// When a migration is in progress from shard0 to shard1 on coll1, shard2 is unable to start a
// migration with either shard in the following cases:
//     1. coll2 shard0 to shard2 -- shard0 can't send two chunks simultaneously.
//     2. coll2 shard2 to shard1 -- shard1 can't receive two chunks simultaneously.

load('jstests/libs/chunk_manipulation_util.js');

(function() {
"use strict";

var staticMongod = MongoRunner.runMongod({});  // For startParallelOps.

var st = new ShardingTest({shards: 3});

var mongos = st.s0, admin = mongos.getDB('admin'), dbName = "testDB", ns1 = dbName + ".foo",
    coll1 = mongos.getCollection(ns1), shard0 = st.shard0, shard1 = st.shard1, shard2 = st.shard2,
    shard0Coll1 = shard0.getCollection(ns1), shard1Coll1 = shard1.getCollection(ns1),
    shard2Coll1 = shard2.getCollection(ns1);

assert.commandWorked(admin.runCommand({enableSharding: dbName}));
st.ensurePrimaryShard(dbName, st.shard0.shardName);

assert.commandWorked(admin.runCommand({shardCollection: ns1, key: {a: 1}}));
assert.commandWorked(admin.runCommand({split: ns1, middle: {a: 0}}));
assert.commandWorked(admin.runCommand({split: ns1, middle: {a: 10}}));
assert.commandWorked(coll1.insert({a: -10}));
assert.commandWorked(coll1.insert({a: 0}));
assert.commandWorked(coll1.insert({a: 10}));
assert.eq(3, shard0Coll1.find().itcount());
assert.eq(0, shard1Coll1.find().itcount());
assert.eq(0, shard2Coll1.find().itcount());
assert.eq(3, coll1.find().itcount());

assert.commandWorked(admin.runCommand(
    {moveChunk: ns1, find: {a: 10}, to: st.shard2.shardName, _waitForDelete: true}));

// Shard0:
//      coll1:     [-inf, 0) [0, 10)
// Shard1:
// Shard2:
//      coll1:     [10, +inf)

jsTest.log("Set up complete, now proceeding to test that migration interruptions fail.");

// Start a migration between shard0 and shard1 on coll1 and then pause it
pauseMigrateAtStep(shard1, migrateStepNames.rangeDeletionTaskScheduled);
var joinMoveChunk = moveChunkParallel(staticMongod,
                                      st.s0.host,
                                      {a: 0},
                                      null,
                                      coll1.getFullName(),
                                      st.shard1.shardName,
                                      true /**Parallel should expect success */);
waitForMigrateStep(shard1, migrateStepNames.rangeDeletionTaskScheduled);

assert.commandFailedWithCode(
    admin.runCommand({moveChunk: ns1, find: {a: -10}, to: st.shard2.shardName}),
    ErrorCodes.ConflictingOperationInProgress,
    "(1) A shard should not be able to be the donor for two ongoing migrations.");

assert.commandFailedWithCode(
    admin.runCommand({moveChunk: ns1, find: {a: 10}, to: st.shard1.shardName}),
    ErrorCodes.ConflictingOperationInProgress,
    "(2) A shard should not be able to be the recipient of two ongoing migrations.");

assert.commandFailedWithCode(
    admin.runCommand({moveChunk: ns1, find: {a: 10}, to: st.shard0.shardName}),
    ErrorCodes.ConflictingOperationInProgress,
    "(3) A shard should not be able to be both a donor and recipient of migrations.");

// Finish migration
unpauseMigrateAtStep(shard1, migrateStepNames.rangeDeletionTaskScheduled);
joinMoveChunk();
assert.eq(1, shard0Coll1.find().itcount());
assert.eq(1, shard1Coll1.find().itcount());
assert.eq(1, shard2Coll1.find().itcount());

st.stop();
MongoRunner.stopMongod(staticMongod);
})();