PHPTAL-NP-0.7.0/libs/PHPTAL/LoopControler.php

   1 <?php
   2 /* vim: set expandtab tabstop=4 shiftwidth=4: */
   3 //
   4 //  Copyright (c) 2003 Laurent Bedubourg
   5 //
   6 //  This library is free software; you can redistribute it and/or
   7 //  modify it under the terms of the GNU Lesser General Public
   8 //  License as published by the Free Software Foundation; either
   9 //  version 2.1 of the License, or (at your option) any later version.
  10 //
  11 //  This library is distributed in the hope that it will be useful,
  12 //  but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 //  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14 //  Lesser General Public License for more details.
  15 //
  16 //  You should have received a copy of the GNU Lesser General Public
  17 //  License along with this library; if not, write to the Free Software
  18 //  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19 //
  20 //  Authors: Laurent Bedubourg <laurent.bedubourg@free.fr>
  21 //
  22
  23 require_once PT_IP . "/Types/OArray.php";
  24 require_once PT_IP . "/Types/OHash.php";
  25 require_once PT_IP . "/Types/Iterator.php";
  26
  27 /**
  28  * Template loop execution controler.
  29  *
  30  * This object is instantiated by the template on each loop.
  31  *
  32  * LoopControlers accept different types of loop target.
  33  *
  34  * - array
  35  * - objects having an getNewIterator() method returning an Iterator object.
  36  * - Iterator objects which produce isValid(), next(), key() and index()
  37  *   methods.
  38  *   please note that key() return index() for non associative data.
  39  *
  40  * Other types are rejected by the loop controler on runtime producing
  41  * a TypeError exception.
  42  *
  43  * The loop controler install its iterator under the path "repeat/item"
  44  * where "item" is the name of the output var (defined in the template).
  45  *
  46  * Thus, the template can access differents methods of the iterator:
  47  *    repeat/someitem/key
  48  *    repeat/someitem/index
  49  *    repeat/someitem/next
  50  *    repeat/someitem/last
  51  *
  52  * If not all of these methods are implemented in iterators, ask
  53  * iterator maintainers.
  54  *
  55  * @author Laurent Bedubourg <laurent.bedubourg@free.fr>
  56  *
  57  */
  58 class PHPTAL_LoopControler
  59 {
  60     var $_context;
  61     var $_data;
  62     var $_data_name;
  63     var $_iterator;
  64     var $_error;
  65
  66     /**
  67      * Controler constructor.
  68      *
  69      * @param PHPTAL_Context $context
  70      *        The template context.
  71      * @param string $data_name
  72      *        The item data name.
  73      * @param mixed  $data
  74      *        Loop resource.
  75      */
  76     function PHPTAL_LoopControler(&$context, $data_name, $data)
  77     {
  78         $this->_context   =& $context;
  79         $this->_data      =& $data;
  80         $this->_data_name =  $data_name;
  81
  82         // ensure that data is not an error
  83         if (PEAR::isError($data)) {
  84             $this->_error =& $data;
  85             return $data;
  86         }
  87
  88         // accepted objects
  89         //
  90         // - iteratable implementing getNewIterator() method
  91         // - iterator implementing next(), isValid() and index() methods
  92         // - db_result produced by PEAR::DB package
  93         //
  94         if (is_object($data)) {
  95             if (method_exists($data, "getNewIterator")) {
  96
  97                 $this->_iterator =& $data->getNewIterator();
  98
  99             } elseif (is_a("iterator", $data)
 100                       || (method_exists($data, 'next')
 101                           && method_exists($data, 'isValid')
 102                           && method_exists($data, 'index'))) {
 103
 104                 $this->_iterator =& $data;
 105
 106             } elseif (get_class($data) == 'db_result') {
 107
 108                 $this->_iterator = new PHPTAL_DBResultIterator($data);
 109
 110             } else {
 111
 112                 $err = new TypeError("PHPTAL loop controler received a non Iterable object ("
 113                                      . get_class($data) . ")");
 114                 $this->_error =& $err;
 115                 return PEAR::raiseError($err);
 116             }
 117         } elseif (is_array($data)) {
 118             //
 119             // array are accepted thanks to OArrayIterator
 120             //
 121             reset($data);
 122             if (count($data) > 0 && array_key_exists(0, $data)) {
 123                 // echo "OArray::iterator", RxObject::ClassName($data), endl;
 124                 $this->_data = new OArray($data);
 125                 $this->_iterator =& $this->_data->getNewIterator();
 126             } else {
 127                 // echo "OHash::iterator", RxObject::ClassName($data), endl;
 128                 $this->_data = new OHash($data);
 129                 $this->_iterator =& $this->_data->getNewIterator();
 130             }
 131         } else {
 132             $err = new TypeError("phptal loop controler received a non Iterable value ("
 133                                  . gettype($data) . ")");
 134             $this->_error =& $err;
 135             return PEAR::raiseError($err);
 136         }
 137
 138         //
 139         // install loop in repeat context array
 140         //
 141         $repeat =& $this->_context->get("repeat");
 142         if (array_key_exists($this->_data_name, $repeat)) {
 143             unset($repeat[$this->_data_name]);
 144         }
 145         $repeat[$this->_data_name] =& $this;
 146
 147         // $this->_context->setRef($this->_data_name, $temp);
 148         $temp =& $this->_iterator->value();
 149         $this->_context->set($this->_data_name, $temp);
 150         return $temp;
 151     }
 152
 153     /**
 154      * Return current item index.
 155      *
 156      * @return int
 157      */
 158     function index()
 159     {
 160         return $this->_iterator->index();
 161     }
 162
 163     /**
 164      * Return current item key or index for non associative iterators.
 165      *
 166      * @return mixed
 167      */
 168     function key()
 169     {
 170         if (method_exists($this->_iterator, "key")) {
 171             return $this->_iterator->key();
 172         } else {
 173             return $this->_iterator->index();
 174         }
 175     }
 176
 177     /**
 178      * Index is in range(0, length-1), the number in in range(1, length).
 179      *
 180      * @return int
 181      */
 182     function number()
 183     {
 184         return $this->index() + 1;
 185     }
 186
 187     /**
 188      * Return true if index is even.
 189      *
 190      * @return boolean
 191      */
 192     function even()
 193     {
 194         return !$this->odd();
 195     }
 196
 197     /**
 198      * Return true if index is odd.
 199      *
 200      * @return boolean
 201      */
 202     function odd()
 203     {
 204         return ($this->index() % 2);
 205     }
 206
 207     /**
 208      * Return true if at the begining of the loop.
 209      *
 210      * @return boolean
 211      */
 212     function start()
 213     {
 214         return ($this->index() == 0);
 215     }
 216
 217     /**
 218      * Return true if at the end of the loop (no more item).
 219      *
 220      * @return boolean
 221      */
 222     function end()
 223     {
 224         return ($this->length() == $this->number());
 225     }
 226
 227     function isValid()
 228     {
 229         return $this->_iterator->isValid();
 230     }
 231
 232     /**
 233      * Return the length of the data (total number of iterations).
 234      *
 235      * @return int
 236      */
 237     function length()
 238     {
 239         return $this->_data->size();
 240     }
 241
 242     /**
 243      * Retrieve next iterator value.
 244      *
 245      * @return mixed
 246      */
 247     function &next()
 248     {
 249         $temp =& $this->_iterator->next();
 250         if (!$this->_iterator->isValid()) {
 251             return false;
 252         }
 253
 254         // $this->_context->setRef($this->_data_name, $temp);
 255         $this->_context->set($this->_data_name, $temp);
 256         return $temp;
 257     }
 258 };
 259
 260
 261 /**
 262  * Iterator for DB_Result PEAR object.
 263  *
 264  * This class is an implementation of the Iterator Interface
 265  * for DB_Result objects produced by the usage of PEAR::DB package.
 266  *
 267  * @author Laurent Bedubourg <laurent.bedubourg@free.fr>
 268  */
 269 class PHPTAL_DBResultIterator extends Iterator
 270 {
 271     var $_src;
 272     var $_index = -1;
 273     var $_end   = false;
 274     var $_value;
 275
 276     /**
 277      * Iterator constructor.
 278      *
 279      * @param DB_Result $result
 280      *        The query result.
 281      */
 282     function PHPTAL_DBResultIterator(&$result)
 283     {
 284         $this->_src =& $result;
 285         $this->reset();
 286     }
 287
 288     function reset()
 289     {
 290         if ($this->size() == 0) {
 291             $this->_end = true;
 292             return;
 293         }
 294
 295         $this->_index = 0;
 296         $this->_end = false;
 297         unset($this->_value);
 298         $this->_value = $this->_src->fetchRow();
 299     }
 300
 301     /**
 302      * Return the number of rows in this result.
 303      *
 304      * @return int
 305      */
 306     function size()
 307     {
 308         if (!isset($this->_size)) {
 309             $this->_size = $this->_src->numRows();
 310         }
 311         return $this->_size;
 312     }
 313
 314     /**
 315      * Returns true if end of iterator has not been reached yet.
 316      */
 317     function isValid()
 318     {
 319         return !$this->_end;
 320     }
 321
 322     /**
 323      * Return the next row in this result.
 324      *
 325      * This method calls fetchRow() on the DB_Result, the return type depends
 326      * of the DB_result->fetchmod. Please specify it before executing the
 327      * template.
 328      *
 329      * @return mixed
 330      */
 331     function &next()
 332     {
 333         if ($this->_end || ++ $this->_index >= $this->size()) {
 334             $this->_end = true;
 335             return false;
 336         }
 337
 338         unset($this->_value);
 339         $this->_value = $this->_src->fetchRow();
 340         return $this->_value;
 341     }
 342
 343     /**
 344      * Return current row.
 345      *
 346      * @return mixed
 347      */
 348     function &value()
 349     {
 350         return $this->_value;
 351     }
 352
 353     /**
 354      * Return current row index in resultset.
 355      *
 356      * @return int
 357      */
 358     function index()
 359     {
 360         return $this->_index;
 361     }
 362 }
 363
 364 ?>