import { VALID_DIGITS } from '../../constants.js'
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// The RFC 3966 format for extensions.
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const RFC3966_EXTN_PREFIX = ';ext='
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/**
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* Helper method for constructing regular expressions for parsing. Creates
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* an expression that captures up to max_length digits.
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* @return {string} RegEx pattern to capture extension digits.
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*/
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const getExtensionDigitsPattern = (maxLength) => `([${VALID_DIGITS}]{1,${maxLength}})`
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/**
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* Helper initialiser method to create the regular-expression pattern to match
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* extensions.
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* Copy-pasted from Google's `libphonenumber`:
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* https://github.com/google/libphonenumber/blob/55b2646ec9393f4d3d6661b9c82ef9e258e8b829/javascript/i18n/phonenumbers/phonenumberutil.js#L759-L766
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* @return {string} RegEx pattern to capture extensions.
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*/
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export default function createExtensionPattern(purpose) {
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// We cap the maximum length of an extension based on the ambiguity of the way
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// the extension is prefixed. As per ITU, the officially allowed length for
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// extensions is actually 40, but we don't support this since we haven't seen real
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// examples and this introduces many false interpretations as the extension labels
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// are not standardized.
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/** @type {string} */
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var extLimitAfterExplicitLabel = '20';
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/** @type {string} */
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var extLimitAfterLikelyLabel = '15';
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/** @type {string} */
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var extLimitAfterAmbiguousChar = '9';
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/** @type {string} */
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var extLimitWhenNotSure = '6';
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/** @type {string} */
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var possibleSeparatorsBetweenNumberAndExtLabel = "[ \u00A0\\t,]*";
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// Optional full stop (.) or colon, followed by zero or more spaces/tabs/commas.
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/** @type {string} */
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var possibleCharsAfterExtLabel = "[:\\.\uFF0E]?[ \u00A0\\t,-]*";
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/** @type {string} */
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var optionalExtnSuffix = "#?";
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// Here the extension is called out in more explicit way, i.e mentioning it obvious
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// patterns like "ext.".
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/** @type {string} */
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var explicitExtLabels =
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"(?:e?xt(?:ensi(?:o\u0301?|\u00F3))?n?|\uFF45?\uFF58\uFF54\uFF4E?|\u0434\u043E\u0431|anexo)";
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// One-character symbols that can be used to indicate an extension, and less
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// commonly used or more ambiguous extension labels.
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/** @type {string} */
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var ambiguousExtLabels = "(?:[x\uFF58#\uFF03~\uFF5E]|int|\uFF49\uFF4E\uFF54)";
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// When extension is not separated clearly.
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/** @type {string} */
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var ambiguousSeparator = "[- ]+";
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// This is the same as possibleSeparatorsBetweenNumberAndExtLabel, but not matching
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// comma as extension label may have it.
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/** @type {string} */
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var possibleSeparatorsNumberExtLabelNoComma = "[ \u00A0\\t]*";
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// ",," is commonly used for auto dialling the extension when connected. First
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// comma is matched through possibleSeparatorsBetweenNumberAndExtLabel, so we do
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// not repeat it here. Semi-colon works in Iphone and Android also to pop up a
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// button with the extension number following.
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/** @type {string} */
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var autoDiallingAndExtLabelsFound = "(?:,{2}|;)";
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/** @type {string} */
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var rfcExtn = RFC3966_EXTN_PREFIX
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+ getExtensionDigitsPattern(extLimitAfterExplicitLabel);
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/** @type {string} */
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var explicitExtn = possibleSeparatorsBetweenNumberAndExtLabel + explicitExtLabels
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+ possibleCharsAfterExtLabel
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+ getExtensionDigitsPattern(extLimitAfterExplicitLabel)
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+ optionalExtnSuffix;
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/** @type {string} */
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var ambiguousExtn = possibleSeparatorsBetweenNumberAndExtLabel + ambiguousExtLabels
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+ possibleCharsAfterExtLabel
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+ getExtensionDigitsPattern(extLimitAfterAmbiguousChar)
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+ optionalExtnSuffix;
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/** @type {string} */
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var americanStyleExtnWithSuffix = ambiguousSeparator
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+ getExtensionDigitsPattern(extLimitWhenNotSure) + "#";
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/** @type {string} */
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var autoDiallingExtn = possibleSeparatorsNumberExtLabelNoComma
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+ autoDiallingAndExtLabelsFound + possibleCharsAfterExtLabel
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+ getExtensionDigitsPattern(extLimitAfterLikelyLabel)
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+ optionalExtnSuffix;
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/** @type {string} */
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var onlyCommasExtn = possibleSeparatorsNumberExtLabelNoComma
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+ "(?:,)+" + possibleCharsAfterExtLabel
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+ getExtensionDigitsPattern(extLimitAfterAmbiguousChar)
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+ optionalExtnSuffix;
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// The first regular expression covers RFC 3966 format, where the extension is added
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// using ";ext=". The second more generic where extension is mentioned with explicit
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// labels like "ext:". In both the above cases we allow more numbers in extension than
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// any other extension labels. The third one captures when single character extension
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// labels or less commonly used labels are used. In such cases we capture fewer
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// extension digits in order to reduce the chance of falsely interpreting two
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// numbers beside each other as a number + extension. The fourth one covers the
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// special case of American numbers where the extension is written with a hash
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// at the end, such as "- 503#". The fifth one is exclusively for extension
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// autodialling formats which are used when dialling and in this case we accept longer
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// extensions. The last one is more liberal on the number of commas that acts as
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// extension labels, so we have a strict cap on the number of digits in such extensions.
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return rfcExtn + "|"
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+ explicitExtn + "|"
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+ ambiguousExtn + "|"
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+ americanStyleExtnWithSuffix + "|"
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+ autoDiallingExtn + "|"
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+ onlyCommasExtn;
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}
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