support dark mode for images with alpha channel

3 files changed, 45 insertions, 37 deletions

diff --git a/model/Page.php b/model/Page.php
index 6711a2c..f516836 100644
--- a/model/Page.php
+++ b/model/Page.php
@@ -24,10 +24,9 @@ class Page extends Model {
         return $this->updateTs && $this->updateTs != $this->ts;
     }
 
-    public function getHtml(bool $retina): string {
+    public function getHtml(bool $is_retina, string $user_theme): string {
         $html = $this->html;
-        if ($retina)
-            $html = markup::htmlRetinaFix($html);
+        $html = markup::htmlImagesFix($html, $is_retina, $user_theme);
         return $html;
     }
 
diff --git a/model/Post.php b/model/Post.php
index 10a396b..b0360ac 100644
--- a/model/Post.php
+++ b/model/Post.php
@@ -22,8 +22,8 @@ class Post extends Model {
         $data['update_ts'] = $cur_ts;
 
         if ($data['md'] != $this->md) {
-            $data['html'] = \markup::markdownToHtml($data['md']);
-            $data['text'] = \markup::htmlToText($data['html']);
+            $data['html'] = markup::markdownToHtml($data['md']);
+            $data['text'] = markup::htmlToText($data['html']);
         }
 
         parent::edit($data);
@@ -31,15 +31,15 @@ class Post extends Model {
     }
 
     public function updateHtml() {
-        $html = \markup::markdownToHtml($this->md);
+        $html = markup::markdownToHtml($this->md);
         $this->html = $html;
 
         getDb()->query("UPDATE posts SET html=? WHERE id=?", $html, $this->id);
     }
 
     public function updateText() {
-        $html = \markup::markdownToHtml($this->md);
-        $text = \markup::htmlToText($html);
+        $html = markup::markdownToHtml($this->md);
+        $text = markup::htmlToText($html);
         $this->text = $text;
 
         getDb()->query("UPDATE posts SET text=? WHERE id=?", $text, $this->id);
@@ -81,10 +81,9 @@ class Post extends Model {
         return date('j F Y', $this->updateTs);
     }
 
-    public function getHtml(bool $retina): string {
+    public function getHtml(bool $is_retina, string $theme): string {
         $html = $this->html;
-        if ($retina)
-            $html = markup::htmlRetinaFix($html);
+        $html = markup::htmlImagesFix($html, $is_retina, $theme);
         return $html;
     }
 
@@ -173,9 +172,8 @@ class Post extends Model {
             foreach ($images[$u->randomId] as $s) {
                 list($w, $h) = $s;
                 list($w, $h) = $u->getImagePreviewSize($w, $h);
-                if ($u->createImagePreview($w, $h, $update)) {
+                if ($u->createImagePreview($w, $h, $update, $u->imageMayHaveAlphaChannel()))
                     $images_affected++;
-                }
             }
         }
 
diff --git a/model/Upload.php b/model/Upload.php
index 441a14d..06b348b 100644
--- a/model/Upload.php
+++ b/model/Upload.php
@@ -38,7 +38,8 @@ class Upload extends Model {
             $h *= 2;
         }
 
-        return 'https://'.$config['uploads_host'].'/'.$this->randomId.'/p'.$w.'x'.$h.'.jpg';
+        $prefix = $this->imageMayHaveAlphaChannel() ? 'a' : 'p';
+        return 'https://'.$config['uploads_host'].'/'.$this->randomId.'/'.$prefix.$w.'x'.$h.'.jpg';
     }
 
     // TODO remove?
@@ -73,6 +74,12 @@ class Upload extends Model {
         return in_array(extension($this->name), self::$ImageExtensions);
     }
 
+    // assume all png images have alpha channel
+    // i know this is wrong, but anyway
+    public function imageMayHaveAlphaChannel(): bool {
+        return strtolower(extension($this->name)) == 'png';
+    }
+
     public function isVideo(): bool {
         return in_array(extension($this->name), self::$VideoExtensions);
     }
@@ -94,36 +101,40 @@ class Upload extends Model {
         return [$w, $h];
     }
 
-    /**
-     * @param ?int $w
-     * @param ?int $h
-     * @param bool $update Whether to proceed if preview already exists
-     * @return bool
-     */
-    public function createImagePreview(?int $w = null, ?int $h = null, bool $update = false): bool {
+    public 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;
 
-        for ($mult = 1; $mult <= 2; $mult++) {
-            $dw = $w * $mult;
-            $dh = $h * $mult;
-            $dst = $config['uploads_dir'].'/'.$this->randomId.'/p'.$dw.'x'.$dh.'.jpg';
+        foreach (themes::getThemes() as $theme) {
+            if (!$may_have_alpha && $theme == 'dark')
+                continue;
 
-            if (file_exists($dst)) {
-                if (!$update)
-                    continue;
-                unlink($dst);
-            }
+            for ($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';
 
-            $img = imageopen($orig);
-            imageresize($img, $dw, $dh, [255, 255, 255]);
-            imagejpeg($img, $dst, $mult == 1 ? 93 : 67);
-            imagedestroy($img);
+                if (file_exists($dst)) {
+                    if (!$force_update)
+                        continue;
+                    unlink($dst);
+                }
 
-            setperm($dst);
-            $updated = true;
+                $img = imageopen($orig);
+                imageresize($img, $dw, $dh, themes::getThemeAlphaColorAsRGB($theme));
+                imagejpeg($img, $dst, $mult == 1 ? 93 : 67);
+                imagedestroy($img);
+
+                setperm($dst);
+                $updated = true;
+            }
         }
 
         return $updated;
@@ -138,7 +149,7 @@ class Upload extends Model {
         $files = scandir($dir);
         $deleted = 0;
         foreach ($files as $f) {
-            if (preg_match('/^p(\d+)x(\d+)\.jpg$/', $f)) {
+            if (preg_match('/^[ap](\d+)x(\d+)(?:_dark)?\.jpg$/', $f)) {
                 if (is_file($dir.'/'.$f))
                     unlink($dir.'/'.$f);
                 else