From 5a6929e20bcc522893b60dada0f2db28c0699567 Mon Sep 17 00:00:00 2001
From: nekobit <nekobit@noemail.net>
Date: Mon, 6 Jun 2022 23:49:44 +0000
Subject: [PATCH] Regex fix mentions

FossilOrigin-Name: a625188e6d0161d3377da2abcaebd23756626b7a1a404cec46d20ea467d6d820
---
 docs/INSTALL.md | 10 +++-----
 src/status.c    | 67 +++++++++++++++++++++++++++++++++++++++++--------
 src/status.h    |  1 +
 3 files changed, 61 insertions(+), 17 deletions(-)

diff --git a/docs/INSTALL.md b/docs/INSTALL.md
index 6e2f162..7d79e24 100644
--- a/docs/INSTALL.md
+++ b/docs/INSTALL.md
@@ -8,13 +8,9 @@ For the following GNU/Linux distributions, you will need the following libraries
   - Debian: `libcurl4-gnutls-dev`
   - Arch: `curl`
   - Void: `libcurl libcurl-devel`
-- libcjson
-  - Debian: `libcjson-dev`
-  - Arch: `cjson`
-  - Void: `cJSON cJSON-devel`
-- libpcre
-  - Debian: `libpcre3-dev`
-  - Void: `libpcre2`
+- libpcre2
+  - Debian: `libpcre2-dev`
+  - Void: `pcre2 pcre2-devel`
 - libfcgi
   - Debian: `libfcgi-dev`
   - Void: `fcgi fcgi-devel`
diff --git a/src/status.c b/src/status.c
index 6fef7da..154ba35 100644
--- a/src/status.c
+++ b/src/status.c
@@ -394,20 +394,67 @@ char* reformat_status(struct session* ssn,
                       size_t emos_len)
 {
     if (!content) return NULL;
-    char* gt_res = NULL;
-    char* emo_res;
-    if (ssn->config.stat_greentexts)
-        gt_res = greentextify(content);
-    else
-        gt_res = content;
+    char* res = make_mentions_local(content);
+    char* gt_res, *emo_res;
     
     if (emos)
     {
-        emo_res = emojify(gt_res, emos, emos_len);
-        if (gt_res != content) free(gt_res);
-        return emo_res;
+        emo_res = emojify(res, emos, emos_len);
+        if (emo_res != content && res != content)
+            free(res);
+        res = emo_res;
     }
-    return gt_res;
+    
+    if (ssn->config.stat_greentexts)
+    {
+        gt_res = greentextify(res);
+        if (gt_res != res && res != content)
+            free(res);
+        res = gt_res;
+    }
+    
+    return res;
+}
+
+#define REGEX_MENTION "<a .*?href=\"https?:\\/\\/(.*?)\\/(?:@|users/)?(.*?)?\".*?>"
+
+char* make_mentions_local(char* content)
+{
+    char* url_format;
+    int error;
+    PCRE2_SIZE erroffset;
+    size_t res_len = 512;
+    char* res = malloc(res_len);
+    pcre2_code* re = pcre2_compile((PCRE2_SPTR)REGEX_MENTION,
+                                   PCRE2_ZERO_TERMINATED, 0,
+                                   &error, &erroffset, NULL);
+    if (re == NULL)
+    {
+        fprintf(stderr, "Couldn't parse regex at offset %ld: %d\n", erroffset, error);
+        pcre2_code_free(re);
+        return NULL;
+    }
+
+    int len = easprintf(&url_format,
+                        "<a class=\"mention\" href=\"http%s://%s/@$2@$1\">",
+                        config_host_url_insecure ? "" : "s",
+                        getenv("HTTP_HOST"));
+
+    int amt = pcre2_substitute(re,
+                               (PCRE2_SPTR)content,
+                               PCRE2_ZERO_TERMINATED,
+                               0,
+                               PCRE2_SUBSTITUTE_EXTENDED | PCRE2_SUBSTITUTE_GLOBAL,
+                               NULL,
+                               NULL,
+                               (PCRE2_SPTR)url_format,
+                               len,
+                               (PCRE2_UCHAR*)res,
+                               &res_len);
+    
+
+    free(url_format);
+    return amt ? res : content;
 }
 
 char* greentextify(char* content)
diff --git a/src/status.h b/src/status.h
index e2dce11..adc2485 100644
--- a/src/status.h
+++ b/src/status.h
@@ -92,6 +92,7 @@ char* reformat_status(struct session* ssn,
                       struct mstdnt_emoji* emos,
                       size_t emos_len);
 char* greentextify(char* content);
+char* make_mentions_local(char* content);
 
 // Status frontends
 void status_view(struct session* ssn, mastodont_t* api, char** data);