/** @file logicTests.cpp
* @brief Unit tests for the logic layer of a Rally-X game.
*
* The classes used to run Allegro's install and uninstall functions were tested indirectly
* through the use of other classes. If the AllegroWrappers classes are not working, they will
* result in tests failing, or the program crashing.
*
* The Car class's movement is tested through implementing a subclass of Car, PlayerCar, facing
* in a given direction with and without maze walls in the way, and testing its position after
* a frame has passed.
*
* The counting system with the Checkpoint class is tested through repeated creation and
* destruction of Checkpoint objects.
*
* The CollisionDetecter class is tested by setting up situations with each type of collision,
* and checking that they have the desired results on the objects involved.
*
* The DestroyedObjectPopup class is tested to ensure that it lasts the desired amount of time
* before being destroyed.
*
* The intelligence of the EnemyCar class is not unit tested, as it may change as extra states
* and AI schemes are implemented, possibly including a random element. Therefore, it should be
* tested manually by playing example levels and monitoring if the enemies appear to behave in
* a manner that makes gameplay interesting.
*
* The Game class is not tested directly. It pulls all of the units being tested together into
* a complete game, and so should be tested by running the Game.
*
* The GameObject class is tested indirectly through testing its subclasses.
*
* The LimitedTimeObject class is tested indirectly through the DestroyedObjectPopup and Smokescreen classes.
*
* The Maze class is tested in terms of its ability to construct itself correctly from a list of
* coordinates. It is also tested with the PlayerCar class where the movement of the PlayerCar is
* tested in a Maze.
*
* The MazeMath class is tested by running each of its functions with expected input and output values.
*
* The PlayerCar class is tested on its ability to move correctly as part of the tests for the Car class.
* The functioning of the PlayerCar's petrol system is also tested. Controlling of the PlayerCar
* is not tested, and should be tested manually by running the game and verifying that the arrow keys
* cause the direction of the PlayerCar to change appropriately. Further, the creation of Smokescreens
* by pressing the spacebar should also be tested manually.
*
* The Rock class only has functionality in collisions, and so is tested through the CollisionDetector's
* tests.
*
* The Smokescreen class is tested in that it disappears after a set time. Its affect on the EnemyCar class
* is tested through the CollisionDetector's tests.
*
* @author Justin Wernick
* @author David Schneider
*/

#include <vector>
#include <list>
#include <utility>
using namespace std;

#include <gtest/gtest.h>

#include "../source/logic/CollisionDetector.h"
#include "../source/logic/PlayerCar.h"
#include "../source/logic/EnemyCar.h"
#include "../source/logic/Checkpoint.h"
#include "../source/logic/Rock.h"
#include "../source/logic/Smokescreen.h"
#include "../source/logic/Maze.h"
#include "../source/logic/MazeMath.h"
#include "../source/logic/DestroyedObjectPopup.h"

/**
* @brief Tests that PlayerCar moves the correct amount in the up direction on each frame without obstacles.
*/
TEST(Car, updateMovesPlayerUpInEmptyMaze)
{
    Maze testMaze;
    vector<pair<int,int> > walls;
    testMaze.generateMaze(walls,5,5);

    PlayerCar player(2,2,Maze::UP);

    list<Smokescreen> smokescreens;
    player.update(testMaze, smokescreens);

    double expectX = 2;
    double expectY = 2-player.speed();
    EXPECT_FLOAT_EQ(expectX, player.x());
    EXPECT_FLOAT_EQ(expectY, player.y());
}

/**
* @brief Tests that PlayerCar moves the correct amount in the down direction on each frame without obstacles.
*/
TEST(Car, updateMovesPlayerDownInEmptyMaze)
{
    Maze testMaze;
    vector<pair<int,int> > walls;
    testMaze.generateMaze(walls,5,5);

    PlayerCar player(2,2,Maze::DOWN);

    list<Smokescreen> smokescreens;
    player.update(testMaze, smokescreens);

    double expectX = 2;
    double expectY = 2+player.speed();
    EXPECT_FLOAT_EQ(expectX, player.x());
    EXPECT_FLOAT_EQ(expectY, player.y());
}

/**
* @brief Tests that PlayerCar moves the correct amount in the left direction on each frame without obstacles.
*/
TEST(Car, updateMovesPlayerLeftInEmptyMaze)
{
    Maze testMaze;
    vector<pair<int,int> > walls;
    testMaze.generateMaze(walls,5,5);

    PlayerCar player(2,2,Maze::LEFT);

    list<Smokescreen> smokescreens;
    player.update(testMaze, smokescreens);

    double expectX = 2-player.speed();
    double expectY = 2;
    EXPECT_FLOAT_EQ(expectX, player.x());
    EXPECT_FLOAT_EQ(expectY, player.y());
}

/**
* @brief Tests that PlayerCar moves the correct amount in the right direction on each frame without obstacles.
*/
TEST(Car, updateMovesPlayerRightInEmptyMaze)
{
    Maze testMaze;
    vector<pair<int,int> > walls;
    testMaze.generateMaze(walls,5,5);

    PlayerCar player(2,2,Maze::RIGHT);

    list<Smokescreen> smokescreens;
    player.update(testMaze, smokescreens);

    double expectX = 2+player.speed();
    double expectY = 2;
    EXPECT_FLOAT_EQ(expectX, player.x());
    EXPECT_FLOAT_EQ(expectY, player.y());
}

/**
* @brief Tests that PlayerCar does not move up if the path is blocked.
*/
TEST(Car, carNotMovedWhenPathUpBlocked)
{
    Maze testMaze;
    vector<pair<int,int> > walls;
    walls.push_back(make_pair(3,3));
    testMaze.generateMaze(walls,5,5);

    PlayerCar player(3,4,Maze::UP);

    list<Smokescreen> smokescreens;
    player.update(testMaze, smokescreens);

    double expectX = 3;
    double expectY = 4;
    EXPECT_FLOAT_EQ(expectX, player.x());
    EXPECT_FLOAT_EQ(expectY, player.y());
}
/**
* @brief Tests that PlayerCar does not move down if the path is blocked.
*/
TEST(Car, carNotMovedWhenPathDownBlocked)
{
    Maze testMaze;
    vector<pair<int,int> > walls;
    walls.push_back(make_pair(3,3));
    testMaze.generateMaze(walls,5,5);

    PlayerCar player(3,2,Maze::DOWN);

    list<Smokescreen> smokescreens;
    player.update(testMaze, smokescreens);

    double expectX = 3;
    double expectY = 2;
    EXPECT_FLOAT_EQ(expectX, player.x());
    EXPECT_FLOAT_EQ(expectY, player.y());
}
/**
* @brief Tests that PlayerCar does not move left if the path is blocked.
*/
TEST(Car, carNotMovedWhenPathLeftBlocked)
{
    Maze testMaze;
    vector<pair<int,int> > walls;
    walls.push_back(make_pair(3,3));
    testMaze.generateMaze(walls,5,5);

    PlayerCar player(4,3,Maze::LEFT);

    list<Smokescreen> smokescreens;
    player.update(testMaze, smokescreens);

    double expectX = 4;
    double expectY = 3;
    EXPECT_FLOAT_EQ(expectX, player.x());
    EXPECT_FLOAT_EQ(expectY, player.y());
}
/**
* @brief Tests that PlayerCar does not move right if the path is blocked.
*/
TEST(Car, carNotMovedWhenPathRightBlocked)
{
    Maze testMaze;
    vector<pair<int,int> > walls;
    walls.push_back(make_pair(3,3));
    testMaze.generateMaze(walls,5,5);

    PlayerCar player(2,3,Maze::RIGHT);

    list<Smokescreen> smokescreens;
    player.update(testMaze, smokescreens);

    double expectX = 2;
    double expectY = 3;
    EXPECT_FLOAT_EQ(expectX, player.x());
    EXPECT_FLOAT_EQ(expectY, player.y());
}

/**
* @brief Tests that PlayerCar does not move up if currently on the top row of the maze.
*/
TEST(Car, carDoesNotMoveUpOutMaze)
{
    Maze testMaze;
    vector<pair<int,int> > walls;
    testMaze.generateMaze(walls,5,5);

    PlayerCar player(3,0,Maze::UP);

    list<Smokescreen> smokescreens;
    player.update(testMaze, smokescreens);

    double expectX = 3;
    double expectY = 0;
    EXPECT_FLOAT_EQ(expectX, player.x());
    EXPECT_FLOAT_EQ(expectY, player.y());
}
/**
* @brief Tests that PlayerCar does not move down if currently on the bottom row of the maze.
*/
TEST(Car, carDoesNotMoveDownOutMaze)
{
    Maze testMaze;
    vector<pair<int,int> > walls;
    testMaze.generateMaze(walls,5,5);

    PlayerCar player(3,5,Maze::DOWN);

    list<Smokescreen> smokescreens;
    player.update(testMaze, smokescreens);

    double expectX = 3;
    double expectY = 5;
    EXPECT_FLOAT_EQ(expectX, player.x());
    EXPECT_FLOAT_EQ(expectY, player.y());
}
/**
* @brief Tests that PlayerCar does not move left if currently on the first column of the maze.
*/
TEST(Car, carDoesNotMoveLeftOutMaze)
{
    Maze testMaze;
    vector<pair<int,int> > walls;
    testMaze.generateMaze(walls,5,5);

    PlayerCar player(0,3,Maze::LEFT);

    list<Smokescreen> smokescreens;
    player.update(testMaze, smokescreens);

    double expectX = 0;
    double expectY = 3;
    EXPECT_FLOAT_EQ(expectX, player.x());
    EXPECT_FLOAT_EQ(expectY, player.y());
}
/**
* @brief Tests that PlayerCar does not move right if currently on the last column of the maze.
*/
TEST(Car, carDoesNotMoveRightOutMaze)
{
    Maze testMaze;
    vector<pair<int,int> > walls;
    testMaze.generateMaze(walls,5,5);

    PlayerCar player(5,3,Maze::RIGHT);

    list<Smokescreen> smokescreens;
    player.update(testMaze, smokescreens);

    double expectX = 5;
    double expectY = 3;
    EXPECT_FLOAT_EQ(expectX, player.x());
    EXPECT_FLOAT_EQ(expectY, player.y());
}

/**
* @brief Tests that counting of the number of checkpoints happens correctly.
*/
TEST(Checkpoint, countIncrementsAndDecrements)
{
    vector<Checkpoint> checkpoints;
    EXPECT_EQ(0, Checkpoint::checkpointCount());

    for (int i=0; i<1000; ++i)
    {
        checkpoints.push_back(Checkpoint(i,i));
    }
    EXPECT_EQ(1000, Checkpoint::checkpointCount());

    //brackets to limit scope
    {
        Checkpoint extraCheck1(0,0);
        Checkpoint extraCheck2 = extraCheck1;
        EXPECT_EQ(1002, Checkpoint::checkpointCount());
        extraCheck2 = extraCheck1;
        EXPECT_EQ(1002, Checkpoint::checkpointCount());
    }
    EXPECT_EQ(1000, Checkpoint::checkpointCount());

    while(!checkpoints.empty())
    {
        checkpoints.pop_back();
    }
    EXPECT_EQ(0, Checkpoint::checkpointCount());
}

/**
* @brief Tests that when a player and enemy overlap, both are marked for destruction.
*/
TEST(CollisionDetector, playerAndEnemyBothDestroyed)
{
    list<PlayerCar> players;
    list<EnemyCar> enemies;
    list<Checkpoint> checkpoints;
    list<Rock> rocks;
    list<Smokescreen> smokescreens;
    CollisionDetector detector;

    players.push_back(PlayerCar(5,5));
    players.push_back(PlayerCar(5,6));
    players.push_back(PlayerCar(6,5));
    players.push_back(PlayerCar(7,7.5));

    enemies.push_back(EnemyCar(5,6));
    enemies.push_back(EnemyCar(4,5));
    enemies.push_back(EnemyCar(6,6));
    enemies.push_back(EnemyCar(6.5,8));

    detector.checkCollisions(players, enemies, checkpoints, rocks, smokescreens);

    list<PlayerCar>::const_iterator playerIter = players.begin();
    EXPECT_FALSE(playerIter->destroyed());
    ++playerIter;
    EXPECT_TRUE(playerIter->destroyed());
    ++playerIter;
    EXPECT_FALSE(playerIter->destroyed());
    ++playerIter;
    EXPECT_TRUE(playerIter->destroyed());

    list<EnemyCar>::const_iterator enemyIter = enemies.begin();
    EXPECT_TRUE(enemyIter->destroyed());
    ++enemyIter;
    EXPECT_FALSE(enemyIter->destroyed());
    ++enemyIter;
    EXPECT_FALSE(enemyIter->destroyed());
    ++enemyIter;
    EXPECT_TRUE(enemyIter->destroyed());
}

/**
* @brief Tests that when a player and rock overlap, only the player is marked for destruction.
*/
TEST(CollisionDetector, playerDestroyedByRock)
{
    list<PlayerCar> players;
    list<EnemyCar> enemies;
    list<Checkpoint> checkpoints;
    list<Rock> rocks;
    list<Smokescreen> smokescreens;
    CollisionDetector detector;

    players.push_back(PlayerCar(5,5));
    players.push_back(PlayerCar(5,6));
    players.push_back(PlayerCar(6,5));
    players.push_back(PlayerCar(7,7.5));

    rocks.push_back(Rock(5,6));
    rocks.push_back(Rock(4,5));
    rocks.push_back(Rock(6,6));
    rocks.push_back(Rock(6.5,8));

    detector.checkCollisions(players, enemies, checkpoints, rocks, smokescreens);

    list<PlayerCar>::const_iterator playerIter = players.begin();
    EXPECT_FALSE(playerIter->destroyed());
    ++playerIter;
    EXPECT_TRUE(playerIter->destroyed());
    ++playerIter;
    EXPECT_FALSE(playerIter->destroyed());
    ++playerIter;
    EXPECT_TRUE(playerIter->destroyed());

    list<Rock>::const_iterator rockIter = rocks.begin();
    EXPECT_FALSE(rockIter->destroyed());
    ++rockIter;
    EXPECT_FALSE(rockIter->destroyed());
    ++rockIter;
    EXPECT_FALSE(rockIter->destroyed());
    ++rockIter;
    EXPECT_FALSE(rockIter->destroyed());
}

/**
* @brief Tests that when a player and checkpoint overlap, only the checkpoint is marked for destruction.
*/
TEST(CollisionDetector, checkpointDestroyedByPlayer)
{
    list<PlayerCar> players;
    list<EnemyCar> enemies;
    list<Checkpoint> checkpoints;
    list<Rock> rocks;
    list<Smokescreen> smokescreens;
    CollisionDetector detector;

    players.push_back(PlayerCar(5,5));
    players.push_back(PlayerCar(5,6));
    players.push_back(PlayerCar(6,5));
    players.push_back(PlayerCar(7,7.5));

    checkpoints.push_back(Checkpoint(5,6));
    checkpoints.push_back(Checkpoint(4,5));
    checkpoints.push_back(Checkpoint(6,6));
    checkpoints.push_back(Checkpoint(6.5,8));

    detector.checkCollisions(players, enemies, checkpoints, rocks, smokescreens);

    list<PlayerCar>::const_iterator playerIter = players.begin();
    EXPECT_FALSE(playerIter->destroyed());
    ++playerIter;
    EXPECT_FALSE(playerIter->destroyed());
    ++playerIter;
    EXPECT_FALSE(playerIter->destroyed());
    ++playerIter;
    EXPECT_FALSE(playerIter->destroyed());

    list<Checkpoint>::const_iterator checkpointIter = checkpoints.begin();
    EXPECT_TRUE(checkpointIter->destroyed());
    ++checkpointIter;
    EXPECT_FALSE(checkpointIter->destroyed());
    ++checkpointIter;
    EXPECT_FALSE(checkpointIter->destroyed());
    ++checkpointIter;
    EXPECT_TRUE(checkpointIter->destroyed());
}

/**
* @brief Tests that when an enemy and smokescreen overlap, the enemy's speed becomes zero.
*/
TEST(CollisionDetector, enemyStoppedBySmokescreen)
{
    list<PlayerCar> players;
    list<EnemyCar> enemies;
    list<Checkpoint> checkpoints;
    list<Rock> rocks;
    list<Smokescreen> smokescreens;
    CollisionDetector detector;

    enemies.push_back(EnemyCar(5,5));
    enemies.push_back(EnemyCar(5,6));
    enemies.push_back(EnemyCar(6,5));
    enemies.push_back(EnemyCar(7,7.5));

    smokescreens.push_back(Smokescreen(5,6));
    smokescreens.push_back(Smokescreen(4,5));
    smokescreens.push_back(Smokescreen(6,6));
    smokescreens.push_back(Smokescreen(6.5,8));

    detector.checkCollisions(players, enemies, checkpoints, rocks, smokescreens);

    list<EnemyCar>::const_iterator enemyIter = enemies.begin();
    EXPECT_GT(enemyIter->speed(),0);
    ++enemyIter;
    EXPECT_FLOAT_EQ(0, enemyIter->speed());
    ++enemyIter;
    EXPECT_GT(enemyIter->speed(),0);
    ++enemyIter;
    EXPECT_FLOAT_EQ(0, enemyIter->speed());
}

/**
* @brief Tests that a DestroyedObjectPopup is destroyed 30 frames after it is created.
*/
TEST(DestroyedObjectPopup, destroyedAfterSetTime)
{
    DestroyedObjectPopup testPopup(3,2,BitmapStore::CRASHED_CAR);

    int i=0;
    while (!testPopup.destroyed())
    {
        testPopup.update();
        ++i;
    }

    EXPECT_EQ(30,i);
}

/**
* @brief Tests that the maze treats the undefined area outside its bounds as being walls.
*/
TEST(Maze, queryOutsideBoundsReturnsSolid)
{
    Maze testMaze;
    vector<pair<int,int> > walls;
    testMaze.generateMaze(walls,5,5);

    EXPECT_FALSE(testMaze.getSolid(5,5));
    EXPECT_FALSE(testMaze.getSolid(0,0));
    EXPECT_TRUE(testMaze.getSolid(6,5));
    EXPECT_TRUE(testMaze.getSolid(5,6));
    EXPECT_TRUE(testMaze.getSolid(-1,3));
    EXPECT_TRUE(testMaze.getSolid(3,-1));
}

/**
* @brief Tests that a maze can be generated without extending the width and height for objects.
*/
TEST(Maze, generationWithWallsWithoutObjectMax)
{
    Maze testMaze;
    vector<pair<int,int> > walls;
    walls.push_back(make_pair(1,2));
    walls.push_back(make_pair(4,3));
    testMaze.generateMaze(walls);

    //test random empty blocks
    EXPECT_FALSE(testMaze.getSolid(2,1));
    EXPECT_FALSE(testMaze.getSolid(0,0));

    //test wall blocks
    EXPECT_TRUE(testMaze.getSolid(1,2));
    EXPECT_TRUE(testMaze.getSolid(4,3));

    //test bounds are being set right
    EXPECT_TRUE(testMaze.getSolid(4,4));
    EXPECT_TRUE(testMaze.getSolid(5,3));
}

/**
* @brief Tests that a maze can be generated with extending the width and height for objects.
*/
TEST(Maze, generationWithWallsWithObjectMax)
{
    Maze testMaze;
    vector<pair<int,int> > walls;
    walls.push_back(make_pair(1,2));
    walls.push_back(make_pair(4,3));
    testMaze.generateMaze(walls,5,6);

    //test random empty blocks
    EXPECT_FALSE(testMaze.getSolid(2,1));
    EXPECT_FALSE(testMaze.getSolid(0,0));

    //test wall blocks
    EXPECT_TRUE(testMaze.getSolid(1,2));
    EXPECT_TRUE(testMaze.getSolid(4,3));

    //test bounds are being set right
    EXPECT_FALSE(testMaze.getSolid(4,4));
    EXPECT_FALSE(testMaze.getSolid(5,6));
    EXPECT_TRUE(testMaze.getSolid(6,6));
    EXPECT_TRUE(testMaze.getSolid(5,7));
}

/**
* @brief Tests that the formula for a straight line distance works as expected.
*/
TEST(MazeMath, distanceGivesExpectedResult)
{
    //right angle triange with sides of length 3, 4, and 5
    double x1 = 1;
    double y1 = 1;
    double x2 = 4;
    double y2 = 5;

    double expectedResult = 5;

    EXPECT_DOUBLE_EQ(expectedResult, MazeMath::distance(x1,y1,x2,y2));
}

/**
* @brief Tests that rounding off function works as expected.
*/
TEST(MazeMath, roundGivesExpectedResult)
{
    //right angle triange with sides of length 3, 4, and 5
    double roundUp = 5.5;
    double roundDown = 5.49;

    double expectUp = 6;
    double expectDown = 5;

    EXPECT_DOUBLE_EQ(expectUp, MazeMath::round(roundUp));
    EXPECT_DOUBLE_EQ(expectDown, MazeMath::round(roundDown));
}

/**
* @brief Tests that a PlayerCar can be created and destroyed repeatedly without incident.
*
* This tests that the PlayerCar can handle its own dependencies on Allegro, even when
* copy constructors are used (through vector).
*/
TEST(PlayerCar, creationAndDestructionCanHappen)
{
    EXPECT_NO_THROW({
        vector<PlayerCar> players;
        for (int i=0; i<10; ++i)
        {
            players.push_back(PlayerCar(i,i));
        }
        while(!players.empty())
        {
            players.pop_back();
        }
    });

    EXPECT_FALSE(al_is_system_installed());
}

/**
* @brief Tests that the player's petrol runs out, and that the player's speed is halved after that.
*
* Also tests that the speed is recovered if petrol is increased again.
*/
TEST(PlayerCar, playerSpeedAffectedByPetrol)
{
    Maze testMaze;
    vector<pair<int,int> > walls;
    testMaze.generateMaze(walls,5,5);

    PlayerCar player(5,3,Maze::RIGHT);

    list<Smokescreen> smokescreens;
    for (int i=0; i<1429; ++i)
    {
        player.update(testMaze, smokescreens);
    }

    EXPECT_FLOAT_EQ(0, player.petrol());
    EXPECT_FLOAT_EQ(0.05, player.speed());

    player.gotCheckpoint();
    EXPECT_GT(player.petrol(), 0);
    EXPECT_FLOAT_EQ(0.1, player.speed());
}

/**
* @brief Tests that a Smokescreen is destroyed 60 frames after it is created.
*/
TEST(Smokescreen, destroyedAfterSetTime)
{
    Smokescreen testSmokescreen(3,2);

    int i=0;
    while (!testSmokescreen.destroyed())
    {
        testSmokescreen.update();
        ++i;
    }

    EXPECT_EQ(60,i);
}