From 35ae18e5c351739b2d80acd0d77db7856caf2596 Mon Sep 17 00:00:00 2001
From: Coral Pink <coral.pink@disr.it>
Date: Fri, 26 Dec 2025 00:11:31 +0100
Subject: [PATCH] highlight & loop through urls in both directions

Based on a previous patch (st-copyurl-20230406-211964d.diff).
This patch fixes two bugs when looping forward:
1. URLs on the same line iterated the same way as when looping backward
   (right-to-left). Now it's left-to-right.
2. When an URL in the first row was selected, looping forward didn't
   work, it just got stuck there.

Co-authored-by: Gildasio Junior <gildasiojunior@riseup.net>
---
 config.def.h |   2 +
 st.c         | 127 +++++++++++++++++++++++++++++++++++++++++++++++++++
 st.h         |   1 +
 3 files changed, 130 insertions(+)

diff --git a/config.def.h b/config.def.h
index 2cd740a..f2d8d77 100644
--- a/config.def.h
+++ b/config.def.h
@@ -201,6 +201,8 @@ static Shortcut shortcuts[] = {
 	{ TERMMOD,              XK_Y,           selpaste,       {.i =  0} },
 	{ ShiftMask,            XK_Insert,      selpaste,       {.i =  0} },
 	{ TERMMOD,              XK_Num_Lock,    numlock,        {.i =  0} },
+	{ MODKEY,               XK_l,           copyurl,        {.i =  0} },
+	{ MODKEY|ShiftMask,     XK_L,           copyurl,        {.i =  1} }
 };
 
 /*
diff --git a/st.c b/st.c
index 8e57991..10dd9d5 100644
--- a/st.c
+++ b/st.c
@@ -201,6 +201,8 @@ static void tdefutf8(char);
 static int32_t tdefcolor(const int *, int *, int);
 static void tdeftran(char);
 static void tstrsequence(uchar);
+static const char *findlastany(const char *, const char**, size_t);
+static const char *findfirstany(const char *, const char**, size_t);
 
 static void drawregion(int, int, int, int);
 
@@ -2699,3 +2701,128 @@ redraw(void)
 	tfulldirt();
 	draw();
 }
+
+const char *
+findlastany(const char *str, const char**find, size_t len)
+{
+	const char *found = NULL;
+	int i = 0;
+
+	for (found = str + strlen(str) - 1; found >= str; --found) {
+		for(i = 0; i < len; i++) {
+			if (strncmp(found, find[i], strlen(find[i])) == 0) {
+				return found;
+			}
+		}
+	}
+
+	return NULL;
+}
+
+const char *
+findfirstany(const char *str, const char**find, size_t len)
+{
+	const char *found = NULL;
+	int i = 0;
+
+	for (found = str; found < str + strlen(str); ++found) {
+		for(i = 0; i < len; i++) {
+			if (strncmp(found, find[i], strlen(find[i])) == 0) {
+				return found;
+			}
+		}
+	}
+
+	return NULL;
+}
+
+/*
+ * Select and copy the previous url on screen (do nothing if there's no url).
+ *
+ * FIXME: doesn't handle urls that span multiple lines; will need to add support
+ *        for multiline "getsel()" first
+ */
+void
+copyurl(const Arg *arg) {
+	/*
+	 * () and [] can appear in urls, but excluding them here will reduce false
+	 * positives when figuring out where a given url ends.
+	 */
+	static const char URLCHARS[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
+		"abcdefghijklmnopqrstuvwxyz"
+		"0123456789-._~:/?#@!$&'*+,;=%";
+
+	static const char* URLSTRINGS[] = {"http://", "https://"};
+
+	int row = 0, /* row of current URL */
+		col = 0, /* index of current URL start */
+		colend = 0, /* column of last occurrence */
+		passes = 0; /* how many rows have been scanned */
+
+	char linestr[term.col + 1];
+	const char *c = NULL,
+		 *match = NULL;
+
+	/*
+	 * arg->i = 0 --> botton-up
+	 * arg->i = 1 --> top-down
+	 */
+	row = sel.ob.x == -1 ? term.bot : arg->i ? sel.ne.y : sel.nb.y;
+	LIMIT(row, term.top, term.bot);
+
+	colend = sel.ob.x == -1 ? term.col : arg->i ? sel.ne.x : sel.nb.x;
+	LIMIT(colend, 0, term.col);
+
+	/*
+	 * Scan from (term.row - 1,term.col - 1) to (0,0) (or in reverse,
+	 * when arg->i = 1) and find previous/next occurrance of a URL.
+	 */
+	for (passes = 0; passes < term.row; passes++) {
+		if (!arg->i) {
+			/*
+			 * Read in each column of every row until
+			 * we hit previous occurrence of URL.
+			 */
+			for (col = 0; col < colend; ++col)
+				linestr[col] = term.line[row][col].u < 128
+					? term.line[row][col].u : ' ';
+			linestr[col] = '\0';
+
+			if ((match = findlastany(linestr, URLSTRINGS,
+						sizeof(URLSTRINGS)/sizeof(URLSTRINGS[0]))))
+				break;
+
+			if (--row < 0)
+				row = term.row - 1;
+
+			colend = term.col;
+		} else {
+			/*
+			 * Read in each column of every row until
+			 * we hit next occurrence of URL.
+			 */
+			for (col = colend + 1; col < term.col; ++col)
+				linestr[col] = term.line[row][col].u < 128
+					? term.line[row][col].u : ' ';
+			linestr[col] = '\0';
+
+			if ((match = findfirstany(linestr + colend + 1, URLSTRINGS,
+						sizeof(URLSTRINGS)/sizeof(URLSTRINGS[0]))))
+				break;
+
+			if (++row >= term.row)
+				row = 0;
+
+			colend = -1;
+		}
+	}
+
+	if (match) {
+		size_t l = strspn(match, URLCHARS);
+		selstart(match - linestr, row, 0);
+		selextend(match - linestr + l - 1, row, SEL_REGULAR, 0);
+		selextend(match - linestr + l - 1, row, SEL_REGULAR, 1);
+		xsetsel(getsel());
+		xclipcopy();
+	}
+}
diff --git a/st.h b/st.h
index fd3b0d8..baa8f29 100644
--- a/st.h
+++ b/st.h
@@ -85,6 +85,7 @@ void printscreen(const Arg *);
 void printsel(const Arg *);
 void sendbreak(const Arg *);
 void toggleprinter(const Arg *);
+void copyurl(const Arg *);
 
 int tattrset(int);
 void tnew(int, int);
-- 
2.51.2