rochars / byte-data

 * to-bytes: bytes to numbers and strings.

 * Copyright (c) 2017 Rafael da Silva Rocha.

 * https://github.com/rochars/byte-data

 */

const helpers = require("../src/helpers.js");

/**

 * Turn numbers and strings to bytes.

 * @param {!Array<number>|number|string} values The data.

 * @param {Object} type One of the available types.

 * @return {!Array<number>|!Array<string>|Uint8Array} the data as a byte buffer.

 */

function toBytes(values, type) {

    let bytes = writeBytes(values, type);

    helpers.makeBigEndian(bytes, type);

    helpers.outputToBase(bytes, type.bits, type.base);

    helpers.fixFloat16Endianness(bytes, type);

    return bytes;

}

/**

 * Write values as bytes.

 * @param {!Array<number>|number|string} values The data.

 * @param {Object} type One of the available types.

 * @return {!Array<number>} the bytes.

 */

function writeBytes(values, type) {

    let i = 0;

    let j = 0;

    let len = values.length;

    let bytes = [];

    while (i < len) {

        j = type.writer(bytes, checkOverflow(values[i], type), j);

        i++;

    }

    return bytes;

}

/**

 * Limit the value according to the bit depth in case of

 * overflow or underflow.

 * @param {!Array<number>|number|string} value The data.

 * @param {Object} type The maximum value.

 */

function checkOverflow(value, type) {

    if (!type.float) {

        if (value > type.max) {

            value = type.max;

        } else if(value < type.min) {

            value = type.min;

        }

    }

    return value;

}