//
// Tests that merging chunks via mongos works/doesn't work with different chunk configurations
// with a compound shard key.
//

import {ShardingTest} from "jstests/libs/shardingtest.js";

var getShardVersion = function() {
    var res = st.shard0.adminCommand({getShardVersion: coll + ""});
    assert.commandWorked(res);
    var version = res.global;
    assert(version);
    return version;
};

// Merge two neighboring chunks and check post conditions.
var checkMergeWorked = function(lowerBound, upperBound) {
    var oldVersion = getShardVersion();
    var numChunksBefore = chunks.find().itcount();

    assert.commandWorked(
        admin.runCommand({mergeChunks: coll + "", bounds: [lowerBound, upperBound]}));

    assert.eq(numChunksBefore - 1, chunks.find().itcount());
    assert.eq(1, chunks.find({min: lowerBound, max: upperBound}).itcount());

    var newVersion = getShardVersion();
    assert.eq(newVersion.t, oldVersion.t);
    assert.gt(newVersion.i, oldVersion.i);
};

var st = new ShardingTest({shards: 2, mongos: 1});

var mongos = st.s;
var admin = mongos.getDB("admin");
var shards = mongos.getCollection("config.shards").find().toArray();
var chunks = mongos.getCollection("config.chunks");
var coll = mongos.getCollection("foo.bar");

jsTest.log("Create a sharded collection with a compound shard key.");
assert.commandWorked(
    admin.runCommand({enableSharding: coll.getDB() + "", primaryShard: st.shard0.shardName}));
assert.commandWorked(admin.runCommand({shardCollection: coll + "", key: {x: 1, y: 1}}));

// Chunks after splits:
// (MinKey, { x: 0, y: 1 })
// ({ x: 0, y: 1 }, { x: 1, y: 0 })
// ({ x: 1, y: 0 }, { x: 2, y: 0 })
// ({ x: 2, y: 0 }, { x: 2, y: 1 })
// ({ x: 2, y: 1 }, MaxKey)
jsTest.log("Create chunks.");
assert.commandWorked(admin.runCommand({split: coll + "", middle: {x: 0, y: 1}}));
assert.commandWorked(admin.runCommand({split: coll + "", middle: {x: 1, y: 0}}));
assert.commandWorked(admin.runCommand({split: coll + "", middle: {x: 2, y: 0}}));
assert.commandWorked(admin.runCommand({split: coll + "", middle: {x: 2, y: 1}}));

jsTest.log("Insert some data into each of the chunk ranges.");
assert.commandWorked(coll.insert({x: -1, y: 2}));
assert.commandWorked(coll.insert({x: 0, y: 2}));
assert.commandWorked(coll.insert({x: 1, y: 2}));
assert.commandWorked(coll.insert({x: 2, y: 1}));
assert.commandWorked(coll.insert({x: 2, y: 3}));

// Chunks after merge:
// (MinKey, { x: 0, y: 1 })
// ({ x: 0, y: 1 }, { x: 2, y: 0 })
// ({ x: 2, y: 0 }, { x: 2, y: 1 })
// ({ x: 2, y: 1 }, MaxKey)
jsTest.log("Merge chunks whose upper and lower bounds are compound shard keys.");
checkMergeWorked({x: 0, y: 1}, {x: 2, y: 0});

// Chunks after merge:
// (MinKey, { x: 2, y: 0 })
// ({ x: 2, y: 0 }, { x: 2, y: 1 })
// ({ x: 2, y: 1 }, MaxKey)
jsTest.log("Merge chunks whose upper bound contains a compound shard key, lower bound is MinKey");
checkMergeWorked({x: MinKey, y: MinKey}, {x: 2, y: 0});

// Chunks after merge:
// (MinKey, { x: 2, y: 0 })
// ({ x: 2, y: 0 }, MaxKey)
jsTest.log("Merge chunks whose lower bound contains a compound shard key, upper bound is MaxKey");
checkMergeWorked({x: 2, y: 0}, {x: MaxKey, y: MaxKey});

// Chunks after merge:
// (MinKey, MaxKey)
jsTest.log("Merge chunks whos bounds are MinKey/MaxKey, but which have a compound shard key");
checkMergeWorked({x: MinKey, y: MinKey}, {x: MaxKey, y: MaxKey});

st.stop();