From 5605eb90405f732019043990cd39f1fd96e72182 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Daniel=20Ekl=C3=B6f?= <daniel@ekloef.se>
Date: Sat, 22 May 2021 16:42:43 +0200
Subject: [PATCH 1/2] url-mode: remove overlapping URLs, not just duplicates

  echo -e '\e]8;;https://www.foo.bar\e\\https://www.foo\e]8;;\e\\.bar'

will produce an OSC-8 URL (https://www.foo) that is slightly shorter
than the auto-detected one (https://www.foo.bar).

This produces strange results in URL mode. For example, if
url.osc8-underline=always, the OSC8 underline will be removed when
url-mode is exited.

This patch changes the behavior so that auto-detected URLs that
overlap OSC-8 URLs are removed.

Note that OSC-8 URLs cannot overlap with each other, and that
auto-detected URLs also cannot overlap with each other.
---
 CHANGELOG.md |  1 +
 terminal.h   |  1 +
 url-mode.c   | 46 ++++++++++++++++++++++++++++++++++++----------
 3 files changed, 38 insertions(+), 10 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 0474fe3d..e5e4bbf4 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -82,6 +82,7 @@
   (https://codeberg.org/dnkl/foot/issues/478).
 * `ctrl + w` (_extend-to-word-boundary_) can now be used across lines
   (https://codeberg.org/dnkl/foot/issues/421).
+* Ignore auto-detected URLs that overlap with OSC-8 URLs.
 
 
 ### Deprecated
diff --git a/terminal.h b/terminal.h
index 472b4938..1721a4c1 100644
--- a/terminal.h
+++ b/terminal.h
@@ -258,6 +258,7 @@ struct url {
     struct coord end;
     enum url_action action;
     bool url_mode_dont_change_url_attr; /* Entering/exiting URL mode doesn’t touch the cells’ attr.url */
+    bool osc8;
 };
 typedef tll(struct url) url_list_t;
 
diff --git a/url-mode.c b/url-mode.c
index dc63ebbe..e036b1f2 100644
--- a/url-mode.c
+++ b/url-mode.c
@@ -370,7 +370,8 @@ auto_detected(const struct terminal *term, enum url_action action,
                                 .url = url_utf8,
                                 .start = start,
                                 .end = end,
-                                .action = action}));
+                                .action = action,
+                                .osc8 = false}));
                     }
 
                     state = STATE_PROTOCOL;
@@ -424,26 +425,51 @@ osc8_uris(const struct terminal *term, enum url_action action, url_list_t *urls)
                    .start = start,
                    .end = end,
                    .action = action,
-                   .url_mode_dont_change_url_attr = dont_touch_url_attr}));
+                   .url_mode_dont_change_url_attr = dont_touch_url_attr,
+                   .osc8 = true}));
        }
     }
 }
 
 static void
-remove_duplicates(url_list_t *urls)
+remove_overlapping(url_list_t *urls, int cols)
 {
     tll_foreach(*urls, outer) {
         tll_foreach(*urls, inner) {
             if (outer == inner)
                 continue;
 
-            if (outer->item.start.row == inner->item.start.row &&
-                outer->item.start.col == inner->item.start.col &&
-                outer->item.end.row == inner->item.end.row &&
-                outer->item.end.col == inner->item.end.col)
+            const struct url *out = &outer->item;
+            const struct url *in = &inner->item;
+
+            uint64_t in_start = in->start.row * cols + in->start.col;
+            uint64_t in_end = in->end.row * cols + in->end.col;
+
+            uint64_t out_start = out->start.row * cols + out->start.col;
+            uint64_t out_end = out->end.row * cols + out->end.col;
+
+            if ((in_start <= out_start && in_end >= out_start) ||
+                (in_start <= out_end && in_end >= out_end) ||
+                (in_start >= out_start && in_end <= out_end))
             {
-                url_destroy(&inner->item);
-                tll_remove(*urls, inner);
+                /*
+                 * OSC-8 URLs can’t overlap with each
+                 * other.
+                 *
+                 * Similarily, auto-detected URLs cannot overlap with
+                 * each other.
+                 *
+                 * But OSC-8 URLs can overlap with auto-detected ones.
+                 */
+                xassert(in->osc8 || out->osc8);
+
+                if (in->osc8) {
+                    url_destroy(&outer->item);
+                    tll_remove(*urls, outer);
+                } else {
+                    url_destroy(&inner->item);
+                    tll_remove(*urls, inner);
+                }
             }
         }
     }
@@ -455,7 +481,7 @@ urls_collect(const struct terminal *term, enum url_action action, url_list_t *ur
     xassert(tll_length(term->urls) == 0);
     osc8_uris(term, action, urls);
     auto_detected(term, action, urls);
-    remove_duplicates(urls);
+    remove_overlapping(urls, term->grid->num_cols);
 }
 
 static int

From a9e8ba09322d563e2de6fb48993727b509442c83 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Daniel=20Ekl=C3=B6f?= <daniel@ekloef.se>
Date: Sat, 22 May 2021 17:08:14 +0200
Subject: [PATCH 2/2] url-mode: codespell

---
 url-mode.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/url-mode.c b/url-mode.c
index e036b1f2..9473dc14 100644
--- a/url-mode.c
+++ b/url-mode.c
@@ -456,7 +456,7 @@ remove_overlapping(url_list_t *urls, int cols)
                  * OSC-8 URLs can’t overlap with each
                  * other.
                  *
-                 * Similarily, auto-detected URLs cannot overlap with
+                 * Similarly, auto-detected URLs cannot overlap with
                  * each other.
                  *
                  * But OSC-8 URLs can overlap with auto-detected ones.