/******************************************************************************
 * Spine Runtimes License Agreement
 * Last updated January 1, 2020. Replaces all prior versions.
 *
 * Copyright (c) 2013-2020, Esoteric Software LLC
 *
 * Integration of the Spine Runtimes into software or otherwise creating
 * derivative works of the Spine Runtimes is permitted under the terms and
 * conditions of Section 2 of the Spine Editor License Agreement:
 * http://esotericsoftware.com/spine-editor-license
 *
 * Otherwise, it is permitted to integrate the Spine Runtimes into software
 * or otherwise create derivative works of the Spine Runtimes (collectively,
 * "Products"), provided that each user of the Products must obtain their own
 * Spine Editor license and redistribution of the Products in any form must
 * include this license and copyright notice.
 *
 * THE SPINE RUNTIMES ARE PROVIDED BY ESOTERIC SOFTWARE LLC "AS IS" AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL ESOTERIC SOFTWARE LLC BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES,
 * BUSINESS INTERRUPTION, OR LOSS OF USE, DATA, OR PROFITS) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THE SPINE RUNTIMES, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *****************************************************************************/

#ifdef SPINE_UE4
    #include "SpinePluginPrivatePCH.h"
#endif

#include <spine/ShearTimeline.h>

#include <spine/Event.h>
#include <spine/Skeleton.h>

#include <spine/Bone.h>
#include <spine/BoneData.h>
#include <spine/Slot.h>
#include <spine/SlotData.h>

using namespace spine;

RTTI_IMPL(ShearTimeline, TranslateTimeline)

ShearTimeline::ShearTimeline(int frameCount) : TranslateTimeline(frameCount) {
}

void ShearTimeline::apply(Skeleton &skeleton, float lastTime, float time, Vector<Event *> *pEvents, float alpha,
                          MixBlend blend, MixDirection direction) {
    SP_UNUSED(lastTime);
    SP_UNUSED(pEvents);
    SP_UNUSED(direction);

    Bone *boneP = skeleton._bones[_boneIndex];
    Bone &bone = *boneP;
    if (!bone._active) return;

    if (time < _frames[0]) {
        switch (blend) {
            case MixBlend_Setup:
                bone._shearX = bone._data._shearX;
                bone._shearY = bone._data._shearY;
                return;
            case MixBlend_First:
                bone._shearX += (bone._data._shearX - bone._shearX) * alpha;
                bone._shearY += (bone._data._shearY - bone._shearY) * alpha;
            default: {
            }
        }
        return;
    }

    float x, y;
    if (time >= _frames[_frames.size() - ENTRIES]) {
        // Time is after last frame.
        x = _frames[_frames.size() + PREV_X];
        y = _frames[_frames.size() + PREV_Y];
    } else {
        // Interpolate between the previous frame and the current frame.
        int frame = Animation::binarySearch(_frames, time, ENTRIES);
        x = _frames[frame + PREV_X];
        y = _frames[frame + PREV_Y];
        float frameTime = _frames[frame];
        float percent = getCurvePercent(frame / ENTRIES - 1,
                                        1 - (time - frameTime) / (_frames[frame + PREV_TIME] - frameTime));

        x = x + (_frames[frame + X] - x) * percent;
        y = y + (_frames[frame + Y] - y) * percent;
    }

    switch (blend) {
        case MixBlend_Setup:
            bone._shearX = bone._data._shearX + x * alpha;
            bone._shearY = bone._data._shearY + y * alpha;
            break;
        case MixBlend_First:
        case MixBlend_Replace:
            bone._shearX += (bone._data._shearX + x - bone._shearX) * alpha;
            bone._shearY += (bone._data._shearY + y - bone._shearY) * alpha;
            break;
        case MixBlend_Add:
            bone._shearX += x * alpha;
            bone._shearY += y * alpha;
    }
}

int ShearTimeline::getPropertyId() {
    return ((int)TimelineType_Shear << 24) + _boneIndex;
}
