/*
 * Decompiled with CFR 0.152.
 * 
 * Could not load the following classes:
 *  org.jspecify.annotations.Nullable
 */
package net.minecraft.client.renderer;

import java.util.Objects;
import net.minecraft.client.Minecraft;
import net.minecraft.client.renderer.LevelRenderer;
import net.minecraft.client.renderer.chunk.SectionRenderDispatcher;
import net.minecraft.core.BlockPos;
import net.minecraft.core.SectionPos;
import net.minecraft.world.level.Level;
import net.minecraft.world.level.LevelHeightAccessor;
import org.jspecify.annotations.Nullable;

public class ViewArea {
    protected final LevelRenderer levelRenderer;
    protected final Level level;
    protected int sectionGridSizeY;
    protected int sectionGridSizeX;
    protected int sectionGridSizeZ;
    private int viewDistance;
    private SectionPos cameraSectionPos;
    public SectionRenderDispatcher.RenderSection[] sections;

    public ViewArea(SectionRenderDispatcher sectionRenderDispatcher, Level level, int renderDistance, LevelRenderer levelRenderer) {
        this.levelRenderer = levelRenderer;
        this.level = level;
        this.setViewDistance(renderDistance);
        this.createSections(sectionRenderDispatcher);
        this.cameraSectionPos = SectionPos.of(this.viewDistance + 1, 0, this.viewDistance + 1);
    }

    protected void createSections(SectionRenderDispatcher sectionRenderDispatcher) {
        if (!Minecraft.getInstance().isSameThread()) {
            throw new IllegalStateException("createSections called from wrong thread: " + Thread.currentThread().getName());
        }
        int totalSections = this.sectionGridSizeX * this.sectionGridSizeY * this.sectionGridSizeZ;
        this.sections = new SectionRenderDispatcher.RenderSection[totalSections];
        for (int x = 0; x < this.sectionGridSizeX; ++x) {
            for (int y = 0; y < this.sectionGridSizeY; ++y) {
                for (int z = 0; z < this.sectionGridSizeZ; ++z) {
                    int index = this.getSectionIndex(x, y, z);
                    SectionRenderDispatcher sectionRenderDispatcher2 = sectionRenderDispatcher;
                    Objects.requireNonNull(sectionRenderDispatcher2);
                    this.sections[index] = new SectionRenderDispatcher.RenderSection(sectionRenderDispatcher2, index, SectionPos.asLong(x, y + this.level.getMinSectionY(), z));
                }
            }
        }
    }

    public void releaseAllBuffers() {
        for (SectionRenderDispatcher.RenderSection section : this.sections) {
            section.reset();
        }
    }

    private int getSectionIndex(int x, int y, int z) {
        return (z * this.sectionGridSizeY + y) * this.sectionGridSizeX + x;
    }

    protected void setViewDistance(int renderDistance) {
        int dist;
        this.sectionGridSizeX = dist = renderDistance * 2 + 1;
        this.sectionGridSizeY = this.level.getSectionsCount();
        this.sectionGridSizeZ = dist;
        this.viewDistance = renderDistance;
    }

    public int getViewDistance() {
        return this.viewDistance;
    }

    public LevelHeightAccessor getLevelHeightAccessor() {
        return this.level;
    }

    public void repositionCamera(SectionPos cameraSectionPos) {
        for (int gridX = 0; gridX < this.sectionGridSizeX; ++gridX) {
            int lowestX = cameraSectionPos.x() - this.viewDistance;
            int newSectionX = lowestX + Math.floorMod(gridX - lowestX, this.sectionGridSizeX);
            for (int gridZ = 0; gridZ < this.sectionGridSizeZ; ++gridZ) {
                int lowestZ = cameraSectionPos.z() - this.viewDistance;
                int newSectionZ = lowestZ + Math.floorMod(gridZ - lowestZ, this.sectionGridSizeZ);
                for (int gridY = 0; gridY < this.sectionGridSizeY; ++gridY) {
                    int newSectionY = this.level.getMinSectionY() + gridY;
                    SectionRenderDispatcher.RenderSection section = this.sections[this.getSectionIndex(gridX, gridY, gridZ)];
                    long sectionNode = section.getSectionNode();
                    if (sectionNode == SectionPos.asLong(newSectionX, newSectionY, newSectionZ)) continue;
                    section.setSectionNode(SectionPos.asLong(newSectionX, newSectionY, newSectionZ));
                }
            }
        }
        this.cameraSectionPos = cameraSectionPos;
        this.levelRenderer.getSectionOcclusionGraph().invalidate();
    }

    public SectionPos getCameraSectionPos() {
        return this.cameraSectionPos;
    }

    public void setDirty(int sectionX, int sectionY, int sectionZ, boolean playerChanged) {
        SectionRenderDispatcher.RenderSection section = this.getRenderSection(sectionX, sectionY, sectionZ);
        if (section != null) {
            section.setDirty(playerChanged);
        }
    }

    protected @Nullable SectionRenderDispatcher.RenderSection getRenderSectionAt(BlockPos pos) {
        return this.getRenderSection(SectionPos.asLong(pos));
    }

    protected @Nullable SectionRenderDispatcher.RenderSection getRenderSection(long sectionNode) {
        int sectionX = SectionPos.x(sectionNode);
        int sectionY = SectionPos.y(sectionNode);
        int sectionZ = SectionPos.z(sectionNode);
        return this.getRenderSection(sectionX, sectionY, sectionZ);
    }

    private @Nullable SectionRenderDispatcher.RenderSection getRenderSection(int sectionX, int sectionY, int sectionZ) {
        if (!this.containsSection(sectionX, sectionY, sectionZ)) {
            return null;
        }
        int y = sectionY - this.level.getMinSectionY();
        int x = Math.floorMod(sectionX, this.sectionGridSizeX);
        int z = Math.floorMod(sectionZ, this.sectionGridSizeZ);
        return this.sections[this.getSectionIndex(x, y, z)];
    }

    private boolean containsSection(int sectionX, int sectionY, int sectionZ) {
        if (sectionY < this.level.getMinSectionY() || sectionY > this.level.getMaxSectionY()) {
            return false;
        }
        if (sectionX < this.cameraSectionPos.x() - this.viewDistance || sectionX > this.cameraSectionPos.x() + this.viewDistance) {
            return false;
        }
        return sectionZ >= this.cameraSectionPos.z() - this.viewDistance && sectionZ <= this.cameraSectionPos.z() + this.viewDistance;
    }
}