#if SPECIAL
#include "main.h"
#endif


static property_channel
Property_InitFloat(real32 Val, real32 ScrubVal, real32 MinVal = PROPERTY_REAL_MIN, real32 MaxVal = PROPERTY_REAL_MAX, bool32 AlwaysInteger = 0);

static block_layer *
Layer_Init(project_data *File, memory *Memory)
{
    if (File->Layer_Count + 1 > MAX_LAYERS) {
        Assert(0);
    }
    block_layer *Layer = (block_layer *)Memory_Block_AllocateAddress(Memory, F_Layers);
    History_Action_Block_Swap(Memory, F_Layers, Layer);

    *Layer = {};
    Layer->Occupied = 1;

    Layer->Block_String_Index = Memory_Block_AllocateNew(Memory, F_Strings);
    block_string *String = (block_string *)Memory_Block_AddressAtIndex(Memory, F_Strings, Layer->Block_String_Index, 0);
    sprintf(String->Char, "Layer %i", File->Layer_Count + 1);  // CSbros...
    History_Action_Swap(Memory, F_Strings, sizeof(String->Occupied), &String->Occupied);
    String->Occupied = 1;

    Layer->x =        Property_InitFloat(0.0f, 1.0f);
    Layer->y =        Property_InitFloat(0.0f, 1.0f);
    Layer->ax =       Property_InitFloat(0.5f, 0.005f);
    Layer->ay =       Property_InitFloat(0.5f, 0.005f);
    Layer->scale =    Property_InitFloat(1.0f, 0.005f);
    Layer->rotation = Property_InitFloat(0.0f, 1.0f);
    Layer->opacity =  Property_InitFloat(1.0f, 0.005f, 0.0f, 1.0f);
    Layer->time =     Property_InitFloat(0.0f, 1.0f, 0, 100000, 1);

    Layer->IsVisible = 1;

    History_Action_Swap(Memory, F_File, sizeof(File->Layer_Count), &File->Layer_Count);
    File->Layer_Count++;

    return Layer;
}

// lots of cleanup...
static void
Layer_Delete(project_data *File, project_state *State, memory *Memory, uint32 Index)
{
    block_layer *Layer = (block_layer *)Memory_Block_AddressAtIndex(Memory, F_Layers, Index);
    History_Action_Block_Swap(Memory, F_Layers, Layer);
    Layer->Occupied = 0;

    block_string *String = (block_string *)Memory_Block_AddressAtIndex(Memory, F_Strings, Layer->Block_String_Index, 0);
    History_Action_Block_Swap(Memory, F_Strings, String);
    String->Occupied = 0;

    for (int i = 0; i < Layer->Block_Effect_Count; i++) {
        block_effect *Effect = (block_effect *)Memory_Block_AddressAtIndex(Memory, F_Effects, Layer->Block_Effect_Index[i]);
        header_effect *EffectHeader = Effect_EntryFromID(State, Effect->ID);
        for (int h = 0; h < EffectHeader->Property_Count; h++) {
            header_property ChannelHeader = State->Property[EffectHeader->PropertyStartIndex + h];
            property_channel *Property = (property_channel *)Memory_Block_AddressAtIndex(Memory, F_Properties, Effect->Block_Property_Index[h]);
            if (Property->Block_Bezier_Count) {
                block_bezier *Bezier = (block_bezier *)Memory_Block_AddressAtIndex(Memory, F_Bezier, Property->Block_Bezier_Index[i], 0);
                History_Action_Block_Swap(Memory, F_Bezier, Bezier);
                Bezier->Occupied = 0;
            }
            History_Action_Block_Swap(Memory, F_Properties, Property);
            Property->Occupied = 0;
        }
        History_Action_Block_Swap(Memory, F_Effects, Effect);
        Effect->Occupied = 0;
    }
    History_Action_Swap(Memory, F_File, sizeof(File->Layer_Count), &File->Layer_Count);
    File->Layer_Count--;
}

static layer_transforms
Layer_GetTransforms(block_layer *Layer) {
    return { Layer->x.CurrentValue, Layer->y.CurrentValue, Layer->ax.CurrentValue, Layer->ay.CurrentValue, Layer->rotation.CurrentValue, Layer->scale.CurrentValue };
}

static int
Layer_GetTopOffset(project_data *File, memory *Memory)
{
    if (File->Layer_Count == 0)
        return 11;
    int TopOffset = 9999;
    int h = 0, c = 0, i = 0;
    while (Block_Loop(Memory, F_Layers, File->Layer_Count, &h, &c, &i)) {
        block_layer *Layer = (block_layer *)Memory_Block_AddressAtIndex(Memory, F_Layers, i);
        if (Layer->Block_Composition_Index == File->PrincipalCompIndex) {
            TopOffset = (Layer->Vertical_Offset < TopOffset) ? Layer->Vertical_Offset : TopOffset;
        }
    }
    return TopOffset;
}


static void
Layer_UpdateMasksEffects(project_state *State, block_layer *Layer, memory *Memory, void *EffectBitmapAddress,
        int Width, int Height, int BytesPerPixel)
{
    uint64 Size = Width*Height*BytesPerPixel;

    // We need two of these: one with multisampling enabled and a
    // non-multisampled one that we can blit to.
    gl_effect_layer TestL = {};
    gl_effect_layer TestM = {};

    GL_UpdateTexture(&TestL, EffectBitmapAddress, Width, Height, BytesPerPixel, 0);
    GL_UpdateTexture(&TestM, EffectBitmapAddress, Width, Height, BytesPerPixel, 1);

    if (Layer->IsShapeLayer) {
        shape_layer *Shape = &Layer->Shape;
        shape_options ShapeOpt = Layer->ShapeOpt;
        void *Data = Memory_PushScratch(Memory, sizeof(nvg_point) * 128);
        Arbitrary_Zero((uint8 *)Data, sizeof(nvg_point) * 128);
        layer_transforms T = Layer_GetTransforms(Layer);
        v2 Min = {}, Max = {};
        uint32 NumberOfVerts = NVG_FlattenPath(Memory, Shape, ShapeOpt, (nvg_point *)Data,
                                               State, T, Shape->Width, Shape->Height, Width, Height, 1, &Min, &Max);
        void *Data_Stroke = Memory_PushScratch(Memory, sizeof(real32) * 4 * 256);
        uint32 StrokeCount = NVG_ExpandStroke(Memory, NumberOfVerts, ShapeOpt.StrokeWidth, ShapeOpt.LineCapType, ShapeOpt.LineJoinType, Shape->IsClosed, (nvg_point *)Data, (real32 *)Data_Stroke);
        void *Data_Fill = Memory_PushScratch(Memory, sizeof(real32) * 4 * NumberOfVerts);
        NVG_ExpandFill(Memory, NumberOfVerts, (nvg_point *)Data, (real32 *)Data_Fill);

        Assert(0);
        // GL_RasterizeShape(&TestL, &TestM, Data_Stroke, Data_Fill, StrokeCount, NumberOfVerts, T,
        //                 Width, Height, BytesPerPixel, EffectBitmapAddress, Shape->Width, Shape->Height,
        //                 Shape->Opt.StrokeCol, Shape->Opt.FillCol, Shape->Opt.Visibility);

        Memory_PopScratch(Memory, sizeof(real32) * 4 * NumberOfVerts);
        Memory_PopScratch(Memory, sizeof(real32) * 4 * 256);
        Memory_PopScratch(Memory, sizeof(nvg_point) * 128);

        // Bitmap_StencilAlpha(SourceBitmapAddress, EffectBitmapAddress, Source->BytesPerPixel, Size);
    }

    for (int i = 0; i < Layer->Block_Effect_Count; i++)
    {
        block_effect Effect = *(block_effect *)Memory_Block_AddressAtIndex(Memory, F_Effects, Layer->Block_Effect_Index[i]);
        header_effect *EffectEntry = Effect_EntryFromID(State, Effect.ID);

        if (Effect.IsToggled) {
            uint64 Size = (sizeof(real32) * MAX_PROPERTIES_PER_EFFECT) + (sizeof(real32) * 10);
            real32 *Data;
            if (EffectEntry->DisplayType == effect_display_type_curves) {
                Data = (real32 *)Memory_PushScratch(Memory, Size);
                uint16 SortedPointIndex[MAX_PROPERTIES_PER_EFFECT];
                v2 *SortedPointValues = (v2 *)(Data + 5);
                for (int c = 0; c < 5; c++) {
                    *(Data + c) = Effect.ExtraData[c];
                    uint32 Shift = MAX_PROPERTIES_PER_EFFECT / 5 * c;
                    uint16 *SortedPointIndexPlayhead = SortedPointIndex + Shift;
                    v2 *SortedPointValuesPlayhead = SortedPointValues + Shift;
                    Effect_Curves_Sort(Memory, &Effect, SortedPointIndexPlayhead, c);
                    for (int a = 0; a < Effect.ExtraData[c]; a++) {
                        *SortedPointValuesPlayhead = Effect_V2(Memory, &Effect, SortedPointIndexPlayhead[a]);
                        SortedPointValuesPlayhead++;
                    }
                }
            } else {
                Data = (real32 *)Memory_PushScratch(Memory, Size);
                for (int c = 0; c < EffectEntry->Property_Count; c++) {
                    property_channel *Property = (property_channel *)Memory_Block_AddressAtIndex(Memory, F_Properties, Effect.Block_Property_Index[c]);
                    Data[c] = Property->CurrentValue;
                }
            }
            EffectEntry->func(Data, Width, Height, BytesPerPixel, EffectBitmapAddress, EffectEntry->GLShaderIndex);
            Memory_PopScratch(Memory, Size);
        }
    }

    GL_DeleteHWBuffer(&TestL);
    GL_DeleteHWBuffer(&TestM);
}

static void
Layer_ToggleChannel(project_data *File, memory *Memory, int32 a)
{
    int h = 0, c = 0, i = 0;
    while (Block_Loop(Memory, F_Layers, File->Layer_Count, &h, &c, &i))
    {
        block_layer *Layer = (block_layer *)Memory_Block_AddressAtIndex(Memory, F_Layers, i);
        if (Layer->IsSelected & 0x01)
            Layer->Property[a].IsToggled ^= 1;
    }
}

static void
Layer_Select(memory *Memory, project_state *State, int32 i)
{
    block_layer *Layer = (block_layer *)Memory_Block_AddressAtIndex(Memory, F_Layers, i);
    // Assert(!(Layer->IsSelected & 0x02));
    Layer->IsSelected |= 0x01;
    State->MostRecentlySelectedLayer = i;
    State->Interact_Transform = {};
    State->RecentSelectionType = selection_type_layer;
}

static void
Layer_Select_RecurseUp(memory *Memory, project_state *State, int32 i, int16 RecursionIdx[MAX_PRECOMP_RECURSIONS], uint32 Recursions)
{
    for (int a = 1; a <= Recursions; a++) {
        block_layer *Layer = (block_layer *)Memory_Block_AddressAtIndex(Memory, F_Layers, RecursionIdx[a]);
        Layer->IsSelected = 0x02;
    }
}

static void
Interact_BoxSelect_Start(project_data *File, project_state *State, memory *Memory) {
    int h = 0, c = 0, i = 0;
    while (Block_Loop(Memory, F_Layers, File->Layer_Count, &h, &c, &i)) {
        block_layer *Layer = (block_layer *)Memory_Block_AddressAtIndex(Memory, F_Layers, i);
        if (Layer->IsSelected & 0x01) {
            Layer->IsSelected |= 0x04;
        }
    }
}

static void
Interact_BoxSelect_End(project_data *File, project_state *State, memory *Memory) {
    int h = 0, c = 0, i = 0;
    while (Block_Loop(Memory, F_Layers, File->Layer_Count, &h, &c, &i)) {
        block_layer *Layer = (block_layer *)Memory_Block_AddressAtIndex(Memory, F_Layers, i);
        if (Layer->IsSelected & 0x04) {
            Layer->IsSelected ^= 0x04;
        }
    }
}

static void
Layer_DeselectAll(project_data *File, project_state *State, memory *Memory, bool32 AllowComp) {
    int h = 0, c = 0, i = 0;
    bool32 ShiftLayers = false;
    while (Block_Loop(Memory, F_Layers, File->Layer_Count, &h, &c, &i)) {
        block_layer *Layer = (block_layer *)Memory_Block_AddressAtIndex(Memory, F_Layers, i);
        if (Layer->IsSelected & 0x04) {
            ShiftLayers = 1;
        } else {
            if (!(AllowComp && Layer->IsSelected & 0x02)) {
                Layer->IsSelected = 0x00;
            }
        }
    }
    State->Interact_Transform = {};
    if (!ShiftLayers) {
        State->MostRecentlySelectedLayer = -1;
    }
}

// TODO(fox): This function will be replaced once properties are reworked.
// h: index of the total amount of properties and effects
// c: index of the amount of properties in a given effect
// p: prior property's keyframe count, so we can increment the sorted keyframe array properly
static bool32
Layer_LoopChannels(project_state *State, memory *Memory, sorted_property_array **SortedProperty, uint16 **SortedKeyframe, block_layer *Layer,
                   property_channel **Property, block_effect **EffectOut, int *h, int *c, int *p, int LoopNumber)
{
    uint32 Amount = LoopNumber + Layer->Block_Effect_Count;
    // Assert(Layer->Block_Effect_Count < 2);
    while (*h < Amount) {
        if (*h < LoopNumber && *c == 0) {
            *Property = &Layer->Property[*h];
            if (*h != 0) {
                *SortedProperty += 1;
                *SortedKeyframe += *p;
            }
            *h += 1;
            *p = (**Property).Keyframe_Count;
            return 1;
        } else {
            uint16 EffectIdx = Layer->Block_Effect_Index[*h - AmountOf(Layer->Property)];
            block_effect *Effect = (block_effect *)Memory_Block_AddressAtIndex(Memory, F_Effects, EffectIdx);
            if (EffectOut)
                *EffectOut = Effect;
            header_effect *EffectHeader = Effect_EntryFromID(State, Effect->ID);
            while (*c < EffectHeader->Property_Count) {
                // header_property ChannelHeader = State->Property[EffectHeader->PropertyStartIndex + c];
                *Property = (property_channel *)Memory_Block_AddressAtIndex(Memory, F_Properties, Effect->Block_Property_Index[*c]);
                *SortedProperty += 1;
                *SortedKeyframe += *p;
                *p = (**Property).Keyframe_Count;
                *c += 1;
                return 1;
            }
            *h += 1;
            *c = 0;
        }
    }
    Assert(*h != (Amount - 1));
    return 0;
}

static void
Layer_ToggleAllChannels(project_state *State, memory *Memory, block_layer *Layer,
                        sorted_comp_array *SortedCompStart, sorted_layer_array *SortedLayerStart,
                        sorted_property_array *SortedPropertyStart, uint16 *SortedKeyframeArray)
{
    bool32 ToggleMode = 1;
    {
        sorted_property_array *InfoLocation = SortedPropertyStart + SortedLayerStart->SortedPropertyStart;
        uint16 *ArrayLocation = SortedKeyframeArray + SortedLayerStart->SortedKeyframeStart;
        int h = 0, c = 0, p = 0;
        property_channel *Property = NULL;
        block_effect *Effect = NULL;
        while (Layer_LoopChannels(State, Memory, &InfoLocation, &ArrayLocation, Layer, &Property, &Effect, &h, &c, &p))
        {
            if (Property->IsToggled) {
                ToggleMode = 0;
                break;
            }
        }
    }
    sorted_property_array *InfoLocation = SortedPropertyStart + SortedLayerStart->SortedPropertyStart;
    uint16 *ArrayLocation = SortedKeyframeArray + SortedLayerStart->SortedKeyframeStart;
    int h = 0, c = 0, p = 0;
    property_channel *Property = NULL;
    block_effect *Effect = NULL;
    while (Layer_LoopChannels(State, Memory, &InfoLocation, &ArrayLocation, Layer, &Property, &Effect, &h, &c, &p))
    {
        if (Property->Keyframe_Count) {
            Property->IsToggled = ToggleMode;
        }
    }
}

static void
Layer_Select_Traverse(uint16 PrincipalCompIndex, memory *Memory, project_state *State, int32 IndexToFind, sorted_comp_array *SortedCompArray, sorted_layer_array *SortedLayerArray,
                      int16 RecursionIdx[MAX_PRECOMP_RECURSIONS], int32 *Recursions)
{
    uint16 CompIndex = 0;
    if (RecursionIdx[*Recursions] == -1) {
        CompIndex = PrincipalCompIndex;
    } else {
        block_layer *Layer = (block_layer *)Memory_Block_AddressAtIndex(Memory, F_Layers, RecursionIdx[*Recursions]);
        CompIndex = Layer->Block_Source_Index;
    }
    sorted_layer_array *SortedLayerStart = Sorted_GetLayerStart(SortedLayerArray, SortedCompArray, CompIndex);
    sorted_comp_array SortedCompStart = SortedCompArray[CompIndex];
    uint32 RecursionsCurrent = *Recursions;
    for (int i = SortedCompStart.LayerCount - 1; i >= 0; i--)
    {
        sorted_layer_array SortEntry = SortedLayerStart[i];
        uint32 Index_Physical = SortEntry.Block_Layer_Index;
        block_layer *Layer = (block_layer *)Memory_Block_AddressAtIndex(Memory, F_Layers, Index_Physical);
        if (Layer->IsPrecomp && (Layer->IsSelected & 0x02)) {
            *Recursions = RecursionsCurrent + 1;
            RecursionIdx[*Recursions] = Index_Physical;
            Layer_Select_Traverse(PrincipalCompIndex, Memory, State, IndexToFind, SortedCompArray, SortedLayerArray, RecursionIdx, Recursions);
        } else if (Index_Physical == IndexToFind) {
            return;
        }
    }
}

static void
Layer_GetDimensions(memory *Memory, block_layer *Layer, int *Width, int *Height)
{
    if (Layer->IsPrecomp) {
        block_composition *Comp = (block_composition *)Memory_Block_AddressAtIndex(Memory, F_Precomps, Layer->Block_Source_Index);
        *Width = Comp->Width;
        *Height = Comp->Height;
    } else if (Layer->IsShapeLayer) {
        *Width = Layer->Shape.Width;
        *Height = Layer->Shape.Height;
    } else {
        block_source *Source = (block_source *)Memory_Block_AddressAtIndex(Memory, F_Sources, Layer->Block_Source_Index);
        *Width = Source->Width;
        *Height = Source->Height;
    }
}

static v2
Layer_TraverseForPoint(project_data *File, project_state *State, memory *Memory, v2 PrincipalCompUV, sorted_comp_array *SortedCompArray, sorted_layer_array *SortedLayerArray, uint16 LayerIndex)
{
    int16 RecursionIdx[MAX_PRECOMP_RECURSIONS] = {};
    RecursionIdx[0] = -1;
    int32 Recursions = 0;
    sorted_layer_array *SortedLayerStart = Sorted_GetLayerStart(SortedLayerArray, SortedCompArray, File->PrincipalCompIndex);
    sorted_comp_array SortedCompStart = SortedCompArray[File->PrincipalCompIndex];
    block_composition *Comp = (block_composition *)Memory_Block_AddressAtIndex(Memory, F_Precomps, File->PrincipalCompIndex);
    Layer_Select_Traverse(File->PrincipalCompIndex, Memory, State, LayerIndex, SortedCompArray, SortedLayerArray, RecursionIdx, &Recursions);
    v2 PointUV = {0, 0};
    int OuterWidth = Comp->Width, OuterHeight = Comp->Height;
    int InnerWidth = 0, InnerHeight = 0;
    if (Recursions == 0) {
        block_layer *Layer = (block_layer *)Memory_Block_AddressAtIndex(Memory, F_Layers, LayerIndex);
        layer_transforms T = Layer_GetTransforms(Layer);
        Layer_GetDimensions(Memory, Layer, &InnerWidth, &InnerHeight);
        PointUV = T_CompUVToLayerUV(T, OuterWidth, OuterHeight, InnerWidth, InnerHeight, PrincipalCompUV);
    } else {
        for (int i = 1; i <= Recursions; i++) {
            block_layer *InnerLayer = (block_layer *)Memory_Block_AddressAtIndex(Memory, F_Layers, RecursionIdx[i]);
            layer_transforms T = Layer_GetTransforms(InnerLayer);
            Layer_GetDimensions(Memory, InnerLayer, &InnerWidth, &InnerHeight);
            PointUV = T_CompUVToLayerUV(T, OuterWidth, OuterHeight, InnerWidth, InnerHeight, PrincipalCompUV);
            OuterWidth = InnerWidth;
            OuterHeight = InnerHeight;
        }
    }
    return PointUV * V2(InnerWidth, InnerHeight);
}

// TODO(fox): Precomps?
static bool32
Layer_TestForPoint(memory *Memory, project_state *State, ui *UI, sorted_comp_array *SortedCompArray, sorted_layer_array *SortedLayerArray, uint16 CompIndex, v2 CompUV)
{
    block_composition *Comp = (block_composition *)Memory_Block_AddressAtIndex(Memory, F_Precomps, CompIndex);
    sorted_comp_array SortedCompStart = SortedCompArray[CompIndex];
    sorted_layer_array *SortedLayerStart = Sorted_GetLayerStart(SortedLayerArray, SortedCompArray, CompIndex);
    for (int i = SortedCompStart.LayerCount - 1; i >= 0; i--) {
        sorted_layer_array SortEntry = SortedLayerStart[i];
        uint32 Index_Physical = SortEntry.Block_Layer_Index;
        block_layer *Layer = (block_layer *)Memory_Block_AddressAtIndex(Memory, F_Layers, Index_Physical);
        int Width, Height;
        Layer_GetDimensions(Memory, Layer, &Width, &Height);
        layer_transforms T = Layer_GetTransforms(Layer);
        v2 UV = T_CompUVToLayerUV(T, Comp->Width, Comp->Height, Width, Height, CompUV);
        if (UV.x <= 1.0f && UV.x >= 0.0f && UV.y <= 1.0f && UV.y >= 0.0f && ((Layer->IsSelected & 0x01) || Layer->IsPrecomp) && !Layer->IsLocked)
        {
            return 1;
        }
    }
    return 0;
}

// Same loop as Render_UI and ImGui_Viewport_SelectedLayerUI except we're
// NOTE(fox): We loop twice to allow for convenient down-travelling when only
// one layer is selected, toggleable by the BelowOnly bool (i.e. shift held).
#if 0
static int32
Layer_TestSelection(memory *Memory, project_state *State, ui *UI, sorted_comp_array *SortedCompArray, sorted_layer_array *SortedLayerArray, uint16 CompIndex, bool32 BelowOnly)
{
    block_composition *Comp = (block_composition *)Memory_Block_AddressAtIndex(Memory, F_Precomps, CompIndex);
    sorted_comp_array SortedCompStart = SortedCompArray[CompIndex];
    sorted_layer_array *SortedLayerStart = Sorted_GetLayerStart(SortedLayerArray, SortedCompArray, CompIndex);
    int SelectionCount = 0;
    int SelectedLayerIndex = 0;
    for (int i = SortedCompStart.LayerCount - 1; i >= 0; i--) {
        sorted_layer_array SortEntry = SortedLayerStart[i];
        uint32 Index_Physical = SortEntry.Block_Layer_Index;
        block_layer *Layer = (block_layer *)Memory_Block_AddressAtIndex(Memory, F_Layers, Index_Physical);
        int Width, Height;
        Layer_GetDimensions(Memory, Layer, &Width, &Height);
        layer_transforms T = Layer_GetTransforms(Layer);
        v2 UV = T_CompUVToLayerUV(T, Comp->Width, Comp->Height, Width, Height, State->LastClickedPoint);
        if (UV.x <= 1.0f && UV.x >= 0.0f && UV.y <= 1.0f && UV.y >= 0.0f && Layer->IsSelected)
        {
            SelectionCount++;
            SelectedLayerIndex = i;
        }
    }
    int32 LayerIndex = -1;
    for (int i = SortedCompStart.LayerCount - 1; i >= 0; i--) {
        sorted_layer_array SortEntry = SortedLayerStart[i];
        uint32 Index_Physical = SortEntry.Block_Layer_Index;
        block_layer *Layer = (block_layer *)Memory_Block_AddressAtIndex(Memory, F_Layers, Index_Physical);
        int Width, Height;
        Layer_GetDimensions(Memory, Layer, &Width, &Height);
        layer_transforms T = Layer_GetTransforms(Layer);
        v2 UV = T_CompUVToLayerUV(T, Comp->Width, Comp->Height, Width, Height, State->LastClickedPoint);
        if (UV.x <= 1.0f && UV.x >= 0.0f && UV.y <= 1.0f && UV.y >= 0.0f && (!Layer->IsSelected || (Layer->IsPrecomp && Layer->IsSelected)) && !Layer->IsLocked)
        {
            if (Layer->IsPrecomp) {
                layer_transforms T = Layer_GetTransforms(Layer);
                if (ExtraT.scale != 0) {
                    T = Transform_Add(T, ExtraT, Comp->Width, Comp->Height);
                }
                T = Transform_TestInteracts(State, Layer, SortEntry, T);
                LayerIndex = Layer_TestSelection(Memory, State, UI, SortedCompArray, SortedLayerArray, Layer->Block_Source_Index, BelowOnly);
                if (LayerIndex != -1)
                    break;
            } else {
                if (!BelowOnly && SelectionCount == 1) {
                    if (i < SelectedLayerIndex) {
                        LayerIndex = Index_Physical;
                        break;
                    }
                } else {
                    LayerIndex = Index_Physical;
                    break;
                }
            }
        }
        // if (Layer->IsPrecomp) {
        //     Layer_RecursiveDeselect(Memory, SortedCompArray, SortedLayerArray, TargetIndex, Layer->Block_Source_Index);
        // }
        // if (Layer->Block_Composition_Index != TargetIndex) {
        //     Layer->IsSelected = false;
        // }
    }
    return LayerIndex;
}
#endif

// TODO(fox): learn this; stop stealing from stackoverflow
bool32 Line_TestIntersect(real32 p0_x, real32 p0_y, real32 p1_x, real32 p1_y, 
                          real32 p2_x, real32 p2_y, real32 p3_x, real32 p3_y)
{
    real32 s1_x, s1_y, s2_x, s2_y;

    s1_x = p1_x - p0_x;
    s1_y = p1_y - p0_y;
    s2_x = p3_x - p2_x;
    s2_y = p3_y - p2_y;

    real32 b = (-s2_x * s1_y + s1_x * s2_y);
    if (b == 0)
        return 0;

    real32 s, t;
    s = (-s1_y * (p0_x - p2_x) + s1_x * (p0_y - p2_y)) / b;
    t = ( s2_x * (p0_y - p2_y) - s2_y * (p0_x - p2_x)) / b;

    if (s >= 0 && s <= 1) {
        int a = 0;
    }

    if (s >= 0 && s <= 1 && t >= 0 && t <= 1)
    {
        return 1;
    }
    return 0; // No collision
}

static bool32
Transform_TestBox(block_layer *Layer, uint32 Width, uint32 Height, v2 Min, v2 Max)
{
    real32 Rad = (Layer->rotation.CurrentValue * (PI / 180));
    real32 s = Layer->scale.CurrentValue;

    v2 XAxis = (Width * s)*V2(cos(Rad), sin(Rad));
    v2 YAxis = (Height * -s)*V2(sin(Rad), -cos(Rad));

    real32 AnchorX = Layer->ax.CurrentValue;
    real32 AnchorY = Layer->ay.CurrentValue;

    v2 Pos = {Layer->x.CurrentValue, Layer->y.CurrentValue};
    v2 Origin = Pos - (XAxis * AnchorX) - (YAxis * AnchorY);

    if (Origin.x > Min.x && Origin.x < Max.x && 
        Origin.y > Min.y && Origin.y < Max.y)
        return true;

    real32 XLengthSq = 1.0f / LengthSq(XAxis);
    real32 YLengthSq = 1.0f / LengthSq(YAxis);

    v2 Box[4] = { Min, V2(Min.x, Max.y), Max, V2(Max.x, Min.y) };
    v2 Point[4] = {Origin, Origin + YAxis, Origin + XAxis + YAxis, Origin + XAxis };
    if (Length((Max - Min)) < 2.0f)
        return false;
    v2 *P1_B = &Box[3];
    v2 *P2_B = &Box[0];
    for (int x = 0; x < 4; x++) {
        v2 *P1 = &Point[3];
        v2 *P2 = &Point[0];
        for (int i = 0; i < 4; i++) {
            if (Line_TestIntersect(P1->x, P1->y, P2->x, P2->y, P1_B->x, P1_B->y, P2_B->x, P2_B->y))
                return true;
            P1 = P2++;
        }
        P1_B = P2_B++;
    }
    return false;
}

// TODO(fox): It would probably be faster to transform the box into layer space
// and test that way. Don't know how to do the UV test though.

static bool32
Shape_TestBoxSelect(layer_transforms T, uint32 CompWidth, uint32 CompHeight, uint32 ShapeWidth, uint32 ShapeHeight, v2 Box[4], 
                    nvg_point *Point, uint16 PointCount)
{
    // v2 BoxLocal[4] = {};
    // for (int x = 0; x < 4; x++) {
    //     BoxLocal[x] = T_CompPosToLayerPos(T, CompWidth, CompHeight, ShapeHeight, ShapeWidth, Box[x].x, Box[x].y);
    // }
    Assert(Box[0].x < Box[2].x && Box[0].y < Box[2].y);
#if 1
    for (int i = 0; i < PointCount; i++) {
        nvg_point *P0 = &Point[i];
        v2 Pos0 = TransformPoint(T, ShapeWidth, ShapeHeight, V2(P0->x, P0->y));
        if (Pos0.x > Box[0].x && Pos0.x < Box[2].x && 
            Pos0.y > Box[0].y && Pos0.y < Box[2].y)
            return true;
        P0->x = Pos0.x;
        P0->y = Pos0.y;
    }
#endif
#if 1
    nvg_point *P0 = &Point[PointCount-1];
    nvg_point *P1 = &Point[0];
    for (int i = 0; i < PointCount; i++) {
        if (Line_TestIntersect(P0->x, P0->y, P1->x, P1->y, Box[0].x, Box[0].y, Box[1].x, Box[1].y))
            return true;
        if (Line_TestIntersect(P0->x, P0->y, P1->x, P1->y, Box[1].x, Box[1].y, Box[2].x, Box[2].y))
            return true;
        if (Line_TestIntersect(P0->x, P0->y, P1->x, P1->y, Box[2].x, Box[2].y, Box[3].x, Box[3].y))
            return true;
        if (Line_TestIntersect(P0->x, P0->y, P1->x, P1->y, Box[3].x, Box[3].y, Box[0].x, Box[0].y))
            return true;
        P0 = P1++;
    }
#endif
    return false;
}

static void
Layer_TestBoxSelect(memory *Memory, project_state *State, ui *UI, sorted_comp_array *SortedCompArray, sorted_layer_array *SortedLayerArray, 
                    uint16 PrincipalIndex, layer_transforms ExtraT, v2 MinPos, v2 MaxPos)
{
    block_composition *Comp = (block_composition *)Memory_Block_AddressAtIndex(Memory, F_Precomps, PrincipalIndex);
    sorted_comp_array SortedCompStart = SortedCompArray[PrincipalIndex];
    sorted_layer_array *SortedLayerStart = Sorted_GetLayerStart(SortedLayerArray, SortedCompArray, PrincipalIndex);
    for (int i = SortedCompStart.LayerCount - 1; i >= 0; i--) {
        sorted_layer_array SortEntry = SortedLayerStart[i];
        uint32 Index_Physical = SortEntry.Block_Layer_Index;
        block_layer *Layer = (block_layer *)Memory_Block_AddressAtIndex(Memory, F_Layers, Index_Physical);
        if (Layer->IsLocked)
            continue;
        if (Layer->IsShapeLayer) {
            shape_layer *Shape = &Layer->Shape;
            int Width = Shape->Width, Height = Shape->Height;
            layer_transforms T = Layer_GetTransforms(Layer);

            nvg_point *NVGPointData = (nvg_point *)Memory_PushScratch(Memory, sizeof(nvg_point) * 1024);
            v2 ShapeMin = {}, ShapeMax = {};
            uint32 NumberOfVerts = NVG_FlattenPath(Memory, Shape, Layer->ShapeOpt, NVGPointData,
                                                   State, T, Shape->Width, Shape->Height, Comp->Width, Comp->Height, 1, &ShapeMin, &ShapeMax);
            v2 Box[4] = { MinPos, V2(MinPos.x, MaxPos.y), MaxPos, V2(MaxPos.x, MinPos.y) };
            if (Shape_TestBoxSelect(T, Comp->Width, Comp->Height, Shape->Width, Shape->Height, Box, NVGPointData, NumberOfVerts)) {
                Layer_Select(Memory, State, Index_Physical);
            }

            Memory_PopScratch(Memory, sizeof(nvg_point) * 1024);
        } else if (Layer->IsPrecomp && (Layer->IsSelected & 0x02)) {
            int Width = 0, Height = 0;
            Layer_GetDimensions(Memory, Layer, &Width, &Height);
            // only like 20% sure how this works...
            layer_transforms NewExtraT = Layer_GetTransforms(Layer);
            v2 NewMinPos = T_CompPosToLayerPos(NewExtraT, Comp->Width, Comp->Height, Width, Height, MinPos.x, MinPos.y);
            v2 NewMaxPos = T_CompPosToLayerPos(NewExtraT, Comp->Width, Comp->Height, Width, Height, MaxPos.x, MaxPos.y);
            NewExtraT.rotation = ExtraT.rotation - NewExtraT.rotation;
            NewExtraT.scale = ExtraT.scale / NewExtraT.scale;
            Layer_TestBoxSelect(Memory, State, UI, SortedCompArray, SortedLayerArray, 
                                Layer->Block_Source_Index, NewExtraT, NewMinPos, NewMaxPos);
        } else {
            int Width, Height;
            Layer_GetDimensions(Memory, Layer, &Width, &Height);
            if (Transform_TestBox(Layer, Width, Height, MinPos, MaxPos))
                Layer_Select(Memory, State, Index_Physical);
        }
    }
}

static void
Layer_RecursiveDeselect(memory *Memory, sorted_comp_array *SortedCompArray, sorted_layer_array *SortedLayerArray, uint16 TargetIndex, uint16 PrincipalIndex)
{
    block_composition *Comp = (block_composition *)Memory_Block_AddressAtIndex(Memory, F_Precomps, PrincipalIndex);
    sorted_comp_array SortedCompStart = SortedCompArray[PrincipalIndex];
    sorted_layer_array *SortedLayerStart = Sorted_GetLayerStart(SortedLayerArray, SortedCompArray, PrincipalIndex);
    for (int i = 0; i < SortedCompStart.LayerCount; i++) {
        sorted_layer_array SortEntry = SortedLayerStart[i];
        uint32 Index_Physical = SortEntry.Block_Layer_Index;
        block_layer *Layer = (block_layer *)Memory_Block_AddressAtIndex(Memory, F_Layers, Index_Physical);
        if (Layer->IsPrecomp) {
            Layer_RecursiveDeselect(Memory, SortedCompArray, SortedLayerArray, TargetIndex, Layer->Block_Source_Index);
        }
        if (Layer->Block_Composition_Index != TargetIndex) {
            Layer->IsSelected = 0x00;
        }
    }
}