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'use strict';
function isNodeType(node, type) {
return node && node.type === type;
}
function serializeMultiplier(multiplier) {
if (multiplier.min === 0 && multiplier.max === 0) {
return '*';
}
if (multiplier.min === 0 && multiplier.max === 1) {
return '?';
}
if (multiplier.min === 1 && multiplier.max === 0) {
return multiplier.comma ? '#' : '+';
}
if (multiplier.min === 1 && multiplier.max === 1) {
return '';
}
return (
(multiplier.comma ? '#' : '') +
'{' + multiplier.min + (multiplier.min !== multiplier.max ? ',' + (multiplier.max !== 0 ? multiplier.max : '') : '') + '}'
);
}
function generateSequence(node, forceBraces, decorate) {
var result = '';
if (node.explicit || forceBraces) {
result += '[' + (!isNodeType(node.terms[0], 'Comma') ? ' ' : '');
}
result += node.terms.map(function(term) {
return generate(term, forceBraces, decorate);
}).join(node.combinator === ' ' ? ' ' : ' ' + node.combinator + ' ');
if (node.explicit || forceBraces) {
result += ' ]';
}
return result;
}
function generateParentheses(group, forceBraces, decorate) {
if (!group.terms.length) {
return '()';
}
return '( ' + generateSequence(group, forceBraces, decorate) + ' )';
}
function generate(node, forceBraces, decorate) {
var result;
switch (node.type) {
case 'Group':
result =
generateSequence(node, forceBraces, decorate) +
(node.disallowEmpty ? '!' : '') +
serializeMultiplier(node.multiplier);
break;
case 'Keyword':
result = node.name;
break;
case 'Function':
result = node.name + generateParentheses(node.children, forceBraces, decorate);
break;
case 'Parentheses': // replace for seq('(' seq(...node.children) ')')
result = generateParentheses(node.children, forceBraces, decorate);
break;
case 'Type':
result = '<' + node.name + '>';
break;
case 'Property':
result = '<\'' + node.name + '\'>';
break;
case 'Combinator': // remove?
case 'Slash': // replace for String? '/'
case 'Percent': // replace for String? '%'
case 'String':
case 'Comma':
result = node.value;
break;
default:
throw new Error('Unknown node type `' + node.type + '`');
}
if (typeof decorate === 'function') {
result = decorate(result, node);
}
return result;
}
module.exports = generate;