make it simple, but not simpler

12 files changed, 681 insertions, 220 deletions

diff --git a/lib/admin.php b/lib/admin.php
index 91aa620..116ee3c 100644
--- a/lib/admin.php
+++ b/lib/admin.php
@@ -1,55 +1,51 @@
 <?php
 
-class admin {
+require_once 'lib/stored_config.php';
 
-    const SESSION_TIMEOUT = 86400 * 14;
-    const COOKIE_NAME = 'admin_key';
+const ADMIN_SESSION_TIMEOUT = 86400 * 14;
+const ADMIN_COOKIE_NAME = 'admin_key';
 
-    protected static ?bool $isAdmin = null;
-
-    public static function isAdmin(): bool {
-        if (is_null(self::$isAdmin))
-            self::$isAdmin = self::_verifyKey();
-        return self::$isAdmin;
-    }
-
-    protected static function _verifyKey(): bool {
-        if (isset($_COOKIE[self::COOKIE_NAME])) {
-            $cookie = (string)$_COOKIE[self::COOKIE_NAME];
-            if ($cookie !== self::getKey())
-                self::unsetCookie();
-            return true;
-        }
-        return false;
-    }
+function is_admin(): bool {
+    static $is_admin = null;
+    if (is_null($is_admin))
+        $is_admin = _admin_verify_key();
+    return $is_admin;
+}
 
-    public static function checkPassword(string $pwd): bool {
-        return salt_password($pwd) === config::get('admin_pwd');
+function _admin_verify_key(): bool {
+    if (isset($_COOKIE[ADMIN_COOKIE_NAME])) {
+        $cookie = (string)$_COOKIE[ADMIN_COOKIE_NAME];
+        if ($cookie !== _admin_get_key())
+            admin_unset_cookie();
+        return true;
     }
+    return false;
+}
 
-    protected static function getKey(): string {
-        global $config;
-        $admin_pwd_hash = config::get('admin_pwd');
-        return salt_password("$admin_pwd_hash|{$_SERVER['REMOTE_ADDR']}");
-    }
+function admin_check_password(string $pwd): bool {
+    return salt_password($pwd) === scGet('admin_pwd');
+}
 
-    public static function setCookie(): void {
-        global $config;
-        $key = self::getKey();
-        setcookie(self::COOKIE_NAME, $key, time() + self::SESSION_TIMEOUT, '/', $config['cookie_host']);
-    }
+function _admin_get_key(): string {
+    $admin_pwd_hash = scGet('admin_pwd');
+    return salt_password("$admin_pwd_hash|{$_SERVER['REMOTE_ADDR']}");
+}
 
-    public static function unsetCookie(): void {
-        global $config;
-        setcookie(self::COOKIE_NAME, '', 1, '/', $config['cookie_host']);
-    }
+function admin_set_cookie(): void {
+    global $config;
+    $key = _admin_get_key();
+    setcookie(ADMIN_COOKIE_NAME, $key, time() + ADMIN_SESSION_TIMEOUT, '/', $config['cookie_host']);
+}
 
-    public static function logAuth(): void {
-        getDb()->insert('admin_log', [
-            'ts' => time(),
-            'ip' => ip2ulong($_SERVER['REMOTE_ADDR']),
-            'ua' => $_SERVER['HTTP_USER_AGENT'] ?? '',
-        ]);
-    }
+function admin_unset_cookie(): void {
+    global $config;
+    setcookie(ADMIN_COOKIE_NAME, '', 1, '/', $config['cookie_host']);
+}
 
+function admin_log_auth(): void {
+    DB()->insert('admin_log', [
+        'ts' => time(),
+        'ip' => ip2ulong($_SERVER['REMOTE_ADDR']),
+        'ua' => $_SERVER['HTTP_USER_AGENT'] ?? '',
+    ]);
 }
diff --git a/lib/ansi.php b/lib/ansi.php
new file mode 100644
index 0000000..9e0a425
--- /dev/null
+++ b/lib/ansi.php
@@ -0,0 +1,32 @@
+<?php
+
+enum AnsiColor: int {
+    case BLACK   = 0;
+    case RED     = 1;
+    case GREEN   = 2;
+    case YELLOW  = 3;
+    case BLUE    = 4;
+    case MAGENTA = 5;
+    case CYAN    = 6;
+    case WHITE   = 7;
+}
+
+function ansi(string $text,
+              ?AnsiColor $fg = null,
+              ?AnsiColor $bg = null,
+              bool $bold = false,
+              bool $fg_bright = false,
+              bool $bg_bright = false): string {
+    $codes = [];
+    if (!is_null($fg))
+        $codes[] = $fg->value + ($fg_bright ? 90 : 30);
+    if (!is_null($bg))
+        $codes[] = $bg->value + ($bg_bright ? 100 : 40);
+    if ($bold)
+        $codes[] = 1;
+
+    if (empty($codes))
+        return $text;
+
+    return "\033[".implode(';', $codes)."m".$text."\033[0m";
+}
\ No newline at end of file
diff --git a/lib/cli.php b/lib/cli.php
index a860871..910f4c1 100644
--- a/lib/cli.php
+++ b/lib/cli.php
@@ -4,7 +4,7 @@ class cli {
 
     protected ?array $commandsCache = null;
 
-    public function __construct(
+    function __construct(
         protected string $ns
     ) {}
 
@@ -21,7 +21,7 @@ class cli {
         exit(is_null($error) ? 0 : 1);
     }
 
-    public function getCommands(): array {
+    function getCommands(): array {
         if (is_null($this->commandsCache)) {
             $funcs = array_filter(get_defined_functions()['user'], fn(string $f) => str_starts_with($f, $this->ns));
             $funcs = array_map(fn(string $f) => str_replace('_', '-', substr($f, strlen($this->ns.'\\'))), $funcs);
@@ -30,10 +30,10 @@ class cli {
         return $this->commandsCache;
     }
 
-    public function run(): void {
+    function run(): void {
         global $argv, $argc;
 
-        if (PHP_SAPI != 'cli')
+        if (!is_cli())
             cli::die('SAPI != cli');
 
         if ($argc < 2)
diff --git a/lib/config.php b/lib/config.php
deleted file mode 100644
index bb7e5ca..0000000
--- a/lib/config.php
+++ /dev/null
@@ -1,46 +0,0 @@
-<?php
-
-class config {
-
-    public static function get(string $key) {
-        $db = getDb();
-        $q = $db->query("SELECT value FROM config WHERE name=?", $key);
-        if (!$db->numRows($q))
-            return null;
-        return $db->result($q);
-    }
-
-    public static function mget($keys) {
-        $map = [];
-        foreach ($keys as $key) {
-            $map[$key] = null;
-        }
-        
-        $db = getDb();
-        $keys = array_map(fn($s) => $db->escape($s), $keys);
-
-        $q = $db->query("SELECT * FROM config WHERE name IN('".implode("','", $keys)."')");
-        while ($row = $db->fetch($q))
-            $map[$row['name']] = $row['value'];
-
-        return $map;
-    }
-
-    public static function set($key, $value) {
-        $db = getDb();
-        return $db->query("REPLACE INTO config (name, value) VALUES (?, ?)", $key, $value);
-    }
-
-    public static function mset($map) {
-        $rows = [];
-        foreach ($map as $name => $value) {
-            $rows[] = [
-                'name' => $name,
-                'value' => $value
-            ];
-        }
-        $db = getDb();
-        return $db->multipleReplace('config', $rows);
-    }
-
-}
diff --git a/lib/MyParsedown.php b/lib/ext/MyParsedown.php
index 85ed9c4..71dfa7f 100644
--- a/lib/MyParsedown.php
+++ b/lib/ext/MyParsedown.php
@@ -2,8 +2,8 @@
 
 class MyParsedown extends ParsedownExtended {
 
-    public function __construct(
-        ?array $opts = null,
+    function __construct(
+        ?array         $opts = null,
         protected bool $useImagePreviews = false
     ) {
         $parsedown_opts = [
@@ -25,7 +25,7 @@ class MyParsedown extends ParsedownExtended {
     protected function inlineFileAttach($excerpt) {
         if (preg_match('/^{fileAttach:([\w]{8})}{\/fileAttach}/', $excerpt['text'], $matches)) {
             $random_id = $matches[1];
-            $upload = uploads::getByRandomId($random_id);
+            $upload = uploads::getUploadByRandomId($random_id);
             $result = [
                 'extent' => strlen($matches[0]),
                 'element' => [
@@ -73,7 +73,7 @@ class MyParsedown extends ParsedownExtended {
                 }
             }
 
-            $image = uploads::getByRandomId($random_id);
+            $image = uploads::getUploadByRandomId($random_id);
             $result = [
                 'extent' => strlen($matches[0]),
                 'element' => [
@@ -141,7 +141,7 @@ class MyParsedown extends ParsedownExtended {
                 }
             }
 
-            $video = uploads::getByRandomId($random_id);
+            $video = uploads::getUploadByRandomId($random_id);
             $result = [
                 'extent' => strlen($matches[0]),
                 'element' => [
diff --git a/lib/markup.php b/lib/markup.php
index f6ddd0f..9872dae 100644
--- a/lib/markup.php
+++ b/lib/markup.php
@@ -1,5 +1,7 @@
 <?php
 
+require_once 'lib/ext/MyParsedown.php';
+
 class markup {
 
     public static function markdownToHtml(string $md, bool $use_image_previews = true): string {
diff --git a/lib/pages.php b/lib/pages.php
index 281ee52..8524cf3 100644
--- a/lib/pages.php
+++ b/lib/pages.php
@@ -1,9 +1,51 @@
 <?php
 
+class Page extends model {
+
+    const DB_TABLE = 'pages';
+    const DB_KEY = 'short_name';
+
+    public string $title;
+    public string $md;
+    public string $html;
+    public int $ts;
+    public int $updateTs;
+    public bool $visible;
+    public string $shortName;
+
+    function edit(array $fields) {
+        $fields['update_ts'] = time();
+        if ($fields['md'] != $this->md)
+            $fields['html'] = markup::markdownToHtml($fields['md']);
+        parent::edit($fields);
+    }
+
+    function isUpdated(): bool {
+        return $this->updateTs && $this->updateTs != $this->ts;
+    }
+
+    function getHtml(bool $is_retina, string $user_theme): string {
+        $html = $this->html;
+        $html = markup::htmlImagesFix($html, $is_retina, $user_theme);
+        return $html;
+    }
+
+    function getUrl(): string {
+        return "/{$this->shortName}/";
+    }
+
+    function updateHtml(): void {
+        $html = markup::markdownToHtml($this->md);
+        $this->html = $html;
+        DB()->query("UPDATE pages SET html=? WHERE short_name=?", $html, $this->shortName);
+    }
+
+}
+
 class pages {
 
-    public static function add(array $data): ?int {
-        $db = getDb();
+    static function add(array $data): ?int {
+        $db = DB();
         $data['ts'] = time();
         $data['html'] = markup::markdownToHtml($data['md']);
         if (!$db->insert('pages', $data))
@@ -11,12 +53,12 @@ class pages {
         return $db->insertId();
     }
 
-    public static function delete(Page $page): void {
-        getDb()->query("DELETE FROM pages WHERE short_name=?", $page->shortName);
+    static function delete(Page $page): void {
+        DB()->query("DELETE FROM pages WHERE short_name=?", $page->shortName);
     }
 
-    public static function getPageByName(string $short_name): ?Page {
-        $db = getDb();
+    static function getByName(string $short_name): ?Page {
+        $db = DB();
         $q = $db->query("SELECT * FROM pages WHERE short_name=?", $short_name);
         return $db->numRows($q) ? new Page($db->fetch($q)) : null;
     }
@@ -24,8 +66,8 @@ class pages {
     /**
      * @return Page[]
      */
-    public static function getAll(): array {
-        $db = getDb();
+    static function getAll(): array {
+        $db = DB();
         return array_map('Page::create_instance', $db->fetchAll($db->query("SELECT * FROM pages")));
     }
 
diff --git a/lib/posts.php b/lib/posts.php
index 1537749..8ffb92b 100644
--- a/lib/posts.php
+++ b/lib/posts.php
@@ -1,9 +1,202 @@
 <?php
 
+class Post extends model {
+
+    const DB_TABLE = 'posts';
+
+    public int $id;
+    public string $title;
+    public string $md;
+    public string $html;
+    public string $tocHtml;
+    public string $text;
+    public int $ts;
+    public int $updateTs;
+    public bool $visible;
+    public bool $toc;
+    public string $shortName;
+
+    function edit(array $fields) {
+        $cur_ts = time();
+        if (!$this->visible && $fields['visible'])
+            $fields['ts'] = $cur_ts;
+
+        $fields['update_ts'] = $cur_ts;
+
+        if ($fields['md'] != $this->md) {
+            $fields['html'] = markup::markdownToHtml($fields['md']);
+            $fields['text'] = markup::htmlToText($fields['html']);
+        }
+
+        if ((isset($fields['toc']) && $fields['toc']) || $this->toc) {
+            $fields['toc_html'] = markup::toc($fields['md']);
+        }
+
+        parent::edit($fields);
+        $this->updateImagePreviews();
+    }
+
+    function updateHtml() {
+        $html = markup::markdownToHtml($this->md);
+        $this->html = $html;
+
+        DB()->query("UPDATE posts SET html=? WHERE id=?", $html, $this->id);
+    }
+
+    function updateText() {
+        $html = markup::markdownToHtml($this->md);
+        $text = markup::htmlToText($html);
+        $this->text = $text;
+
+        DB()->query("UPDATE posts SET text=? WHERE id=?", $text, $this->id);
+    }
+
+    function getDescriptionPreview(int $len): string {
+        if (mb_strlen($this->text) >= $len)
+            return mb_substr($this->text, 0, $len-3).'...';
+        return $this->text;
+    }
+
+    function getFirstImage(): ?Upload {
+        if (!preg_match('/\{image:([\w]{8})/', $this->md, $match))
+            return null;
+        return uploads::getUploadByRandomId($match[1]);
+    }
+
+    function getUrl(): string {
+        return $this->shortName != '' ? "/{$this->shortName}/" : "/{$this->id}/";
+    }
+
+    function getDate(): string {
+        return date('j M', $this->ts);
+    }
+
+    function getYear(): int {
+        return (int)date('Y', $this->ts);
+    }
+
+    function getFullDate(): string {
+        return date('j F Y', $this->ts);
+    }
+
+    function getUpdateDate(): string {
+        return date('j M', $this->updateTs);
+    }
+
+    function getFullUpdateDate(): string {
+        return date('j F Y', $this->updateTs);
+    }
+
+    function getHtml(bool $is_retina, string $theme): string {
+        $html = $this->html;
+        $html = markup::htmlImagesFix($html, $is_retina, $theme);
+        return $html;
+    }
+
+    function getToc(): ?string {
+        return $this->toc ? $this->tocHtml : null;
+    }
+
+    function isUpdated(): bool {
+        return $this->updateTs && $this->updateTs != $this->ts;
+    }
+
+    /**
+     * @return Tag[]
+     */
+    function getTags(): array {
+        $db = DB();
+        $q = $db->query("SELECT tags.* FROM posts_tags
+            LEFT JOIN tags ON tags.id=posts_tags.tag_id
+            WHERE posts_tags.post_id=?
+            ORDER BY posts_tags.tag_id", $this->id);
+        return array_map('Tag::create_instance', $db->fetchAll($q));
+    }
+
+    /**
+     * @return int[]
+     */
+    function getTagIds(): array {
+        $ids = [];
+        $db = DB();
+        $q = $db->query("SELECT tag_id FROM posts_tags WHERE post_id=? ORDER BY tag_id", $this->id);
+        while ($row = $db->fetch($q)) {
+            $ids[] = (int)$row['tag_id'];
+        }
+        return $ids;
+    }
+
+    function setTagIds(array $new_tag_ids) {
+        $cur_tag_ids = $this->getTagIds();
+        $add_tag_ids = array_diff($new_tag_ids, $cur_tag_ids);
+        $rm_tag_ids = array_diff($cur_tag_ids, $new_tag_ids);
+
+        $db = DB();
+        if (!empty($add_tag_ids)) {
+            $rows = [];
+            foreach ($add_tag_ids as $id)
+                $rows[] = ['post_id' => $this->id, 'tag_id' => $id];
+            $db->multipleInsert('posts_tags', $rows);
+        }
+
+        if (!empty($rm_tag_ids))
+            $db->query("DELETE FROM posts_tags WHERE post_id=? AND tag_id IN(".implode(',', $rm_tag_ids).")", $this->id);
+
+        $upd_tag_ids = array_merge($new_tag_ids, $rm_tag_ids);
+        $upd_tag_ids = array_unique($upd_tag_ids);
+        foreach ($upd_tag_ids as $id)
+            tags::recountTagPosts($id);
+    }
+
+    /**
+     * @param bool $update Whether to overwrite preview if already exists
+     * @return int
+     * @throws Exception
+     */
+    function updateImagePreviews(bool $update = false): int {
+        $images = [];
+        if (!preg_match_all('/\{image:([\w]{8}),(.*?)}/', $this->md, $matches))
+            return 0;
+
+        for ($i = 0; $i < count($matches[0]); $i++) {
+            $id = $matches[1][$i];
+            $w = $h = null;
+            $opts = explode(',', $matches[2][$i]);
+            foreach ($opts as $opt) {
+                if (str_contains($opt, '=')) {
+                    list($k, $v) = explode('=', $opt);
+                    if ($k == 'w')
+                        $w = (int)$v;
+                    else if ($k == 'h')
+                        $h = (int)$v;
+                }
+            }
+            $images[$id][] = [$w, $h];
+        }
+
+        if (empty($images))
+            return 0;
+
+        $images_affected = 0;
+        $uploads = uploads::getUploadsByRandomId(array_keys($images), true);
+        foreach ($uploads as $u) {
+            foreach ($images[$u->randomId] as $s) {
+                list($w, $h) = $s;
+                list($w, $h) = $u->getImagePreviewSize($w, $h);
+                if ($u->createImagePreview($w, $h, $update, $u->imageMayHaveAlphaChannel()))
+                    $images_affected++;
+            }
+        }
+
+        return $images_affected;
+    }
+
+}
+
 class posts {
 
-    public static function getPostsCount(bool $include_hidden = false): int {
-        $db = getDb();
+    static function getCount(bool $include_hidden = false): int {
+        $db = DB();
         $sql = "SELECT COUNT(*) FROM posts";
         if (!$include_hidden) {
             $sql .= " WHERE visible=1";
@@ -11,14 +204,14 @@ class posts {
         return (int)$db->result($db->query($sql));
     }
 
-    public static function getPostsCountByTagId(int $tag_id, bool $include_hidden = false): int {
-        $db = getDb();
+    static function getCountByTagId(int $tag_id, bool $include_hidden = false): int {
+        $db = DB();
         if ($include_hidden) {
             $sql = "SELECT COUNT(*) FROM posts_tags WHERE tag_id=?";
         } else {
             $sql = "SELECT COUNT(*) FROM posts_tags
-                LEFT JOIN posts ON posts.id=posts_tags.post_id
-                WHERE posts_tags.tag_id=? AND posts.visible=1";
+            LEFT JOIN posts ON posts.id=posts_tags.post_id
+            WHERE posts_tags.tag_id=? AND posts.visible=1";
         }
         return (int)$db->result($db->query($sql, $tag_id));
     }
@@ -26,8 +219,8 @@ class posts {
     /**
      * @return Post[]
      */
-    public static function getPosts(int $offset = 0, int $count = -1, bool $include_hidden = false): array {
-        $db = getDb();
+    static function getList(int $offset = 0, int $count = -1, bool $include_hidden = false): array {
+        $db = DB();
         $sql = "SELECT * FROM posts";
         if (!$include_hidden)
             $sql .= " WHERE visible=1";
@@ -41,11 +234,11 @@ class posts {
     /**
      * @return Post[]
      */
-    public static function getPostsByTagId(int $tag_id, bool $include_hidden = false): array {
-        $db = getDb();
+    static function getPostsByTagId(int $tag_id, bool $include_hidden = false): array {
+        $db = DB();
         $sql = "SELECT posts.* FROM posts_tags
-            LEFT JOIN posts ON posts.id=posts_tags.post_id
-            WHERE posts_tags.tag_id=?";
+        LEFT JOIN posts ON posts.id=posts_tags.post_id
+        WHERE posts_tags.tag_id=?";
         if (!$include_hidden)
             $sql .= " AND posts.visible=1";
         $sql .= " ORDER BY posts.ts DESC";
@@ -53,8 +246,8 @@ class posts {
         return array_map('Post::create_instance', $db->fetchAll($q));
     }
 
-    public static function add(array $data = []): int|bool {
-        $db = getDb();
+    static function add(array $data = []): int|bool {
+        $db = DB();
 
         $html = \markup::markdownToHtml($data['md']);
         $text = \markup::htmlToText($html);
@@ -70,64 +263,41 @@ class posts {
 
         $id = $db->insertId();
 
-        $post = posts::get($id);
+        $post = self::get($id);
         $post->updateImagePreviews();
 
         return $id;
     }
 
-    public static function delete(Post $post): void {
+    static function delete(Post $post): void {
         $tags = $post->getTags();
 
-        $db = getDb();
+        $db = DB();
         $db->query("DELETE FROM posts WHERE id=?", $post->id);
         $db->query("DELETE FROM posts_tags WHERE post_id=?", $post->id);
 
         foreach ($tags as $tag)
-            self::recountPostsWithTag($tag->id);
+            tags::recountTagPosts($tag->id);
     }
 
-    public static function getTagIds(array $tags): array {
-        $found_tags = [];
-        $map = [];
-
-        $db = getDb();
-        $q = $db->query("SELECT id, tag FROM tags
-            WHERE tag IN ('".implode("','", array_map(function($tag) use ($db) { return $db->escape($tag); }, $tags))."')");
-        while ($row = $db->fetch($q)) {
-            $found_tags[] = $row['tag'];
-            $map[$row['tag']] = (int)$row['id'];
-        }
-
-        $notfound_tags = array_diff($tags, $found_tags);
-        if (!empty($notfound_tags)) {
-            foreach ($notfound_tags as $tag) {
-                $db->insert('tags', ['tag' => $tag]);
-                $map[$tag] = $db->insertId();
-            }
-        }
-
-        return $map;
-    }
-
-    public static function get(int $id): ?Post {
-        $db = getDb();
+    static function get(int $id): ?Post {
+        $db = DB();
         $q = $db->query("SELECT * FROM posts WHERE id=?", $id);
         return $db->numRows($q) ? new Post($db->fetch($q)) : null;
     }
 
-    public static function getPostByName(string $short_name): ?Post {
-        $db = getDb();
+    static function getByName(string $short_name): ?Post {
+        $db = DB();
         $q = $db->query("SELECT * FROM posts WHERE short_name=?", $short_name);
         return $db->numRows($q) ? new Post($db->fetch($q)) : null;
     }
 
-    public static function getPostsById(array $ids, bool $flat = false): array {
+    static function getPostsById(array $ids, bool $flat = false): array {
         if (empty($ids)) {
             return [];
         }
 
-        $db = getDb();
+        $db = DB();
         $posts = array_fill_keys($ids, null);
 
         $q = $db->query("SELECT * FROM posts WHERE id IN(".implode(',', $ids).")");
@@ -148,44 +318,4 @@ class posts {
         return $posts;
     }
 
-    public static function getAllTags(bool $include_hidden = false): array {
-        $db = getDb();
-        $field = $include_hidden ? 'posts_count' : 'visible_posts_count';
-        $q = $db->query("SELECT * FROM tags WHERE $field > 0 ORDER BY $field DESC, tag");
-        return array_map('Tag::create_instance', $db->fetchAll($q));
-    }
-
-    public static function getTag(string $tag): ?Tag {
-        $db = getDb();
-        $q = $db->query("SELECT * FROM tags WHERE tag=?", $tag);
-        return $db->numRows($q) ? new Tag($db->fetch($q)) : null;
-    }
-
-    /**
-     * @param int $tag_id
-     */
-    public static function recountPostsWithTag($tag_id) {
-        $db = getDb();
-        $count = $db->result($db->query("SELECT COUNT(*) FROM posts_tags WHERE tag_id=?", $tag_id));
-        $vis_count = $db->result($db->query("SELECT COUNT(*) FROM posts_tags
-            LEFT JOIN posts ON posts.id=posts_tags.post_id
-            WHERE posts_tags.tag_id=? AND posts.visible=1", $tag_id));
-        $db->query("UPDATE tags SET posts_count=?, visible_posts_count=? WHERE id=?",
-            $count, $vis_count, $tag_id);
-    }
-
-    public static function splitStringToTags(string $tags): array {
-        $tags = trim($tags);
-        if ($tags == '') {
-            return [];
-        }
-
-        $tags = preg_split('/,\s+/', $tags);
-        $tags = array_filter($tags, function($tag) { return trim($tag) != ''; });
-        $tags = array_map('trim', $tags);
-        $tags = array_map('mb_strtolower', $tags);
-
-        return $tags;
-    }
-
-}
+}
\ No newline at end of file
diff --git a/lib/stored_config.php b/lib/stored_config.php
new file mode 100644
index 0000000..2e7dc8a
--- /dev/null
+++ b/lib/stored_config.php
@@ -0,0 +1,14 @@
+<?php
+
+function scGet(string $key) {
+    $db = DB();
+    $q = $db->query("SELECT value FROM config WHERE name=?", $key);
+    if (!$db->numRows($q))
+        return null;
+    return $db->result($q);
+}
+
+function scSet($key, $value) {
+    $db = DB();
+    return $db->query("REPLACE INTO config (name, value) VALUES (?, ?)", $key, $value);
+}
diff --git a/lib/tags.php b/lib/tags.php
new file mode 100644
index 0000000..ecc9e5a
--- /dev/null
+++ b/lib/tags.php
@@ -0,0 +1,87 @@
+<?php
+
+class Tag extends model implements Stringable {
+
+    const DB_TABLE = 'tags';
+
+    public int $id;
+    public string $tag;
+    public int $postsCount;
+    public int $visiblePostsCount;
+
+    function getUrl(): string {
+        return '/'.$this->tag.'/';
+    }
+
+    function getPostsCount(bool $is_admin): int {
+        return $is_admin ? $this->postsCount : $this->visiblePostsCount;
+    }
+
+    function __toString(): string {
+        return $this->tag;
+    }
+
+}
+
+class tags {
+
+    static function getAll(bool $include_hidden = false): array {
+        $db = DB();
+        $field = $include_hidden ? 'posts_count' : 'visible_posts_count';
+        $q = $db->query("SELECT * FROM tags WHERE $field > 0 ORDER BY $field DESC, tag");
+        return array_map('Tag::create_instance', $db->fetchAll($q));
+    }
+
+    static function get(string $tag): ?Tag {
+        $db = DB();
+        $q = $db->query("SELECT * FROM tags WHERE tag=?", $tag);
+        return $db->numRows($q) ? new Tag($db->fetch($q)) : null;
+    }
+
+    static function recountTagPosts(int $tag_id): void {
+        $db = DB();
+        $count = $db->result($db->query("SELECT COUNT(*) FROM posts_tags WHERE tag_id=?", $tag_id));
+        $vis_count = $db->result($db->query("SELECT COUNT(*) FROM posts_tags
+        LEFT JOIN posts ON posts.id=posts_tags.post_id
+        WHERE posts_tags.tag_id=? AND posts.visible=1", $tag_id));
+        $db->query("UPDATE tags SET posts_count=?, visible_posts_count=? WHERE id=?",
+            $count, $vis_count, $tag_id);
+    }
+
+    static function splitString(string $tags): array {
+        $tags = trim($tags);
+        if ($tags == '')
+            return [];
+        $tags = preg_split('/,\s+/', $tags);
+        $tags = array_filter($tags, static function($tag) { return trim($tag) != ''; });
+        $tags = array_map('trim', $tags);
+        $tags = array_map('mb_strtolower', $tags);
+
+        return $tags;
+    }
+
+    static function getTags(array $tags): array {
+        $found_tags = [];
+        $map = [];
+
+        $db = DB();
+        $q = $db->query("SELECT id, tag FROM tags
+            WHERE tag IN ('".implode("','", array_map(fn($tag) => $db->escape($tag), $tags))."')");
+
+        while ($row = $db->fetch($q)) {
+            $found_tags[] = $row['tag'];
+            $map[$row['tag']] = (int)$row['id'];
+        }
+
+        $notfound_tags = array_diff($tags, $found_tags);
+        if (!empty($notfound_tags)) {
+            foreach ($notfound_tags as $tag) {
+                $db->insert('tags', ['tag' => $tag]);
+                $map[$tag] = $db->insertId();
+            }
+        }
+
+        return $map;
+    }
+
+}
\ No newline at end of file
diff --git a/lib/themes.php b/lib/themes.php
new file mode 100644
index 0000000..f9b9857
--- /dev/null
+++ b/lib/themes.php
@@ -0,0 +1,41 @@
+<?php
+
+const THEMES = [
+    'dark' => [
+        'bg' => 0x222222,
+        // 'alpha' => 0x303132,
+        'alpha' => 0x222222,
+    ],
+    'light' => [
+        'bg' => 0xffffff,
+        // 'alpha' => 0xf2f2f2,
+        'alpha' => 0xffffff,
+    ]
+];
+
+
+function getThemes(): array {
+    return array_keys(THEMES);
+}
+
+function themeExists(string $name): bool {
+    return array_key_exists($name, THEMES);
+}
+
+function getThemeAlphaColorAsRGB(string $name): array {
+    $color = THEMES[$name]['alpha'];
+    $r = ($color >> 16) & 0xff;
+    $g = ($color >> 8) & 0xff;
+    $b = $color & 0xff;
+    return [$r, $g, $b];
+}
+
+function getUserTheme(): string {
+    if (isset($_COOKIE['theme'])) {
+        $val = $_COOKIE['theme'];
+        if (is_array($val))
+            $val = implode($val);
+    } else
+        $val = 'auto';
+    return $val;
+}
diff --git a/lib/uploads.php b/lib/uploads.php
index 6c7e6bc..7540f11 100644
--- a/lib/uploads.php
+++ b/lib/uploads.php
@@ -1,30 +1,30 @@
 <?php
 
-class uploads {
+const UPLOADS_ALLOWED_EXTENSIONS = [
+    'jpg', 'png', 'git', 'mp4', 'mp3', 'ogg', 'diff', 'txt', 'gz', 'tar',
+    'icc', 'icm', 'patch', 'zip', 'brd', 'pdf', 'lua', 'xpi', 'rar', '7z',
+    'tgz', 'bin', 'py', 'pac', 'yaml', 'toml', 'xml', 'json', 'yml',
+];
 
-    protected static $allowedExtensions = [
-        'jpg', 'png', 'git', 'mp4', 'mp3', 'ogg', 'diff', 'txt', 'gz', 'tar',
-        'icc', 'icm', 'patch', 'zip', 'brd', 'pdf', 'lua', 'xpi', 'rar', '7z',
-        'tgz', 'bin', 'py', 'pac', 'yaml', 'toml', 'xml', 'json', 'yml',
-    ];
+class uploads {
 
-    public static function getCount(): int {
-        $db = getDb();
+    static function getCount(): int {
+        $db = DB();
         return (int)$db->result($db->query("SELECT COUNT(*) FROM uploads"));
     }
 
-    public static function isExtensionAllowed(string $ext): bool {
-        return in_array($ext, self::$allowedExtensions);
+    static function isExtensionAllowed(string $ext): bool {
+        return in_array($ext, UPLOADS_ALLOWED_EXTENSIONS);
     }
 
-    public static function add(string $tmp_name, string $name, string $note): ?int {
+    static function add(string $tmp_name, string $name, string $note): ?int {
         global $config;
 
         $name = sanitize_filename($name);
         if (!$name)
             $name = 'file';
 
-        $random_id = self::getNewRandomId();
+        $random_id = self::_getNewUploadRandomId();
         $size = filesize($tmp_name);
         $is_image = detect_image_type($tmp_name) !== false;
         $image_w = 0;
@@ -33,7 +33,7 @@ class uploads {
             list($image_w, $image_h) = getimagesize($tmp_name);
         }
 
-        $db = getDb();
+        $db = DB();
         if (!$db->insert('uploads', [
             'random_id' => $random_id,
             'ts' => time(),
@@ -62,12 +62,12 @@ class uploads {
         return $id;
     }
 
-    public static function delete(int $id): bool {
+    static function delete(int $id): bool {
         $upload = self::get($id);
         if (!$upload)
             return false;
 
-        $db = getDb();
+        $db = DB();
         $db->query("DELETE FROM uploads WHERE id=?", $id);
 
         rrmdir($upload->getDirectory());
@@ -77,14 +77,14 @@ class uploads {
     /**
      * @return Upload[]
      */
-    public static function getAll(): array {
-        $db = getDb();
+    static function getAllUploads(): array {
+        $db = DB();
         $q = $db->query("SELECT * FROM uploads ORDER BY id DESC");
         return array_map('Upload::create_instance', $db->fetchAll($q));
     }
 
-    public static function get(int $id): ?Upload {
-        $db = getDb();
+    static function get(int $id): ?Upload {
+        $db = DB();
         $q = $db->query("SELECT * FROM uploads WHERE id=?", $id);
         if ($db->numRows($q)) {
             return new Upload($db->fetch($q));
@@ -98,12 +98,12 @@ class uploads {
      * @param bool $flat
      * @return Upload[]
      */
-    public static function getUploadsByRandomId(array $ids, bool $flat = false): array {
+    static function getUploadsByRandomId(array $ids, bool $flat = false): array {
         if (empty($ids)) {
             return [];
         }
 
-        $db = getDb();
+        $db = DB();
         $uploads = array_fill_keys($ids, null);
 
         $q = $db->query("SELECT * FROM uploads WHERE random_id IN('".implode('\',\'', array_map([$db, 'escape'], $ids))."')");
@@ -124,8 +124,8 @@ class uploads {
         return $uploads;
     }
 
-    public static function getByRandomId(string $random_id): ?Upload {
-        $db = getDb();
+    static function getUploadByRandomId(string $random_id): ?Upload {
+        $db = DB();
         $q = $db->query("SELECT * FROM uploads WHERE random_id=? LIMIT 1", $random_id);
         if ($db->numRows($q)) {
             return new Upload($db->fetch($q));
@@ -134,12 +134,175 @@ class uploads {
         }
     }
 
-    protected static function getNewRandomId(): string {
-        $db = getDb();
+    static function _getNewUploadRandomId(): string {
+        $db = DB();
         do {
             $random_id = strgen(8);
         } while ($db->numRows($db->query("SELECT id FROM uploads WHERE random_id=?", $random_id)) > 0);
         return $random_id;
-    }
+    }   
 
 }
+
+
+class Upload extends model {
+
+    const DB_TABLE = 'uploads';
+
+    public static array $ImageExtensions = ['jpg', 'jpeg', 'png', 'gif'];
+    public static array $VideoExtensions = ['mp4', 'ogg'];
+
+    public int $id;
+    public string $randomId;
+    public int $ts;
+    public string $name;
+    public int $size;
+    public int $downloads;
+    public int $image; // TODO: remove
+    public int $imageW;
+    public int $imageH;
+    public string $note;
+
+    function getDirectory(): string {
+        global $config;
+        return $config['uploads_dir'].'/'.$this->randomId;
+    }
+
+    function getDirectUrl(): string {
+        global $config;
+        return 'https://'.$config['uploads_host'].'/'.$this->randomId.'/'.$this->name;
+    }
+
+    function getDirectPreviewUrl(int $w, int $h, bool $retina = false): string {
+        global $config;
+        if ($w == $this->imageW && $this->imageH == $h)
+            return $this->getDirectUrl();
+
+        if ($retina) {
+            $w *= 2;
+            $h *= 2;
+        }
+
+        $prefix = $this->imageMayHaveAlphaChannel() ? 'a' : 'p';
+        return 'https://'.$config['uploads_host'].'/'.$this->randomId.'/'.$prefix.$w.'x'.$h.'.jpg';
+    }
+
+    // TODO remove?
+    function incrementDownloads() {
+        $db = DB();
+        $db->query("UPDATE uploads SET downloads=downloads+1 WHERE id=?", $this->id);
+        $this->downloads++;
+    }
+
+    function getSize(): string {
+        return sizeString($this->size);
+    }
+
+    function getMarkdown(): string {
+        if ($this->isImage()) {
+            $md = '{image:'.$this->randomId.',w='.$this->imageW.',h='.$this->imageH.'}{/image}';
+        } else if ($this->isVideo()) {
+            $md = '{video:'.$this->randomId.'}{/video}';
+        } else {
+            $md = '{fileAttach:'.$this->randomId.'}{/fileAttach}';
+        }
+        $md .= ' <!-- '.$this->name.' -->';
+        return $md;
+    }
+
+    function setNote(string $note) {
+        $db = DB();
+        $db->query("UPDATE uploads SET note=? WHERE id=?", $note, $this->id);
+    }
+
+    function isImage(): bool {
+        return in_array(extension($this->name), self::$ImageExtensions);
+    }
+
+    // assume all png images have alpha channel
+    // i know this is wrong, but anyway
+    function imageMayHaveAlphaChannel(): bool {
+        return strtolower(extension($this->name)) == 'png';
+    }
+
+    function isVideo(): bool {
+        return in_array(extension($this->name), self::$VideoExtensions);
+    }
+
+    function getImageRatio(): float {
+        return $this->imageW / $this->imageH;
+    }
+
+    function getImagePreviewSize(?int $w = null, ?int $h = null): array {
+        if (is_null($w) && is_null($h))
+            throw new Exception(__METHOD__.': both width and height can\'t be null');
+
+        if (is_null($h))
+            $h = round($w / $this->getImageRatio());
+
+        if (is_null($w))
+            $w = round($h * $this->getImageRatio());
+
+        return [$w, $h];
+    }
+
+    function createImagePreview(?int $w = null,
+                                       ?int $h = null,
+                                       bool $force_update = false,
+                                       bool $may_have_alpha = false): bool {
+        global $config;
+
+        $orig = $config['uploads_dir'].'/'.$this->randomId.'/'.$this->name;
+        $updated = false;
+
+        foreach (themes::getThemes() as $theme) {
+            if (!$may_have_alpha && $theme == 'dark')
+                continue;
+
+            for ($mult = 1; $mult <= 2; $mult++) {
+                $dw = $w * $mult;
+                $dh = $h * $mult;
+
+                $prefix = $may_have_alpha ? 'a' : 'p';
+                $dst = $config['uploads_dir'].'/'.$this->randomId.'/'.$prefix.$dw.'x'.$dh.($theme == 'dark' ? '_dark' : '').'.jpg';
+
+                if (file_exists($dst)) {
+                    if (!$force_update)
+                        continue;
+                    unlink($dst);
+                }
+
+                $img = imageopen($orig);
+                imageresize($img, $dw, $dh, themes::getThemeAlphaColorAsRGB($theme));
+                imagejpeg($img, $dst, $mult == 1 ? 93 : 67);
+                imagedestroy($img);
+
+                setperm($dst);
+                $updated = true;
+            }
+        }
+
+        return $updated;
+    }
+
+    /**
+     * @return int  Number of deleted files
+     */
+    function deleteAllImagePreviews(): int {
+        global $config;
+        $dir = $config['uploads_dir'].'/'.$this->randomId;
+        $files = scandir($dir);
+        $deleted = 0;
+        foreach ($files as $f) {
+            if (preg_match('/^[ap](\d+)x(\d+)(?:_dark)?\.jpg$/', $f)) {
+                if (is_file($dir.'/'.$f))
+                    unlink($dir.'/'.$f);
+                else
+                    logError(__METHOD__.': '.$dir.'/'.$f.' is not a file!');
+                $deleted++;
+            }
+        }
+        return $deleted;
+    }
+
+}
\ No newline at end of file