occaecatidicta/packages/omelox-rpc/lib/util/buffer/outputBuffer.ts

import { getLogger } from 'omelox-logger';
let logger = getLogger('omelox-rpc', 'OutputBuffer');
import * as Utils from '../utils';
let BUFFER_SIZE_DEFAULT = 32;

export class OutputBuffer {
    count = 0;
    size: number;
    offset: number = 0;
    buf: Buffer;
    constructor(size?: number) {
        this.size = size || BUFFER_SIZE_DEFAULT;
        this.buf = Buffer.alloc(this.size);
    }

    getData() {
        return this.buf;
    }

    getLength() {
        return this.count;
    }

    write(data: string, offset: number, len: number) {
        this.ensureCapacity(len);
        this.buf.write(data, offset, len);
        this.count += len;
    }

    writeBoolean(v: boolean) {
        this.writeByte(v ? 1 : 0);
    }

    writeByte(v: number) {
        this.ensureCapacity(1);
        this.buf.writeUInt8(v, this.count++);
    }

    writeBytes(bytes: Array<number>) {
        let len = bytes.length;
        this.ensureCapacity(len + 4);
        this.writeInt(len);
        for (let i = 0; i < len; i++) {
            this.buf.writeUInt8(bytes[i], this.count++);
        }
    }

    writeChar(v: number) {
        this.writeByte(v);
    }

    writeChars(bytes: Array<number>) {
        this.writeBytes(bytes);
    }

    writeDouble(v: number) {
        this.ensureCapacity(8);
        this.buf.writeDoubleLE(v, this.count);
        this.count += 8;
    }

    writeFloat(v: number) {
        this.ensureCapacity(4);
        this.buf.writeFloatLE(v, this.count);
        this.count += 4;
    }

    writeInt(v: number) {
        this.ensureCapacity(4);
        this.buf.writeInt32LE(v, this.count);
        this.count += 4;
    }

    writeShort(v: number) {
        this.ensureCapacity(2);
        this.buf.writeInt16LE(v, this.count);
        this.count += 2;
    }

    writeUInt(v: number) {
        this.ensureCapacity(4);
        this.buf.writeUInt32LE(v, this.count);
        this.count += 4;
    }

    writeUShort(v: number) {
        this.ensureCapacity(2);
        this.buf.writeUInt16LE(v, this.count);
        this.count += 2;
    }

    writeString(str: string) {
        let len = Buffer.byteLength(str);
        this.ensureCapacity(len + 4);
        this.writeInt(len);
        this.buf.write(str, this.count, len);
        this.count += len;
    }

    writeObject(object: any) {
        let type = Utils.getType(object);
        // console.log('writeObject type %s', type);
        // console.log(object)
        if (!type) {
            logger.error('invalid writeObject ' + object);
            return;
        }

        this.writeShort(type);

        let typeMap = Utils.typeMap;

        if (typeMap['null'] === type) {
            return;
        }

        if (typeMap['buffer'] === type) {
            this.writeBytes(object);
            return;
        }

        if (typeMap['array'] === type) {
            let len = object.length;
            this.writeInt(len);
            for (let i = 0; i < len; i++) {
                this.writeObject(object[i]);
            }
            return;
        }

        if (typeMap['string'] === type) {
            this.writeString(object);
            return;
        }

        if (typeMap['object'] === type) {
            this.writeString(JSON.stringify(object));
            // logger.error('invalid writeObject object must be bearcat beans and should implement writeFields and readFields interfaces');
            return;
        }

        if (typeMap['bean'] === type) {
            this.writeString(object['$id']);
            object.writeFields(this);
            return;
        }

        if (typeMap['boolean'] === type) {
            this.writeBoolean(object);
            return;
        }

        if (typeMap['float'] === type) {
            this.writeFloat(object);
            return;
        }

        if (typeMap['number'] === type) {
            this.writeInt(object);
            return;
        }
    }

    ensureCapacity(len: number) {
        let minCapacity = this.count + len;
        if (minCapacity > this.buf.length) {
            this.grow(minCapacity); // double grow
        }
    }

    grow(minCapacity: number) {
        let oldCapacity = this.buf.length;
        let newCapacity = oldCapacity << 1;
        if (newCapacity - minCapacity < 0) {
            newCapacity = minCapacity;
        }

        if (newCapacity < 0 && minCapacity < 0) {
            throw new Error('OutOfMemoryError');
            // newCapacity = 0x7fffffff; // Integer.MAX_VALUE
        }

        // console.log('grow minCapacity %d newCapacity %d', minCapacity, newCapacity);
        let newBuf = Buffer.alloc(newCapacity);
        this.buf.copy(newBuf);
        this.buf = newBuf;
    }
    getBuffer() {
        return this.buf.slice(0, this.offset);
    }

}