/*
 * DiskDurabilityTest.actor.cpp
 *
 * This source file is part of the FoundationDB open source project
 *
 * Copyright 2013-2018 Apple Inc. and the FoundationDB project authors
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include "fdbserver/workloads/workloads.h"
#include "fdbrpc/IAsyncFile.h"
#include "fdbclient/FDBTypes.h"
#include "flow/actorcompiler.h"  // This must be the last #include.

struct DiskDurabilityTest : TestWorkload {
	bool enabled;
	std::string filename;
	KeyRange range, metrics;

	DiskDurabilityTest(WorkloadContext const& wcx)
		: TestWorkload(wcx)
	{
		enabled = !clientId; // only do this on the "first" client
		filename = getOption(options, LiteralStringRef("filename"), LiteralStringRef("durability_test.bin")).toString();
		auto prefix = getOption(options, LiteralStringRef("prefix"), LiteralStringRef("/DiskDurabilityTest/"));
		range = prefixRange( LiteralStringRef("S").withPrefix(prefix) );
		metrics = prefixRange( prefix );
	}

	virtual std::string description() { return "DiskDurabilityTest"; }
	virtual Future<Void> setup( Database const& cx ) { return Void(); }
	virtual Future<Void> start( Database const& cx ) {
		if (enabled)
			return durabilityTest(this, cx);
		return Void();
	}
	virtual Future<bool> check( Database const& cx ) { return true; }
	virtual void getMetrics( vector<PerfMetric>& m ) {}

	Value encodeValue( int64_t x ) {
		x = bigEndian64(x);
		return StringRef( (const uint8_t*)&x, sizeof(x) );
	}
	Key encodeKey( int64_t x ) {
		return encodeValue(x).withPrefix(range.begin);
	}

	int64_t decodeValue( ValueRef k ) {
		ASSERT( k.size() == sizeof(int64_t) );
		return bigEndian64( *(int64_t*)k.begin() );
	}
	int64_t decodeKey( KeyRef k ) { return decodeValue(k.removePrefix(range.begin)); }

	void encodePage( uint8_t* page, int64_t value ) {
		int64_t *ipage = (int64_t*)page;
		for(int i=0; i<4096/8; i++)
			ipage[i] = value + i;
	}
	int64_t decodePage( uint8_t* page ) {
		int64_t *ipage = (int64_t*)page;
		for(int i=0; i<4096/8; i++)
			if (ipage[i] != ipage[0] + i)
				return 0;
		return ipage[0];
	}

	ACTOR static Future<Void> durabilityTest( DiskDurabilityTest* self, Database db ) {
		state Reference<IAsyncFile> file = wait( IAsyncFileSystem::filesystem()->open( self->filename, IAsyncFile::OPEN_CREATE | IAsyncFile::OPEN_READWRITE | IAsyncFile::OPEN_UNBUFFERED | IAsyncFile::OPEN_UNCACHED | IAsyncFile::OPEN_LOCK, 0600 ) );
		state vector<uint8_t> pagedata(4096 * 128);
		state uint8_t* page = (uint8_t*)((intptr_t(&pagedata[0]) | intptr_t(4095)) + 1);

		state int64_t size = wait( file->size() );
		state bool failed = false;

		// Verify
		state Transaction tr(db);
		loop {
			try {
				state Standalone<RangeResultRef> r = wait( tr.getRange( self->range, GetRangeLimits(1000000) ) );
				state int verifyPages = r.size();
				state int i;
				for(i=0; i<r.size(); i++) {
					int bytesRead = wait( file->read( page, 4096, self->decodeKey(r[i].key)*4096 ) );
					if (bytesRead != 4096 || self->decodePage(page) != self->decodeValue(r[i].value)) {
						printf("ValidationError\n");
						TraceEvent(SevError, "ValidationError").detail("At", self->decodeKey(r[i].key)).detail("Expected", self->decodeValue(r[i].value)).detail("Found", self->decodePage(page)).detail("Read", bytesRead);
						failed = true;
					}
				}
				break;
			} catch (Error& e) {
				wait( tr.onError(e) );
			}
		}

		if (failed) throw operation_failed();

		printf("Verified %d/%lld pages\n", verifyPages, size/4096);
		TraceEvent(SevInfo, "Verified").detail("Pages", verifyPages).detail("Of", size/4096);

		// Run
		state bool first = true;
		loop {
			state vector<int64_t> targetPages;
			for(int i=g_random->randomInt(1, 100); i>0 && targetPages.size() < size/4096; i--) {
				auto p = g_random->randomInt(0, size/4096);
				if (!std::count(targetPages.begin(), targetPages.end(), p))
					targetPages.push_back( p );
			}
			for(int i=g_random->randomInt(1,4); i>0; i--) {
				targetPages.push_back( size/4096 );
				size += 4096;
			}

			state vector<int64_t> targetValues(targetPages.size());
			for(auto& v : targetValues)
				v = g_random->randomUniqueID().first();

			tr.reset();
			loop {
				try {
					for(int i=0; i<targetPages.size(); i++)
						tr.clear( self->encodeKey(targetPages[i]) );

					if (!first) {
						Optional<Value> v = wait( tr.get( LiteralStringRef("syncs").withPrefix(self->metrics.begin) ) );
						int64_t count = v.present() ? self->decodeValue(v.get()) : 0;
						count++;
						tr.set( LiteralStringRef("syncs").withPrefix(self->metrics.begin), self->encodeValue( count ) );
					}

					wait( tr.commit() );
					break;
				} catch (Error& e) {
					wait( tr.onError(e) );
				}
			}
			tr.reset();
			state Future<Version> rv = tr.getReadVersion();  // hide this latency

			vector<Future<Void>> fresults;

			for(int i=0; i<targetPages.size(); i++) {
				uint8_t* p = page + 4096*i;
				self->encodePage( p, targetValues[i] );
				fresults.push_back( file->write( p, 4096, targetPages[i]*4096 ) );
			}

			wait( waitForAll( fresults ) );

			wait( file->sync() );

			loop {
				try {
					for(int i=0; i<targetPages.size(); i++)
						tr.set( self->encodeKey(targetPages[i]), self->encodeValue(targetValues[i]) );
					wait( tr.commit() );
					break;
				} catch (Error& e) {
					wait( tr.onError(e) );
				}
			}

			first = false;
		}
	}
};
WorkloadFactory<DiskDurabilityTest> DiskDurabilityTestFactory("DiskDurabilityTest");
