package com.blt.talk.common.code;

import java.nio.charset.Charset;
import java.nio.charset.StandardCharsets;

import io.netty.buffer.ByteBuf;
import io.netty.buffer.ByteBufUtil;

/**
 * 数据缓冲区对象(ByteBuf)
 * 
 * @author 袁贵
 * @version 1.0
 * @since 1.0
 */
public final class DataBuffer {

    /** the data buffer's content */
    public ByteBuf buffer;

    public DataBuffer() {
        buffer = ByteBufUtil.threadLocalDirectBuffer(); // ByteBufs.dynamicBuffer();
    }

    public DataBuffer(ByteBuf binaryBuffer) {
        buffer = binaryBuffer;
    }

    public DataBuffer(int length) {
        buffer = ByteBufUtil.threadLocalDirectBuffer();// ByteBufs.buffer(length);
        buffer.capacity(length);
    }

    public byte[] array() {
        if (buffer.hasArray()) {
            return buffer.array();
        } else {
            buffer.resetReaderIndex();
            byte[] content = new byte[buffer.writerIndex()];
            buffer.readBytes(content);
            return content;
        }
    }

    public void setOrignalBuffer(ByteBuf buffer) {
        this.buffer = buffer;
    }

    public ByteBuf getOrignalBuffer() {
        return buffer;
    }

    public void writeByte(int value) {
        buffer.writeByte(value);
    }

    public byte readByte() {
        return buffer.readByte();
    }

    public byte[] readBytes(int length) {
        byte[] bytes = new byte[length];
        buffer.readBytes(bytes);
        return bytes;
    }

    public int readInt() {
        if (buffer.isReadable()) {
            return buffer.readInt();
        } else {
            return 0;
        }
    }

    public void writeShort(short value) {
        buffer.writeShort(value);
    }

    public short readShort() {
        if (buffer.isReadable()) {
            return buffer.readShort();
        } else {
            return 0;
        }
    }

    public void writeInt(int value) {
        buffer.writeInt(value);
    }

    public char readChar() {
        return buffer.readChar();
    }

    public void writeChar(char c) {
        buffer.writeChar(c);
    }

    public long readLong() {
        return buffer.readLong();
    }

    public void writeLong(long value) {
        buffer.writeLong(value);
    }

    public double readDouble() {
        return buffer.readDouble();
    }

    public void writeDouble(double value) {
        buffer.writeDouble(value);
    }

    /**
     * 读取一个字符串
     * 
     * @return 格式：前导length表示字符串的byte数 length(4字节)string(length字节)
     */
    public String readString() {
        int length = readInt();
        // logger.d("debug#length:%d", length);

        byte[] bytes = readBytes(length);

        return new String(bytes, StandardCharsets.UTF_8);
    }

    public String readString(int length) {
        byte[] bytes = readBytes(length);

        return new String(bytes, StandardCharsets.UTF_8);
    }

    public void writeBytes(byte[] bytes) {
        buffer.writeBytes(bytes);
    }

    public void writeSourceBytes(byte[] bytes) {
        writeInt(bytes.length);
        buffer.writeBytes(bytes);
    }

    /**
     * 读取int数组
     * 
     * @return 格式：前导count表示数组中有多少个元素 count(4字节)int1(4字节)...intCount(4字节)
     */
    public int[] readIntArray() {
        int count = readInt();
        int[] intArray = new int[count];
        for (int i = 0; i < count; i++) {
            intArray[i] = readInt();
        }
        return intArray;
    }

    /**
     * 写入int数组
     * 
     * @param intArray 格式见readIntArray()
     */
    public void writeIntArray(int[] intArray) {
        int count = intArray.length;
        writeInt(count);
        for (int i = 0; i < count; i++) {
            writeInt(intArray[i]);
        }
    }

    /**
     * 获取有效(可读取)的byte数
     * 
     * @return
     */
    public int readableBytes() {
        return buffer.readableBytes();
    }

    public DataBuffer readDataBuffer() {
        if (null == buffer || buffer.readableBytes() == 0) {
            return new DataBuffer(0);
        }
        int length = readInt();
        DataBuffer dataBuffer = new DataBuffer(0);
        dataBuffer.setOrignalBuffer(buffer.readBytes(length));
        return dataBuffer;
    }

    public void writeDataBuffer(DataBuffer inputBuffer) {
        if (null == inputBuffer || inputBuffer.readableBytes() == 0) {
            return;
        }
        buffer.writeBytes(inputBuffer.buffer);
    }

    public void resetReaderIndex() {
        buffer.resetReaderIndex();
    }

    public void resetWriterIndex() {
        buffer.resetWriterIndex();
    }
}