/*
 * Decompiled with CFR 0.152.
 */
package net.minecraft.util;

import java.io.ByteArrayInputStream;
import java.io.DataInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.nio.ByteBuffer;
import java.nio.ByteOrder;
import java.util.HexFormat;

public record PngInfo(int width, int height) {
    private static final HexFormat FORMAT = HexFormat.of().withUpperCase().withPrefix("0x");
    private static final long PNG_HEADER = -8552249625308161526L;
    private static final int IHDR_TYPE = 1229472850;
    private static final int IHDR_SIZE = 13;

    public static PngInfo fromStream(InputStream inputStream) throws IOException {
        DataInputStream stream = new DataInputStream(inputStream);
        long magic = stream.readLong();
        if (magic != -8552249625308161526L) {
            throw new IOException("Bad PNG Signature: " + FORMAT.toHexDigits(magic));
        }
        int headerSize = stream.readInt();
        if (headerSize != 13) {
            throw new IOException("Bad length for IHDR chunk: " + headerSize);
        }
        int headerType = stream.readInt();
        if (headerType != 1229472850) {
            throw new IOException("Bad type for IHDR chunk: " + FORMAT.toHexDigits(headerType));
        }
        int width = stream.readInt();
        int height = stream.readInt();
        return new PngInfo(width, height);
    }

    public static PngInfo fromBytes(byte[] bytes) throws IOException {
        return PngInfo.fromStream(new ByteArrayInputStream(bytes));
    }

    public static void validateHeader(ByteBuffer buffer) throws IOException {
        ByteOrder order = buffer.order();
        buffer.order(ByteOrder.BIG_ENDIAN);
        if (buffer.limit() < 16) {
            throw new IOException("PNG header missing");
        }
        if (buffer.getLong(0) != -8552249625308161526L) {
            throw new IOException("Bad PNG Signature");
        }
        if (buffer.getInt(8) != 13) {
            throw new IOException("Bad length for IHDR chunk!");
        }
        if (buffer.getInt(12) != 1229472850) {
            throw new IOException("Bad type for IHDR chunk!");
        }
        buffer.order(order);
    }
}