// Copyright Epic Games, Inc. All Rights Reserved.

/*=============================================================================
        AnimMontage.cpp: Montage classes that contains slots
=============================================================================*/

#include "Animation/EditorAnimSegment.h"
#include "Animation/AnimMontage.h"

UEditorAnimSegment::UEditorAnimSegment(const FObjectInitializer& ObjectInitializer)
    : Super(ObjectInitializer)
{

    AnimSlotIndex    = 0;
    AnimSegmentIndex = 0;
}

void UEditorAnimSegment::InitAnimSegment(int AnimSlotIndexIn, int AnimSegmentIndexIn)
{
    AnimSlotIndex    = AnimSlotIndexIn;
    AnimSegmentIndex = AnimSegmentIndexIn;
    if (UAnimMontage* Montage = Cast<UAnimMontage>(AnimObject))
    {
        if (Montage->SlotAnimTracks.IsValidIndex(AnimSlotIndex) && Montage->SlotAnimTracks[AnimSlotIndex].AnimTrack.AnimSegments.IsValidIndex(AnimSegmentIndex))
        {
            AnimSegment = Montage->SlotAnimTracks[AnimSlotIndex].AnimTrack.AnimSegments[AnimSegmentIndex];
        }
    }
}

bool UEditorAnimSegment::ApplyChangesToMontage()
{
    if (UAnimMontage* Montage = Cast<UAnimMontage>(AnimObject))
    {
        if (Montage->SlotAnimTracks.IsValidIndex(AnimSlotIndex) && Montage->SlotAnimTracks[AnimSlotIndex].AnimTrack.AnimSegments.IsValidIndex(AnimSegmentIndex))
        {
            if (AnimSegment.AnimReference && AnimSegment.AnimReference->GetSkeleton() == Montage->GetSkeleton())
            {
                Montage->SlotAnimTracks[AnimSlotIndex].AnimTrack.AnimSegments[AnimSegmentIndex] = AnimSegment;
                Montage->UpdateLinkableElements(AnimSlotIndex, AnimSegmentIndex);

                // Need to update linkable elements for segments further along.
                int32 NumSegments = Montage->SlotAnimTracks[AnimSlotIndex].AnimTrack.AnimSegments.Num();
                for (int32 SegmentIdx = AnimSegmentIndex + 1; SegmentIdx < NumSegments; ++SegmentIdx)
                {
                    Montage->UpdateLinkableElements(AnimSlotIndex, SegmentIdx);
                }

                return true;
            }
            else
            {
                AnimSegment.AnimReference = Montage->SlotAnimTracks[AnimSlotIndex].AnimTrack.AnimSegments[AnimSegmentIndex].AnimReference;
                return false;
            }
        }
    }

    return false;
}

bool UEditorAnimSegment::PropertyChangeRequiresRebuild(FPropertyChangedEvent& PropertyChangedEvent)
{
    const FName PropertyName = PropertyChangedEvent.Property ? PropertyChangedEvent.Property->GetFName() : NAME_None;
    if (PropertyName == FName(TEXT("AnimEndTime")) || PropertyName == FName(TEXT("AnimStartTime")) || PropertyName == FName(TEXT("AnimPlayRate")) || PropertyName == FName(TEXT("LoopingCount")))
    {
        // Changing the end or start time of the segment length can't change the order of the montage segments.
        // Return false so that the montage editor does not fully rebuild its UI and we can keep this UEditorAnimSegment object
        // in the details view. (A better solution would be handling the rebuilding in a way that didn't possibly invalidate the UEditorMontageObj in the details view)
        return false;
    }

    return true;
}