// Tests whether the noBalance flag disables balancing for collections

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

// First, test that shell helpers require an argument
assert.throws(sh.disableBalancing, [], "sh.disableBalancing requires a collection");
assert.throws(sh.enableBalancing, [], "sh.enableBalancing requires a collection");


// Initially stop balancing
st.stopBalancer()

var shardAName = st._shardNames[0]
var shardBName = st._shardNames[1]

var collA = st.s.getCollection( jsTest.name() + ".collA" )
var collB = st.s.getCollection( jsTest.name() + ".collB" )

// Shard two collections
st.shardColl( collA, { _id : 1 }, false )
st.shardColl( collB, { _id : 1 }, false )

// Split into a lot of chunks so balancing can occur
for( var i = 0; i < 10 - 1; i++ ){ // 10 chunks total
    collA.getMongo().getDB("admin").runCommand({ split : collA + "", middle : { _id : i } })
    collA.getMongo().getDB("admin").runCommand({ split : collB + "", middle : { _id : i } })
}

// Disable balancing on one collection
sh.disableBalancing( collB )

jsTest.log( "Balancing disabled on " + collB )
printjson( collA.getDB().getSisterDB( "config" ).collections.find().toArray() )

st.startBalancer()

// Make sure collA gets balanced
assert.soon( function(){
    var shardAChunks = st.s.getDB( "config" ).chunks.find({ _id : sh._collRE( collA ), shard : shardAName }).itcount()
    var shardBChunks = st.s.getDB( "config" ).chunks.find({ _id : sh._collRE( collA ), shard : shardBName }).itcount()
    printjson({ shardA : shardAChunks, shardB : shardBChunks })
    return shardAChunks == shardBChunks
}, "" + collA + " chunks not balanced!", 5 * 60 * 1000 )

jsTest.log( "Chunks for " + collA + " are balanced." )

// Check that the collB chunks were not moved
var shardAChunks = st.s.getDB( "config" ).chunks.find({ _id : sh._collRE( collB ), shard : shardAName }).itcount()
var shardBChunks = st.s.getDB( "config" ).chunks.find({ _id : sh._collRE( collB ), shard : shardBName }).itcount()
printjson({ shardA : shardAChunks, shardB : shardBChunks })
assert( shardAChunks == 0 || shardBChunks == 0 )

// Re-enable balancing for collB
sh.enableBalancing( collB )

// Make sure that collB is now balanced
assert.soon( function(){
    var shardAChunks = st.s.getDB( "config" ).chunks.find({ _id : sh._collRE( collB ), shard : shardAName }).itcount()
    var shardBChunks = st.s.getDB( "config" ).chunks.find({ _id : sh._collRE( collB ), shard : shardBName }).itcount()
    printjson({ shardA : shardAChunks, shardB : shardBChunks })
    return shardAChunks == shardBChunks
}, "" + collB + " chunks not balanced!", 5 * 60 * 1000 )

jsTest.log( "Chunks for " + collB + " are balanced." )

// Re-disable balancing for collB
sh.disableBalancing( collB )
// Wait for the balancer to fully finish the last migration and write the changelog
// MUST set db var here, ugly but necessary
db = st.s0.getDB("config")
sh.waitForBalancer(true)

// Make sure auto-migrates on insert don't move chunks
var lastMigration = sh._lastMigration( collB )

var bulk = collB.initializeUnorderedBulkOp();
for( var i = 0; i < 1000000; i++ ){
    bulk.insert({ _id: i, hello: "world" });
}
assert.writeOK(bulk.execute());

printjson( lastMigration )
printjson( sh._lastMigration( collB ) )

if( lastMigration == null ) assert.eq( null, sh._lastMigration( collB ) )
else assert.eq( lastMigration.time, sh._lastMigration( collB ).time )

st.stop()