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// Parser state class
'use strict';
var Token = require('../token');
var isSpace = require('../common/utils').isSpace;
function StateBlock(src, md, env, tokens) {
var ch, s, start, pos, len, indent, offset, indent_found;
this.src = src;
// link to parser instance
this.md = md;
this.env = env;
//
// Internal state vartiables
//
this.tokens = tokens;
this.bMarks = []; // line begin offsets for fast jumps
this.eMarks = []; // line end offsets for fast jumps
this.tShift = []; // offsets of the first non-space characters (tabs not expanded)
this.sCount = []; // indents for each line (tabs expanded)
// An amount of virtual spaces (tabs expanded) between beginning
// of each line (bMarks) and real beginning of that line.
//
// It exists only as a hack because blockquotes override bMarks
// losing information in the process.
//
// It's used only when expanding tabs, you can think about it as
// an initial tab length, e.g. bsCount=21 applied to string `\t123`
// means first tab should be expanded to 4-21%4 === 3 spaces.
//
this.bsCount = [];
// block parser variables
this.blkIndent = 0; // required block content indent
// (for example, if we are in list)
this.line = 0; // line index in src
this.lineMax = 0; // lines count
this.tight = false; // loose/tight mode for lists
this.ddIndent = -1; // indent of the current dd block (-1 if there isn't any)
// can be 'blockquote', 'list', 'root', 'paragraph' or 'reference'
// used in lists to determine if they interrupt a paragraph
this.parentType = 'root';
this.level = 0;
// renderer
this.result = '';
// Create caches
// Generate markers.
s = this.src;
indent_found = false;
for (start = pos = indent = offset = 0, len = s.length; pos < len; pos++) {
ch = s.charCodeAt(pos);
if (!indent_found) {
if (isSpace(ch)) {
indent++;
if (ch === 0x09) {
offset += 4 - offset % 4;
} else {
offset++;
}
continue;
} else {
indent_found = true;
}
}
if (ch === 0x0A || pos === len - 1) {
if (ch !== 0x0A) { pos++; }
this.bMarks.push(start);
this.eMarks.push(pos);
this.tShift.push(indent);
this.sCount.push(offset);
this.bsCount.push(0);
indent_found = false;
indent = 0;
offset = 0;
start = pos + 1;
}
}
// Push fake entry to simplify cache bounds checks
this.bMarks.push(s.length);
this.eMarks.push(s.length);
this.tShift.push(0);
this.sCount.push(0);
this.bsCount.push(0);
this.lineMax = this.bMarks.length - 1; // don't count last fake line
}
// Push new token to "stream".
//
StateBlock.prototype.push = function (type, tag, nesting) {
var token = new Token(type, tag, nesting);
token.block = true;
if (nesting < 0) { this.level--; }
token.level = this.level;
if (nesting > 0) { this.level++; }
this.tokens.push(token);
return token;
};
StateBlock.prototype.isEmpty = function isEmpty(line) {
return this.bMarks[line] + this.tShift[line] >= this.eMarks[line];
};
StateBlock.prototype.skipEmptyLines = function skipEmptyLines(from) {
for (var max = this.lineMax; from < max; from++) {
if (this.bMarks[from] + this.tShift[from] < this.eMarks[from]) {
break;
}
}
return from;
};
// Skip spaces from given position.
StateBlock.prototype.skipSpaces = function skipSpaces(pos) {
var ch;
for (var max = this.src.length; pos < max; pos++) {
ch = this.src.charCodeAt(pos);
if (!isSpace(ch)) { break; }
}
return pos;
};
// Skip spaces from given position in reverse.
StateBlock.prototype.skipSpacesBack = function skipSpacesBack(pos, min) {
if (pos <= min) { return pos; }
while (pos > min) {
if (!isSpace(this.src.charCodeAt(--pos))) { return pos + 1; }
}
return pos;
};
// Skip char codes from given position
StateBlock.prototype.skipChars = function skipChars(pos, code) {
for (var max = this.src.length; pos < max; pos++) {
if (this.src.charCodeAt(pos) !== code) { break; }
}
return pos;
};
// Skip char codes reverse from given position - 1
StateBlock.prototype.skipCharsBack = function skipCharsBack(pos, code, min) {
if (pos <= min) { return pos; }
while (pos > min) {
if (code !== this.src.charCodeAt(--pos)) { return pos + 1; }
}
return pos;
};
// cut lines range from source.
StateBlock.prototype.getLines = function getLines(begin, end, indent, keepLastLF) {
var i, lineIndent, ch, first, last, queue, lineStart,
line = begin;
if (begin >= end) {
return '';
}
queue = new Array(end - begin);
for (i = 0; line < end; line++, i++) {
lineIndent = 0;
lineStart = first = this.bMarks[line];
if (line + 1 < end || keepLastLF) {
// No need for bounds check because we have fake entry on tail.
last = this.eMarks[line] + 1;
} else {
last = this.eMarks[line];
}
while (first < last && lineIndent < indent) {
ch = this.src.charCodeAt(first);
if (isSpace(ch)) {
if (ch === 0x09) {
lineIndent += 4 - (lineIndent + this.bsCount[line]) % 4;
} else {
lineIndent++;
}
} else if (first - lineStart < this.tShift[line]) {
// patched tShift masked characters to look like spaces (blockquotes, list markers)
lineIndent++;
} else {
break;
}
first++;
}
if (lineIndent > indent) {
// partially expanding tabs in code blocks, e.g '\t\tfoobar'
// with indent=2 becomes ' \tfoobar'
queue[i] = new Array(lineIndent - indent + 1).join(' ') + this.src.slice(first, last);
} else {
queue[i] = this.src.slice(first, last);
}
}
return queue.join('');
};
// re-export Token class to use in block rules
StateBlock.prototype.Token = Token;
module.exports = StateBlock;