/*    Copyright 2012 10gen Inc.
 *
 *    This program is free software: you can redistribute it and/or  modify
 *    it under the terms of the GNU Affero General Public License, version 3,
 *    as published by the Free Software Foundation.
 *
 *    This program is distributed in the hope that it will be useful,
 *    but WITHOUT ANY WARRANTY; without even the implied warranty of
 *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *    GNU Affero General Public License for more details.
 *
 *    You should have received a copy of the GNU Affero General Public License
 *    along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 *    As a special exception, the copyright holders give permission to link the
 *    code of portions of this program with the OpenSSL library under certain
 *    conditions as described in each individual source file and distribute
 *    linked combinations including the program with the OpenSSL library. You
 *    must comply with the GNU Affero General Public License in all respects
 *    for all of the code used other than as permitted herein. If you modify
 *    file(s) with this exception, you may extend this exception to your
 *    version of the file(s), but you are not obligated to do so. If you do not
 *    wish to do so, delete this exception statement from your version. If you
 *    delete this exception statement from all source files in the program,
 *    then also delete it in the license file.
 */

/** Unit tests for OwnedPointerVector. */

#include "mongo/base/owned_pointer_vector.h"

#include <string>
#include <vector>

#include "mongo/unittest/unittest.h"

namespace mongo {
namespace {

    /** Helper class that logs its constructor argument to a static vector on destruction. */
    class DestructionLogger {
    public:
        DestructionLogger( const string& name ) :
            _name( name ) {
        }
        ~DestructionLogger() { _destroyedNames.push_back( _name ); }

        static std::vector<string>& destroyedNames() { return _destroyedNames; }

    private:
        string _name;
        static std::vector<string> _destroyedNames;
    };

    std::vector<string> DestructionLogger::_destroyedNames;

    TEST(OwnedPointerVectorTest, OwnedPointerDestroyed) {
        DestructionLogger::destroyedNames().clear();
        {
            OwnedPointerVector<DestructionLogger> owned;
            owned.mutableVector().push_back( new DestructionLogger( "foo" ) );
            // owned destroyed
        }
        ASSERT_EQUALS( 1U, DestructionLogger::destroyedNames().size() );
        ASSERT_EQUALS( "foo", DestructionLogger::destroyedNames()[ 0 ] );
    }

    TEST(OwnedPointerVectorTest, OwnedConstPointerDestroyed) {
        DestructionLogger::destroyedNames().clear();
        {
            OwnedPointerVector<const DestructionLogger> owned;
            owned.push_back( new DestructionLogger( "foo" ) );
            // owned destroyed
        }
        ASSERT_EQUALS( 1U, DestructionLogger::destroyedNames().size() );
        ASSERT_EQUALS( "foo", DestructionLogger::destroyedNames()[ 0 ] );
    }

    TEST(OwnedPointerVectorTest, OwnedPointersDestroyedInOrder) {
        DestructionLogger::destroyedNames().clear();
        {
            OwnedPointerVector<DestructionLogger> owned;
            owned.push_back( new DestructionLogger( "first" ) );
            owned.push_back( new DestructionLogger( "second" ) );
            // owned destroyed
        }
        ASSERT_EQUALS( 2U, DestructionLogger::destroyedNames().size() );
        ASSERT_EQUALS( "first", DestructionLogger::destroyedNames()[ 0 ] );
        ASSERT_EQUALS( "second", DestructionLogger::destroyedNames()[ 1 ] );
    }

    TEST(OwnedPointerVectorTest, ClearDestroyedInOrder) {
        DestructionLogger::destroyedNames().clear();
        {
            OwnedPointerVector<DestructionLogger> owned;
            owned.push_back( new DestructionLogger( "first" ) );
            owned.push_back( new DestructionLogger( "second" ) );

            owned.clear();
            ASSERT_EQUALS( 2U, DestructionLogger::destroyedNames().size() );
            ASSERT_EQUALS( "first", DestructionLogger::destroyedNames()[ 0 ] );
            ASSERT_EQUALS( "second", DestructionLogger::destroyedNames()[ 1 ] );
            ASSERT_EQUALS( 0U, owned.size() );
            // owned destroyed
        }
        // no additional deletion should have occured when owned was destroyed
        ASSERT_EQUALS( 2U, DestructionLogger::destroyedNames().size() );
    }

    TEST(OwnedPointerVectorTest, EraseDestroysAsCalled) {
        DestructionLogger::destroyedNames().clear();
        {
            // names are order of erasure
            OwnedPointerVector<DestructionLogger> owned;
            owned.push_back( new DestructionLogger( "third" ) );
            owned.push_back( new DestructionLogger( "first" ) );
            owned.push_back( new DestructionLogger( "second" ) );
            owned.push_back( new DestructionLogger( "fourth" ) );

            ASSERT_EQUALS( 0U, DestructionLogger::destroyedNames().size() );

            // erase "first", sliding "second" down to index 1
            owned.erase(owned.begin() + 1);
            ASSERT_EQUALS( 1U, DestructionLogger::destroyedNames().size() );
            ASSERT_EQUALS( "first", DestructionLogger::destroyedNames().back() );
            ASSERT_EQUALS( 3U, owned.size() );

            // erase "second"
            owned.erase(owned.begin() + 1);
            ASSERT_EQUALS( 2U, DestructionLogger::destroyedNames().size() );
            ASSERT_EQUALS( "second", DestructionLogger::destroyedNames().back() );
            ASSERT_EQUALS( 2U, owned.size() );

            // erase "third"
            owned.erase(owned.begin() + 0);
            ASSERT_EQUALS( 3U, DestructionLogger::destroyedNames().size() );
            ASSERT_EQUALS( "third", DestructionLogger::destroyedNames().back() );
            ASSERT_EQUALS( 1U, owned.size() );

            // owned destroyed
        }

        // only "four" should have been deleted when owned was destroyed
        ASSERT_EQUALS( 4U, DestructionLogger::destroyedNames().size() );
        ASSERT_EQUALS( "fourth", DestructionLogger::destroyedNames().back() );
    }

    TEST(OwnedPointerVectorTest, Accessors) {
        OwnedPointerVector<int> owned;
        ASSERT_TRUE( owned.empty() );
        ASSERT_EQUALS( 0U, owned.size() );

        owned.push_back( new int(0) );
        owned.push_back( new int(1) );
        owned.push_back( new int(2) );

        ASSERT_FALSE( owned.empty() );
        ASSERT_EQUALS( 3U, owned.size() );

        ASSERT_EQUALS( 0, *owned[0] );
        ASSERT_EQUALS( 1, *owned[1] );
        ASSERT_EQUALS( 2, *owned[2] );

        ASSERT_EQUALS( 0, *owned.front() );
        ASSERT_EQUALS( 2, *owned.back() );
    }

    TEST(OwnedPointerVectorTest, TransferConstructor) {
        DestructionLogger::destroyedNames().clear();
        {
            OwnedPointerVector<DestructionLogger> source;
            source.push_back( new DestructionLogger( "first" ) );
            source.push_back( new DestructionLogger( "second" ) );

            {
                OwnedPointerVector<DestructionLogger> dest(source.release());
                ASSERT_EQUALS( 0U, DestructionLogger::destroyedNames().size() );
                ASSERT_EQUALS( 0U, source.size() );
                ASSERT_EQUALS( 2U, dest.size() );
                // dest destroyed
            }
            ASSERT_EQUALS( 2U, DestructionLogger::destroyedNames().size() );
            ASSERT_EQUALS( "first", DestructionLogger::destroyedNames()[ 0 ] );
            ASSERT_EQUALS( "second", DestructionLogger::destroyedNames()[ 1 ] );

            // source destroyed
        }
        // no additional deletions
        ASSERT_EQUALS( 2U, DestructionLogger::destroyedNames().size() );
    }

    TEST(OwnedPointerVectorTest, TransferConstructorDoesntModifyArgument) {
        DestructionLogger::destroyedNames().clear();
        {
            std::vector<DestructionLogger*> source;
            source.push_back( new DestructionLogger( "first" ) );
            source.push_back( new DestructionLogger( "second" ) );

            {
                OwnedPointerVector<DestructionLogger> dest(source);
                ASSERT_EQUALS( 0U, DestructionLogger::destroyedNames().size() );
                ASSERT_EQUALS( 2U, source.size() );
                ASSERT_EQUALS( 2U, dest.size() );
                ASSERT( source == dest.vector() ); // can't use ASSERT_EQUALS
                // dest destroyed
            }
            ASSERT_EQUALS( 2U, DestructionLogger::destroyedNames().size() );
            ASSERT_EQUALS( "first", DestructionLogger::destroyedNames()[ 0 ] );
            ASSERT_EQUALS( "second", DestructionLogger::destroyedNames()[ 1 ] );

            ASSERT_EQUALS( 2U, source.size() );
            // source destroyed
        }
        // no additional deletions
        ASSERT_EQUALS( 2U, DestructionLogger::destroyedNames().size() );
    }

    TEST(OwnedPointerVectorTest, TransferAssignment) {
        DestructionLogger::destroyedNames().clear();
        {
            OwnedPointerVector<DestructionLogger> dest;
            {
                OwnedPointerVector<DestructionLogger> source;
                source.push_back( new DestructionLogger( "first" ) );
                source.push_back( new DestructionLogger( "second" ) );

                dest = source.release();
                ASSERT_EQUALS( 0U, DestructionLogger::destroyedNames().size() );
                ASSERT_EQUALS( 0U, source.size() );
                ASSERT_EQUALS( 2U, dest.size() );
                // source destroyed
            }

            ASSERT_EQUALS( 0U, DestructionLogger::destroyedNames().size() );
            ASSERT_EQUALS( 2U, dest.size() );
            // dest destroyed
        }
        ASSERT_EQUALS( 2U, DestructionLogger::destroyedNames().size() );
        ASSERT_EQUALS( "first", DestructionLogger::destroyedNames()[ 0 ] );
        ASSERT_EQUALS( "second", DestructionLogger::destroyedNames()[ 1 ] );
    }

    TEST(OwnedPointerVectorTest, TransferAssignmentDoesntModifyArgument) {
        DestructionLogger::destroyedNames().clear();
        {
            OwnedPointerVector<DestructionLogger> dest;
            {
                std::vector<DestructionLogger*> source;
                source.push_back( new DestructionLogger( "first" ) );
                source.push_back( new DestructionLogger( "second" ) );

                dest = source;
                ASSERT_EQUALS( 0U, DestructionLogger::destroyedNames().size() );
                ASSERT_EQUALS( 2U, source.size() );
                ASSERT_EQUALS( 2U, dest.size() );
                ASSERT( source == dest.vector() ); // can't use ASSERT_EQUALS
                // source destroyed
            }

            ASSERT_EQUALS( 0U, DestructionLogger::destroyedNames().size() );
            ASSERT_EQUALS( 2U, dest.size() );
            // dest destroyed
        }
        ASSERT_EQUALS( 2U, DestructionLogger::destroyedNames().size() );
        ASSERT_EQUALS( "first", DestructionLogger::destroyedNames()[ 0 ] );
        ASSERT_EQUALS( "second", DestructionLogger::destroyedNames()[ 1 ] );
    }

    TEST(OwnedPointerVectorTest, ReleaseAt) {
        DestructionLogger::destroyedNames().clear();

        boost::scoped_ptr<DestructionLogger> holder;
        {
            // names are order of deletion
            OwnedPointerVector<DestructionLogger> owned;
            owned.push_back( new DestructionLogger( "first" ) );
            owned.push_back( new DestructionLogger( "third" ) );
            owned.push_back( new DestructionLogger( "second" ) );

            ASSERT_EQUALS( 0U, DestructionLogger::destroyedNames().size() );

            // transfer ownership of "third" to holder
            holder.reset(owned.releaseAt(1));
            ASSERT_EQUALS( 0U, DestructionLogger::destroyedNames().size() );
            ASSERT_EQUALS( 3U, owned.size() );
            ASSERT_EQUALS( static_cast<DestructionLogger*>(NULL), owned[1] );

            // owned destroyed
        }
        // owned deleted "first" and "second", but not "third"
        ASSERT_EQUALS( 2U, DestructionLogger::destroyedNames().size() );
        ASSERT_EQUALS( "first", DestructionLogger::destroyedNames()[0] );
        ASSERT_EQUALS( "second", DestructionLogger::destroyedNames()[1] );

        // delete "third"
        holder.reset();
        ASSERT_EQUALS( 3U, DestructionLogger::destroyedNames().size() );
        ASSERT_EQUALS( "third", DestructionLogger::destroyedNames().back() );
    }

    TEST(OwnedPointerVectorTest, PopAndReleaseBack) {
        DestructionLogger::destroyedNames().clear();

        {
            // names are order of deletion
            OwnedPointerVector<DestructionLogger> owned;
            owned.push_back( new DestructionLogger( "second" ) );
            owned.push_back( new DestructionLogger( "third" ) );
            owned.push_back( new DestructionLogger( "first" ) );

            ASSERT_EQUALS( 0U, DestructionLogger::destroyedNames().size() );

            {
                // transfer ownership of "third" to holder
                boost::scoped_ptr<DestructionLogger> holder(owned.popAndReleaseBack());
                ASSERT_EQUALS( 0U, DestructionLogger::destroyedNames().size() );
                ASSERT_EQUALS( 2U, owned.size() );
                // holder destroyed
            }
            ASSERT_EQUALS( 1U, DestructionLogger::destroyedNames().size() );
            ASSERT_EQUALS( "first", DestructionLogger::destroyedNames().back() );
            // owned destroyed
        }
        // owned destructor deleted "second" and "third", but not "first"
        ASSERT_EQUALS( 3U, DestructionLogger::destroyedNames().size() );
        ASSERT_EQUALS( "second", DestructionLogger::destroyedNames()[1] );
        ASSERT_EQUALS( "third", DestructionLogger::destroyedNames()[2] );
    }

    TEST(OwnedPointerVectorTest, PopAndDeleteBack) {
        DestructionLogger::destroyedNames().clear();

        {
            // names are order of deletion
            OwnedPointerVector<DestructionLogger> owned;
            owned.push_back( new DestructionLogger( "second" ) );
            owned.push_back( new DestructionLogger( "third" ) );
            owned.push_back( new DestructionLogger( "first" ) );

            ASSERT_EQUALS( 0U, DestructionLogger::destroyedNames().size() );

            owned.popAndDeleteBack();
            ASSERT_EQUALS( 2U, owned.size() );
            ASSERT_EQUALS( 1U, DestructionLogger::destroyedNames().size() );
            ASSERT_EQUALS( "first", DestructionLogger::destroyedNames().back() );
            // owned destroyed
        }
        // owned destructor deleted "second" and "third", but not "first"
        ASSERT_EQUALS( 3U, DestructionLogger::destroyedNames().size() );
        ASSERT_EQUALS( "second", DestructionLogger::destroyedNames()[1] );
        ASSERT_EQUALS( "third", DestructionLogger::destroyedNames()[2] );
    }
    
} // namespace
} // namespace mongo
