feat(search): ✨ add proper DB tag searching

www/src/db_handler/db_interface.php

@@ -80,6 +80,16 @@ interface PostdataInterface {
         $order_by = 'path');
     
     public function get_post_markdown($id);
+
+
+    // Returns an array of PostData information
+    // based on the tag search list
+    //
+    // Tag searchlist is comprised of space-separated
+    // tags. Each tag can have a weighting prefix,
+    // and some special tags exist (such as limit:N,
+    // order:S).
+    public function search_posts($taglist);
 }
 
 ?>

www/src/db_handler/mysql_handler.php

@@ -3,23 +3,7 @@
 require_once 'analytics_interface.php';
 require_once 'db_interface.php';
 
-function taglist_escape_tag($tag) {
+require_once 'mysql_taglist_handling.php';
-    return preg_replace_callback('/[\WZ]/', function($match) {
-        return "Z" . ord($match[0]);
-    }, strtolower($tag));
-}
-
-function taglist_to_sql_string($post_tags) {
-    $post_tags = array_unique($post_tags);
-    $post_tags = array_map(function($val) {
-        return taglist_escape_tag($val);
-    }, $post_tags);
-
-    asort($post_tags);
-    $post_tags = join(' ', $post_tags);
-
-    return $post_tags;
-}
 
 class MySQLHandler 
     implements PostdataInterface {
@@ -128,7 +112,7 @@ class MySQLHandler
             $post_path,
             substr_count($post_path, "/"),
             $data['title'],
-            taglist_to_sql_string($post_tags),
+            TagList\create_db_str($post_tags),
             $data['brief'] ?? null
         ];
 
@@ -292,8 +276,8 @@ class MySQLHandler
             'path DESC' => true,
             'created_at' => true,
             'created_at DESC' => true,
-            'modified_at' => true,
+            'updated_at' => true,
-            'modified_at DESC' => true
+            'updated_at DESC' => true
         ];
 
         if(!isset($allowed_ordering[$order_by])) {
@@ -342,6 +326,52 @@ class MySQLHandler
 
         return $data['post_markdown'];
     }
+
+    public function search_posts($taglist) {
+		$qry = "
+			SELECT *
+			FROM posts
+			WHERE MATCH(post_tags) AGAINST (? IN BOOLEAN MODE)
+		";
+
+        $search_data = TagList\create_db_search($taglist);
+
+        $order_by = $search_data['modifiers']['order_by'] ?? 'updated_at';
+        $limit    = intval($search_data['modifiers']['limit'] ?? 20);
+        $offset   = intval($search_data['modifiers']['offset'] ?? 0);
+
+        if($limit > 100) {
+            throw new Exception('Search limit above maximum (max 100 results per search)');
+        }
+
+        $allowed_ordering = [
+            'path' => true,
+            'path DESC' => true,
+            'created_at' => true,
+            'created_at DESC' => true,
+            'updated_at' => true,
+            'updated_at DESC' => true
+        ];
+        // TODO move this to a class var
+
+        if(!isset($allowed_ordering[$order_by])) {
+            throw new Exception('Search order not allowed');
+        }
+        $order_by = 'post_' . $order_by;
+
+		$qry = $qry . " ORDER BY " . $order_by . " LIMIT ? OFFSET ?";
+
+		$search_results = $this->_exec($qry, "sii", $search_data['parameter_string'],
+            $limit, $offset)->fetch_all(MYSQLI_ASSOC);
+
+        $outdata = [];
+        foreach($search_results AS $post_element) {
+            $outdata []= 
+                $this->process_postdata($post_element);
+        }
+
+        return $outdata;
+    }
 }
 
 ?>

www/src/db_handler/mysql_taglist_handling.php

@@ -0,0 +1,76 @@
+<?php
+namespace TagList;
+
+function escape_entry($tag) {
+    return preg_replace_callback('/[\WZ]/', function($match) {
+        return "Z" . ord($match[0]);
+    }, strtolower($tag));
+}
+
+function escape_search_entry($tag) {
+    preg_match("/^([\+\-]?)([^\*]*)(\*?)$/", $tag, $matches);
+
+    if(!isset($matches[1])) {
+        echo "Problem with tag!";
+        var_dump($tag);
+    }
+
+    return $matches[1] . escape_entry($matches[2]) . $matches[3];
+}
+
+function _str_to_raw_taglist($taglist) {
+    $split_list = explode(' ', $taglist);
+
+    $split_list = array_filter($split_list, function($entry) {
+        return !preg_match('/^\s*$/', $entry);
+    });
+
+    return $split_list;
+}
+
+function create_db_str($taglist) {
+    if(gettype($taglist) == 'string') {
+        $taglist = _str_to_raw_taglist($taglist);
+    }
+
+    $taglist = array_unique($taglist);
+    $taglist = array_map(function($val) {
+        return escape_entry($val);
+    }, $taglist);
+
+    asort($taglist);
+    $taglist = join(' ', $taglist);
+
+    return $taglist;
+}
+
+function create_db_search($taglist) {
+    if(gettype($taglist) == 'string') {
+        $taglist = _str_to_raw_taglist($taglist);
+    }
+
+    $search_params = [];
+    $search_modifiers = [];
+
+    foreach($taglist as $tag) {
+        if(preg_match('/^(order|limit):(.*)$/i', $tag, $match)) {
+            $search_modifiers[$match[1]] = $match[2];
+        } else {
+            array_push($search_params, $tag);
+        }
+    }
+
+    $search_params = array_map(function($val) {
+        return escape_search_entry($val);
+    }, $search_params);
+
+    asort($search_params);
+    $search_params = join(' ', $search_params);
+
+    return [
+        'modifiers' => $search_modifiers,
+        'parameter_string' => $search_params
+    ];
+}
+
+?>

www/src/db_handler/post_handler.php

@@ -56,6 +56,17 @@ class PostHandler {
 
         return $out_list;
     }
+
+    public function search_posts($search_query) {
+        $search_results = $this->db->search_posts($search_query);
+
+        $out_list = [];
+        foreach($search_results as $search_result) {
+            array_push($out_list, new Post($this, $search_result, $this->site_defaults));
+        }
+
+        return $out_list;
+    }
 }
 
 ?>