From c282f86559f3c7858e34888c1fa0204c22ede89c Mon Sep 17 00:00:00 2001
From: elbachir-one <bachiralfa@gmail.com>
Date: Sat, 21 Sep 2024 22:59:53 +0100
Subject: [PATCH] Allowing manual switch of monocle mode.

---
 config.def.h |  7 ++---
 dwm.c        | 72 +++++++++++++++++++++++++++++++++++++++-------------
 2 files changed, 59 insertions(+), 20 deletions(-)

diff --git a/config.def.h b/config.def.h
index 9efa774..32fafc9 100644
--- a/config.def.h
+++ b/config.def.h
@@ -5,6 +5,7 @@ static const unsigned int borderpx  = 1;        /* border pixel of windows */
 static const unsigned int snap      = 32;       /* snap pixel */
 static const int showbar            = 1;        /* 0 means no bar */
 static const int topbar             = 1;        /* 0 means bottom bar */
+static const int monoclemode        = 4;        /* automatically switch to monocle mode after opening 4 windows */
 static const char *fonts[]          = { "monospace:size=10" };
 static const char dmenufont[]       = "monospace:size=10";
 static const char col_gray1[]       = "#222222";
@@ -40,8 +41,8 @@ static const int lockfullscreen = 1; /* 1 will force focus on the fullscreen win
 static const Layout layouts[] = {
 	/* symbol     arrange function */
 	{ "[]=",      tile },    /* first entry is default */
-	{ "><>",      NULL },    /* no layout function means floating behavior */
 	{ "[M]",      monocle },
+	{ "><>",      NULL },    /* no layout function means floating behavior */
 };
 
 /* key definitions */
@@ -75,8 +76,8 @@ static const Key keys[] = {
 	{ MODKEY,                       XK_Tab,    view,           {0} },
 	{ MODKEY|ShiftMask,             XK_c,      killclient,     {0} },
 	{ MODKEY,                       XK_t,      setlayout,      {.v = &layouts[0]} },
-	{ MODKEY,                       XK_f,      setlayout,      {.v = &layouts[1]} },
-	{ MODKEY,                       XK_m,      setlayout,      {.v = &layouts[2]} },
+	{ MODKEY,                       XK_m,      setlayout,      {.v = &layouts[1]} },
+	{ MODKEY,                       XK_f,      setlayout,      {.v = &layouts[2]} },
 	{ MODKEY,                       XK_space,  setlayout,      {0} },
 	{ MODKEY|ShiftMask,             XK_space,  togglefloating, {0} },
 	{ MODKEY,                       XK_0,      view,           {.ui = ~0 } },
diff --git a/dwm.c b/dwm.c
index 67c6b2b..9561896 100644
--- a/dwm.c
+++ b/dwm.c
@@ -130,6 +130,7 @@ struct Monitor {
 	Monitor *next;
 	Window barwin;
 	const Layout *lt[2];
+	int manualswitch;
 };
 
 typedef struct {
@@ -227,6 +228,7 @@ static void updatetitle(Client *c);
 static void updatewindowtype(Client *c);
 static void updatewmhints(Client *c);
 static void view(const Arg *arg);
+static int visibleclientcount(Monitor *m);
 static Client *wintoclient(Window w);
 static Monitor *wintomon(Window w);
 static int xerror(Display *dpy, XErrorEvent *ee);
@@ -382,15 +384,31 @@ applysizehints(Client *c, int *x, int *y, int *w, int *h, int interact)
 void
 arrange(Monitor *m)
 {
-	if (m)
-		showhide(m->stack);
-	else for (m = mons; m; m = m->next)
+	if (!m)
+		for (m = mons; m; m = m->next)
+			showhide(m->stack);
+	else
 		showhide(m->stack);
-	if (m) {
-		arrangemon(m);
-		restack(m);
-	} else for (m = mons; m; m = m->next)
-		arrangemon(m);
+
+	for (Monitor *mon = (m ? m : mons); mon; mon = (m ? NULL : mon->next)) {
+		unsigned int n = visibleclientcount(mon);
+
+		if (!mon->manualswitch) {
+			if (n >= monoclemode && mon->lt[mon->sellt]->arrange != monocle) {
+				setlayout(&(Arg) {.v = &layouts[1]});
+			} else if (n < monoclemode && mon->lt[mon->sellt]->arrange == monocle) {
+				setlayout(&(Arg) {.v = &layouts[0]});
+			}
+		}
+
+		if (mon->manualswitch && (n < monoclemode || n >= monoclemode)) {
+			mon->manualswitch = 0;
+		}
+
+		arrangemon(mon);
+		if (!m)
+			restack(mon);
+	}
 }
 
 void
@@ -1510,15 +1528,22 @@ setfullscreen(Client *c, int fullscreen)
 void
 setlayout(const Arg *arg)
 {
-	if (!arg || !arg->v || arg->v != selmon->lt[selmon->sellt])
-		selmon->sellt ^= 1;
-	if (arg && arg->v)
-		selmon->lt[selmon->sellt] = (Layout *)arg->v;
-	strncpy(selmon->ltsymbol, selmon->lt[selmon->sellt]->symbol, sizeof selmon->ltsymbol);
-	if (selmon->sel)
-		arrange(selmon);
-	else
-		drawbar(selmon);
+	if (!arg || !arg->v)
+		return;
+
+	Layout *newlayout = (Layout *)arg->v;
+	if (newlayout != selmon->lt[selmon->sellt]) {
+		selmon->lt[selmon->sellt] = newlayout;
+		strncpy(selmon->ltsymbol, selmon->lt[selmon->sellt]->symbol, sizeof(selmon->ltsymbol));
+		selmon->ltsymbol[sizeof(selmon->ltsymbol) - 1] = '\0';
+
+		selmon->manualswitch = 1;
+
+		if (selmon->sel)
+			arrange(selmon);
+		else
+			drawbar(selmon);
+	}
 }
 
 /* arg > 1.0 will set mfact absolutely */
@@ -2062,6 +2087,19 @@ view(const Arg *arg)
 	arrange(selmon);
 }
 
+int
+visibleclientcount(Monitor *m)
+{
+	unsigned int count = 0;
+	Client *c;
+	for (c = m->clients; c; c = c->next) {
+		if (ISVISIBLE(c)) {
+			count++;
+		}
+	}
+	return count;
+}
+
 Client *
 wintoclient(Window w)
 {
-- 
2.46.0