Search engine redesign, first part :

- new table #search to store search rules associated to a search id.

- search rules are not passed through GET anymore, the search array build in
  search.php is serialized in #search table, so no need to rebuild it in
  function include/functions_category.inc.php::category_initialize

- search array build code is improved (efficiency and layout) in search.php

- SQL related to search is build in a dedicated function
  include/functions::get_sql_search_clause

- direct search author:<...>, date_avalaible:<...>, date_creation:<...>,
  keywords:<...> from picture.php are not available anymore. They will come
  back later, with improvement (new design). Same for date_*:<> in calendar
  calendar category.


git-svn-id: http://piwigo.org/svn/trunk@1008 68402e56-0260-453c-a942-63ccdbb3a9ee

3 files changed, 191 insertions, 148 deletions

diff --git a/include/constants.php b/include/constants.php
index bb5a1d926..bf5cfd29c 100644
--- a/include/constants.php
+++ b/include/constants.php
@@ -60,4 +60,5 @@ define('RATE_TABLE', $prefixeTable.'rate');
 define('USER_CACHE_TABLE', $prefixeTable.'user_cache');
 define('CADDIE_TABLE', $prefixeTable.'caddie');
 define('UPGRADE_TABLE', $prefixeTable.'upgrade');
+define('SEARCH_TABLE', $prefixeTable.'search');
 ?>
diff --git a/include/functions.inc.php b/include/functions.inc.php
index 556c62582..f5710bbdd 100644
--- a/include/functions.inc.php
+++ b/include/functions.inc.php
@@ -741,8 +741,8 @@ function l10n($key)
 }
 
 /**
- * returns the corresponding value from $themeconf if existing. Else, the key is
- * returned
+ * returns the corresponding value from $themeconf if existing. Else, the
+ * key is returned
  *
  * @param string key
  * @return string
@@ -753,4 +753,186 @@ function get_themeconf($key)
 
   return $themeconf[$key];
 }
+
+/**
+ * Prepends and appends a string at each value of the given array.
+ *
+ * @param array
+ * @param string prefix to each array values
+ * @param string suffix to each array values
+ */
+function prepend_append_array_items($array, $prepend_str, $append_str)
+{
+  array_walk(
+    $array,
+    create_function('&$s', '$s = "'.$prepend_str.'".$s."'.$append_str.'";')
+    );
+
+  return $array;
+}
+
+/**
+ * returns the SQL clause from a search identifier
+ *
+ * Search rules are stored in search table as a serialized array. This array
+ * need to be transformed into an SQL clause to be used in queries.
+ *
+ * @param int search_id
+ * @return string
+ */
+function get_sql_search_clause($search_id)
+{
+  if (!is_numeric($search_id))
+  {
+    die('Search id must be an integer');
+  }
+  
+  $query = '
+SELECT rules
+  FROM '.SEARCH_TABLE.'
+  WHERE id = '.$_GET['search'].'
+;';
+  list($serialized_rules) = mysql_fetch_row(pwg_query($query));
+  
+  $search = unserialize($serialized_rules);
+
+//   echo '<pre>';
+//   print_r($search);
+//   echo '</pre>';
+
+  // SQL where clauses are stored in $clauses array during query
+  // construction
+  $clauses = array();
+  
+  foreach (array('file','name','comment','keywords','author') as $textfield)
+  {
+    if (isset($search['fields'][$textfield]))
+    {
+      $local_clauses = array();
+      foreach ($search['fields'][$textfield]['words'] as $word)
+      {
+        array_push($local_clauses, $textfield." LIKE '%".$word."%'");
+      }
+
+      // adds brackets around where clauses
+      $local_clauses = prepend_append_array_items($local_clauses, '(', ')');
+
+      array_push(
+        $clauses,
+        implode(
+          ' '.$search['fields'][$textfield]['mode'].' ',
+          $local_clauses
+          )
+        );
+    }
+  }
+  
+  if (isset($search['fields']['allwords']))
+  {
+    $fields = array('file', 'name', 'comment', 'keywords', 'author');
+    // in the OR mode, request bust be :
+    // ((field1 LIKE '%word1%' OR field2 LIKE '%word1%')
+    // OR (field1 LIKE '%word2%' OR field2 LIKE '%word2%'))
+    //
+    // in the AND mode :
+    // ((field1 LIKE '%word1%' OR field2 LIKE '%word1%')
+    // AND (field1 LIKE '%word2%' OR field2 LIKE '%word2%'))
+    $word_clauses = array();
+    foreach ($search['fields']['allwords']['words'] as $word)
+    {
+      $field_clauses = array();
+      foreach ($fields as $field)
+      {
+        array_push($field_clauses, $field." LIKE '%".$word."%'");
+      }
+      // adds brackets around where clauses
+      array_push(
+        $word_clauses,
+        implode(
+          "\n          OR ",
+          $field_clauses
+          )
+        );
+    }
+    
+    array_walk(
+      $word_clauses,
+      create_function('&$s','$s="(".$s.")";')
+      );
+    
+    array_push(
+      $clauses,
+      "\n         ".
+      implode(
+        "\n         ".
+              $search['fields']['allwords']['mode'].
+        "\n         ",
+        $word_clauses
+        )
+      );
+  }
+  
+  foreach (array('date_available', 'date_creation') as $datefield)
+  {
+    if (isset($search['fields'][$datefield]))
+    {
+      array_push(
+        $clauses,
+        $datefield." = '".$search['fields'][$datefield]['date']."'"
+        );
+    }
+    
+    foreach (array('after','before') as $suffix)
+    {
+      $key = $datefield.'-'.$suffix;
+      
+      if (isset($search['fields'][$key]))
+      {
+        array_push(
+          $clauses,
+          
+          $datefield.
+          ($suffix == 'after'             ? ' >' : ' <').
+          ($search['fields'][$key]['inc'] ? '='  : '').
+          " '".$search['fields'][$key]['date']."'"
+          
+          );
+      }
+    }
+  }
+  
+  if (isset($search['fields']['cat']))
+  {
+    if ($search['fields']['cat']['sub_inc'])
+    {
+      // searching all the categories id of sub-categories
+      $cat_ids = get_subcat_ids($search['fields']['cat']['words']);
+    }
+    else
+    {
+      $cat_ids = $search['fields']['cat']['words'];
+    }
+    
+    $local_clause = 'category_id IN ('.implode(',', $cat_ids).')';
+    array_push($clauses, $local_clause);
+  }
+  
+  // adds brackets around where clauses
+  $clauses = prepend_append_array_items($clauses, '(', ')');
+  
+  $where_separator =
+    implode(
+      "\n    ".$search['mode'].' ',
+      $clauses
+      );
+  
+  $search_clause = $where_separator;
+  
+  if (isset($forbidden))
+  {
+    $search_clause.= "\n    AND ".$forbidden;
+  }
+
+  return $search_clause;
+}
 ?>
diff --git a/include/functions_category.inc.php b/include/functions_category.inc.php
index 6b9618db1..c9fee76f0 100644
--- a/include/functions_category.inc.php
+++ b/include/functions_category.inc.php
@@ -103,7 +103,9 @@ function check_cat_id( $cat )
     {
       $page['cat'] = $cat;
     }
-    if ($cat == 'search' and isset($_GET['search']))
+    if ($cat == 'search'
+        and isset($_GET['search'])
+        and is_numeric($_GET['search']))
     {
       $page['cat'] = $cat;
     }
@@ -381,44 +383,6 @@ function initialize_category( $calling_page = 'category' )
       // search result
       if ( $page['cat'] == 'search' )
       {
-        // analyze search string given in URL (created in search.php)
-        $tokens = explode('|', $_GET['search']);
-
-        if (isset($tokens[1]) and $tokens[1] == 'AND')
-        {
-          $search['mode'] = 'AND';
-        }
-        else
-        {
-          $search['mode'] = 'OR';
-        }
-
-        $search_tokens = explode('--', $tokens[0]);
-        foreach ($search_tokens as $search_token)
-        {
-          $tokens = explode(':', $search_token);
-          $field_name = $tokens[0];
-          $field_content = $tokens[1];
-
-          $tokens = explode('~', $tokens[1]);
-          if (isset($tokens[1]))
-          {
-            $search['fields'][$field_name]['mode'] = $tokens[1];
-          }
-          else
-          {
-            $search['fields'][$field_name]['mode'] = '';
-          }
-
-          $search['fields'][$field_name]['words'] = array();
-          $tokens = explode(',', $tokens[0]);
-          foreach ($tokens as $token)
-          {
-            array_push($search['fields'][$field_name]['words'],
-                       htmlentities($token));
-          }
-        }
-        
         $page['title'] = $lang['search_result'];
         if ( $calling_page == 'picture' )
         {
@@ -426,117 +390,13 @@ function initialize_category( $calling_page = 'category' )
           $page['title'].= $_GET['search']."</span>";
         }
 
-        // SQL where clauses are stored in $clauses array during query
-        // construction
-        $clauses = array();
+        $page['where'] = 'WHERE '.get_sql_search_clause($_GET['search']);
         
-        $textfields = array('file', 'name', 'comment', 'keywords', 'author');
-        foreach ($textfields as $textfield)
-        {
-          if (isset($search['fields'][$textfield]))
-          {
-            $local_clauses = array();
-            foreach ($search['fields'][$textfield]['words'] as $word)
-            {
-              array_push($local_clauses, $textfield." LIKE '%".$word."%'");
-            }
-            // adds brackets around where clauses
-            array_walk($local_clauses,create_function('&$s','$s="(".$s.")";'));
-            array_push($clauses,
-                       implode(' '.$search['fields'][$textfield]['mode'].' ',
-                               $local_clauses));
-          }
-        }
-
-        if (isset($search['fields']['allwords']))
-        {
-          $fields = array('file', 'name', 'comment', 'keywords', 'author');
-          // in the OR mode, request bust be :
-          // ((field1 LIKE '%word1%' OR field2 LIKE '%word1%')
-          // OR (field1 LIKE '%word2%' OR field2 LIKE '%word2%'))
-          //
-          // in the AND mode :
-          // ((field1 LIKE '%word1%' OR field2 LIKE '%word1%')
-          // AND (field1 LIKE '%word2%' OR field2 LIKE '%word2%'))
-          $word_clauses = array();
-          foreach ($search['fields']['allwords']['words'] as $word)
-          {
-            $field_clauses = array();
-            foreach ($fields as $field)
-            {
-              array_push($field_clauses, $field." LIKE '%".$word."%'");
-            }
-            // adds brackets around where clauses
-            array_push($word_clauses, implode(' OR ', $field_clauses));
-          }
-          array_walk($word_clauses, create_function('&$s','$s="(".$s.")";'));
-          array_push($clauses,
-                     implode(' '.$search['fields']['allwords']['mode'].' ',
-                               $word_clauses));
-        }
-
-        $datefields = array('date_available', 'date_creation');
-        foreach ($datefields as $datefield)
-        {
-          $key = $datefield;
-          if (isset($search['fields'][$key]))
-          {
-            $local_clause = $datefield." = '";
-            $local_clause.= str_replace('.', '-',
-                                        $search['fields'][$key]['words'][0]);
-            $local_clause.= "'";
-            array_push($clauses, $local_clause);
-          }
-
-          foreach (array('after','before') as $suffix)
-          {
-            $key = $datefield.'-'.$suffix;
-            if (isset($search['fields'][$key]))
-            {
-              $local_clause = $datefield;
-              if ($suffix == 'after')
-              {
-                $local_clause.= ' >';
-              }
-              else
-              {
-                $local_clause.= ' <';
-              }
-              if (isset($search['fields'][$key]['mode'])
-                  and $search['fields'][$key]['mode'] == 'inc')
-              {
-                $local_clause.= '=';
-              }
-              $local_clause.= " '";
-              $local_clause.= str_replace('.', '-',
-                                          $search['fields'][$key]['words'][0]);
-              $local_clause.= "'";
-              array_push($clauses, $local_clause);
-            }
-          }
-        }
-
-        if (isset($search['fields']['cat']))
+        if (isset($forbidden))
         {
-          if ($search['fields']['cat']['mode'] == 'sub_inc')
-          {
-            // searching all the categories id of sub-categories
-            $cat_ids = get_subcat_ids($search['fields']['cat']['words']);
-          }
-          else
-          {
-            $cat_ids = $search['fields']['cat']['words'];
-          }
-          
-          $local_clause = 'category_id IN ('.implode(',', $cat_ids).')';
-          array_push($clauses, $local_clause);
+          $page['where'].= "\n    AND ".$forbidden;
         }
 
-        // adds brackets around where clauses
-        array_walk($clauses, create_function('&$s', '$s = "(".$s.")";'));
-        $page['where'] = 'WHERE '.implode(' '.$search['mode'].' ', $clauses);
-        if ( isset( $forbidden ) ) $page['where'].= ' AND '.$forbidden;
-
         $query = '
 SELECT COUNT(DISTINCT(id)) AS nb_total_images
   FROM '.IMAGES_TABLE.'