1<?php
2/**
3*  Class for parsing Excel formulas
4*
5*  License Information:
6*
7*    Spreadsheet_Excel_Writer:  A library for generating Excel Spreadsheets
8*    Copyright (c) 2002-2003 Xavier Noguer xnoguer@rezebra.com
9*
10*    This library is free software; you can redistribute it and/or
11*    modify it under the terms of the GNU Lesser General Public
12*    License as published by the Free Software Foundation; either
13*    version 2.1 of the License, or (at your option) any later version.
14*
15*    This library is distributed in the hope that it will be useful,
16*    but WITHOUT ANY WARRANTY; without even the implied warranty of
17*    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
18*    Lesser General Public License for more details.
19*
20*    You should have received a copy of the GNU Lesser General Public
21*    License along with this library; if not, write to the Free Software
22*    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
23*/
24
25/**
26* @const SPREADSHEET_EXCEL_WRITER_ADD token identifier for character "+"
27*/
28define('SPREADSHEET_EXCEL_WRITER_ADD',"+");
29
30/**
31* @const SPREADSHEET_EXCEL_WRITER_SUB token identifier for character "-"
32*/
33define('SPREADSHEET_EXCEL_WRITER_SUB',"-");
34
35/**
36* @const SPREADSHEET_EXCEL_WRITER_MUL token identifier for character "*"
37*/
38define('SPREADSHEET_EXCEL_WRITER_MUL',"*");
39
40/**
41* @const SPREADSHEET_EXCEL_WRITER_DIV token identifier for character "/"
42*/
43define('SPREADSHEET_EXCEL_WRITER_DIV',"/");
44
45/**
46* @const SPREADSHEET_EXCEL_WRITER_OPEN token identifier for character "("
47*/
48define('SPREADSHEET_EXCEL_WRITER_OPEN',"(");
49
50/**
51* @const SPREADSHEET_EXCEL_WRITER_CLOSE token identifier for character ")"
52*/
53define('SPREADSHEET_EXCEL_WRITER_CLOSE',")");
54
55/**
56* @const SPREADSHEET_EXCEL_WRITER_COMA token identifier for character ","
57*/
58define('SPREADSHEET_EXCEL_WRITER_COMA',",");
59
60/**
61* @const SPREADSHEET_EXCEL_WRITER_SEMICOLON token identifier for character ";"
62*/
63define('SPREADSHEET_EXCEL_WRITER_SEMICOLON',";");
64
65/**
66* @const SPREADSHEET_EXCEL_WRITER_GT token identifier for character ">"
67*/
68define('SPREADSHEET_EXCEL_WRITER_GT',">");
69
70/**
71* @const SPREADSHEET_EXCEL_WRITER_LT token identifier for character "<"
72*/
73define('SPREADSHEET_EXCEL_WRITER_LT',"<");
74
75/**
76* @const SPREADSHEET_EXCEL_WRITER_LE token identifier for character "<="
77*/
78define('SPREADSHEET_EXCEL_WRITER_LE',"<=");
79
80/**
81* @const SPREADSHEET_EXCEL_WRITER_GE token identifier for character ">="
82*/
83define('SPREADSHEET_EXCEL_WRITER_GE',">=");
84
85/**
86* @const SPREADSHEET_EXCEL_WRITER_EQ token identifier for character "="
87*/
88define('SPREADSHEET_EXCEL_WRITER_EQ',"=");
89
90/**
91* @const SPREADSHEET_EXCEL_WRITER_NE token identifier for character "<>"
92*/
93define('SPREADSHEET_EXCEL_WRITER_NE',"<>");
94
95
96/**
97* Class for parsing Excel formulas
98*
99* @author   Xavier Noguer <xnoguer@rezebra.com>
100* @category FileFormats
101* @package  Spreadsheet_Excel_Writer
102*/
103
104class Spreadsheet_Excel_Writer_Parser extends PEAR
105{
106    /**
107    * The index of the character we are currently looking at
108    * @var integer
109    */
110    var $_current_char;
111
112    /**
113    * The token we are working on.
114    * @var string
115    */
116    var $_current_token;
117
118    /**
119    * The formula to parse
120    * @var string
121    */
122    var $_formula;
123
124    /**
125    * The character ahead of the current char
126    * @var string
127    */
128    var $_lookahead;
129
130    /**
131    * The parse tree to be generated
132    * @var string
133    */
134    var $_parse_tree;
135
136    /**
137    * The byte order. 1 => big endian, 0 => little endian.
138    * @var integer
139    */
140    var $_byte_order;
141
142    /**
143    * Array of external sheets
144    * @var array
145    */
146    var $_ext_sheets;
147
148    /**
149    * Array of sheet references in the form of REF structures
150    * @var array
151    */
152    var $_references;
153
154    /**
155    * The BIFF version for the workbook
156    * @var integer
157    */
158    var $_BIFF_version;
159
160    /**
161    * The class constructor
162    *
163    * @param integer $byte_order The byte order (Little endian or Big endian) of the architecture
164                                 (optional). 1 => big endian, 0 (default) little endian.
165    */
166    function __construct($byte_order, $biff_version)
167    {
168        $this->_current_char  = 0;
169        $this->_BIFF_version  = $biff_version;
170        $this->_current_token = '';       // The token we are working on.
171        $this->_formula       = "";       // The formula to parse.
172        $this->_lookahead     = '';       // The character ahead of the current char.
173        $this->_parse_tree    = '';       // The parse tree to be generated.
174        $this->_initializeHashes();      // Initialize the hashes: ptg's and function's ptg's
175        $this->_byte_order = $byte_order; // Little Endian or Big Endian
176        $this->_ext_sheets = array();
177        $this->_references = array();
178    }
179
180    /**
181    * Initialize the ptg and function hashes.
182    *
183    * @access private
184    */
185    function _initializeHashes()
186    {
187        // The Excel ptg indices
188        $this->ptg = array(
189            'ptgExp'       => 0x01,
190            'ptgTbl'       => 0x02,
191            'ptgAdd'       => 0x03,
192            'ptgSub'       => 0x04,
193            'ptgMul'       => 0x05,
194            'ptgDiv'       => 0x06,
195            'ptgPower'     => 0x07,
196            'ptgConcat'    => 0x08,
197            'ptgLT'        => 0x09,
198            'ptgLE'        => 0x0A,
199            'ptgEQ'        => 0x0B,
200            'ptgGE'        => 0x0C,
201            'ptgGT'        => 0x0D,
202            'ptgNE'        => 0x0E,
203            'ptgIsect'     => 0x0F,
204            'ptgUnion'     => 0x10,
205            'ptgRange'     => 0x11,
206            'ptgUplus'     => 0x12,
207            'ptgUminus'    => 0x13,
208            'ptgPercent'   => 0x14,
209            'ptgParen'     => 0x15,
210            'ptgMissArg'   => 0x16,
211            'ptgStr'       => 0x17,
212            'ptgAttr'      => 0x19,
213            'ptgSheet'     => 0x1A,
214            'ptgEndSheet'  => 0x1B,
215            'ptgErr'       => 0x1C,
216            'ptgBool'      => 0x1D,
217            'ptgInt'       => 0x1E,
218            'ptgNum'       => 0x1F,
219            'ptgArray'     => 0x20,
220            'ptgFunc'      => 0x21,
221            'ptgFuncVar'   => 0x22,
222            'ptgName'      => 0x23,
223            'ptgRef'       => 0x24,
224            'ptgArea'      => 0x25,
225            'ptgMemArea'   => 0x26,
226            'ptgMemErr'    => 0x27,
227            'ptgMemNoMem'  => 0x28,
228            'ptgMemFunc'   => 0x29,
229            'ptgRefErr'    => 0x2A,
230            'ptgAreaErr'   => 0x2B,
231            'ptgRefN'      => 0x2C,
232            'ptgAreaN'     => 0x2D,
233            'ptgMemAreaN'  => 0x2E,
234            'ptgMemNoMemN' => 0x2F,
235            'ptgNameX'     => 0x39,
236            'ptgRef3d'     => 0x3A,
237            'ptgArea3d'    => 0x3B,
238            'ptgRefErr3d'  => 0x3C,
239            'ptgAreaErr3d' => 0x3D,
240            'ptgArrayV'    => 0x40,
241            'ptgFuncV'     => 0x41,
242            'ptgFuncVarV'  => 0x42,
243            'ptgNameV'     => 0x43,
244            'ptgRefV'      => 0x44,
245            'ptgAreaV'     => 0x45,
246            'ptgMemAreaV'  => 0x46,
247            'ptgMemErrV'   => 0x47,
248            'ptgMemNoMemV' => 0x48,
249            'ptgMemFuncV'  => 0x49,
250            'ptgRefErrV'   => 0x4A,
251            'ptgAreaErrV'  => 0x4B,
252            'ptgRefNV'     => 0x4C,
253            'ptgAreaNV'    => 0x4D,
254            'ptgMemAreaNV' => 0x4E,
255            'ptgMemNoMemN' => 0x4F,
256            'ptgFuncCEV'   => 0x58,
257            'ptgNameXV'    => 0x59,
258            'ptgRef3dV'    => 0x5A,
259            'ptgArea3dV'   => 0x5B,
260            'ptgRefErr3dV' => 0x5C,
261            'ptgAreaErr3d' => 0x5D,
262            'ptgArrayA'    => 0x60,
263            'ptgFuncA'     => 0x61,
264            'ptgFuncVarA'  => 0x62,
265            'ptgNameA'     => 0x63,
266            'ptgRefA'      => 0x64,
267            'ptgAreaA'     => 0x65,
268            'ptgMemAreaA'  => 0x66,
269            'ptgMemErrA'   => 0x67,
270            'ptgMemNoMemA' => 0x68,
271            'ptgMemFuncA'  => 0x69,
272            'ptgRefErrA'   => 0x6A,
273            'ptgAreaErrA'  => 0x6B,
274            'ptgRefNA'     => 0x6C,
275            'ptgAreaNA'    => 0x6D,
276            'ptgMemAreaNA' => 0x6E,
277            'ptgMemNoMemN' => 0x6F,
278            'ptgFuncCEA'   => 0x78,
279            'ptgNameXA'    => 0x79,
280            'ptgRef3dA'    => 0x7A,
281            'ptgArea3dA'   => 0x7B,
282            'ptgRefErr3dA' => 0x7C,
283            'ptgAreaErr3d' => 0x7D
284            );
285
286        // Thanks to Michael Meeks and Gnumeric for the initial arg values.
287        //
288        // The following hash was generated by "function_locale.pl" in the distro.
289        // Refer to function_locale.pl for non-English function names.
290        //
291        // The array elements are as follow:
292        // ptg:   The Excel function ptg code.
293        // args:  The number of arguments that the function takes:
294        //           >=0 is a fixed number of arguments.
295        //           -1  is a variable  number of arguments.
296        // class: The reference, value or array class of the function args.
297        // vol:   The function is volatile.
298        //
299        $this->_functions = array(
300              // function                  ptg  args  class  vol
301              'COUNT'           => array(   0,   -1,    0,    0 ),
302              'IF'              => array(   1,   -1,    1,    0 ),
303              'ISNA'            => array(   2,    1,    1,    0 ),
304              'ISERROR'         => array(   3,    1,    1,    0 ),
305              'SUM'             => array(   4,   -1,    0,    0 ),
306              'AVERAGE'         => array(   5,   -1,    0,    0 ),
307              'MIN'             => array(   6,   -1,    0,    0 ),
308              'MAX'             => array(   7,   -1,    0,    0 ),
309              'ROW'             => array(   8,   -1,    0,    0 ),
310              'COLUMN'          => array(   9,   -1,    0,    0 ),
311              'NA'              => array(  10,    0,    0,    0 ),
312              'NPV'             => array(  11,   -1,    1,    0 ),
313              'STDEV'           => array(  12,   -1,    0,    0 ),
314              'DOLLAR'          => array(  13,   -1,    1,    0 ),
315              'FIXED'           => array(  14,   -1,    1,    0 ),
316              'SIN'             => array(  15,    1,    1,    0 ),
317              'COS'             => array(  16,    1,    1,    0 ),
318              'TAN'             => array(  17,    1,    1,    0 ),
319              'ATAN'            => array(  18,    1,    1,    0 ),
320              'PI'              => array(  19,    0,    1,    0 ),
321              'SQRT'            => array(  20,    1,    1,    0 ),
322              'EXP'             => array(  21,    1,    1,    0 ),
323              'LN'              => array(  22,    1,    1,    0 ),
324              'LOG10'           => array(  23,    1,    1,    0 ),
325              'ABS'             => array(  24,    1,    1,    0 ),
326              'INT'             => array(  25,    1,    1,    0 ),
327              'SIGN'            => array(  26,    1,    1,    0 ),
328              'ROUND'           => array(  27,    2,    1,    0 ),
329              'LOOKUP'          => array(  28,   -1,    0,    0 ),
330              'INDEX'           => array(  29,   -1,    0,    1 ),
331              'REPT'            => array(  30,    2,    1,    0 ),
332              'MID'             => array(  31,    3,    1,    0 ),
333              'LEN'             => array(  32,    1,    1,    0 ),
334              'VALUE'           => array(  33,    1,    1,    0 ),
335              'TRUE'            => array(  34,    0,    1,    0 ),
336              'FALSE'           => array(  35,    0,    1,    0 ),
337              'AND'             => array(  36,   -1,    0,    0 ),
338              'OR'              => array(  37,   -1,    0,    0 ),
339              'NOT'             => array(  38,    1,    1,    0 ),
340              'MOD'             => array(  39,    2,    1,    0 ),
341              'DCOUNT'          => array(  40,    3,    0,    0 ),
342              'DSUM'            => array(  41,    3,    0,    0 ),
343              'DAVERAGE'        => array(  42,    3,    0,    0 ),
344              'DMIN'            => array(  43,    3,    0,    0 ),
345              'DMAX'            => array(  44,    3,    0,    0 ),
346              'DSTDEV'          => array(  45,    3,    0,    0 ),
347              'VAR'             => array(  46,   -1,    0,    0 ),
348              'DVAR'            => array(  47,    3,    0,    0 ),
349              'TEXT'            => array(  48,    2,    1,    0 ),
350              'LINEST'          => array(  49,   -1,    0,    0 ),
351              'TREND'           => array(  50,   -1,    0,    0 ),
352              'LOGEST'          => array(  51,   -1,    0,    0 ),
353              'GROWTH'          => array(  52,   -1,    0,    0 ),
354              'PV'              => array(  56,   -1,    1,    0 ),
355              'FV'              => array(  57,   -1,    1,    0 ),
356              'NPER'            => array(  58,   -1,    1,    0 ),
357              'PMT'             => array(  59,   -1,    1,    0 ),
358              'RATE'            => array(  60,   -1,    1,    0 ),
359              'MIRR'            => array(  61,    3,    0,    0 ),
360              'IRR'             => array(  62,   -1,    0,    0 ),
361              'RAND'            => array(  63,    0,    1,    1 ),
362              'MATCH'           => array(  64,   -1,    0,    0 ),
363              'DATE'            => array(  65,    3,    1,    0 ),
364              'TIME'            => array(  66,    3,    1,    0 ),
365              'DAY'             => array(  67,    1,    1,    0 ),
366              'MONTH'           => array(  68,    1,    1,    0 ),
367              'YEAR'            => array(  69,    1,    1,    0 ),
368              'WEEKDAY'         => array(  70,   -1,    1,    0 ),
369              'HOUR'            => array(  71,    1,    1,    0 ),
370              'MINUTE'          => array(  72,    1,    1,    0 ),
371              'SECOND'          => array(  73,    1,    1,    0 ),
372              'NOW'             => array(  74,    0,    1,    1 ),
373              'AREAS'           => array(  75,    1,    0,    1 ),
374              'ROWS'            => array(  76,    1,    0,    1 ),
375              'COLUMNS'         => array(  77,    1,    0,    1 ),
376              'OFFSET'          => array(  78,   -1,    0,    1 ),
377              'SEARCH'          => array(  82,   -1,    1,    0 ),
378              'TRANSPOSE'       => array(  83,    1,    1,    0 ),
379              'TYPE'            => array(  86,    1,    1,    0 ),
380              'ATAN2'           => array(  97,    2,    1,    0 ),
381              'ASIN'            => array(  98,    1,    1,    0 ),
382              'ACOS'            => array(  99,    1,    1,    0 ),
383              'CHOOSE'          => array( 100,   -1,    1,    0 ),
384              'HLOOKUP'         => array( 101,   -1,    0,    0 ),
385              'VLOOKUP'         => array( 102,   -1,    0,    0 ),
386              'ISREF'           => array( 105,    1,    0,    0 ),
387              'LOG'             => array( 109,   -1,    1,    0 ),
388              'CHAR'            => array( 111,    1,    1,    0 ),
389              'LOWER'           => array( 112,    1,    1,    0 ),
390              'UPPER'           => array( 113,    1,    1,    0 ),
391              'PROPER'          => array( 114,    1,    1,    0 ),
392              'LEFT'            => array( 115,   -1,    1,    0 ),
393              'RIGHT'           => array( 116,   -1,    1,    0 ),
394              'EXACT'           => array( 117,    2,    1,    0 ),
395              'TRIM'            => array( 118,    1,    1,    0 ),
396              'REPLACE'         => array( 119,    4,    1,    0 ),
397              'SUBSTITUTE'      => array( 120,   -1,    1,    0 ),
398              'CODE'            => array( 121,    1,    1,    0 ),
399              'FIND'            => array( 124,   -1,    1,    0 ),
400              'CELL'            => array( 125,   -1,    0,    1 ),
401              'ISERR'           => array( 126,    1,    1,    0 ),
402              'ISTEXT'          => array( 127,    1,    1,    0 ),
403              'ISNUMBER'        => array( 128,    1,    1,    0 ),
404              'ISBLANK'         => array( 129,    1,    1,    0 ),
405              'T'               => array( 130,    1,    0,    0 ),
406              'N'               => array( 131,    1,    0,    0 ),
407              'DATEVALUE'       => array( 140,    1,    1,    0 ),
408              'TIMEVALUE'       => array( 141,    1,    1,    0 ),
409              'SLN'             => array( 142,    3,    1,    0 ),
410              'SYD'             => array( 143,    4,    1,    0 ),
411              'DDB'             => array( 144,   -1,    1,    0 ),
412              'INDIRECT'        => array( 148,   -1,    1,    1 ),
413              'CALL'            => array( 150,   -1,    1,    0 ),
414              'CLEAN'           => array( 162,    1,    1,    0 ),
415              'MDETERM'         => array( 163,    1,    2,    0 ),
416              'MINVERSE'        => array( 164,    1,    2,    0 ),
417              'MMULT'           => array( 165,    2,    2,    0 ),
418              'IPMT'            => array( 167,   -1,    1,    0 ),
419              'PPMT'            => array( 168,   -1,    1,    0 ),
420              'COUNTA'          => array( 169,   -1,    0,    0 ),
421              'PRODUCT'         => array( 183,   -1,    0,    0 ),
422              'FACT'            => array( 184,    1,    1,    0 ),
423              'DPRODUCT'        => array( 189,    3,    0,    0 ),
424              'ISNONTEXT'       => array( 190,    1,    1,    0 ),
425              'STDEVP'          => array( 193,   -1,    0,    0 ),
426              'VARP'            => array( 194,   -1,    0,    0 ),
427              'DSTDEVP'         => array( 195,    3,    0,    0 ),
428              'DVARP'           => array( 196,    3,    0,    0 ),
429              'TRUNC'           => array( 197,   -1,    1,    0 ),
430              'ISLOGICAL'       => array( 198,    1,    1,    0 ),
431              'DCOUNTA'         => array( 199,    3,    0,    0 ),
432              'ROUNDUP'         => array( 212,    2,    1,    0 ),
433              'ROUNDDOWN'       => array( 213,    2,    1,    0 ),
434              'RANK'            => array( 216,   -1,    0,    0 ),
435              'ADDRESS'         => array( 219,   -1,    1,    0 ),
436              'DAYS360'         => array( 220,   -1,    1,    0 ),
437              'TODAY'           => array( 221,    0,    1,    1 ),
438              'VDB'             => array( 222,   -1,    1,    0 ),
439              'MEDIAN'          => array( 227,   -1,    0,    0 ),
440              'SUMPRODUCT'      => array( 228,   -1,    2,    0 ),
441              'SINH'            => array( 229,    1,    1,    0 ),
442              'COSH'            => array( 230,    1,    1,    0 ),
443              'TANH'            => array( 231,    1,    1,    0 ),
444              'ASINH'           => array( 232,    1,    1,    0 ),
445              'ACOSH'           => array( 233,    1,    1,    0 ),
446              'ATANH'           => array( 234,    1,    1,    0 ),
447              'DGET'            => array( 235,    3,    0,    0 ),
448              'INFO'            => array( 244,    1,    1,    1 ),
449              'DB'              => array( 247,   -1,    1,    0 ),
450              'FREQUENCY'       => array( 252,    2,    0,    0 ),
451              'ERROR.TYPE'      => array( 261,    1,    1,    0 ),
452              'REGISTER.ID'     => array( 267,   -1,    1,    0 ),
453              'AVEDEV'          => array( 269,   -1,    0,    0 ),
454              'BETADIST'        => array( 270,   -1,    1,    0 ),
455              'GAMMALN'         => array( 271,    1,    1,    0 ),
456              'BETAINV'         => array( 272,   -1,    1,    0 ),
457              'BINOMDIST'       => array( 273,    4,    1,    0 ),
458              'CHIDIST'         => array( 274,    2,    1,    0 ),
459              'CHIINV'          => array( 275,    2,    1,    0 ),
460              'COMBIN'          => array( 276,    2,    1,    0 ),
461              'CONFIDENCE'      => array( 277,    3,    1,    0 ),
462              'CRITBINOM'       => array( 278,    3,    1,    0 ),
463              'EVEN'            => array( 279,    1,    1,    0 ),
464              'EXPONDIST'       => array( 280,    3,    1,    0 ),
465              'FDIST'           => array( 281,    3,    1,    0 ),
466              'FINV'            => array( 282,    3,    1,    0 ),
467              'FISHER'          => array( 283,    1,    1,    0 ),
468              'FISHERINV'       => array( 284,    1,    1,    0 ),
469              'FLOOR'           => array( 285,    2,    1,    0 ),
470              'GAMMADIST'       => array( 286,    4,    1,    0 ),
471              'GAMMAINV'        => array( 287,    3,    1,    0 ),
472              'CEILING'         => array( 288,    2,    1,    0 ),
473              'HYPGEOMDIST'     => array( 289,    4,    1,    0 ),
474              'LOGNORMDIST'     => array( 290,    3,    1,    0 ),
475              'LOGINV'          => array( 291,    3,    1,    0 ),
476              'NEGBINOMDIST'    => array( 292,    3,    1,    0 ),
477              'NORMDIST'        => array( 293,    4,    1,    0 ),
478              'NORMSDIST'       => array( 294,    1,    1,    0 ),
479              'NORMINV'         => array( 295,    3,    1,    0 ),
480              'NORMSINV'        => array( 296,    1,    1,    0 ),
481              'STANDARDIZE'     => array( 297,    3,    1,    0 ),
482              'ODD'             => array( 298,    1,    1,    0 ),
483              'PERMUT'          => array( 299,    2,    1,    0 ),
484              'POISSON'         => array( 300,    3,    1,    0 ),
485              'TDIST'           => array( 301,    3,    1,    0 ),
486              'WEIBULL'         => array( 302,    4,    1,    0 ),
487              'SUMXMY2'         => array( 303,    2,    2,    0 ),
488              'SUMX2MY2'        => array( 304,    2,    2,    0 ),
489              'SUMX2PY2'        => array( 305,    2,    2,    0 ),
490              'CHITEST'         => array( 306,    2,    2,    0 ),
491              'CORREL'          => array( 307,    2,    2,    0 ),
492              'COVAR'           => array( 308,    2,    2,    0 ),
493              'FORECAST'        => array( 309,    3,    2,    0 ),
494              'FTEST'           => array( 310,    2,    2,    0 ),
495              'INTERCEPT'       => array( 311,    2,    2,    0 ),
496              'PEARSON'         => array( 312,    2,    2,    0 ),
497              'RSQ'             => array( 313,    2,    2,    0 ),
498              'STEYX'           => array( 314,    2,    2,    0 ),
499              'SLOPE'           => array( 315,    2,    2,    0 ),
500              'TTEST'           => array( 316,    4,    2,    0 ),
501              'PROB'            => array( 317,   -1,    2,    0 ),
502              'DEVSQ'           => array( 318,   -1,    0,    0 ),
503              'GEOMEAN'         => array( 319,   -1,    0,    0 ),
504              'HARMEAN'         => array( 320,   -1,    0,    0 ),
505              'SUMSQ'           => array( 321,   -1,    0,    0 ),
506              'KURT'            => array( 322,   -1,    0,    0 ),
507              'SKEW'            => array( 323,   -1,    0,    0 ),
508              'ZTEST'           => array( 324,   -1,    0,    0 ),
509              'LARGE'           => array( 325,    2,    0,    0 ),
510              'SMALL'           => array( 326,    2,    0,    0 ),
511              'QUARTILE'        => array( 327,    2,    0,    0 ),
512              'PERCENTILE'      => array( 328,    2,    0,    0 ),
513              'PERCENTRANK'     => array( 329,   -1,    0,    0 ),
514              'MODE'            => array( 330,   -1,    2,    0 ),
515              'TRIMMEAN'        => array( 331,    2,    0,    0 ),
516              'TINV'            => array( 332,    2,    1,    0 ),
517              'CONCATENATE'     => array( 336,   -1,    1,    0 ),
518              'POWER'           => array( 337,    2,    1,    0 ),
519              'RADIANS'         => array( 342,    1,    1,    0 ),
520              'DEGREES'         => array( 343,    1,    1,    0 ),
521              'SUBTOTAL'        => array( 344,   -1,    0,    0 ),
522              'SUMIF'           => array( 345,   -1,    0,    0 ),
523              'COUNTIF'         => array( 346,    2,    0,    0 ),
524              'COUNTBLANK'      => array( 347,    1,    0,    0 ),
525              'ROMAN'           => array( 354,   -1,    1,    0 )
526              );
527    }
528
529    /**
530    * Convert a token to the proper ptg value.
531    *
532    * @access private
533    * @param mixed $token The token to convert.
534    * @return mixed the converted token on success. PEAR_Error if the token
535    *               is not recognized
536    */
537    function _convert($token)
538    {
539        if (preg_match('/^"[^"]{0,255}"$/', $token))
540        {
541            return $this->_convertString($token);
542        }
543        elseif (is_numeric($token))
544        {
545            return $this->_convertNumber($token);
546        }
547        // match references like A1 or $A$1
548        elseif (preg_match('/^\$?([A-Ia-i]?[A-Za-z])\$?(\d+)$/',$token))
549        {
550            return $this->_convertRef2d($token);
551        }
552        // match external references like Sheet1!A1 or Sheet1:Sheet2!A1
553        elseif (preg_match('/^\w+(\:\w+)?\![A-Ia-i]?[A-Za-z](\d+)$/',$token))
554        {
555            return $this->_convertRef3d($token);
556        }
557        // match external references like Sheet1!A1 or Sheet1:Sheet2!A1
558        elseif (preg_match("/^'\w+(\:\w+)?'\![A-Ia-i]?[A-Za-z](\d+)$/",$token))
559        {
560            return $this->_convertRef3d($token);
561        }
562        // match ranges like A1:B2
563        elseif (preg_match('/^(\$)?[A-Ia-i]?[A-Za-z](\$)?(\d+)\:(\$)?[A-Ia-i]?[A-Za-z](\$)?(\d+)$/',$token))
564        {
565            return $this->_convertRange2d($token);
566        }
567        // match ranges like A1..B2
568        elseif (preg_match('/^(\$)?[A-Ia-i]?[A-Za-z](\$)?(\d+)\.\.(\$)?[A-Ia-i]?[A-Za-z](\$)?(\d+)$/',$token))
569        {
570            return $this->_convertRange2d($token);
571        }
572        // match external ranges like Sheet1!A1 or Sheet1:Sheet2!A1:B2
573        elseif (preg_match('/^\w+(\:\w+)?\!([A-Ia-i]?[A-Za-z])?(\d+)\:([A-Ia-i]?[A-Za-z])?(\d+)$/',$token))
574        {
575            return $this->_convertRange3d($token);
576        }
577        // match external ranges like 'Sheet1'!A1 or 'Sheet1:Sheet2'!A1:B2
578        elseif (preg_match("/^'\w+(\:\w+)?'\!([A-Ia-i]?[A-Za-z])?(\d+)\:([A-Ia-i]?[A-Za-z])?(\d+)$/",$token))
579        {
580            return $this->_convertRange3d($token);
581        }
582        elseif (isset($this->ptg[$token])) // operators (including parentheses)
583        {
584            return pack("C", $this->ptg[$token]);
585        }
586        // commented so argument number can be processed correctly. See toReversePolish().
587        /*elseif (preg_match('/[A-Z0-9\xc0-\xdc\.]+/',$token))
588        {
589            return($this->_convertFunction($token,$this->_func_args));
590        }*/
591        // if it's an argument, ignore the token (the argument remains)
592        elseif ($token == 'arg')
593        {
594            return '';
595        }
596        // TODO: use real error codes
597        return $this->raiseError("Unknown token $token");
598    }
599
600    /**
601    * Convert a number token to ptgInt or ptgNum
602    *
603    * @access private
604    * @param mixed $num an integer or double for conversion to its ptg value
605    */
606    function _convertNumber($num)
607    {
608        // Integer in the range 0..2**16-1
609        if ((preg_match('/^\d+$/',$num)) and ($num <= 65535)) {
610            return pack("Cv", $this->ptg['ptgInt'], $num);
611        }
612        else // A float
613        {
614            if ($this->_byte_order) { // if it's Big Endian
615                $num = strrev($num);
616            }
617            return pack("Cd", $this->ptg['ptgNum'], $num);
618        }
619    }
620
621    /**
622    * Convert a string token to ptgStr
623    *
624    * @access private
625    * @param string $string A string for conversion to its ptg value.
626    * @return mixed the converted token on success. PEAR_Error if the string
627    *               is longer than 255 characters.
628    */
629    function _convertString($string)
630    {
631        // chop away beggining and ending quotes
632        $string = substr($string, 1, strlen($string) - 2);
633        if (strlen($string) > 255) {
634            return $this->raiseError("String is too long");
635        }
636        if ($this->_BIFF_version == 0x0500) {
637            return pack("CC", $this->ptg['ptgStr'], strlen($string)).$string;
638        }
639        elseif ($this->_BIFF_version == 0x0600) {
640            $encoding = 0;   // TODO: Unicode support
641            return pack("CCC", $this->ptg['ptgStr'], strlen($string), $encoding).$string;
642        }
643    }
644
645    /**
646    * Convert a function to a ptgFunc or ptgFuncVarV depending on the number of
647    * args that it takes.
648    *
649    * @access private
650    * @param string  $token    The name of the function for convertion to ptg value.
651    * @param integer $num_args The number of arguments the function receives.
652    * @return string The packed ptg for the function
653    */
654    function _convertFunction($token, $num_args)
655    {
656        $args     = $this->_functions[$token][1];
657        $volatile = $this->_functions[$token][3];
658
659        // Fixed number of args eg. TIME($i,$j,$k).
660        if ($args >= 0) {
661            return pack("Cv", $this->ptg['ptgFuncV'], $this->_functions[$token][0]);
662        }
663        // Variable number of args eg. SUM($i,$j,$k, ..).
664        if ($args == -1) {
665            return pack("CCv", $this->ptg['ptgFuncVarV'], $num_args, $this->_functions[$token][0]);
666        }
667    }
668
669    /**
670    * Convert an Excel range such as A1:D4 to a ptgRefV.
671    *
672    * @access private
673    * @param string $range An Excel range in the A1:A2 or A1..A2 format.
674    */
675    function _convertRange2d($range)
676    {
677        $class = 2; // as far as I know, this is magick.
678
679        // Split the range into 2 cell refs
680        if (preg_match('/^([A-Ia-i]?[A-Za-z])(\d+)\:([A-Ia-i]?[A-Za-z])(\d+)$/',$range)) {
681            list($cell1, $cell2) = explode(':', $range);
682        }
683        elseif (preg_match('/^([A-Ia-i]?[A-Za-z])(\d+)\.\.([A-Ia-i]?[A-Za-z])(\d+)$/',$range)) {
684            list($cell1, $cell2) = explode('..', $range);
685
686        }
687        else {
688            // TODO: use real error codes
689            return $this->raiseError("Unknown range separator", 0, PEAR_ERROR_DIE);
690        }
691
692        // Convert the cell references
693        $cell_array1 = $this->_cellToPackedRowcol($cell1);
694        if (PEAR::isError($cell_array1)) {
695            return $cell_array1;
696        }
697        list($row1, $col1) = $cell_array1;
698        $cell_array2 = $this->_cellToPackedRowcol($cell2);
699        if (PEAR::isError($cell_array2)) {
700            return $cell_array2;
701        }
702        list($row2, $col2) = $cell_array2;
703
704        // The ptg value depends on the class of the ptg.
705        if ($class == 0) {
706            $ptgArea = pack("C", $this->ptg['ptgArea']);
707        }
708        elseif ($class == 1) {
709            $ptgArea = pack("C", $this->ptg['ptgAreaV']);
710        }
711        elseif ($class == 2) {
712            $ptgArea = pack("C", $this->ptg['ptgAreaA']);
713        }
714        else {
715            // TODO: use real error codes
716            return $this->raiseError("Unknown class $class", 0, PEAR_ERROR_DIE);
717        }
718        return $ptgArea . $row1 . $row2 . $col1. $col2;
719    }
720
721    /**
722    * Convert an Excel 3d range such as "Sheet1!A1:D4" or "Sheet1:Sheet2!A1:D4" to
723    * a ptgArea3d.
724    *
725    * @access private
726    * @param string $token An Excel range in the Sheet1!A1:A2 format.
727    * @return mixed The packed ptgArea3d token on success, PEAR_Error on failure.
728    */
729    function _convertRange3d($token)
730    {
731        $class = 2; // as far as I know, this is magick.
732
733        // Split the ref at the ! symbol
734        list($ext_ref, $range) = explode('!', $token);
735
736        // Convert the external reference part (different for BIFF8)
737        if ($this->_BIFF_version == 0x0500) {
738            $ext_ref = $this->_packExtRef($ext_ref);
739            if (PEAR::isError($ext_ref)) {
740                return $ext_ref;
741            }
742        }
743        elseif ($this->_BIFF_version == 0x0600) {
744             $ext_ref = $this->_getRefIndex($ext_ref);
745             if (PEAR::isError($ext_ref)) {
746                 return $ext_ref;
747             }
748        }
749
750        // Split the range into 2 cell refs
751        list($cell1, $cell2) = explode(':', $range);
752
753        // Convert the cell references
754        if (preg_match('/^(\$)?[A-Ia-i]?[A-Za-z](\$)?(\d+)$/', $cell1))
755        {
756            $cell_array1 = $this->_cellToPackedRowcol($cell1);
757            if (PEAR::isError($cell_array1)) {
758                return $cell_array1;
759            }
760            list($row1, $col1) = $cell_array1;
761            $cell_array2 = $this->_cellToPackedRowcol($cell2);
762            if (PEAR::isError($cell_array2)) {
763                return $cell_array2;
764            }
765            list($row2, $col2) = $cell_array2;
766        }
767        else { // It's a rows range (like 26:27)
768             $cells_array = $this->_rangeToPackedRange($cell1.':'.$cell2);
769             if (PEAR::isError($cells_array)) {
770                 return $cells_array;
771             }
772             list($row1, $col1, $row2, $col2) = $cells_array;
773        }
774
775        // The ptg value depends on the class of the ptg.
776        if ($class == 0) {
777            $ptgArea = pack("C", $this->ptg['ptgArea3d']);
778        }
779        elseif ($class == 1) {
780            $ptgArea = pack("C", $this->ptg['ptgArea3dV']);
781        }
782        elseif ($class == 2) {
783            $ptgArea = pack("C", $this->ptg['ptgArea3dA']);
784        }
785        else {
786            return $this->raiseError("Unknown class $class", 0, PEAR_ERROR_DIE);
787        }
788
789        return $ptgArea . $ext_ref . $row1 . $row2 . $col1. $col2;
790    }
791
792    /**
793    * Convert an Excel reference such as A1, $B2, C$3 or $D$4 to a ptgRefV.
794    *
795    * @access private
796    * @param string $cell An Excel cell reference
797    * @return string The cell in packed() format with the corresponding ptg
798    */
799    function _convertRef2d($cell)
800    {
801        $class = 2; // as far as I know, this is magick.
802
803        // Convert the cell reference
804        $cell_array = $this->_cellToPackedRowcol($cell);
805        if (PEAR::isError($cell_array)) {
806            return $cell_array;
807        }
808        list($row, $col) = $cell_array;
809
810        // The ptg value depends on the class of the ptg.
811        if ($class == 0) {
812            $ptgRef = pack("C", $this->ptg['ptgRef']);
813        }
814        elseif ($class == 1) {
815            $ptgRef = pack("C", $this->ptg['ptgRefV']);
816        }
817        elseif ($class == 2) {
818            $ptgRef = pack("C", $this->ptg['ptgRefA']);
819        }
820        else {
821            // TODO: use real error codes
822            return $this->raiseError("Unknown class $class");
823        }
824        return $ptgRef.$row.$col;
825    }
826
827    /**
828    * Convert an Excel 3d reference such as "Sheet1!A1" or "Sheet1:Sheet2!A1" to a
829    * ptgRef3d.
830    *
831    * @access private
832    * @param string $cell An Excel cell reference
833    * @return mixed The packed ptgRef3d token on success, PEAR_Error on failure.
834    */
835    function _convertRef3d($cell)
836    {
837        $class = 2; // as far as I know, this is magick.
838
839        // Split the ref at the ! symbol
840        list($ext_ref, $cell) = explode('!', $cell);
841
842        // Convert the external reference part (different for BIFF8)
843        if ($this->_BIFF_version == 0x0500) {
844            $ext_ref = $this->_packExtRef($ext_ref);
845            if (PEAR::isError($ext_ref)) {
846                return $ext_ref;
847            }
848        }
849        elseif ($this->_BIFF_version == 0x0600) {
850            $ext_ref = $this->_getRefIndex($ext_ref);
851            if (PEAR::isError($ext_ref)) {
852                return $ext_ref;
853            }
854        }
855
856        // Convert the cell reference part
857        list($row, $col) = $this->_cellToPackedRowcol($cell);
858
859        // The ptg value depends on the class of the ptg.
860        if ($class == 0) {
861            $ptgRef = pack("C", $this->ptg['ptgRef3d']);
862        }
863        elseif ($class == 1) {
864            $ptgRef = pack("C", $this->ptg['ptgRef3dV']);
865        }
866        elseif ($class == 2) {
867            $ptgRef = pack("C", $this->ptg['ptgRef3dA']);
868        }
869        else {
870            return $this->raiseError("Unknown class $class", 0, PEAR_ERROR_DIE);
871        }
872
873        return $ptgRef . $ext_ref. $row . $col;
874    }
875
876    /**
877    * Convert the sheet name part of an external reference, for example "Sheet1" or
878    * "Sheet1:Sheet2", to a packed structure.
879    *
880    * @access private
881    * @param string $ext_ref The name of the external reference
882    * @return string The reference index in packed() format
883    */
884    function _packExtRef($ext_ref)
885    {
886        $ext_ref = preg_replace("/^'/", '', $ext_ref); // Remove leading  ' if any.
887        $ext_ref = preg_replace("/'$/", '', $ext_ref); // Remove trailing ' if any.
888
889        // Check if there is a sheet range eg., Sheet1:Sheet2.
890        if (preg_match('/:/', $ext_ref))
891        {
892            list($sheet_name1, $sheet_name2) = explode(':', $ext_ref);
893
894            $sheet1 = $this->_getSheetIndex($sheet_name1);
895            if ($sheet1 == -1) {
896                return $this->raiseError("Unknown sheet name $sheet_name1 in formula");
897            }
898            $sheet2 = $this->_getSheetIndex($sheet_name2);
899            if ($sheet2 == -1) {
900                return $this->raiseError("Unknown sheet name $sheet_name2 in formula");
901            }
902
903            // Reverse max and min sheet numbers if necessary
904            if ($sheet1 > $sheet2) {
905                list($sheet1, $sheet2) = array($sheet2, $sheet1);
906            }
907        }
908        else // Single sheet name only.
909        {
910            $sheet1 = $this->_getSheetIndex($ext_ref);
911            if ($sheet1 == -1) {
912                return $this->raiseError("Unknown sheet name $ext_ref in formula");
913            }
914            $sheet2 = $sheet1;
915        }
916
917        // References are stored relative to 0xFFFF.
918        $offset = -1 - $sheet1;
919
920        return pack('vdvv', $offset, 0x00, $sheet1, $sheet2);
921    }
922
923    /**
924    * Look up the REF index that corresponds to an external sheet name
925    * (or range). If it doesn't exist yet add it to the workbook's references
926    * array. It assumes all sheet names given must exist.
927    *
928    * @access private
929    * @param string $ext_ref The name of the external reference
930    * @return mixed The reference index in packed() format on success,
931    *               PEAR_Error on failure
932    */
933    function _getRefIndex($ext_ref)
934    {
935        $ext_ref = preg_replace("/^'/", '', $ext_ref); // Remove leading  ' if any.
936        $ext_ref = preg_replace("/'$/", '', $ext_ref); // Remove trailing ' if any.
937
938        // Check if there is a sheet range eg., Sheet1:Sheet2.
939        if (preg_match('/:/', $ext_ref))
940        {
941            list($sheet_name1, $sheet_name2) = explode(':', $ext_ref);
942
943            $sheet1 = $this->_getSheetIndex($sheet_name1);
944            if ($sheet1 == -1) {
945                return $this->raiseError("Unknown sheet name $sheet_name1 in formula");
946            }
947            $sheet2 = $this->_getSheetIndex($sheet_name2);
948            if ($sheet2 == -1) {
949                return $this->raiseError("Unknown sheet name $sheet_name2 in formula");
950            }
951
952            // Reverse max and min sheet numbers if necessary
953            if ($sheet1 > $sheet2) {
954                list($sheet1, $sheet2) = array($sheet2, $sheet1);
955            }
956        }
957        else // Single sheet name only.
958        {
959            $sheet1 = $this->_getSheetIndex($ext_ref);
960            if ($sheet1 == -1) {
961                return $this->raiseError("Unknown sheet name $ext_ref in formula");
962            }
963            $sheet2 = $sheet1;
964        }
965
966        // assume all references belong to this document
967        $supbook_index = 0x00;
968        $ref = pack('vvv', $supbook_index, $sheet1, $sheet2);
969        $total_references = count($this->_references);
970        $index = -1;
971        for ($i = 0; $i < $total_references; $i++)
972        {
973            if ($ref == $this->_references[$i]) {
974                $index = $i;
975                break;
976            }
977        }
978        // if REF was not found add it to references array
979        if ($index == -1)
980        {
981            $this->_references[$total_references] = $ref;
982            $index = $total_references;
983        }
984
985        return pack('v', $index);
986    }
987
988    /**
989    * Look up the index that corresponds to an external sheet name. The hash of
990    * sheet names is updated by the addworksheet() method of the
991    * Spreadsheet_Excel_Writer_Workbook class.
992    *
993    * @access private
994    * @return integer The sheet index, -1 if the sheet was not found
995    */
996    function _getSheetIndex($sheet_name)
997    {
998        if (!isset($this->_ext_sheets[$sheet_name])) {
999            return -1;
1000        }
1001        else {
1002            return $this->_ext_sheets[$sheet_name];
1003        }
1004    }
1005
1006    /**
1007    * This method is used to update the array of sheet names. It is
1008    * called by the addWorksheet() method of the
1009    * Spreadsheet_Excel_Writer_Workbook class.
1010    *
1011    * @access public
1012    * @see Spreadsheet_Excel_Writer_Workbook::addWorksheet()
1013    * @param string  $name  The name of the worksheet being added
1014    * @param integer $index The index of the worksheet being added
1015    */
1016    function setExtSheet($name, $index)
1017    {
1018        $this->_ext_sheets[$name] = $index;
1019    }
1020
1021    /**
1022    * pack() row and column into the required 3 or 4 byte format.
1023    *
1024    * @access private
1025    * @param string $cell The Excel cell reference to be packed
1026    * @return array Array containing the row and column in packed() format
1027    */
1028    function _cellToPackedRowcol($cell)
1029    {
1030        $cell = strtoupper($cell);
1031        list($row, $col, $row_rel, $col_rel) = $this->_cellToRowcol($cell);
1032        if ($col >= 256) {
1033            return $this->raiseError("Column in: $cell greater than 255");
1034        }
1035        // FIXME: change for BIFF8
1036        if ($row >= 16384) {
1037            return $this->raiseError("Row in: $cell greater than 16384 ");
1038        }
1039
1040        // Set the high bits to indicate if row or col are relative.
1041        if ($this->_BIFF_version == 0x0500) {
1042            $row    |= $col_rel << 14;
1043            $row    |= $row_rel << 15;
1044            $col     = pack('C', $col);
1045        }
1046        elseif ($this->_BIFF_version == 0x0600) {
1047            $col    |= $col_rel << 14;
1048            $col    |= $row_rel << 15;
1049            $col     = pack('v', $col);
1050        }
1051        $row     = pack('v', $row);
1052
1053        return array($row, $col);
1054    }
1055
1056    /**
1057    * pack() row range into the required 3 or 4 byte format.
1058    * Just using maximum col/rows, which is probably not the correct solution
1059    *
1060    * @access private
1061    * @param string $range The Excel range to be packed
1062    * @return array Array containing (row1,col1,row2,col2) in packed() format
1063    */
1064    function _rangeToPackedRange($range)
1065    {
1066        preg_match('/(\$)?(\d+)\:(\$)?(\d+)/', $range, $match);
1067        // return absolute rows if there is a $ in the ref
1068        $row1_rel = empty($match[1]) ? 1 : 0;
1069        $row1     = $match[2];
1070        $row2_rel = empty($match[3]) ? 1 : 0;
1071        $row2     = $match[4];
1072        // Convert 1-index to zero-index
1073        $row1--;
1074        $row2--;
1075        // Trick poor inocent Excel
1076        $col1 = 0;
1077        $col2 = 16383; // FIXME: maximum possible value for Excel 5 (change this!!!)
1078
1079        // FIXME: this changes for BIFF8
1080        if (($row1 >= 16384) or ($row2 >= 16384)) {
1081            return $this->raiseError("Row in: $range greater than 16384 ");
1082        }
1083
1084        // Set the high bits to indicate if rows are relative.
1085        if ($this->_BIFF_version == 0x0500) {
1086            $row1    |= $row1_rel << 14; // FIXME: probably a bug
1087            $row2    |= $row2_rel << 15;
1088            $col1     = pack('C', $col1);
1089            $col2     = pack('C', $col2);
1090        }
1091        elseif ($this->_BIFF_version == 0x0600) {
1092            $col1    |= $row1_rel << 15;
1093            $col2    |= $row2_rel << 15;
1094            $col1     = pack('v', $col1);
1095            $col2     = pack('v', $col2);
1096        }
1097        $row1     = pack('v', $row1);
1098        $row2     = pack('v', $row2);
1099
1100        return array($row1, $col1, $row2, $col2);
1101    }
1102
1103    /**
1104    * Convert an Excel cell reference such as A1 or $B2 or C$3 or $D$4 to a zero
1105    * indexed row and column number. Also returns two (0,1) values to indicate
1106    * whether the row or column are relative references.
1107    *
1108    * @access private
1109    * @param string $cell The Excel cell reference in A1 format.
1110    * @return array
1111    */
1112    function _cellToRowcol($cell)
1113    {
1114        preg_match('/(\$)?([A-I]?[A-Z])(\$)?(\d+)/',$cell,$match);
1115        // return absolute column if there is a $ in the ref
1116        $col_rel = empty($match[1]) ? 1 : 0;
1117        $col_ref = $match[2];
1118        $row_rel = empty($match[3]) ? 1 : 0;
1119        $row     = $match[4];
1120
1121        // Convert base26 column string to a number.
1122        $expn   = strlen($col_ref) - 1;
1123        $col    = 0;
1124        for ($i=0, $tmp_len = strlen($col_ref); $i < $tmp_len; $i++)
1125        {
1126            $col += (ord($col_ref{$i}) - ord('A') + 1) * pow(26, $expn);
1127            $expn--;
1128        }
1129
1130        // Convert 1-index to zero-index
1131        $row--;
1132        $col--;
1133
1134        return array($row, $col, $row_rel, $col_rel);
1135    }
1136
1137    /**
1138    * Advance to the next valid token.
1139    *
1140    * @access private
1141    */
1142    function _advance()
1143    {
1144        $i = $this->_current_char;
1145        // eat up white spaces
1146        if ($i < strlen($this->_formula))
1147        {
1148            while ($this->_formula{$i} == " ") {
1149                $i++;
1150            }
1151            if ($i < strlen($this->_formula) - 1) {
1152                $this->_lookahead = $this->_formula{$i+1};
1153            }
1154            $token = "";
1155        }
1156        while ($i < strlen($this->_formula))
1157        {
1158            $token .= $this->_formula{$i};
1159            if ($i < strlen($this->_formula) - 1) {
1160                $this->_lookahead = $this->_formula{$i+1};
1161            }
1162            else {
1163                $this->_lookahead = '';
1164            }
1165            if ($this->_match($token) != '')
1166            {
1167                //if ($i < strlen($this->_formula) - 1) {
1168                //    $this->_lookahead = $this->_formula{$i+1};
1169                //}
1170                $this->_current_char = $i + 1;
1171                $this->_current_token = $token;
1172                return 1;
1173            }
1174            if ($i < strlen($this->_formula) - 2) {
1175                $this->_lookahead = $this->_formula{$i+2};
1176            }
1177            // if we run out of characters _lookahead becomes empty
1178            else {
1179                $this->_lookahead = '';
1180            }
1181            $i++;
1182        }
1183        //die("Lexical error ".$this->_current_char);
1184    }
1185
1186    /**
1187    * Checks if it's a valid token.
1188    *
1189    * @access private
1190    * @param mixed $token The token to check.
1191    * @return mixed       The checked token or false on failure
1192    */
1193    function _match($token)
1194    {
1195        switch($token)
1196        {
1197            case SPREADSHEET_EXCEL_WRITER_ADD:
1198                return $token;
1199                break;
1200            case SPREADSHEET_EXCEL_WRITER_SUB:
1201                return $token;
1202                break;
1203            case SPREADSHEET_EXCEL_WRITER_MUL:
1204                return $token;
1205                break;
1206            case SPREADSHEET_EXCEL_WRITER_DIV:
1207                return $token;
1208                break;
1209            case SPREADSHEET_EXCEL_WRITER_OPEN:
1210                return $token;
1211                break;
1212            case SPREADSHEET_EXCEL_WRITER_CLOSE:
1213                return $token;
1214                break;
1215            case SPREADSHEET_EXCEL_WRITER_COMA:
1216                return $token;
1217                break;
1218            case SPREADSHEET_EXCEL_WRITER_SEMICOLON:
1219                return $token;
1220                break;
1221            case SPREADSHEET_EXCEL_WRITER_GT:
1222                if ($this->_lookahead == '=') { // it's a GE token
1223                    break;
1224                }
1225                return $token;
1226                break;
1227            case SPREADSHEET_EXCEL_WRITER_LT:
1228                // it's a LE or a NE token
1229                if (($this->_lookahead == '=') or ($this->_lookahead == '>')) {
1230                    break;
1231                }
1232                return $token;
1233                break;
1234            case SPREADSHEET_EXCEL_WRITER_GE:
1235                return $token;
1236                break;
1237            case SPREADSHEET_EXCEL_WRITER_LE:
1238                return $token;
1239                break;
1240            case SPREADSHEET_EXCEL_WRITER_EQ:
1241                return $token;
1242                break;
1243            case SPREADSHEET_EXCEL_WRITER_NE:
1244                return $token;
1245                break;
1246            default:
1247                // if it's a reference
1248                if (preg_match('/^\$?[A-Ia-i]?[A-Za-z]\$?[0-9]+$/',$token) and
1249                   !preg_match('/[0-9]/',$this->_lookahead) and
1250                   ($this->_lookahead != ':') and ($this->_lookahead != '.') and
1251                   ($this->_lookahead != '!'))
1252                {
1253                    return $token;
1254                }
1255                // If it's an external reference (Sheet1!A1 or Sheet1:Sheet2!A1)
1256                elseif (preg_match('/^\w+(\:\w+)?\![A-Ia-i]?[A-Za-z][0-9]+$/',$token) and
1257                       !preg_match('/[0-9]/',$this->_lookahead) and
1258                       ($this->_lookahead != ':') and ($this->_lookahead != '.'))
1259                {
1260                    return $token;
1261                }
1262                // If it's an external reference (Sheet1!A1 or Sheet1:Sheet2!A1)
1263                elseif (preg_match("/^'\w+(\:\w+)?'\![A-Ia-i]?[A-Za-z][0-9]+$/",$token) and
1264                       !preg_match('/[0-9]/',$this->_lookahead) and
1265                       ($this->_lookahead != ':') and ($this->_lookahead != '.'))
1266                {
1267                    return $token;
1268                }
1269                // if it's a range (A1:A2)
1270                elseif (preg_match('/^(\$)?[A-Ia-i]?[A-Za-z](\$)?[0-9]+:(\$)?[A-Ia-i]?[A-Za-z](\$)?[0-9]+$/',$token) and
1271                       !preg_match('/[0-9]/',$this->_lookahead))
1272                {
1273                    return $token;
1274                }
1275                // if it's a range (A1..A2)
1276                elseif (preg_match('/^(\$)?[A-Ia-i]?[A-Za-z](\$)?[0-9]+\.\.(\$)?[A-Ia-i]?[A-Za-z](\$)?[0-9]+$/',$token) and
1277                       !preg_match('/[0-9]/',$this->_lookahead))
1278                {
1279                    return $token;
1280                }
1281                // If it's an external range like Sheet1!A1 or Sheet1:Sheet2!A1:B2
1282                elseif (preg_match('/^\w+(\:\w+)?\!([A-Ia-i]?[A-Za-z])?[0-9]+:([A-Ia-i]?[A-Za-z])?[0-9]+$/',$token) and
1283                       !preg_match('/[0-9]/',$this->_lookahead))
1284                {
1285                    return $token;
1286                }
1287                // If it's an external range like 'Sheet1'!A1 or 'Sheet1:Sheet2'!A1:B2
1288                elseif (preg_match("/^'\w+(\:\w+)?'\!([A-Ia-i]?[A-Za-z])?[0-9]+:([A-Ia-i]?[A-Za-z])?[0-9]+$/",$token) and
1289                       !preg_match('/[0-9]/',$this->_lookahead))
1290                {
1291                    return $token;
1292                }
1293                // If it's a number (check that it's not a sheet name or range)
1294                elseif (is_numeric($token) and
1295                        (!is_numeric($token.$this->_lookahead) or ($this->_lookahead == '')) and
1296                        ($this->_lookahead != '!') and ($this->_lookahead != ':'))
1297                {
1298                    return $token;
1299                }
1300                // If it's a string (of maximum 255 characters)
1301                elseif (preg_match('/^"[^"]{0,255}"$/',$token))
1302                {
1303                    return $token;
1304                }
1305                // if it's a function call
1306                elseif (preg_match('/^[A-Z0-9\xc0-\xdc\.]+$/i',$token) and ($this->_lookahead == '('))
1307                {
1308                    return $token;
1309                }
1310                return '';
1311        }
1312    }
1313
1314    /**
1315    * The parsing method. It parses a formula.
1316    *
1317    * @access public
1318    * @param string $formula The formula to parse, without the initial equal
1319    *                        sign (=).
1320    * @return mixed true on success, PEAR_Error on failure
1321    */
1322    function parse($formula)
1323    {
1324        $this->_current_char = 0;
1325        $this->_formula      = $formula;
1326        $this->_lookahead    = $formula{1};
1327        $this->_advance();
1328        $this->_parse_tree   = $this->_condition();
1329        if (PEAR::isError($this->_parse_tree)) {
1330            return $this->_parse_tree;
1331        }
1332        return true;
1333    }
1334
1335    /**
1336    * It parses a condition. It assumes the following rule:
1337    * Cond -> Expr [(">" | "<") Expr]
1338    *
1339    * @access private
1340    * @return mixed The parsed ptg'd tree on success, PEAR_Error on failure
1341    */
1342    function _condition()
1343    {
1344        $result = $this->_expression();
1345        if (PEAR::isError($result)) {
1346            return $result;
1347        }
1348        if ($this->_current_token == SPREADSHEET_EXCEL_WRITER_LT)
1349        {
1350            $this->_advance();
1351            $result2 = $this->_expression();
1352            if (PEAR::isError($result2)) {
1353                return $result2;
1354            }
1355            $result = $this->_createTree('ptgLT', $result, $result2);
1356        }
1357        elseif ($this->_current_token == SPREADSHEET_EXCEL_WRITER_GT)
1358        {
1359            $this->_advance();
1360            $result2 = $this->_expression();
1361            if (PEAR::isError($result2)) {
1362                return $result2;
1363            }
1364            $result = $this->_createTree('ptgGT', $result, $result2);
1365        }
1366        elseif ($this->_current_token == SPREADSHEET_EXCEL_WRITER_LE)
1367        {
1368            $this->_advance();
1369            $result2 = $this->_expression();
1370            if (PEAR::isError($result2)) {
1371                return $result2;
1372            }
1373            $result = $this->_createTree('ptgLE', $result, $result2);
1374        }
1375        elseif ($this->_current_token == SPREADSHEET_EXCEL_WRITER_GE)
1376        {
1377            $this->_advance();
1378            $result2 = $this->_expression();
1379            if (PEAR::isError($result2)) {
1380                return $result2;
1381            }
1382            $result = $this->_createTree('ptgGE', $result, $result2);
1383        }
1384        elseif ($this->_current_token == SPREADSHEET_EXCEL_WRITER_EQ)
1385        {
1386            $this->_advance();
1387            $result2 = $this->_expression();
1388            if (PEAR::isError($result2)) {
1389                return $result2;
1390            }
1391            $result = $this->_createTree('ptgEQ', $result, $result2);
1392        }
1393        elseif ($this->_current_token == SPREADSHEET_EXCEL_WRITER_NE)
1394        {
1395            $this->_advance();
1396            $result2 = $this->_expression();
1397            if (PEAR::isError($result2)) {
1398                return $result2;
1399            }
1400            $result = $this->_createTree('ptgNE', $result, $result2);
1401        }
1402        return $result;
1403    }
1404
1405    /**
1406    * It parses a expression. It assumes the following rule:
1407    * Expr -> Term [("+" | "-") Term]
1408    *      -> "string"
1409    *      -> "-" Term
1410    *
1411    * @access private
1412    * @return mixed The parsed ptg'd tree on success, PEAR_Error on failure
1413    */
1414    function _expression()
1415    {
1416        // If it's a string return a string node
1417        if (preg_match('/^"[^"]{0,255}"$/', $this->_current_token)) {
1418            $result = $this->_createTree($this->_current_token, '', '');
1419            $this->_advance();
1420            return $result;
1421        }
1422        // catch "-" Term
1423        elseif ($this->_current_token == SPREADSHEET_EXCEL_WRITER_SUB) {
1424            $this->_advance();
1425            $result2 = $this->_expression();
1426            $result = $this->_createTree('ptgUminus', $result2, '');
1427            return $result;
1428        }
1429        $result = $this->_term();
1430        if (PEAR::isError($result)) {
1431            return $result;
1432        }
1433        while (($this->_current_token == SPREADSHEET_EXCEL_WRITER_ADD) or
1434               ($this->_current_token == SPREADSHEET_EXCEL_WRITER_SUB))
1435        {
1436            if ($this->_current_token == SPREADSHEET_EXCEL_WRITER_ADD)
1437            {
1438                $this->_advance();
1439                $result2 = $this->_term();
1440                if (PEAR::isError($result2)) {
1441                    return $result2;
1442                }
1443                $result = $this->_createTree('ptgAdd', $result, $result2);
1444            }
1445            else
1446            {
1447                $this->_advance();
1448                $result2 = $this->_term();
1449                if (PEAR::isError($result2)) {
1450                    return $result2;
1451                }
1452                $result = $this->_createTree('ptgSub', $result, $result2);
1453            }
1454        }
1455        return $result;
1456    }
1457
1458    /**
1459    * This function just introduces a ptgParen element in the tree, so that Excel
1460    * doesn't get confused when working with a parenthesized formula afterwards.
1461    *
1462    * @access private
1463    * @see _fact()
1464    * @return array The parsed ptg'd tree
1465    */
1466    function _parenthesizedExpression()
1467    {
1468        $result = $this->_createTree('ptgParen', $this->_expression(), '');
1469        return $result;
1470    }
1471
1472    /**
1473    * It parses a term. It assumes the following rule:
1474    * Term -> Fact [("*" | "/") Fact]
1475    *
1476    * @access private
1477    * @return mixed The parsed ptg'd tree on success, PEAR_Error on failure
1478    */
1479    function _term()
1480    {
1481        $result = $this->_fact();
1482        if (PEAR::isError($result)) {
1483            return $result;
1484        }
1485        while (($this->_current_token == SPREADSHEET_EXCEL_WRITER_MUL) or
1486               ($this->_current_token == SPREADSHEET_EXCEL_WRITER_DIV))
1487        {
1488            if ($this->_current_token == SPREADSHEET_EXCEL_WRITER_MUL)
1489            {
1490                $this->_advance();
1491                $result2 = $this->_fact();
1492                if (PEAR::isError($result2)) {
1493                    return $result2;
1494                }
1495                $result = $this->_createTree('ptgMul', $result, $result2);
1496            }
1497            else
1498            {
1499                $this->_advance();
1500                $result2 = $this->_fact();
1501                if (PEAR::isError($result2)) {
1502                    return $result2;
1503                }
1504                $result = $this->_createTree('ptgDiv', $result, $result2);
1505            }
1506        }
1507        return $result;
1508    }
1509
1510    /**
1511    * It parses a factor. It assumes the following rule:
1512    * Fact -> ( Expr )
1513    *       | CellRef
1514    *       | CellRange
1515    *       | Number
1516    *       | Function
1517    *
1518    * @access private
1519    * @return mixed The parsed ptg'd tree on success, PEAR_Error on failure
1520    */
1521    function _fact()
1522    {
1523        if ($this->_current_token == SPREADSHEET_EXCEL_WRITER_OPEN)
1524        {
1525            $this->_advance();         // eat the "("
1526            $result = $this->_parenthesizedExpression();
1527            if ($this->_current_token != SPREADSHEET_EXCEL_WRITER_CLOSE) {
1528                return $this->raiseError("')' token expected.");
1529            }
1530            $this->_advance();         // eat the ")"
1531            return $result;
1532        }
1533        // if it's a reference
1534        if (preg_match('/^\$?[A-Ia-i]?[A-Za-z]\$?[0-9]+$/',$this->_current_token))
1535        {
1536            $result = $this->_createTree($this->_current_token, '', '');
1537            $this->_advance();
1538            return $result;
1539        }
1540        // If it's an external reference (Sheet1!A1 or Sheet1:Sheet2!A1)
1541        elseif (preg_match('/^\w+(\:\w+)?\![A-Ia-i]?[A-Za-z][0-9]+$/',$this->_current_token))
1542        {
1543            $result = $this->_createTree($this->_current_token, '', '');
1544            $this->_advance();
1545            return $result;
1546        }
1547        // If it's an external reference (Sheet1!A1 or Sheet1:Sheet2!A1)
1548        elseif (preg_match("/^'\w+(\:\w+)?'\![A-Ia-i]?[A-Za-z][0-9]+$/",$this->_current_token))
1549        {
1550            $result = $this->_createTree($this->_current_token, '', '');
1551            $this->_advance();
1552            return $result;
1553        }
1554        // if it's a range
1555        elseif (preg_match('/^(\$)?[A-Ia-i]?[A-Za-z](\$)?[0-9]+:(\$)?[A-Ia-i]?[A-Za-z](\$)?[0-9]+$/',$this->_current_token) or
1556                preg_match('/^(\$)?[A-Ia-i]?[A-Za-z](\$)?[0-9]+\.\.(\$)?[A-Ia-i]?[A-Za-z](\$)?[0-9]+$/',$this->_current_token))
1557        {
1558            $result = $this->_current_token;
1559            $this->_advance();
1560            return $result;
1561        }
1562        // If it's an external range (Sheet1!A1 or Sheet1!A1:B2)
1563        elseif (preg_match('/^\w+(\:\w+)?\!([A-Ia-i]?[A-Za-z])?[0-9]+:([A-Ia-i]?[A-Za-z])?[0-9]+$/',$this->_current_token))
1564        {
1565            $result = $this->_current_token;
1566            $this->_advance();
1567            return $result;
1568        }
1569        // If it's an external range ('Sheet1'!A1 or 'Sheet1'!A1:B2)
1570        elseif (preg_match("/^'\w+(\:\w+)?'\!([A-Ia-i]?[A-Za-z])?[0-9]+:([A-Ia-i]?[A-Za-z])?[0-9]+$/",$this->_current_token))
1571        {
1572            $result = $this->_current_token;
1573            $this->_advance();
1574            return $result;
1575        }
1576        elseif (is_numeric($this->_current_token))
1577        {
1578            $result = $this->_createTree($this->_current_token, '', '');
1579            $this->_advance();
1580            return $result;
1581        }
1582        // if it's a function call
1583        elseif (preg_match('/^[A-Z0-9\xc0-\xdc\.]+$/i',$this->_current_token))
1584        {
1585            $result = $this->_func();
1586            return $result;
1587        }
1588        return $this->raiseError("Syntax error: ".$this->_current_token.
1589                                 ", lookahead: ".$this->_lookahead.
1590                                 ", current char: ".$this->_current_char);
1591    }
1592
1593    /**
1594    * It parses a function call. It assumes the following rule:
1595    * Func -> ( Expr [,Expr]* )
1596    *
1597    * @access private
1598    * @return mixed The parsed ptg'd tree on success, PEAR_Error on failure
1599    */
1600    function _func()
1601    {
1602        $num_args = 0; // number of arguments received
1603        $function = $this->_current_token;
1604        $this->_advance();
1605        $this->_advance();         // eat the "("
1606        while ($this->_current_token != ')')
1607        {
1608            if ($num_args > 0)
1609            {
1610                if ($this->_current_token == SPREADSHEET_EXCEL_WRITER_COMA ||
1611                    $this->_current_token == SPREADSHEET_EXCEL_WRITER_SEMICOLON)
1612                {
1613                    $this->_advance();  // eat the "," or ";"
1614                }
1615                else {
1616                    return $this->raiseError("Syntax error: comma expected in ".
1617                                      "function $function, arg #{$num_args}");
1618                }
1619                $result2 = $this->_condition();
1620                if (PEAR::isError($result2)) {
1621                    return $result2;
1622                }
1623                $result = $this->_createTree('arg', $result, $result2);
1624            }
1625            else // first argument
1626            {
1627                $result2 = $this->_condition();
1628                if (PEAR::isError($result2)) {
1629                    return $result2;
1630                }
1631                $result = $this->_createTree('arg', '', $result2);
1632            }
1633            $num_args++;
1634        }
1635        $args = $this->_functions[$function][1];
1636        // If fixed number of args eg. TIME($i,$j,$k). Check that the number of args is valid.
1637        if (($args >= 0) and ($args != $num_args)) {
1638            return $this->raiseError("Incorrect number of arguments in function $function() ");
1639        }
1640
1641        $result = $this->_createTree($function, $result, $num_args);
1642        $this->_advance();         // eat the ")"
1643        return $result;
1644    }
1645
1646    /**
1647    * Creates a tree. In fact an array which may have one or two arrays (sub-trees)
1648    * as elements.
1649    *
1650    * @access private
1651    * @param mixed $value The value of this node.
1652    * @param mixed $left  The left array (sub-tree) or a final node.
1653    * @param mixed $right The right array (sub-tree) or a final node.
1654    * @return array A tree
1655    */
1656    function _createTree($value, $left, $right)
1657    {
1658        return array('value' => $value, 'left' => $left, 'right' => $right);
1659    }
1660
1661    /**
1662    * Builds a string containing the tree in reverse polish notation (What you
1663    * would use in a HP calculator stack).
1664    * The following tree:
1665    *
1666    *    +
1667    *   / \
1668    *  2   3
1669    *
1670    * produces: "23+"
1671    *
1672    * The following tree:
1673    *
1674    *    +
1675    *   / \
1676    *  3   *
1677    *     / \
1678    *    6   A1
1679    *
1680    * produces: "36A1*+"
1681    *
1682    * In fact all operands, functions, references, etc... are written as ptg's
1683    *
1684    * @access public
1685    * @param array $tree The optional tree to convert.
1686    * @return string The tree in reverse polish notation
1687    */
1688    function toReversePolish($tree = array())
1689    {
1690        $polish = ""; // the string we are going to return
1691        if (empty($tree)) // If it's the first call use _parse_tree
1692        {
1693            $tree = $this->_parse_tree;
1694        }
1695        if (is_array($tree['left']))
1696        {
1697            $converted_tree = $this->toReversePolish($tree['left']);
1698            if (PEAR::isError($converted_tree)) {
1699                return $converted_tree;
1700            }
1701            $polish .= $converted_tree;
1702        }
1703        elseif ($tree['left'] != '') // It's a final node
1704        {
1705            $converted_tree = $this->_convert($tree['left']);
1706            if (PEAR::isError($converted_tree)) {
1707                return $converted_tree;
1708            }
1709            $polish .= $converted_tree;
1710        }
1711        if (is_array($tree['right']))
1712        {
1713            $converted_tree = $this->toReversePolish($tree['right']);
1714            if (PEAR::isError($converted_tree)) {
1715                return $converted_tree;
1716            }
1717            $polish .= $converted_tree;
1718        }
1719        elseif ($tree['right'] != '') // It's a final node
1720        {
1721            $converted_tree = $this->_convert($tree['right']);
1722            if (PEAR::isError($converted_tree)) {
1723                return $converted_tree;
1724            }
1725            $polish .= $converted_tree;
1726        }
1727        // if it's a function convert it here (so we can set it's arguments)
1728        if (preg_match('/^[A-Z0-9\xc0-\xdc\.]+$/',$tree['value']) and
1729            !preg_match('/^([A-Ia-i]?[A-Za-z])(\d+)$/',$tree['value']) and
1730            !preg_match('/^[A-Ia-i]?[A-Za-z](\d+)\.\.[A-Ia-i]?[A-Za-z](\d+)$/',$tree['value']) and
1731            !is_numeric($tree['value']) and
1732            !isset($this->ptg[$tree['value']]))
1733        {
1734            // left subtree for a function is always an array.
1735            if ($tree['left'] != '') {
1736                $left_tree = $this->toReversePolish($tree['left']);
1737            }
1738            else {
1739                $left_tree = '';
1740            }
1741            if (PEAR::isError($left_tree)) {
1742                return $left_tree;
1743            }
1744            // add it's left subtree and return.
1745            return $left_tree.$this->_convertFunction($tree['value'], $tree['right']);
1746        }
1747        else
1748        {
1749            $converted_tree = $this->_convert($tree['value']);
1750            if (PEAR::isError($converted_tree)) {
1751                return $converted_tree;
1752            }
1753        }
1754        $polish .= $converted_tree;
1755        return $polish;
1756    }
1757}
1758