dwl-patches/patches/swapandfocusdir/swapandfocusdir.patch

From 285470897406b653e77d732a77356aaf9a70b799 Mon Sep 17 00:00:00 2001
From: wochap <gean.marroquin@gmail.com>
Date: Fri, 5 Jul 2024 12:37:39 -0500
Subject: [PATCH] implement swapandfocusdir

---
 config.def.h |   8 +++
 dwl.c        | 164 +++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 172 insertions(+)

diff --git a/config.def.h b/config.def.h
index 22d2171..724e15e 100644
--- a/config.def.h
+++ b/config.def.h
@@ -129,6 +129,14 @@ static const Key keys[] = {
 	{ MODKEY|WLR_MODIFIER_SHIFT, XKB_KEY_Return,     spawn,          {.v = termcmd} },
 	{ MODKEY,                    XKB_KEY_j,          focusstack,     {.i = +1} },
 	{ MODKEY,                    XKB_KEY_k,          focusstack,     {.i = -1} },
+	{ MODKEY|WLR_MODIFIER_CTRL,  XKB_KEY_Left,       focusdir,       {.ui = 0} },
+	{ MODKEY|WLR_MODIFIER_CTRL,  XKB_KEY_Right,      focusdir,       {.ui = 1} },
+	{ MODKEY|WLR_MODIFIER_CTRL,  XKB_KEY_Up,         focusdir,       {.ui = 2} },
+	{ MODKEY|WLR_MODIFIER_CTRL,  XKB_KEY_Down,       focusdir,       {.ui = 3} },
+	{ MODKEY|WLR_MODIFIER_SHIFT, XKB_KEY_Left,       swapdir,        {.ui = 0} },
+	{ MODKEY|WLR_MODIFIER_SHIFT, XKB_KEY_Right,      swapdir,        {.ui = 1} },
+	{ MODKEY|WLR_MODIFIER_SHIFT, XKB_KEY_Up,         swapdir,        {.ui = 2} },
+	{ MODKEY|WLR_MODIFIER_SHIFT, XKB_KEY_Down,       swapdir,        {.ui = 3} },
 	{ MODKEY,                    XKB_KEY_i,          incnmaster,     {.i = +1} },
 	{ MODKEY,                    XKB_KEY_d,          incnmaster,     {.i = -1} },
 	{ MODKEY,                    XKB_KEY_h,          setmfact,       {.f = -0.05f} },
diff --git a/dwl.c b/dwl.c
index dc0437e..844c1f5 100644
--- a/dwl.c
+++ b/dwl.c
@@ -241,6 +241,11 @@ typedef struct {
 	struct wl_listener destroy;
 } SessionLock;
 
+typedef struct {
+	int x;
+	int y;
+} Vector;
+
 /* function declarations */
 static void applybounds(Client *c, struct wlr_box *bbox);
 static void applyrules(Client *c);
@@ -285,6 +290,8 @@ static Monitor *dirtomon(enum wlr_direction dir);
 static void focusclient(Client *c, int lift);
 static void focusmon(const Arg *arg);
 static void focusstack(const Arg *arg);
+static void focusdir(const Arg *arg);
+static void swapdir(const Arg *arg);
 static Client *focustop(Monitor *m);
 static void fullscreennotify(struct wl_listener *listener, void *data);
 static void handlesig(int signo);
@@ -1425,6 +1432,163 @@ focusstack(const Arg *arg)
 	focusclient(c, 1);
 }
 
+Vector
+position_of_box(const struct wlr_box *box)
+{
+	return (Vector){
+		.x = box->x + box->width / 2,
+		.y = box->y + box->height / 2,
+	};
+}
+
+Vector
+diff_of_vectors(Vector *a, Vector *b)
+{
+	return (Vector){
+		.x = b->x - a->x,
+		.y = b->y - a->y,
+	};
+}
+
+const char *
+direction_of_vector(Vector *vector)
+{
+	// A zero length vector has no direction
+	if (vector->x == 0 && vector->y == 0) return "";
+
+	if (abs(vector->y) > abs(vector->x)) {
+		// Careful: We are operating in a Y-inverted coordinate system.
+		return (vector->y > 0) ? "bottom" : "top";
+	} else {
+		return (vector->x > 0) ? "right" : "left";
+	}
+}
+
+uint32_t
+vector_length(Vector *vector)
+{
+	// Euclidean distance formula
+	return (uint32_t)sqrt(vector->x * vector->x + vector->y * vector->y);
+}
+
+// Spatial direction, based on focused client position.
+Client *
+client_in_direction(const char *direction, const int *skipfloat)
+{
+	Client *cfocused = focustop(selmon);
+	Vector cfocusedposition;
+	Client *ctarget = NULL;
+	double targetdistance = INFINITY;
+	Client *c;
+
+	if (!cfocused || cfocused->isfullscreen || (skipfloat && cfocused->isfloating))
+		return NULL;
+
+	cfocusedposition = position_of_box(&cfocused->geom);
+
+	wl_list_for_each(c, &clients, link) {
+		Vector cposition;
+		Vector positiondiff;
+		uint32_t distance;
+
+		if (c == cfocused)
+			continue;
+
+		if (skipfloat && c->isfloating)
+			continue;
+
+		if (!VISIBLEON(c, selmon))
+			continue;
+
+		cposition = position_of_box(&c->geom);
+		positiondiff = diff_of_vectors(&cfocusedposition, &cposition);
+
+		if (strcmp(direction, direction_of_vector(&positiondiff)) != 0)
+			continue;
+
+		distance = vector_length(&positiondiff);
+
+		 if (distance < targetdistance) {
+			ctarget = c;
+			targetdistance = distance;
+		}
+	}
+
+	return ctarget;
+}
+
+void
+focusdir(const Arg *arg)
+{
+	Client *c = NULL;
+
+	if (arg->ui == 0)
+		c = client_in_direction("left", (int *)0);
+	if (arg->ui == 1)
+		c = client_in_direction("right", (int *)0);
+	if (arg->ui == 2)
+		c = client_in_direction("top", (int *)0);
+	if (arg->ui == 3)
+		c = client_in_direction("bottom", (int *)0);
+
+	if (c != NULL)
+		focusclient(c, 1);
+}
+
+void
+wl_list_swap(struct wl_list *list1, struct wl_list *list2)
+{
+	struct wl_list *prev1, *next1, *prev2, *next2;
+	struct wl_list temp;
+
+	if (list1 == list2) {
+		// No need to swap the same list
+		return;
+	}
+
+	// Get the lists before and after list1
+	prev1 = list1->prev;
+	next1 = list1->next;
+
+	// Get the lists before and after list2
+	prev2 = list2->prev;
+	next2 = list2->next;
+
+	// Update the next and previous pointers of adjacent lists
+	prev1->next = list2;
+	next1->prev = list2;
+	prev2->next = list1;
+	next2->prev = list1;
+
+	// Swap the next and previous pointers of the lists to actually swap them
+	temp = *list1;
+	*list1 = *list2;
+	*list2 = temp;
+}
+
+void
+swapdir(const Arg *arg)
+{
+	Client *c = NULL;
+	Client *cfocused;
+
+	if (arg->ui == 0)
+		c = client_in_direction("left", (int *)1);
+	if (arg->ui == 1)
+		c = client_in_direction("right", (int *)1);
+	if (arg->ui == 2)
+		c = client_in_direction("top", (int *)1);
+	if (arg->ui == 3)
+		c = client_in_direction("bottom", (int *)1);
+
+	if (c == NULL)
+		return;
+
+	cfocused = focustop(selmon);
+	wl_list_swap(&cfocused->link, &c->link);
+	arrange(selmon);
+}
+
 /* We probably should change the name of this, it sounds like
  * will focus the topmost client of this mon, when actually will
  * only return that client */
-- 
2.45.1