summaryrefslogtreecommitdiff
path: root/Build/source/texk/dvisvgm/dvisvgm-1.0.3/src/PageRanges.cpp
blob: 85a124683c7dfc06b09b941ce865ad6ed7b1e68e (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
/*************************************************************************
** PageRanges.cpp                                                       **
**                                                                      **
** This file is part of dvisvgm -- the DVI to SVG converter             **
** Copyright (C) 2005-2010 Martin Gieseking <martin.gieseking@uos.de>   **
**                                                                      **
** This program is free software; you can redistribute it and/or        **
** modify it under the terms of the GNU General Public License as       **
** published by the Free Software Foundation; either version 3 of       **
** the License, or (at your option) any later version.                  **
**                                                                      **
** This program is distributed in the hope that it will be useful, but  **
** WITHOUT ANY WARRANTY; without even the implied warranty of           **
** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the         **
** GNU General Public License for more details.                         **
**                                                                      **
** You should have received a copy of the GNU General Public License    **
** along with this program; if not, see <http://www.gnu.org/licenses/>. **
*************************************************************************/

#include <sstream>
#include "InputBuffer.h"
#include "InputReader.h"
#include "PageRanges.h"

#include "macros.h"

using namespace std;


/** Analyzes a string describing a range sequence.
 *  Syntax: ([0-9]+(-[0-9]*)?)|(-[0-9]+)(,([0-9]+(-[0-9]*)?)|(-[0-9]+))*
 *  @param[in] str string to parse
 *  @param[in] max_page greatest allowed value
 *  @param[out] ranges the extracted range sequence
 *  @return true on success; false denotes a syntax error */
bool PageRanges::parse (string str, int max_page) {
	StringInputBuffer ib(str);
	BufferInputReader ir(ib);
	while (ir) {
		int first=1;
		int last=max_page;
		ir.skipSpace();
		if (!isdigit(ir.peek()) && ir.peek() != '-')
			return false;

		if (isdigit(ir.peek()))
			first = ir.getInt();
		ir.skipSpace();
		if (ir.peek() == '-') {
			while (ir.peek() == '-')
				ir.get();
			ir.skipSpace();
			if (isdigit(ir.peek()))
				last = ir.getInt();
		}
		else
			last = first;
		ir.skipSpace();
		if (ir.peek() == ',') {
			ir.get();
			if (ir.eof())
				return false;
		}
		else if (!ir.eof())
			return false;
		if (first > last)
			swap(first, last);
		first = max(1, first);
		last  = max(first, last);
		if (max_page > 0) {
			first = min(first, max_page);
			last  = min(last, max_page);
		}
		insert(first, last);
	}
	return true;
}


/** Adds a page range to the range collection.
 *  @param[in] first first page of new range
 *  @param[in] last last page of new range */
void PageRanges::insert (int first, int last) {
	if (first > last)
		swap(first, last);
	Container::iterator it = _ranges.begin();
	while (it != _ranges.end() && first > it->first+1 && first > it->second+1)
		++it;
	if (it == _ranges.end() || last < it->first-1 || first > it->second+1)
		it = _ranges.insert(it, Range(first, last));
	else if ((first < it->first && last >= it->first-1) || (first <= it->second+1 && last > it->second)) {
		it->first = min(it->first, first);
		it->second = max(it->second, last);
	}
	// merge adjacent ranges
	if (it != _ranges.end()) {
		Container::iterator l = it;
		Container::iterator r = it;
		if (l == _ranges.begin())
			l = _ranges.end();
		else
			--l;
		++r;
		bool l_modified = false;
		bool r_modified = false;
		if (l != _ranges.end() && l->second >= it->first-1) {
			l->first = min(l->first, it->first);
			l->second = max(l->second, it->second);
			l_modified = true;
		}
		if (r != _ranges.end() && r->first <= it->second+1) {
			r->first = min(r->first, it->first);
			r->second = max(r->second, it->second);
			r_modified = true;
		}
		if (l_modified || r_modified) {
			_ranges.erase(it);
			if (l_modified && r_modified && l->second >= r->first-1) {
				l->first = min(l->first, r->first);
				l->second = max(l->second, r->second);
				_ranges.erase(r);
			}
		}
	}
}


/** Returns the number of pages. */
size_t PageRanges::pages () const {
	size_t sum=0;
	for (ConstIterator it=_ranges.begin(); it != _ranges.end(); ++it)
		sum += it->second - it->first + 1;
	return sum;
}