Add spoiler tags

Boards can have spoiler processors enabled on them now.

Signed-off-by: Alek Ratzloff <alekratz@gmail.com>

board/migrations/0004_board_spoilers.py

@@ -0,0 +1,18 @@
+# Generated by Django 4.1b1 on 2022-07-20 07:57
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("board", "0003_board_hidden"),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name="board",
+            name="spoilers",
+            field=models.BooleanField(default=False),
+        ),
+    ]

board/models.py

@@ -65,6 +65,8 @@ class Board(models.Model):
     readonly = models.BooleanField(default=False)
     # Whether this board appears in the board listing or not
     hidden = models.BooleanField(default=False)
+    # Whether to allow users to use spoiler tags on this board
+    spoilers = models.BooleanField(default=False)
 
     @property
     def threads(self):

board/static/board/style.css

@@ -169,6 +169,17 @@ th {
     right: 0px;
 }
 
+/* Spoilers */
+
+.spoiler {
+    color: #000;
+    background-color: #000;
+}
+
+.spoiler:hover {
+    background-color: rgb(0, 0, 0, 0);
+}
+
 /* News */
 .news_header {
     font-size: small;

board/templatetags/post_body.py

@@ -19,8 +19,9 @@ def htmlspecialchars(t: str):
 
 
 class ReplyBuilder:
-    def __init__(self, text: str):
+    def __init__(self, text: str, parse_spoilers: bool = False):
         self.text = text
+        self.parse_spoilers = parse_spoilers
         self.index = 0
         self.final = ""
 
@@ -51,6 +52,8 @@ class ReplyBuilder:
                 self.do_reply()
             elif self.remain[:4] == ">":
                 self.do_quote()
+            elif self.parse_spoilers and self.remain[:9] == "[spoiler]":
+                self.do_spoiler()
             else:
                 self.final += self.c
                 self.adv()
@@ -81,12 +84,22 @@ class ReplyBuilder:
         else:
             self.final += f'<span class="post_link_broken">&gt;&gt;{post_id}</span>'
 
+    def do_spoiler(self):
+        self.adv(9)
+        spoiled = ""
+        while self.c and self.remain[:10] != "[/spoiler]":
+            spoiled += self.c
+            self.adv()
+        if self.remain[:10] == "[/spoiler]":
+            self.adv(10)
+        self.final += f'<span class="spoiler">{spoiled}</span>'
+
 
 @register.filter(name="post_body")
 def post_body(post: Post) -> str:
     text = htmlspecialchars(post.text)
 
-    text = ReplyBuilder(text).build()
+    text = ReplyBuilder(text, parse_spoilers=post.board.spoilers).build()
 
     # Finally, replace linebreaks
     text = text.replace("\n", "<br/>")