));
        assert.eq(res[1], docMinus1, tojson(res));
        assert.eq(res[2], doc1, tojson(res));
        assert.eq(res[3], docMinus2, tojson(res));

        // Test with a limit.
        res = coll.find(query).sort({b: 1}).limit(2).toArray();
        assert.eq(res.length, 2, tojson(res));
        assert.eq(res[0], doc2, tojson(res));
        assert.eq(res[1], docMinus1, tojson(res));

        assert.commandWorked(coll.dropIndex(indexSpec));
    }

    testSortOrders({geo: {$near: [0, 0]}}, {geo: "2d"});
    testSortOrders({geo: {$nearSphere: [0, 0]}}, {geo: "2d"});
    testSortOrders({geo: {$near: {$geometry: {type: "Point", coordinates: [0, 0]}}}},
                   {geo: "2dsphere"});
    testSortOrders({geo: {$nearSphere: {$geometry: {type: "Point", coordinates: [0, 0]}}}},
                   {geo: "2dsphere"});

    st.stop();
})();