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// Inline lexer
'use strict';
var StateInline = require('./lexer_inline/state_inline');
var links = require('./lexer_inline/links');
var skipSpaces = require('./helpers').skipSpaces;
////////////////////////////////////////////////////////////////////////////////
// Lexer rules
var rules = [];
// Pure text
rules.push(require('./lexer_inline/text'));
rules.push(require('./lexer_inline/newline'));
rules.push(require('./lexer_inline/escape'));
rules.push(require('./lexer_inline/backticks'));
//
//
rules.push(require('./lexer_inline/emphasis'));
rules.push(require('./lexer_inline/links'));
rules.push(require('./lexer_inline/autolink'));
rules.push(require('./lexer_inline/htmltag'));
rules.push(require('./lexer_inline/entity'));
rules.push(require('./lexer_inline/escape_html_char'));
////////////////////////////////////////////////////////////////////////////////
// Lexer class
function functionName(fn) {
var ret = fn.toString();
ret = ret.substr('function '.length);
ret = ret.substr(0, ret.indexOf('('));
return ret;
}
function findByName(self, name) {
for (var i = 0; i < self.rules.length; i++) {
if (functionName(self.rules[i]) === name) {
return i;
}
}
return -1;
}
// Block Lexer class
//
function LexerInline() {
this.rules = [];
// Rule to skip pure text
// - '{$%@}' reserved for extentions
// - '<>"' added for internal html escaping
this.textMatch = /^[^\n\\`*_\[\]!&{}$%@<>"]+/;
for (var i = 0; i < rules.length; i++) {
this.after(null, rules[i]);
}
}
// Replace/delete lexer function
//
LexerInline.prototype.at = function (name, fn) {
var index = findByName(name);
if (index === -1) {
throw new Error('Lexer rule not found: ' + name);
}
if (fn) {
this.rules[index] = fn;
} else {
this.rules = this.rules.slice(0, index).concat(this.rules.slice(index + 1));
}
};
// Add function to lexer chain before one with given name.
// Or add to start, if name not defined
//
LexerInline.prototype.before = function (name, fn) {
if (!name) {
this.rules.unshift(fn);
return;
}
var index = findByName(name);
if (index === -1) {
throw new Error('Lexer rule not found: ' + name);
}
this.rules.splice(index, 0, fn);
};
// Add function to lexer chain after one with given name.
// Or add to end, if name not defined
//
LexerInline.prototype.after = function (name, fn) {
if (!name) {
this.rules.push(fn);
return;
}
var index = findByName(name);
if (index === -1) {
throw new Error('Lexer rule not found: ' + name);
}
this.rules.splice(index + 1, 0, fn);
};
// Generate tokens for input range
//
LexerInline.prototype.tokenize = function (state) {
var ok, i,
rules = this.rules,
len = this.rules.length,
end = state.posMax;
while (state.pos < end) {
// Try all possible rules.
// On success, rule should:
//
// - update `state.pos`
// - update `state.tokens`
// - return true
for (i = 0; i < len; i++) {
ok = rules[i](state);
if (ok) { break; }
}
if (ok) {
if (state.pos >= end) { break; }
continue;
}
state.pending += state.src[state.pos++];
}
if (state.pending) {
state.pushPending();
}
return state.tokens;
};
// Parse input string.
//
LexerInline.prototype.parse = function (str, options, env) {
var state = new StateInline(str, this, options, env);
this.tokenize(state);
return state.tokens;
};
// Parse link reference definition.
//
LexerInline.prototype.parse_reference = function (str, options) {
var state, labelEnd, pos, max, code, start, href, title;
if (str.charCodeAt(0) !== 0x5B/* [ */) { return null; }
state = new StateInline(str, this, options);
labelEnd = links.parseLinkLabel(state, 0);
if (labelEnd < 0 || str.charCodeAt(labelEnd + 1) !== 0x3A/* : */) { return null; }
max = state.posMax;
// [label]: destination 'title'
// ^^^ skip optional whitespace here
for (pos = labelEnd + 2; pos < max; pos++) {
code = state.src.charCodeAt(pos);
if (code !== 0x20 && code !== 0x0A) { break; }
}
// [label]: destination 'title'
// ^^^^^^^^^^^ parse this
href = links.parseLinkDestination(state, pos);
if (href === null) { return null; }
pos = state.pos;
// [label]: destination 'title'
// ^^^ skipping those spaces
start = pos;
for (pos = pos + 1; pos < max; pos++) {
code = state.src.charCodeAt(pos);
if (code !== 0x20 && code !== 0x0A) { break; }
}
// [label]: destination 'title'
// ^^^^^^^ parse this
if (pos < max && start !== pos && (title = links.parseLinkTitle(state, pos)) !== null) {
pos = state.pos;
} else {
title = '';
pos = start;
}
// ensure that the end of the line is empty
pos = skipSpaces(state, pos);
if (pos < max && state.src.charCodeAt(pos) !== 0x0A) { return null; }
return {
label: links.normalizeReference(str.slice(1, labelEnd)),
title: title,
href: href,
remaining: str.slice(pos)
};
};
module.exports = LexerInline;