44 lines
1.2 KiB
JavaScript
44 lines
1.2 KiB
JavaScript
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const Mode = require('./mode')
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function NumericData (data) {
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this.mode = Mode.NUMERIC
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this.data = data.toString()
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}
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NumericData.getBitsLength = function getBitsLength (length) {
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return 10 * Math.floor(length / 3) + ((length % 3) ? ((length % 3) * 3 + 1) : 0)
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}
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NumericData.prototype.getLength = function getLength () {
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return this.data.length
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}
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NumericData.prototype.getBitsLength = function getBitsLength () {
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return NumericData.getBitsLength(this.data.length)
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}
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NumericData.prototype.write = function write (bitBuffer) {
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let i, group, value
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// The input data string is divided into groups of three digits,
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// and each group is converted to its 10-bit binary equivalent.
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for (i = 0; i + 3 <= this.data.length; i += 3) {
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group = this.data.substr(i, 3)
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value = parseInt(group, 10)
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bitBuffer.put(value, 10)
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}
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// If the number of input digits is not an exact multiple of three,
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// the final one or two digits are converted to 4 or 7 bits respectively.
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const remainingNum = this.data.length - i
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if (remainingNum > 0) {
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group = this.data.substr(i)
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value = parseInt(group, 10)
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bitBuffer.put(value, remainingNum * 3 + 1)
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}
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}
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module.exports = NumericData
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