splitbrain /
dokuwiki
Complex classes like Search often do a lot of different things. To break such a class down, we need to identify a cohesive component within that class. A common approach to find such a component is to look for fields/methods that share the same prefixes, or suffixes. You can also have a look at the cohesion graph to spot any un-connected, or weakly-connected components.
Once you have determined the fields that belong together, you can apply the Extract Class refactoring. If the component makes sense as a sub-class, Extract Subclass is also a candidate, and is often faster.
While breaking up the class, it is a good idea to analyze how other classes use Search, and based on these observations, apply Extract Interface, too.
| 1 | <?php |
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| 7 | class Search extends Ui |
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| 8 | { |
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| 9 | protected $query; |
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| 10 | protected $parsedQuery; |
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| 11 | protected $searchState; |
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| 12 | protected $pageLookupResults = array(); |
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| 13 | protected $fullTextResults = array(); |
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| 14 | protected $highlight = array(); |
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| 15 | |||
| 16 | /** |
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| 17 | * Search constructor. |
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| 18 | * |
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| 19 | * @param array $pageLookupResults pagename lookup results in the form [pagename => pagetitle] |
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| 20 | * @param array $fullTextResults fulltext search results in the form [pagename => #hits] |
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| 21 | * @param array $highlight array of strings to be highlighted |
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| 22 | */ |
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| 23 | public function __construct(array $pageLookupResults, array $fullTextResults, $highlight) |
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| 24 | { |
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| 25 | global $QUERY; |
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| 26 | $Indexer = idx_get_indexer(); |
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| 27 | |||
| 28 | $this->query = $QUERY; |
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| 29 | $this->parsedQuery = ft_queryParser($Indexer, $QUERY); |
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| 30 | $this->searchState = new SearchState($this->parsedQuery); |
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| 31 | |||
| 32 | $this->pageLookupResults = $pageLookupResults; |
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| 33 | $this->fullTextResults = $fullTextResults; |
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| 34 | $this->highlight = $highlight; |
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| 35 | } |
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| 36 | |||
| 37 | /** |
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| 38 | * display the search result |
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| 39 | * |
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| 40 | * @return void |
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| 41 | */ |
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| 42 | public function show() |
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| 56 | |||
| 57 | /** |
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| 58 | * Get a form which can be used to adjust/refine the search |
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| 59 | * |
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| 60 | * @param string $query |
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| 61 | * |
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| 62 | * @return string |
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| 63 | */ |
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| 64 | protected function getSearchFormHTML($query) |
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| 93 | |||
| 94 | /** |
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| 95 | * Add elements to adjust how the results are sorted |
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| 96 | * |
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| 97 | * @param Form $searchForm |
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| 98 | */ |
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| 99 | protected function addSortTool(Form $searchForm) |
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| 148 | |||
| 149 | /** |
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| 150 | * Check if the query is simple enough to modify its namespace limitations without breaking the rest of the query |
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| 151 | * |
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| 152 | * @param array $parsedQuery |
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| 153 | * |
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| 154 | * @return bool |
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| 155 | */ |
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| 156 | protected function isNamespaceAssistanceAvailable(array $parsedQuery) { |
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| 163 | |||
| 164 | /** |
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| 165 | * Check if the query is simple enough to modify the fragment search behavior without breaking the rest of the query |
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| 166 | * |
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| 167 | * @param array $parsedQuery |
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| 168 | * |
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| 169 | * @return bool |
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| 170 | */ |
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| 171 | protected function isFragmentAssistanceAvailable(array $parsedQuery) { |
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| 182 | |||
| 183 | /** |
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| 184 | * Add the elements to be used for search assistance |
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| 185 | * |
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| 186 | * @param Form $searchForm |
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| 187 | */ |
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| 188 | protected function addSearchAssistanceElements(Form $searchForm) |
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| 189 | { |
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| 190 | $searchForm->addTagOpen('div') |
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| 191 | ->addClass('advancedOptions') |
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| 192 | ->attr('style', 'display: none;') |
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| 193 | ->attr('aria-hidden', 'true'); |
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| 194 | |||
| 195 | $this->addFragmentBehaviorLinks($searchForm); |
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| 196 | $this->addNamespaceSelector($searchForm); |
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| 197 | $this->addDateSelector($searchForm); |
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| 198 | $this->addSortTool($searchForm); |
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| 199 | |||
| 200 | $searchForm->addTagClose('div'); |
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| 201 | } |
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| 202 | |||
| 203 | /** |
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| 204 | * Add the elements to adjust the fragment search behavior |
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| 205 | * |
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| 206 | * @param Form $searchForm |
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| 207 | */ |
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| 208 | protected function addFragmentBehaviorLinks(Form $searchForm) |
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| 209 | { |
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| 210 | if (!$this->isFragmentAssistanceAvailable($this->parsedQuery)) { |
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| 211 | return; |
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| 212 | } |
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| 213 | global $lang; |
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| 214 | |||
| 215 | $options = [ |
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| 216 | 'exact' => [ |
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| 217 | 'label' => $lang['search_exact_match'], |
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| 218 | 'and' => array_map(function ($term) { |
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| 219 | return trim($term, '*'); |
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| 220 | }, $this->parsedQuery['and']), |
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| 221 | 'not' => array_map(function ($term) { |
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| 222 | return trim($term, '*'); |
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| 223 | }, $this->parsedQuery['not']), |
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| 224 | ], |
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| 225 | 'starts' => [ |
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| 226 | 'label' => $lang['search_starts_with'], |
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| 227 | 'and' => array_map(function ($term) { |
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| 228 | return trim($term, '*') . '*'; |
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| 229 | }, $this->parsedQuery['and']), |
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| 230 | 'not' => array_map(function ($term) { |
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| 231 | return trim($term, '*') . '*'; |
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| 232 | }, $this->parsedQuery['not']), |
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| 233 | ], |
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| 234 | 'ends' => [ |
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| 235 | 'label' => $lang['search_ends_with'], |
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| 236 | 'and' => array_map(function ($term) { |
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| 237 | return '*' . trim($term, '*'); |
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| 238 | }, $this->parsedQuery['and']), |
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| 239 | 'not' => array_map(function ($term) { |
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| 240 | return '*' . trim($term, '*'); |
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| 241 | }, $this->parsedQuery['not']), |
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| 242 | ], |
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| 243 | 'contains' => [ |
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| 244 | 'label' => $lang['search_contains'], |
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| 245 | 'and' => array_map(function ($term) { |
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| 246 | return '*' . trim($term, '*') . '*'; |
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| 247 | }, $this->parsedQuery['and']), |
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| 248 | 'not' => array_map(function ($term) { |
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| 249 | return '*' . trim($term, '*') . '*'; |
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| 250 | }, $this->parsedQuery['not']), |
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| 251 | ] |
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| 252 | ]; |
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| 253 | |||
| 254 | // detect current |
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| 255 | $activeOption = 'custom'; |
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| 256 | foreach ($options as $key => $option) { |
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| 257 | if ($this->parsedQuery['and'] === $option['and']) { |
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| 258 | $activeOption = $key; |
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| 259 | } |
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| 260 | } |
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| 261 | if ($activeOption === 'custom') { |
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| 262 | $options = array_merge(['custom' => [ |
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| 263 | 'label' => $lang['search_custom_match'], |
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| 264 | ]], $options); |
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| 265 | } |
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| 266 | |||
| 267 | $searchForm->addTagOpen('div')->addClass('toggle')->attr('aria-haspopup', 'true'); |
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| 268 | // render current |
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| 269 | $currentWrapper = $searchForm->addTagOpen('div')->addClass('current'); |
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| 270 | if ($activeOption !== 'exact') { |
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| 271 | $currentWrapper->addClass('changed'); |
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| 272 | } |
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| 273 | $searchForm->addHTML($options[$activeOption]['label']); |
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| 274 | $searchForm->addTagClose('div'); |
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| 275 | |||
| 276 | // render options list |
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| 277 | $searchForm->addTagOpen('ul')->attr('aria-expanded', 'false'); |
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| 278 | |||
| 279 | foreach ($options as $key => $option) { |
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| 280 | $listItem = $searchForm->addTagOpen('li'); |
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| 281 | |||
| 282 | if ($key === $activeOption) { |
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| 283 | $listItem->addClass('active'); |
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| 284 | $searchForm->addHTML($option['label']); |
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| 285 | } else { |
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| 286 | $link = $this->searchState |
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| 287 | ->withFragments($option['and'], $option['not']) |
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| 288 | ->getSearchLink($option['label']) |
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| 289 | ; |
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| 290 | $searchForm->addHTML($link); |
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| 291 | } |
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| 292 | $searchForm->addTagClose('li'); |
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| 293 | } |
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| 294 | $searchForm->addTagClose('ul'); |
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| 295 | |||
| 296 | $searchForm->addTagClose('div'); |
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| 297 | |||
| 298 | // render options list |
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| 299 | } |
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| 300 | |||
| 301 | /** |
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| 302 | * Add the elements for the namespace selector |
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| 303 | * |
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| 304 | * @param Form $searchForm |
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| 305 | */ |
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| 306 | protected function addNamespaceSelector(Form $searchForm) |
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| 307 | { |
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| 308 | if (!$this->isNamespaceAssistanceAvailable($this->parsedQuery)) { |
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| 309 | return; |
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| 310 | } |
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| 311 | |||
| 312 | global $lang; |
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| 313 | |||
| 314 | $baseNS = empty($this->parsedQuery['ns']) ? '' : $this->parsedQuery['ns'][0]; |
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| 315 | $extraNS = $this->getAdditionalNamespacesFromResults($baseNS); |
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| 316 | |||
| 317 | $searchForm->addTagOpen('div')->addClass('toggle')->attr('aria-haspopup', 'true'); |
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| 318 | // render current |
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| 319 | $currentWrapper = $searchForm->addTagOpen('div')->addClass('current'); |
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| 320 | if ($baseNS) { |
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| 321 | $currentWrapper->addClass('changed'); |
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| 322 | $searchForm->addHTML('@' . $baseNS); |
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| 323 | } else { |
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| 324 | $searchForm->addHTML($lang['search_any_ns']); |
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| 325 | } |
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| 326 | $searchForm->addTagClose('div'); |
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| 327 | |||
| 328 | // render options list |
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| 329 | $searchForm->addTagOpen('ul')->attr('aria-expanded', 'false'); |
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| 330 | |||
| 331 | $listItem = $searchForm->addTagOpen('li'); |
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| 332 | if ($baseNS) { |
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| 333 | $listItem->addClass('active'); |
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| 334 | $link = $this->searchState->withNamespace('')->getSearchLink($lang['search_any_ns']); |
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| 335 | $searchForm->addHTML($link); |
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| 336 | } else { |
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| 337 | $searchForm->addHTML($lang['search_any_ns']); |
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| 338 | } |
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| 339 | $searchForm->addTagClose('li'); |
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| 340 | |||
| 341 | foreach ($extraNS as $ns => $count) { |
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| 342 | $listItem = $searchForm->addTagOpen('li'); |
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| 343 | $label = $ns . ($count ? " <bdi>($count)</bdi>" : ''); |
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| 344 | |||
| 345 | if ($ns === $baseNS) { |
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| 346 | $listItem->addClass('active'); |
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| 347 | $searchForm->addHTML($label); |
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| 348 | } else { |
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| 349 | $link = $this->searchState->withNamespace($ns)->getSearchLink($label); |
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| 350 | $searchForm->addHTML($link); |
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| 351 | } |
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| 352 | $searchForm->addTagClose('li'); |
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| 353 | } |
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| 354 | $searchForm->addTagClose('ul'); |
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| 355 | |||
| 356 | $searchForm->addTagClose('div'); |
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| 357 | |||
| 358 | } |
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| 359 | |||
| 360 | /** |
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| 361 | * Parse the full text results for their top namespaces below the given base namespace |
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| 362 | * |
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| 363 | * @param string $baseNS the namespace within which was searched, empty string for root namespace |
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| 364 | * |
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| 365 | * @return array an associative array with namespace => #number of found pages, sorted descending |
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| 366 | */ |
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| 367 | protected function getAdditionalNamespacesFromResults($baseNS) |
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| 368 | { |
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| 369 | $namespaces = []; |
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| 370 | $baseNSLength = strlen($baseNS); |
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| 371 | foreach ($this->fullTextResults as $page => $numberOfHits) { |
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| 372 | $namespace = getNS($page); |
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| 373 | if (!$namespace) { |
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| 374 | continue; |
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| 375 | } |
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| 376 | if ($namespace === $baseNS) { |
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| 377 | continue; |
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| 378 | } |
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| 379 | $firstColon = strpos((string)$namespace, ':', $baseNSLength + 1) ?: strlen($namespace); |
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| 380 | $subtopNS = substr($namespace, 0, $firstColon); |
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| 381 | if (empty($namespaces[$subtopNS])) { |
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| 382 | $namespaces[$subtopNS] = 0; |
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| 383 | } |
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| 384 | $namespaces[$subtopNS] += 1; |
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| 385 | } |
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| 386 | ksort($namespaces); |
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| 387 | arsort($namespaces); |
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| 388 | return $namespaces; |
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| 389 | } |
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| 390 | |||
| 391 | /** |
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| 392 | * @ToDo: custom date input |
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| 393 | * |
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| 394 | * @param Form $searchForm |
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| 395 | */ |
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| 396 | protected function addDateSelector(Form $searchForm) |
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| 397 | { |
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| 398 | global $INPUT, $lang; |
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| 399 | |||
| 400 | $options = [ |
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| 401 | 'any' => [ |
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| 402 | 'before' => false, |
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| 403 | 'after' => false, |
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| 404 | 'label' => $lang['search_any_time'], |
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| 405 | ], |
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| 406 | 'week' => [ |
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| 407 | 'before' => false, |
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| 408 | 'after' => '1 week ago', |
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| 409 | 'label' => $lang['search_past_7_days'], |
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| 410 | ], |
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| 411 | 'month' => [ |
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| 412 | 'before' => false, |
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| 413 | 'after' => '1 month ago', |
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| 414 | 'label' => $lang['search_past_month'], |
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| 415 | ], |
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| 416 | 'year' => [ |
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| 417 | 'before' => false, |
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| 418 | 'after' => '1 year ago', |
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| 419 | 'label' => $lang['search_past_year'], |
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| 420 | ], |
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| 421 | ]; |
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| 422 | $activeOption = 'any'; |
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| 423 | foreach ($options as $key => $option) { |
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| 424 | if ($INPUT->str('min') === $option['after']) { |
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| 425 | $activeOption = $key; |
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| 426 | break; |
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| 427 | } |
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| 428 | } |
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| 429 | |||
| 430 | $searchForm->addTagOpen('div')->addClass('toggle')->attr('aria-haspopup', 'true'); |
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| 431 | // render current |
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| 432 | $currentWrapper = $searchForm->addTagOpen('div')->addClass('current'); |
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| 433 | if ($INPUT->has('max') || $INPUT->has('min')) { |
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| 434 | $currentWrapper->addClass('changed'); |
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| 435 | } |
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| 436 | $searchForm->addHTML($options[$activeOption]['label']); |
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| 437 | $searchForm->addTagClose('div'); |
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| 438 | |||
| 439 | // render options list |
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| 440 | $searchForm->addTagOpen('ul')->attr('aria-expanded', 'false'); |
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| 441 | |||
| 442 | foreach ($options as $key => $option) { |
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| 443 | $listItem = $searchForm->addTagOpen('li'); |
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| 444 | |||
| 445 | if ($key === $activeOption) { |
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| 446 | $listItem->addClass('active'); |
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| 447 | $searchForm->addHTML($option['label']); |
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| 448 | } else { |
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| 449 | $link = $this->searchState |
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| 450 | ->withTimeLimitations($option['after'], $option['before']) |
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| 451 | ->getSearchLink($option['label']) |
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| 452 | ; |
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| 453 | $searchForm->addHTML($link); |
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| 454 | } |
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| 455 | $searchForm->addTagClose('li'); |
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| 456 | } |
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| 457 | $searchForm->addTagClose('ul'); |
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| 458 | |||
| 459 | $searchForm->addTagClose('div'); |
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| 460 | } |
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| 461 | |||
| 462 | |||
| 463 | /** |
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| 464 | * Build the intro text for the search page |
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| 465 | * |
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| 466 | * @param string $query the search query |
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| 467 | * |
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| 468 | * @return string |
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| 469 | */ |
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| 470 | protected function getSearchIntroHTML($query) |
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| 471 | { |
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| 472 | global $lang; |
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| 473 | |||
| 474 | $intro = p_locale_xhtml('searchpage'); |
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| 475 | |||
| 476 | $queryPagename = $this->createPagenameFromQuery($this->parsedQuery); |
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| 477 | $createQueryPageLink = html_wikilink($queryPagename . '?do=edit', $queryPagename); |
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| 478 | |||
| 479 | $pagecreateinfo = ''; |
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| 480 | if (auth_quickaclcheck($queryPagename) >= AUTH_CREATE) { |
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| 481 | $pagecreateinfo = sprintf($lang['searchcreatepage'], $createQueryPageLink); |
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| 482 | } |
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| 483 | $intro = str_replace( |
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| 484 | array('@QUERY@', '@SEARCH@', '@CREATEPAGEINFO@'), |
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| 485 | array(hsc(rawurlencode($query)), hsc($query), $pagecreateinfo), |
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| 486 | $intro |
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| 487 | ); |
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| 488 | |||
| 489 | return $intro; |
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| 490 | } |
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| 491 | |||
| 492 | /** |
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| 493 | * Create a pagename based the parsed search query |
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| 494 | * |
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| 495 | * @param array $parsedQuery |
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| 496 | * |
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| 497 | * @return string pagename constructed from the parsed query |
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| 498 | */ |
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| 499 | protected function createPagenameFromQuery($parsedQuery) |
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| 500 | { |
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| 501 | $pagename = ''; |
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| 502 | if (!empty($parsedQuery['ns'])) { |
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| 503 | $pagename .= cleanID($parsedQuery['ns'][0]); |
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| 504 | } |
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| 505 | $pagename .= ':' . cleanID(implode(' ' , $parsedQuery['highlight'])); |
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| 506 | return $pagename; |
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| 507 | } |
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| 508 | |||
| 509 | /** |
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| 510 | * Build HTML for a list of pages with matching pagenames |
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| 511 | * |
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| 512 | * @param array $data search results |
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| 513 | * |
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| 514 | * @return string |
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| 515 | */ |
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| 516 | protected function getPageLookupHTML($data) |
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| 517 | { |
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| 518 | if (empty($data)) { |
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| 519 | return ''; |
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| 520 | } |
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| 521 | |||
| 522 | global $lang; |
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| 523 | |||
| 524 | $html = '<div class="search_quickresult">'; |
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| 525 | $html .= '<h2>' . $lang['quickhits'] . ':</h2>'; |
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| 526 | $html .= '<ul class="search_quickhits">'; |
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| 527 | foreach ($data as $id => $title) { |
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| 528 | $name = null; |
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| 529 | if (!useHeading('navigation') && $ns = getNS($id)) { |
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| 530 | $name = shorten(noNS($id), ' (' . $ns . ')', 30); |
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| 531 | } |
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| 532 | $link = html_wikilink(':' . $id, $name); |
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| 533 | $eventData = [ |
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| 534 | 'listItemContent' => [$link], |
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| 535 | 'page' => $id, |
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| 536 | ]; |
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| 537 | trigger_event('SEARCH_RESULT_PAGELOOKUP', $eventData); |
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| 538 | $html .= '<li>' . implode('', $eventData['listItemContent']) . '</li>'; |
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| 539 | } |
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| 540 | $html .= '</ul> '; |
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| 541 | //clear float (see http://www.complexspiral.com/publications/containing-floats/) |
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| 542 | $html .= '<div class="clearer"></div>'; |
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| 543 | $html .= '</div>'; |
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| 544 | |||
| 545 | return $html; |
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| 546 | } |
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| 547 | |||
| 548 | /** |
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| 549 | * Build HTML for fulltext search results or "no results" message |
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| 550 | * |
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| 551 | * @param array $data the results of the fulltext search |
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| 552 | * @param array $highlight the terms to be highlighted in the results |
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| 553 | * |
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| 554 | * @return string |
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| 555 | */ |
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| 556 | protected function getFulltextResultsHTML($data, $highlight) |
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| 557 | { |
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| 558 | global $lang; |
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| 559 | |||
| 560 | if (empty($data)) { |
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| 561 | return '<div class="nothing">' . $lang['nothingfound'] . '</div>'; |
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| 562 | } |
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| 563 | |||
| 564 | $html = '<div class="search_fulltextresult">'; |
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| 565 | $html .= '<h2>' . $lang['search_fullresults'] . ':</h2>'; |
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| 566 | |||
| 567 | $html .= '<dl class="search_results">'; |
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| 568 | $num = 0; |
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| 569 | $position = 0; |
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| 570 | |||
| 571 | foreach ($data as $id => $cnt) { |
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| 572 | $position += 1; |
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| 573 | $resultLink = html_wikilink(':' . $id, null, $highlight); |
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| 574 | |||
| 575 | $resultHeader = [$resultLink]; |
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| 576 | |||
| 577 | |||
| 578 | $restrictQueryToNSLink = $this->restrictQueryToNSLink(getNS($id)); |
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| 579 | if ($restrictQueryToNSLink) { |
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| 580 | $resultHeader[] = $restrictQueryToNSLink; |
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| 581 | } |
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| 582 | |||
| 583 | $resultBody = []; |
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| 584 | $mtime = filemtime(wikiFN($id)); |
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| 585 | $lastMod = '<span class="lastmod">' . $lang['lastmod'] . '</span> '; |
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| 586 | $lastMod .= '<time datetime="' . date_iso8601($mtime) . '" title="'.dformat($mtime).'">' . dformat($mtime, '%f') . '</time>'; |
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| 587 | $resultBody['meta'] = $lastMod; |
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| 588 | if ($cnt !== 0) { |
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| 589 | $num++; |
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| 590 | $hits = '<span class="hits">' . $cnt . ' ' . $lang['hits'] . '</span>, '; |
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| 591 | $resultBody['meta'] = $hits . $resultBody['meta']; |
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| 592 | if ($num <= FT_SNIPPET_NUMBER) { // create snippets for the first number of matches only |
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| 593 | $resultBody['snippet'] = ft_snippet($id, $highlight); |
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| 594 | } |
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| 595 | } |
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| 596 | |||
| 597 | $eventData = [ |
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| 598 | 'resultHeader' => $resultHeader, |
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| 599 | 'resultBody' => $resultBody, |
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| 600 | 'page' => $id, |
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| 601 | 'position' => $position, |
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| 602 | ]; |
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| 603 | trigger_event('SEARCH_RESULT_FULLPAGE', $eventData); |
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| 604 | $html .= '<div class="search_fullpage_result">'; |
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| 605 | $html .= '<dt>' . implode(' ', $eventData['resultHeader']) . '</dt>'; |
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| 606 | foreach ($eventData['resultBody'] as $class => $htmlContent) { |
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| 607 | $html .= "<dd class=\"$class\">$htmlContent</dd>"; |
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| 608 | } |
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| 609 | $html .= '</div>'; |
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| 610 | } |
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| 611 | $html .= '</dl>'; |
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| 612 | |||
| 613 | $html .= '</div>'; |
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| 614 | |||
| 615 | return $html; |
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| 616 | } |
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| 617 | |||
| 618 | /** |
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| 619 | * create a link to restrict the current query to a namespace |
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| 620 | * |
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| 621 | * @param false|string $ns the namespace to which to restrict the query |
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| 622 | * |
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| 623 | * @return false|string |
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| 624 | */ |
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| 625 | protected function restrictQueryToNSLink($ns) |
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| 640 | } |
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| 641 |
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Let’s take a look at an example:
In the above example, the authenticate() method works fine as long as you just pass instances of MyUser. However, if you now also want to pass a different sub-classes of User which does not have a getDisplayName() method, the code will break.
Available Fixes
Change the type-hint for the parameter:
Add an additional type-check:
Add the method to the parent class: