//
//  VerletShapeTests.cpp
//  tests/physics/src
//
//  Created by Andrew Meadows on 02/21/2014.
//  Copyright 2014 High Fidelity, Inc.
//
//  Distributed under the Apache License, Version 2.0.
//  See the accompanying file LICENSE or http://www.apache.org/licenses/LICENSE-2.0.html
//

//#include <stdio.h>
#include <iostream>
#include <math.h>

#include <glm/glm.hpp>
#include <glm/gtx/quaternion.hpp>

#include <CollisionInfo.h>
#include <Ragdoll.h>    // for VerletPoint
#include <ShapeCollider.h>
#include <SharedUtil.h>
#include <VerletCapsuleShape.h>
#include <VerletSphereShape.h>
#include <StreamUtils.h>

#include "VerletShapeTests.h"

const glm::vec3 origin(0.0f);
static const glm::vec3 xAxis(1.0f, 0.0f, 0.0f);
static const glm::vec3 yAxis(0.0f, 1.0f, 0.0f);
static const glm::vec3 zAxis(0.0f, 0.0f, 1.0f);

void VerletShapeTests::setSpherePosition() {
    float radius = 1.0f;
    glm::vec3 offset(1.23f, 4.56f, 7.89f);
    VerletPoint point;
    VerletSphereShape sphere(radius, &point);

    point._position = glm::vec3(0.f);
    float d = glm::distance(glm::vec3(0.0f), sphere.getTranslation());
    if (d != 0.0f) {
        std::cout << __FILE__ << ":" << __LINE__ << " ERROR: sphere should be at origin" << std::endl;
    }

    point._position = offset;
    d = glm::distance(glm::vec3(0.0f), sphere.getTranslation());
    if (d != glm::length(offset)) {
        std::cout << __FILE__ << ":" << __LINE__ << " ERROR: sphere should be at offset" << std::endl;
    }
}

void VerletShapeTests::sphereMissesSphere() {
    // non-overlapping spheres of unequal size

    float radiusA = 7.0f;
    float radiusB = 3.0f;
    float alpha = 1.2f;
    float beta = 1.3f;
    glm::vec3 offsetDirection = glm::normalize(glm::vec3(1.0f, 2.0f, 3.0f));
    float offsetDistance = alpha * radiusA + beta * radiusB;

    // create points for the sphere centers
    VerletPoint points[2];

    // give pointers to the spheres
    VerletSphereShape sphereA(radiusA, (points + 0));
    VerletSphereShape sphereB(radiusB, (points + 1));

    // set the positions of the spheres by slamming the points directly
    points[0]._position = origin;
    points[1]._position = offsetDistance * offsetDirection;

    CollisionList collisions(16);

    // collide A to B...
    {
        bool touching = ShapeCollider::collideShapes(&sphereA, &sphereB, collisions);
        if (touching) {
            std::cout << __FILE__ << ":" << __LINE__
                << " ERROR: sphereA and sphereB should NOT touch" << std::endl;
        }
    }

    // collide B to A...
    {
        bool touching = ShapeCollider::collideShapes(&sphereB, &sphereA, collisions);
        if (touching) {
            std::cout << __FILE__ << ":" << __LINE__
                << " ERROR: sphereA and sphereB should NOT touch" << std::endl;
        }
    }

    // also test shapeShape
    {
        bool touching = ShapeCollider::collideShapes(&sphereB, &sphereA, collisions);
        if (touching) {
            std::cout << __FILE__ << ":" << __LINE__
                << " ERROR: sphereA and sphereB should NOT touch" << std::endl;
        }
    }

    if (collisions.size() > 0) {
        std::cout << __FILE__ << ":" << __LINE__
            << " ERROR: expected empty collision list but size is " << collisions.size() << std::endl;
    }
}

void VerletShapeTests::sphereTouchesSphere() {
    // overlapping spheres of unequal size
    float radiusA = 7.0f;
    float radiusB = 3.0f;
    float alpha = 0.2f;
    float beta = 0.3f;
    glm::vec3 offsetDirection = glm::normalize(glm::vec3(1.0f, 2.0f, 3.0f));
    float offsetDistance = alpha * radiusA + beta * radiusB;
    float expectedPenetrationDistance = (1.0f - alpha) * radiusA + (1.0f - beta) * radiusB;
    glm::vec3 expectedPenetration = expectedPenetrationDistance * offsetDirection;

    // create two points for the sphere centers
    VerletPoint points[2];

    // give pointers to the spheres
    VerletSphereShape sphereA(radiusA, points+0);
    VerletSphereShape sphereB(radiusB, points+1);

    // set the positions of the spheres by slamming the points directly
    points[0]._position = origin;
    points[1]._position = offsetDistance * offsetDirection;

    CollisionList collisions(16);
    int numCollisions = 0;

    // collide A to B...
    {
        bool touching = ShapeCollider::collideShapes(&sphereA, &sphereB, collisions);
        if (!touching) {
            std::cout << __FILE__ << ":" << __LINE__
                << " ERROR: sphereA and sphereB should touch" << std::endl;
        } else {
            ++numCollisions;
        }

        // verify state of collisions
        if (numCollisions != collisions.size()) {
            std::cout << __FILE__ << ":" << __LINE__
                << " ERROR: expected collisions size of " << numCollisions << " but actual size is " << collisions.size()
                << std::endl;
        }
        CollisionInfo* collision = collisions.getCollision(numCollisions - 1);
        if (!collision) {
            std::cout << __FILE__ << ":" << __LINE__
                << " ERROR: null collision" << std::endl;
        }
    
        // penetration points from sphereA into sphereB
        float inaccuracy = glm::length(collision->_penetration - expectedPenetration);
        if (fabs(inaccuracy) > EPSILON) {
            std::cout << __FILE__ << ":" << __LINE__
                << " ERROR: bad penetration: expected = " << expectedPenetration
                << " actual = " << collision->_penetration << std::endl;
        }
    
        // contactPoint is on surface of sphereA
        glm::vec3 AtoB = sphereB.getTranslation() - sphereA.getTranslation();
        glm::vec3 expectedContactPoint = sphereA.getTranslation() + radiusA * glm::normalize(AtoB);
        inaccuracy = glm::length(collision->_contactPoint - expectedContactPoint);
        if (fabs(inaccuracy) > EPSILON) {
            std::cout << __FILE__ << ":" << __LINE__
                << " ERROR: bad contactPoint: expected = " << expectedContactPoint
                << " actual = " << collision->_contactPoint << std::endl;
        }
    }

    // collide B to A...
    {
        bool touching = ShapeCollider::collideShapes(&sphereB, &sphereA, collisions);
        if (!touching) {
            std::cout << __FILE__ << ":" << __LINE__
                << " ERROR: sphereA and sphereB should touch" << std::endl;
        } else {
            ++numCollisions;
        }
    
        // penetration points from sphereA into sphereB
        CollisionInfo* collision = collisions.getCollision(numCollisions - 1);
        float inaccuracy = glm::length(collision->_penetration + expectedPenetration);
        if (fabs(inaccuracy) > EPSILON) {
            std::cout << __FILE__ << ":" << __LINE__
                << " ERROR: bad penetration: expected = " << expectedPenetration
                << " actual = " << collision->_penetration << std::endl;
        }
    
        // contactPoint is on surface of sphereA
        glm::vec3 BtoA = sphereA.getTranslation() - sphereB.getTranslation();
        glm::vec3 expectedContactPoint = sphereB.getTranslation() + radiusB * glm::normalize(BtoA);
        inaccuracy = glm::length(collision->_contactPoint - expectedContactPoint);
        if (fabs(inaccuracy) > EPSILON) {
            std::cout << __FILE__ << ":" << __LINE__
                << " ERROR: bad contactPoint: expected = " << expectedContactPoint
                << " actual = " << collision->_contactPoint << std::endl;
        }
    }
}

void VerletShapeTests::sphereMissesCapsule() {
    // non-overlapping sphere and capsule
    float radiusA = 1.5f;
    float radiusB = 2.3f;
    float totalRadius = radiusA + radiusB;
    float halfHeightB = 1.7f;
    float axialOffset = totalRadius + 1.1f * halfHeightB;
    float radialOffset = 1.2f * radiusA + 1.3f * radiusB;
    
    // create points for the sphere + capsule
    VerletPoint points[3];
    for (int i = 0; i < 3; ++i) {
        points[i]._position = glm::vec3(0.0f);
    }

    // give the points to the shapes
    VerletSphereShape sphereA(radiusA, points);
    VerletCapsuleShape capsuleB(radiusB, points+1, points+2);
    capsuleB.setHalfHeight(halfHeightB);

    // give the capsule some arbitrary transform
    float angle = 37.8f;
    glm::vec3 axis = glm::normalize( glm::vec3(-7.0f, 2.8f, 9.3f) );
    glm::quat rotation = glm::angleAxis(angle, axis);
    glm::vec3 translation(15.1f, -27.1f, -38.6f);
    capsuleB.setRotation(rotation);
    capsuleB.setTranslation(translation);

    CollisionList collisions(16);

    // walk sphereA along the local yAxis next to, but not touching, capsuleB
    glm::vec3 localStartPosition(radialOffset, axialOffset, 0.0f);
    int numberOfSteps = 10;
    float delta = 1.3f * (totalRadius + halfHeightB) / (numberOfSteps - 1);
    for (int i = 0; i < numberOfSteps; ++i) {
        // translate sphereA into world-frame
        glm::vec3 localPosition = localStartPosition + ((float)i * delta) * yAxis;
        sphereA.setTranslation(rotation * localPosition + translation);

        // sphereA agains capsuleB
        if (ShapeCollider::collideShapes(&sphereA, &capsuleB, collisions))
        {
            std::cout << __FILE__ << ":" << __LINE__
                << " ERROR: sphere and capsule should NOT touch" << std::endl;
        }

        // capsuleB against sphereA
        if (ShapeCollider::collideShapes(&capsuleB, &sphereA, collisions))
        {
            std::cout << __FILE__ << ":" << __LINE__
                << " ERROR: sphere and capsule should NOT touch" << std::endl;
        }
    }

    if (collisions.size() > 0) {
        std::cout << __FILE__ << ":" << __LINE__
            << " ERROR: expected empty collision list but size is " << collisions.size() << std::endl;
    }
}

void VerletShapeTests::sphereTouchesCapsule() {
    // overlapping sphere and capsule
    float radiusA = 2.0f;
    float radiusB = 1.0f;
    float totalRadius = radiusA + radiusB;
    float halfHeightB = 2.0f;
    float alpha = 0.5f;
    float beta = 0.5f;
    float radialOffset = alpha * radiusA + beta * radiusB;
    
    // create points for the sphere + capsule
    VerletPoint points[3];
    for (int i = 0; i < 3; ++i) {
        points[i]._position = glm::vec3(0.0f);
    }

    // give the points to the shapes
    VerletSphereShape sphereA(radiusA, points);
    VerletCapsuleShape capsuleB(radiusB, points+1, points+2);
    capsuleB.setHalfHeight(halfHeightB);

    CollisionList collisions(16);
    int numCollisions = 0;

    {   // sphereA collides with capsuleB's cylindrical wall
        sphereA.setTranslation(radialOffset * xAxis);

        if (!ShapeCollider::collideShapes(&sphereA, &capsuleB, collisions))
        {
            std::cout << __FILE__ << ":" << __LINE__
                << " ERROR: sphere and capsule should touch" << std::endl;
        } else {
            ++numCollisions;
        }
    
        // penetration points from sphereA into capsuleB
        CollisionInfo* collision = collisions.getCollision(numCollisions - 1);
        glm::vec3 expectedPenetration = (radialOffset - totalRadius) * xAxis;
        float inaccuracy = glm::length(collision->_penetration - expectedPenetration);
        if (fabs(inaccuracy) > EPSILON) {
            std::cout << __FILE__ << ":" << __LINE__
                << " ERROR: bad penetration: expected = " << expectedPenetration
                << " actual = " << collision->_penetration << std::endl;
        }
    
        // contactPoint is on surface of sphereA
        glm::vec3 expectedContactPoint = sphereA.getTranslation() - radiusA * xAxis;
        inaccuracy = glm::length(collision->_contactPoint - expectedContactPoint);
        if (fabs(inaccuracy) > EPSILON) {
            std::cout << __FILE__ << ":" << __LINE__
                << " ERROR: bad contactPoint: expected = " << expectedContactPoint
                << " actual = " << collision->_contactPoint << std::endl;
        }

        // capsuleB collides with sphereA
        if (!ShapeCollider::collideShapes(&capsuleB, &sphereA, collisions))
        {
            std::cout << __FILE__ << ":" << __LINE__
                << " ERROR: capsule and sphere should touch" << std::endl;
        } else {
            ++numCollisions;
        }
    
        // penetration points from sphereA into capsuleB
        collision = collisions.getCollision(numCollisions - 1);
        expectedPenetration = - (radialOffset - totalRadius) * xAxis;
        if (collision->_shapeA == &sphereA) {
            // the ShapeCollider swapped the order of the shapes
            expectedPenetration *= -1.0f;
        }
        inaccuracy = glm::length(collision->_penetration - expectedPenetration);
        if (fabs(inaccuracy) > EPSILON) {
            std::cout << __FILE__ << ":" << __LINE__
                << " ERROR: bad penetration: expected = " << expectedPenetration
                << " actual = " << collision->_penetration << std::endl;
        }
    
        // contactPoint is on surface of capsuleB
        glm::vec3 BtoA = sphereA.getTranslation() - capsuleB.getTranslation();
        glm::vec3 closestApproach = capsuleB.getTranslation() + glm::dot(BtoA, yAxis) * yAxis;
        expectedContactPoint = closestApproach + radiusB * glm::normalize(BtoA - closestApproach);
        if (collision->_shapeA == &sphereA) {
            // the ShapeCollider swapped the order of the shapes
            closestApproach = sphereA.getTranslation() - glm::dot(BtoA, yAxis) * yAxis;
            expectedContactPoint = closestApproach - radiusB * glm::normalize(BtoA - closestApproach);
        }
        inaccuracy = glm::length(collision->_contactPoint - expectedContactPoint);
        if (fabs(inaccuracy) > EPSILON) {
            std::cout << __FILE__ << ":" << __LINE__
                << " ERROR: bad contactPoint: expected = " << expectedContactPoint
                << " actual = " << collision->_contactPoint << std::endl;
        }
    }
    {   // sphereA hits end cap at axis
        glm::vec3 axialOffset = (halfHeightB + alpha * radiusA + beta * radiusB) * yAxis;
        sphereA.setTranslation(axialOffset);
        
        if (!ShapeCollider::collideShapes(&sphereA, &capsuleB, collisions))
        {
            std::cout << __FILE__ << ":" << __LINE__
                << " ERROR: sphere and capsule should touch" << std::endl;
        } else {
            ++numCollisions;
        }
    
        // penetration points from sphereA into capsuleB
        CollisionInfo* collision = collisions.getCollision(numCollisions - 1);
        glm::vec3 expectedPenetration = - ((1.0f - alpha) * radiusA + (1.0f - beta) * radiusB) * yAxis;
        float inaccuracy = glm::length(collision->_penetration - expectedPenetration);
        if (fabs(inaccuracy) > EPSILON) {
            std::cout << __FILE__ << ":" << __LINE__
                << " ERROR: bad penetration: expected = " << expectedPenetration
                << " actual = " << collision->_penetration << std::endl;
        }
    
        // contactPoint is on surface of sphereA
        glm::vec3 expectedContactPoint = sphereA.getTranslation() - radiusA * yAxis;
        inaccuracy = glm::length(collision->_contactPoint - expectedContactPoint);
        if (fabs(inaccuracy) > EPSILON) {
            std::cout << __FILE__ << ":" << __LINE__
                << " ERROR: bad contactPoint: expected = " << expectedContactPoint
                << " actual = " << collision->_contactPoint << std::endl;
        }

        // capsuleB collides with sphereA
        if (!ShapeCollider::collideShapes(&capsuleB, &sphereA, collisions))
        {
            std::cout << __FILE__ << ":" << __LINE__
                << " ERROR: capsule and sphere should touch" << std::endl;
        } else {
            ++numCollisions;
        }
    
        // penetration points from sphereA into capsuleB
        collision = collisions.getCollision(numCollisions - 1);
        expectedPenetration = ((1.0f - alpha) * radiusA + (1.0f - beta) * radiusB) * yAxis;
        if (collision->_shapeA == &sphereA) {
            // the ShapeCollider swapped the order of the shapes
            expectedPenetration *= -1.0f;
        }
        inaccuracy = glm::length(collision->_penetration - expectedPenetration);
        if (fabs(inaccuracy) > EPSILON) {
            std::cout << __FILE__ << ":" << __LINE__
                << " ERROR: bad penetration: expected = " << expectedPenetration
                << " actual = " << collision->_penetration << std::endl;
        }
    
        // contactPoint is on surface of capsuleB
        glm::vec3 endPoint;
        capsuleB.getEndPoint(endPoint);
        expectedContactPoint = endPoint + radiusB * yAxis;
        if (collision->_shapeA == &sphereA) {
            // the ShapeCollider swapped the order of the shapes
            expectedContactPoint = axialOffset - radiusA * yAxis;
        }
        inaccuracy = glm::length(collision->_contactPoint - expectedContactPoint);
        if (fabs(inaccuracy) > EPSILON) {
            std::cout << __FILE__ << ":" << __LINE__
                << " ERROR: bad contactPoint: expected = " << expectedContactPoint
                << " actual = " << collision->_contactPoint << std::endl;
        }
    }
    {   // sphereA hits start cap at axis
        glm::vec3 axialOffset = - (halfHeightB + alpha * radiusA + beta * radiusB) * yAxis;
        sphereA.setTranslation(axialOffset);
        
        if (!ShapeCollider::collideShapes(&sphereA, &capsuleB, collisions))
        {
            std::cout << __FILE__ << ":" << __LINE__
                << " ERROR: sphere and capsule should touch" << std::endl;
        } else {
            ++numCollisions;
        }
    
        // penetration points from sphereA into capsuleB
        CollisionInfo* collision = collisions.getCollision(numCollisions - 1);
        glm::vec3 expectedPenetration = ((1.0f - alpha) * radiusA + (1.0f - beta) * radiusB) * yAxis;
        float inaccuracy = glm::length(collision->_penetration - expectedPenetration);
        if (fabs(inaccuracy) > EPSILON) {
            std::cout << __FILE__ << ":" << __LINE__
                << " ERROR: bad penetration: expected = " << expectedPenetration
                << " actual = " << collision->_penetration << std::endl;
        }
    
        // contactPoint is on surface of sphereA
        glm::vec3 expectedContactPoint = sphereA.getTranslation() + radiusA * yAxis;
        inaccuracy = glm::length(collision->_contactPoint - expectedContactPoint);
        if (fabs(inaccuracy) > EPSILON) {
            std::cout << __FILE__ << ":" << __LINE__
                << " ERROR: bad contactPoint: expected = " << expectedContactPoint
                << " actual = " << collision->_contactPoint << std::endl;
        }

        // capsuleB collides with sphereA
        if (!ShapeCollider::collideShapes(&capsuleB, &sphereA, collisions))
        {
            std::cout << __FILE__ << ":" << __LINE__
                << " ERROR: capsule and sphere should touch" << std::endl;
        } else {
            ++numCollisions;
        }
    
        // penetration points from sphereA into capsuleB
        collision = collisions.getCollision(numCollisions - 1);
        expectedPenetration = - ((1.0f - alpha) * radiusA + (1.0f - beta) * radiusB) * yAxis;
        if (collision->_shapeA == &sphereA) {
            // the ShapeCollider swapped the order of the shapes
            expectedPenetration *= -1.0f;
        }
        inaccuracy = glm::length(collision->_penetration - expectedPenetration);
        if (fabs(inaccuracy) > EPSILON) {
            std::cout << __FILE__ << ":" << __LINE__
                << " ERROR: bad penetration: expected = " << expectedPenetration
                << " actual = " << collision->_penetration << std::endl;
        }
    
        // contactPoint is on surface of capsuleB
        glm::vec3 startPoint;
        capsuleB.getStartPoint(startPoint);
        expectedContactPoint = startPoint - radiusB * yAxis;
        if (collision->_shapeA == &sphereA) {
            // the ShapeCollider swapped the order of the shapes
            expectedContactPoint = axialOffset + radiusA * yAxis;
        }
        inaccuracy = glm::length(collision->_contactPoint - expectedContactPoint);
        if (fabs(inaccuracy) > EPSILON) {
            std::cout << __FILE__ << ":" << __LINE__
                << " ERROR: bad contactPoint: expected = " << expectedContactPoint
                << " actual = " << collision->_contactPoint << std::endl;
        }
    }
    if (collisions.size() != numCollisions) {
        std::cout << __FILE__ << ":" << __LINE__
            << " ERROR: expected " << numCollisions << " collisions but actual number is " << collisions.size()
            << std::endl;
    }
}

void VerletShapeTests::capsuleMissesCapsule() {
    // non-overlapping capsules
    float radiusA = 2.0f;
    float halfHeightA = 3.0f;
    float radiusB = 3.0f;
    float halfHeightB = 4.0f;

    float totalRadius = radiusA + radiusB;
    float totalHalfLength = totalRadius + halfHeightA + halfHeightB;

    // create points for the shapes
    VerletPoint points[4];
    for (int i = 0; i < 4; ++i) {
        points[i]._position = glm::vec3(0.0f);
    }

    // give the points to the shapes
    VerletCapsuleShape capsuleA(radiusA, points+0, points+1);
    VerletCapsuleShape capsuleB(radiusB, points+2, points+3);
    capsuleA.setHalfHeight(halfHeightA);
    capsuleA.setHalfHeight(halfHeightB);

    CollisionList collisions(16);

    // side by side
    capsuleB.setTranslation((1.01f * totalRadius) * xAxis);
    if (ShapeCollider::collideShapes(&capsuleA, &capsuleB, collisions))
    {
        std::cout << __FILE__ << ":" << __LINE__
            << " ERROR: capsule and capsule should NOT touch" << std::endl;
    }
    if (ShapeCollider::collideShapes(&capsuleB, &capsuleA, collisions))
    {
        std::cout << __FILE__ << ":" << __LINE__
            << " ERROR: capsule and capsule should NOT touch" << std::endl;
    }

    // end to end
    capsuleB.setTranslation((1.01f * totalHalfLength) * xAxis);
    if (ShapeCollider::collideShapes(&capsuleA, &capsuleB, collisions))
    {
        std::cout << __FILE__ << ":" << __LINE__
            << " ERROR: capsule and capsule should NOT touch" << std::endl;
    }
    if (ShapeCollider::collideShapes(&capsuleB, &capsuleA, collisions))
    {
        std::cout << __FILE__ << ":" << __LINE__
            << " ERROR: capsule and capsule should NOT touch" << std::endl;
    }

    // rotate B and move it to the side
    glm::quat rotation = glm::angleAxis(PI_OVER_TWO, zAxis);
    capsuleB.setRotation(rotation);
    capsuleB.setTranslation((1.01f * (totalRadius + capsuleB.getHalfHeight())) * xAxis);
    if (ShapeCollider::collideShapes(&capsuleA, &capsuleB, collisions))
    {
        std::cout << __FILE__ << ":" << __LINE__
            << " ERROR: capsule and capsule should NOT touch" << std::endl;
    }
    if (ShapeCollider::collideShapes(&capsuleB, &capsuleA, collisions))
    {
        std::cout << __FILE__ << ":" << __LINE__
            << " ERROR: capsule and capsule should NOT touch" << std::endl;
    }

    if (collisions.size() > 0) {
        std::cout << __FILE__ << ":" << __LINE__
            << " ERROR: expected empty collision list but size is " << collisions.size() << std::endl;
    }
}

void VerletShapeTests::capsuleTouchesCapsule() {
    // overlapping capsules
    float radiusA = 2.0f;
    float halfHeightA = 3.0f;
    float radiusB = 3.0f;
    float halfHeightB = 4.0f;

    float totalRadius = radiusA + radiusB;
    float totalHalfLength = totalRadius + halfHeightA + halfHeightB;

    // create points for the shapes
    VerletPoint points[4];
    for (int i = 0; i < 4; ++i) {
        points[i]._position = glm::vec3(0.0f);
    }

    // give the points to the shapes
    VerletCapsuleShape capsuleA(radiusA, points+0, points+1);
    VerletCapsuleShape capsuleB(radiusB, points+2, points+3);
    capsuleA.setHalfHeight(halfHeightA);
    capsuleB.setHalfHeight(halfHeightB);

    CollisionList collisions(16);
    int numCollisions = 0;

    { // side by side
        capsuleB.setTranslation((0.99f * totalRadius) * xAxis);
        if (!ShapeCollider::collideShapes(&capsuleA, &capsuleB, collisions))
        {
            std::cout << __FILE__ << ":" << __LINE__
                << " ERROR: capsule and capsule should touch" << std::endl;
        } else {
            ++numCollisions;
        }
        if (!ShapeCollider::collideShapes(&capsuleB, &capsuleA, collisions))
        {
            std::cout << __FILE__ << ":" << __LINE__
                << " ERROR: capsule and capsule should touch" << std::endl;
        } else {
            ++numCollisions;
        }
    }

    { // end to end
        capsuleB.setTranslation((0.99f * totalHalfLength) * yAxis);

        if (!ShapeCollider::collideShapes(&capsuleA, &capsuleB, collisions))
        {
            std::cout << __FILE__ << ":" << __LINE__
                << " ERROR: capsule and capsule should touch" << std::endl;
        } else {
            ++numCollisions;
        }
        if (!ShapeCollider::collideShapes(&capsuleB, &capsuleA, collisions))
        {
            std::cout << __FILE__ << ":" << __LINE__
                << " ERROR: capsule and capsule should touch" << std::endl;
        } else {
            ++numCollisions;
        }
    }

    { // rotate B and move it to the side
        glm::quat rotation = glm::angleAxis(PI_OVER_TWO, zAxis);
        capsuleB.setRotation(rotation);
        capsuleB.setTranslation((0.99f * (totalRadius + capsuleB.getHalfHeight())) * xAxis);

        if (!ShapeCollider::collideShapes(&capsuleA, &capsuleB, collisions))
        {
            std::cout << __FILE__ << ":" << __LINE__
                << " ERROR: capsule and capsule should touch" << std::endl;
        } else {
            ++numCollisions;
        }
        if (!ShapeCollider::collideShapes(&capsuleB, &capsuleA, collisions))
        {
            std::cout << __FILE__ << ":" << __LINE__
                << " ERROR: capsule and capsule should touch" << std::endl;
        } else {
            ++numCollisions;
        }
    }

    { // again, but this time check collision details
        float overlap = 0.1f;
        glm::quat rotation = glm::angleAxis(PI_OVER_TWO, zAxis);
        capsuleB.setRotation(rotation);
        glm::vec3 positionB = ((totalRadius + capsuleB.getHalfHeight()) - overlap) * xAxis;
        capsuleB.setTranslation(positionB);

        // capsuleA vs capsuleB
        if (!ShapeCollider::collideShapes(&capsuleA, &capsuleB, collisions))
        {
            std::cout << __FILE__ << ":" << __LINE__
                << " ERROR: capsule and capsule should touch" << std::endl;
        } else {
            ++numCollisions;
        }
    
        CollisionInfo* collision = collisions.getCollision(numCollisions - 1);
        glm::vec3 expectedPenetration = overlap * xAxis;
        float inaccuracy = glm::length(collision->_penetration - expectedPenetration);
        if (fabs(inaccuracy) > EPSILON) {
            std::cout << __FILE__ << ":" << __LINE__
                << " ERROR: bad penetration: expected = " << expectedPenetration
                << " actual = " << collision->_penetration << std::endl;
        }
    
        glm::vec3 expectedContactPoint = capsuleA.getTranslation() + radiusA * xAxis;
        inaccuracy = glm::length(collision->_contactPoint - expectedContactPoint);
        if (fabs(inaccuracy) > EPSILON) {
            std::cout << __FILE__ << ":" << __LINE__
                << " ERROR: bad contactPoint: expected = " << expectedContactPoint
                << " actual = " << collision->_contactPoint << std::endl;
        }

        // capsuleB vs capsuleA
        if (!ShapeCollider::collideShapes(&capsuleB, &capsuleA, collisions))
        {
            std::cout << __FILE__ << ":" << __LINE__
                << " ERROR: capsule and capsule should touch" << std::endl;
        } else {
            ++numCollisions;
        }
    
        collision = collisions.getCollision(numCollisions - 1);
        expectedPenetration = - overlap * xAxis;
        inaccuracy = glm::length(collision->_penetration - expectedPenetration);
        if (fabs(inaccuracy) > EPSILON) {
            std::cout << __FILE__ << ":" << __LINE__
                << " ERROR: bad penetration: expected = " << expectedPenetration
                << " actual = " << collision->_penetration << std::endl;
        }
    
        expectedContactPoint = capsuleB.getTranslation() - (radiusB + halfHeightB) * xAxis;
        inaccuracy = glm::length(collision->_contactPoint - expectedContactPoint);
        if (fabs(inaccuracy) > EPSILON) {
            std::cout << __FILE__ << ":" << __LINE__
                << " ERROR: bad contactPoint: expected = " << expectedContactPoint
                << " actual = " << collision->_contactPoint << std::endl;
        }
    }

    { // collide cylinder wall against cylinder wall
        float overlap = 0.137f;
        float shift = 0.317f * halfHeightA;
        glm::quat rotation = glm::angleAxis(PI_OVER_TWO, zAxis);
        capsuleB.setRotation(rotation);
        glm::vec3 positionB = (totalRadius - overlap) * zAxis + shift * yAxis;
        capsuleB.setTranslation(positionB);

        // capsuleA vs capsuleB
        if (!ShapeCollider::collideShapes(&capsuleA, &capsuleB, collisions))
        {
            std::cout << __FILE__ << ":" << __LINE__
                << " ERROR: capsule and capsule should touch" << std::endl;
        } else {
            ++numCollisions;
        }
    
        CollisionInfo* collision = collisions.getCollision(numCollisions - 1);
        glm::vec3 expectedPenetration = overlap * zAxis;
        float inaccuracy = glm::length(collision->_penetration - expectedPenetration);
        if (fabs(inaccuracy) > EPSILON) {
            std::cout << __FILE__ << ":" << __LINE__
                << " ERROR: bad penetration: expected = " << expectedPenetration
                << " actual = " << collision->_penetration << std::endl;
        }
    
        glm::vec3 expectedContactPoint = capsuleA.getTranslation() + radiusA * zAxis + shift * yAxis;
        inaccuracy = glm::length(collision->_contactPoint - expectedContactPoint);
        if (fabs(inaccuracy) > EPSILON) {
            std::cout << __FILE__ << ":" << __LINE__
                << " ERROR: bad contactPoint: expected = " << expectedContactPoint
                << " actual = " << collision->_contactPoint << std::endl;
        }
    }
}

void VerletShapeTests::runAllTests() {
    ShapeCollider::initDispatchTable();

    setSpherePosition();
    sphereMissesSphere();
    sphereTouchesSphere();

    sphereMissesCapsule();
    sphereTouchesCapsule();

    capsuleMissesCapsule();
    capsuleTouchesCapsule();
}