//
// Tests whether the fromMigrate flag is correctly set during migrations.
//
// Tests:
//      #1 (delete op) fromMigrate is set when recipient shard deletes all documents locally
//         in the chunk range it is about to receive from the donor shard.
//      #2 (delete op) fromMigrate is set when the donor shard deletes documents that have
//         been migrated to another shard.
//      #3 (insert op) fromMigrate is set when the recipient shard receives chunk migration
//         data and inserts it.
//      #4 (update op) fromMigrate is set when an update occurs in the donor shard during
//         migration and is sent to the recipient via the transfer logs.
//      #5 fromMigrate is NOT set on donor shard and IS set on the recipient shard when real
//         delete op is done during chunk migration within the chunk range.
//

import {
    migrateStepNames,
    moveChunkParallel,
    pauseMigrateAtStep,
    unpauseMigrateAtStep,
    waitForMigrateStep,
} from "jstests/libs/chunk_manipulation_util.js";
import {ShardingTest} from "jstests/libs/shardingtest.js";

let staticMongod = MongoRunner.runMongod({});

let st = new ShardingTest({shards: 2, mongos: 1, rs: {nodes: 1}});

const dbName = "testDB";
const ns = dbName + ".foo";

let mongos = st.s0;
let admin = mongos.getDB("admin");
let coll = mongos.getCollection(ns);

let donor = st.shard0;
let recipient = st.shard1;
let donorColl = donor.getCollection(ns);
let recipientColl = recipient.getCollection(ns);
let donorLocal = donor.getDB("local");
let recipientLocal = recipient.getDB("local");

// Two chunks
// Donor:     [0, 2) [2, 5)
// Recipient:
jsTest.log("Enable sharding of the collection and split into two chunks....");

assert.commandWorked(admin.runCommand({enableSharding: dbName, primaryShard: st.shard0.shardName}));
assert.commandWorked(admin.runCommand({shardCollection: ns, key: {_id: 1}}));
assert.commandWorked(admin.runCommand({split: ns, middle: {_id: 2}}));

// 6 documents,
//        donor: 2 in the first chunk, 3 in the second.
//    recipient: 1 document (shardkey overlaps with a doc in second chunk of donor shard)
jsTest.log("Inserting 5 docs into donor shard, ensuring one orphan on the recipient shard....");

// Insert just one document into the collection and fail a migration after the cloning step in
// order to get an orphan onto the recipient shard with the correct UUID for the collection.
assert.commandWorked(coll.insert({_id: 2}));
assert.eq(1, donorColl.count());
assert.commandWorked(recipient.adminCommand({configureFailPoint: "failMigrationOnRecipient", mode: "alwaysOn"}));
assert.commandFailed(admin.runCommand({moveChunk: coll.getFullName(), find: {_id: 2}, to: st.shard1.shardName}));
assert.commandWorked(recipient.adminCommand({configureFailPoint: "failMigrationOnRecipient", mode: "off"}));

// Insert the remaining documents into the collection.
assert.commandWorked(coll.insert({_id: 0}));
assert.commandWorked(coll.insert({_id: 1}));
assert.commandWorked(coll.insert({_id: 3}));
assert.commandWorked(coll.insert({_id: 4}));
assert.eq(5, donorColl.count());

/**
 * Set failpoint: recipient will pause migration after cloning chunk data from donor,
 * before checking transfer mods log on donor.
 */

jsTest.log("setting recipient failpoint cloned");
pauseMigrateAtStep(recipient, migrateStepNames.cloned);

/**
 * Start moving chunk [2, 5) from donor shard to recipient shard, run in the background.
 */

// Donor:     [0, 2)
// Recipient:    [2, 5)
jsTest.log("Starting chunk migration, pause after cloning...");

let joinMoveChunk = moveChunkParallel(
    staticMongod,
    st.s0.host,
    {_id: 2},
    null,
    coll.getFullName(),
    st.shard1.shardName,
);

/**
 * Wait for recipient to finish cloning.
 * THEN update 1 document {_id: 3} on donor within the currently migrating chunk.
 * AND delete 1 document {_id: 4} on donor within the currently migrating chunk.
 */

waitForMigrateStep(recipient, migrateStepNames.cloned);

jsTest.log("Update 1 doc and delete 1 doc on donor within the currently migrating chunk...");

assert.commandWorked(coll.update({_id: 3}, {_id: 3, a: "updated doc"}));
assert.commandWorked(coll.remove({_id: 4}));

/**
 * Finish migration. Unpause recipient migration, wait for it to collect
 * the transfer mods log from donor and finish migration.
 */

jsTest.log("Continuing and finishing migration...");
unpauseMigrateAtStep(recipient, migrateStepNames.cloned);
joinMoveChunk();

/**
 * Check documents are where they should be: 2 docs in donor chunk, 2 docs in recipient chunk
 * (because third doc in recipient shard's chunk got deleted on the donor shard during
 * migration).
 */

jsTest.log("Checking that documents are on the shards they should be...");

assert.eq(2, recipientColl.count(), "Recipient shard doesn't have exactly 2 documents!");
assert.eq(2, donorColl.count(), "Donor shard doesn't have exactly 2 documents!");
assert.eq(4, coll.count(), "Collection total is not 4!");

/**
 * Check that the fromMigrate flag has been set correctly in donor and recipient oplogs,
 */

jsTest.log("Checking donor and recipient oplogs for correct fromMigrate flags...");

function assertEqAndDumpOpLog(expected, actual, msg) {
    if (expected === actual) return;

    const oplogFilter = {$or: [{ns: ns}, {"o.applyOps.0.ns": ns}]};
    print("Dumping oplog contents for", ns);
    print("On donor:");
    print(tojson(donorLocal.oplog.rs.find(oplogFilter).toArray()));

    print("On recipient:");
    print(tojson(recipientLocal.oplog.rs.find(oplogFilter).toArray()));

    assert.eq(expected, actual, msg);
}

let donorOplogRes = donorLocal.oplog.rs.find({op: "d", fromMigrate: true, "o._id": 2}).count();
// This delete oplog entry could be wrapped in a applyOps entry if the delete was done in a batch.
if (!donorOplogRes) {
    // Validate this is a batched delete, which generates one applyOps entry instead of a 'd' entry.
    donorOplogRes = donorLocal.oplog.rs
        .find({
            ns: "admin.$cmd",
            op: "c",
            "o.applyOps": {$elemMatch: {op: "d", "o._id": 2, fromMigrate: true}},
        })
        .count();
}
assertEqAndDumpOpLog(
    1,
    donorOplogRes,
    "fromMigrate flag wasn't set on the donor shard's oplog for " + "migrating delete op on {_id: 2}! Test #2 failed.",
);

donorOplogRes = donorLocal.oplog.rs.find({op: "d", fromMigrate: {$exists: false}, "o._id": 4}).count();
if (!donorOplogRes) {
    // Validate this is a batched delete, which generates one applyOps entry instead of a 'd' entry.
    donorOplogRes = donorLocal.oplog.rs
        .find({
            ns: "admin.$cmd",
            op: "c",
            "o.applyOps": {$elemMatch: {op: "d", "o._id": 4, fromMigrate: {$exists: false}}},
        })
        .count();
}
assertEqAndDumpOpLog(
    1,
    donorOplogRes,
    "Real delete of {_id: 4} on donor shard incorrectly set the " + "fromMigrate flag in the oplog! Test #5 failed.",
);

let recipientOplogRes = recipientLocal.oplog.rs.find({op: "i", fromMigrate: true, "o._id": 2}).count();
// Expect to see one insert oplog entry for _id:2 because that doc was cloned on its own as part
// of the failed migrate.  Also expect to see one applyOps entry containing _id:2 as part of a
// batched insert from the second migrate
assertEqAndDumpOpLog(
    1,
    recipientOplogRes,
    "fromMigrate flag wasn't set on the recipient shard's " +
        "oplog for migrating insert op on {_id: 2}! Test #3 failed.",
);

// Note we expect the applyOps to have fromMigrate set, and also the operation within the
// applyOps to have fromMigrate set.
recipientOplogRes = recipientLocal.oplog.rs
    .find({
        op: "c",
        fromMigrate: true,
        "o.applyOps": {$elemMatch: {fromMigrate: true, "o._id": 2}},
    })
    .count();
assertEqAndDumpOpLog(
    1,
    recipientOplogRes,
    "fromMigrate flag wasn't set on the recipient shard's " +
        "applyOps entry for migrating insert op on {_id: 2}! Test #3 failed.",
);

recipientOplogRes = recipientLocal.oplog.rs.find({op: "d", fromMigrate: true, "o._id": 2}).count();
assertEqAndDumpOpLog(
    1,
    recipientOplogRes,
    "fromMigrate flag wasn't set on the recipient shard's " +
        "oplog for delete op on the old {_id: 2} that overlapped " +
        "with the chunk about to be copied! Test #1 failed.",
);

recipientOplogRes = recipientLocal.oplog.rs.find({op: "u", fromMigrate: true, "o._id": 3}).count();
assertEqAndDumpOpLog(
    1,
    recipientOplogRes,
    "fromMigrate flag wasn't set on the recipient shard's " + "oplog for update op on {_id: 3}! Test #4 failed.",
);

recipientOplogRes = recipientLocal.oplog.rs.find({op: "d", fromMigrate: true, "o._id": 4}).count();
assertEqAndDumpOpLog(
    1,
    recipientOplogRes,
    "fromMigrate flag wasn't set on the recipient shard's " +
        "oplog for delete op on {_id: 4} that occurred during " +
        "migration! Test #5 failed.",
);

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