fix: Wikipedia article links use _ for spaces (0.43.2)

CHANGELOG.md

@@ -1,3 +1,7 @@
+2026.07.26 - Fix Wikipedia article links using wrong space encoding. (0.43.2)
+
+- Fixed Wikipedia article links in `!wp` responses using `+` instead of `_` for spaces (e.g. `CLever+Audio+Plug-in` → `CLever_Audio_Plug-in`). The `wp_url_encode()` function was used for both API query parameters (where `+` is correct) and article title URLs (where Wikipedia expects `_`). Added `wp_url_encode_title()` that encodes spaces as underscores for use in article link construction, and switched all article link encodings to use it.
+
 2026.07.26 - Improved Wikipedia results formatting and article extracts. (0.43.1)
 
 - Changed multi-result mode from a single pipe-separated message to individual messages: each result is now sent as its own IRC message (`Title — snippet`) followed by a separate "Read full article: LINK" message. This makes results easier to read in busy channels and ensures each article link is immediately visible.

CMakeLists.txt

@@ -1,6 +1,6 @@
 cmake_minimum_required(VERSION 3.13)
 
-project(zynk VERSION 0.43.1 LANGUAGES C)
+project(zynk VERSION 0.43.2 LANGUAGES C)
 
 # Prefer C99; the code is compatible with C99/C11
 set(CMAKE_C_STANDARD 99)

cmd_wp.h

@@ -73,6 +73,39 @@ static void wp_url_encode(const char *src, char *dst, size_t dstsz) {
   dst[di] = '\0';
 }
 
+/*
+ * wp_url_encode_title - Percent-encode a Wikipedia article title for use in a URL path.
+ *
+ * Like wp_url_encode() but encodes spaces as underscores instead of plus signs,
+ * matching Wikipedia's URL convention for article titles (e.g. "CLever Audio
+ * Plug-in" becomes "CLever_Audio_Plug-in" instead of "CLever+Audio+Plug-in").
+ *
+ * Parameters:
+ *   src   - The article title to encode.
+ *   dst   - Output buffer for the encoded string.
+ *   dstsz - Size of the output buffer.
+ *
+ * Returns: void (output is written to dst, NUL-terminated).
+ */
+static void wp_url_encode_title(const char *src, char *dst, size_t dstsz) {
+  static const char hex[] = "0123456789ABCDEF";
+  size_t di = 0;
+  for (; *src && di + 4 < dstsz; src++) {
+    unsigned char c = (unsigned char)*src;
+    if (isalnum(c) || c == '-' || c == '_' || c == '.' || c == '~') {
+      dst[di++] = c;
+    } else if (c == ' ') {
+      dst[di++] = '_';
+    } else {
+      if (di + 3 >= dstsz) break;
+      dst[di++] = '%';
+      dst[di++] = hex[c >> 4];
+      dst[di++] = hex[c & 0x0F];
+    }
+  }
+  dst[di] = '\0';
+}
+
 /*
  * wp_decode_json_string - Decode JSON string escape sequences in-place.
  *
@@ -310,7 +343,7 @@ int cmd_wp(Session *s, const char *msg, const char *reply_target, const char *sr
       return 1;
     }
     char enc_title[512];
-    wp_url_encode(title, enc_title, sizeof enc_title);
+    wp_url_encode_title(title, enc_title, sizeof enc_title);
     char extract_url[1024];
     snprintf(extract_url, sizeof extract_url,
       "https://en.wikipedia.org/w/api.php?action=query&titles=%s&prop=extracts&explaintext=true&exchars=800&format=json",
@@ -361,7 +394,7 @@ int cmd_wp(Session *s, const char *msg, const char *reply_target, const char *sr
       wp_collapse_spaces(snippet_raw);
       if (!title[0]) continue;
       char enc_title[512];
-      wp_url_encode(title, enc_title, sizeof enc_title);
+      wp_url_encode_title(title, enc_title, sizeof enc_title);
       char line[1024];
       if (snippet_raw[0]) {
         char snippet_short[256];