Recognise URLs in plain text message bodies (#476)

Cargo.lock

@@ -2274,6 +2274,7 @@ dependencies = [
  "image",
  "lazy_static 1.5.0",
  "libc",
+ "linkify",
  "markup5ever_rcdom",
  "matrix-sdk",
  "mime",
@@ -2831,6 +2832,15 @@ dependencies = [
  "vcpkg",
 ]
 
+[[package]]
+name = "linkify"
+version = "0.10.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f1dfa36d52c581e9ec783a7ce2a5e0143da6237be5811a0b3153fedfdbe9f780"
+dependencies = [
+ "memchr",
+]
+
 [[package]]
 name = "linux-raw-sys"
 version = "0.3.8"

Cargo.toml

@@ -64,6 +64,7 @@ unicode-width = "0.1.10"
 url = {version = "^2.2.2", features = ["serde"]}
 edit = "0.1.4"
 humansize = "2.0.0"
+linkify = "0.10.0"
 
 [dependencies.comrak]
 version = "0.22.0"

src/message/html.rs

@@ -524,11 +524,11 @@ impl StyleTree {
 }
 
 pub struct TreeGenState {
-    link_num: u8,
+    pub link_num: u8,
 }
 
 impl TreeGenState {
-    fn next_link_char(&mut self) -> Option<char> {
+    pub fn next_link_char(&mut self) -> Option<char> {
         let num = self.link_num;
 
         if num < 62 {

src/message/mod.rs

@@ -72,6 +72,7 @@ mod state;
 
 pub use self::compose::text_to_message;
 use self::state::{body_cow_state, html_state};
+pub use html::TreeGenState;
 
 type ProtocolPreview<'a> = (&'a Protocol, u16, u16);
 

src/windows/room/chat.rs

@@ -86,7 +86,14 @@ use crate::base::{
     SendAction,
 };
 
-use crate::message::{text_to_message, Message, MessageEvent, MessageKey, MessageTimeStamp};
+use crate::message::{
+    text_to_message,
+    Message,
+    MessageEvent,
+    MessageKey,
+    MessageTimeStamp,
+    TreeGenState,
+};
 use crate::worker::Requester;
 
 use super::scrollback::{Scrollback, ScrollbackState};
@@ -226,10 +233,14 @@ impl ChatState {
 
                             let links = if let Some(html) = &msg.html {
                                 html.get_links()
-                            } else if let Ok(url) = Url::parse(&msg.event.body()) {
-                                vec![('0', url)]
                             } else {
-                                vec![]
+                                linkify::LinkFinder::new()
+                                    .links(&msg.event.body())
+                                    .filter_map(|u| Url::parse(u.as_str()).ok())
+                                    .scan(TreeGenState { link_num: 0 }, |state, u| {
+                                        state.next_link_char().map(|c| (c, u))
+                                    })
+                                    .collect()
                             };
 
                             if links.is_empty() {