From 2c00c7b0b585867495a505a9daf3ab48aa1dfa0b Mon Sep 17 00:00:00 2001
From: default <nobody@localhost>
Date: Sat, 1 Oct 2022 09:12:33 +0200
Subject: [PATCH] New web action 'Unfollow'.

---
 activitypub.c | 11 +++++++++++
 data.c        | 21 +++++++++++++++++++++
 html.c        | 16 +++++++++++++++-
 snac.h        |  2 ++
 4 files changed, 49 insertions(+), 1 deletion(-)

diff --git a/activitypub.c b/activitypub.c
index 5e26fb6..29ce676 100644
--- a/activitypub.c
+++ b/activitypub.c
@@ -437,6 +437,17 @@ d_char *msg_create(snac *snac, char *object)
 }
 
 
+d_char *msg_undo(snac *snac, char *object)
+/* creates an 'Undo' message */
+{
+    d_char *msg = msg_base(snac, "Undo", "@object", snac->actor, "@now", object);
+
+    msg = xs_dict_append(msg, "to", xs_dict_get(object, "object"));
+
+    return msg;
+}
+
+
 d_char *msg_follow(snac *snac, char *actor)
 /* creates a 'Follow' message */
 {
diff --git a/data.c b/data.c
index 9051810..4ff5a84 100644
--- a/data.c
+++ b/data.c
@@ -693,6 +693,27 @@ int following_check(snac *snac, char *actor)
 }
 
 
+int following_get(snac *snac, char *actor, d_char **data)
+/* returns the 'Follow' object */
+{
+    xs *fn = _following_fn(snac, actor);
+    FILE *f;
+    int status = 200;
+
+    if ((f = fopen(fn, "r")) != NULL) {
+        xs *j = xs_readall(f);
+
+        fclose(f);
+
+        *data = xs_json_loads(j);
+    }
+    else
+        status = 404;
+
+    return status;
+}
+
+
 d_char *_muted_fn(snac *snac, char *actor)
 {
     xs *md5 = xs_md5_hex(actor, strlen(actor));
diff --git a/html.c b/html.c
index 4e60903..45e1963 100644
--- a/html.c
+++ b/html.c
@@ -867,7 +867,7 @@ int html_post_handler(d_char *req, char *q_path, d_char *payload, int p_size,
         }
         else
         if (strcmp(action, L("Follow")) == 0) {
-            char *msg = msg_follow(&snac, actor);
+            xs *msg = msg_follow(&snac, actor);
 
             /* reload the actor from the message, in may be different */
             actor = xs_dict_get(msg, "object");
@@ -878,6 +878,20 @@ int html_post_handler(d_char *req, char *q_path, d_char *payload, int p_size,
         }
         else
         if (strcmp(action, L("Unfollow")) == 0) {
+            /* get the following object */
+            xs *object = NULL;
+
+            if (valid_status(following_get(&snac, actor, &object))) {
+                xs *msg = msg_undo(&snac, xs_dict_get(object, "object"));
+
+                following_del(&snac, actor);
+
+                enqueue_output(&snac, msg, actor, 0);
+
+                snac_log(&snac, xs_fmt("unfollowed actor %s", actor));
+            }
+            else
+                snac_log(&snac, xs_fmt("actor is not being followed %s", actor));
         }
         else
         if (strcmp(action, L("Delete")) == 0) {
diff --git a/snac.h b/snac.h
index 26f153e..afccc65 100644
--- a/snac.h
+++ b/snac.h
@@ -75,6 +75,7 @@ d_char *local_list(snac *snac, int max);
 int following_add(snac *snac, char *actor, char *msg);
 int following_del(snac *snac, char *actor);
 int following_check(snac *snac, char *actor);
+int following_get(snac *snac, char *actor, d_char **data);
 
 void mute(snac *snac, char *actor);
 void unmute(snac *snac, char *actor);
@@ -112,6 +113,7 @@ d_char *msg_admiration(snac *snac, char *object, char *type);
 d_char *msg_create(snac *snac, char *object);
 d_char *msg_follow(snac *snac, char *actor);
 d_char *msg_note(snac *snac, char *content, char *rcpts, char *in_reply_to);
+d_char *msg_undo(snac *snac, char *object);
 
 int activitypub_request(snac *snac, char *url, d_char **data);
 int actor_request(snac *snac, char *actor, d_char **data);