// Fill out your copyright notice in the Description page of Project Settings.


#include "Thumbnail/BagConfigThumbnailRenderer.h"

#include "CanvasItem.h"
#include "CanvasTypes.h"
#include "ProjectFish/DataAsset/BagConfigAsset.h"
#include "ProjectFish/DataAsset/ShapeAsset.h"

bool UBagConfigThumbnailRenderer::CanVisualizeAsset(UObject* Object)
{
	return Cast<UBagConfigAsset>(Object) != nullptr;
}

void UBagConfigThumbnailRenderer::Draw(UObject* Object, int32 X, int32 Y, uint32 Width, uint32 Height,
	FRenderTarget* RenderTarget, FCanvas* Canvas, bool bAdditionalViewFamily)
{
	UBagConfigAsset* BagConfig= Cast<UBagConfigAsset>(Object);
	if (!BagConfig || !Canvas)
	{
		return;
	}

	DrawBag(BagConfig, Canvas, X, Y, Width, Height);
}

void UBagConfigThumbnailRenderer::DrawBag(UBagConfigAsset* BagConfig, FCanvas* Canvas, int32 X, int32 Y,
	uint32 Width, uint32 Height)
{
	 if (!BagConfig || !Canvas)
    {
        return;
    }

    // 检查是否有背包形状资源
    if (!BagConfig->BagShapeAsset)
    {
        // 绘制错误状态
        FCanvasBoxItem ErrorBox(FVector2D(X, Y), FVector2D(Width, Height));
        ErrorBox.SetColor(FLinearColor(0.5f, 0.1f, 0.1f, 1.0f));
        Canvas->DrawItem(ErrorBox);
        return;
    }

    UShapeAsset* BagShapeAsset = BagConfig->BagShapeAsset;

    // Clear the background
    FCanvasBoxItem BackgroundBox(FVector2D(X, Y), FVector2D(Width, Height));
    BackgroundBox.SetColor(FLinearColor(0.1f, 0.1f, 0.1f, 1.0f));
    Canvas->DrawItem(BackgroundBox);

    // Calculate the best fit scale with spacing for separators
    float SeparatorWidth = 2.0f; // White separator width
    float Scale = GetBestFitScale(BagShapeAsset->ShapeWidth, BagShapeAsset->ShapeHeight, Width, Height);
    float CellSize = Scale - SeparatorWidth; // Reduce cell size to make room for separators

    // Calculate starting position to center the grid (including separators)
    float GridWidth = BagShapeAsset->ShapeWidth * Scale - SeparatorWidth;
    float GridHeight = BagShapeAsset->ShapeHeight * Scale - SeparatorWidth;
    float StartX = X + (Width - GridWidth) * 0.5f;
    float StartY = Y + (Height - GridHeight) * 0.5f;

    // Draw the bag slots (background) with separators
    for (int32 GridY = 0; GridY < BagShapeAsset->ShapeHeight; GridY++)
    {
        for (int32 GridX = 0; GridX < BagShapeAsset->ShapeWidth; GridX++)
        {
            float CellStartX = StartX + GridX * Scale;
            float CellStartY = StartY + GridY * Scale;

            bool bIsActive = BagShapeAsset->IsSlotActive(GridX, GridY);

            // Draw filled cell (smaller to leave space for separators)
            FCanvasTileItem CellTile(FVector2D(CellStartX, CellStartY), FVector2D(CellSize, CellSize), 
                bIsActive ? FLinearColor(0.3f, 0.3f, 0.3f, 1.0f) : FLinearColor(0.15f, 0.15f, 0.15f, 1.0f));
            CellTile.BlendMode = SE_BLEND_Opaque;
            Canvas->DrawItem(CellTile);
        }
    }
    
    // Draw white separators
    // Vertical separators
    for (int32 GridX = 1; GridX < BagShapeAsset->ShapeWidth; GridX++)
    {
        float SeparatorX = StartX + GridX * Scale - SeparatorWidth;
        FCanvasTileItem VerticalSeparator(FVector2D(SeparatorX, StartY), FVector2D(SeparatorWidth, GridHeight), FLinearColor::White);
        VerticalSeparator.BlendMode = SE_BLEND_Opaque;
        Canvas->DrawItem(VerticalSeparator);
    }
    
    // Horizontal separators
    for (int32 GridY = 1; GridY < BagShapeAsset->ShapeHeight; GridY++)
    {
        float SeparatorY = StartY + GridY * Scale - SeparatorWidth;
        FCanvasTileItem HorizontalSeparator(FVector2D(StartX, SeparatorY), FVector2D(GridWidth, SeparatorWidth), FLinearColor::White);
        HorizontalSeparator.BlendMode = SE_BLEND_Opaque;
        Canvas->DrawItem(HorizontalSeparator);
    }

    // Draw skills on top
    for (const FPlacedSkillInfo& PlacedSkill : BagConfig->PlacedSkills)
    {
        DrawSkill(PlacedSkill, Canvas, StartX, StartY, Scale, SeparatorWidth);
    }

    // Draw outer border
    FCanvasBoxItem OuterBorder(FVector2D(StartX, StartY), FVector2D(GridWidth, GridHeight));
    OuterBorder.SetColor(FLinearColor::White);
    OuterBorder.LineThickness = 3.0f;
    Canvas->DrawItem(OuterBorder);
}

float UBagConfigThumbnailRenderer::GetBestFitScale(int32 ShapeWidth, int32 ShapeHeight, uint32 CanvasWidth,
    uint32 CanvasHeight) const
{
    if (ShapeWidth == 0 || ShapeHeight == 0)
    {
        return 1.0f;
    }

    // Leave some padding
    float PaddedWidth = CanvasWidth * 0.85f;
    float PaddedHeight = CanvasHeight * 0.85f;

    float ScaleX = PaddedWidth / ShapeWidth;
    float ScaleY = PaddedHeight / ShapeHeight;

    // Use the smaller scale to ensure everything fits
    float Scale = FMath::Min(ScaleX, ScaleY);
    
    // Ensure minimum cell size for visibility
    Scale = FMath::Max(Scale, 3.0f);

    return Scale;
}

void UBagConfigThumbnailRenderer::DrawSkill(const struct FPlacedSkillInfo& PlacedSkill, FCanvas* Canvas, float StartX,
                                            float StartY, float Scale, float SeparatorWidth)
{
    if (!PlacedSkill.SkillAsset)
    {
        return;
    }
    
    USkillAsset* SkillObject = PlacedSkill.SkillAsset;
    float CellSize = Scale - SeparatorWidth;
    
    float SkillStartX = StartX + PlacedSkill.PositionX * Scale;
    float SkillStartY = StartY + PlacedSkill.PositionY * Scale;
    
    float SkillWidth = GetSkillSizeValue(SkillObject->SkillSize).X * Scale - SeparatorWidth;
    float SkillHeight = GetSkillSizeValue(SkillObject->SkillSize).Y * Scale - SeparatorWidth;

    // Draw skill background
    FCanvasTileItem SkillTile(FVector2D(SkillStartX, SkillStartY), FVector2D(SkillWidth, SkillHeight), FLinearColor::Blue);
    SkillTile.BlendMode = SE_BLEND_Opaque;
    Canvas->DrawItem(SkillTile);

    // Draw skill border
    FCanvasBoxItem SkillBorder(FVector2D(SkillStartX, SkillStartY), FVector2D(SkillWidth, SkillHeight));
    SkillBorder.SetColor(FLinearColor::White);
    SkillBorder.LineThickness = 2.0f;
    Canvas->DrawItem(SkillBorder);

    // Draw skill name (if there's enough space)
    if (CellSize >= 12.0f && !SkillObject->SkillName.ToString().IsEmpty())
    {
        FString DisplayName = SkillObject->SkillName.ToString();
        if (DisplayName.Len() > 8)
        {
            DisplayName = DisplayName.Left(6) + TEXT("..");
        }

        FCanvasTextItem TextItem(FVector2D(SkillStartX + 2, SkillStartY + 2), FText::FromString(DisplayName), GEngine->GetSmallFont(), FLinearColor::White);
        TextItem.Scale = FVector2D(0.7f, 0.7f);
        Canvas->DrawItem(TextItem);
    }
}