Match windows by substring in /window

This could just iterate over idNames instead, but using complete
means more recently used windows will match first.

catgirl.1

@@ -1,4 +1,4 @@
-.Dd May 28, 2021
+.Dd June 17, 2021
 .Dt CATGIRL 1
 .Os
 .
@@ -521,8 +521,9 @@ Temporarily remove a message highlight pattern.
 Temporarily remove a message ignore pattern.
 .It Ic /window
 List all windows.
-.It Ic /window Ar name
+.It Ic /window Ar name | substring
-Switch to window by name.
+Switch to window by name
+or matching substring.
 .It Ic /window Ar num | Ic / Ns Ar num
 Switch to window by number.
 .El

chat.h

@@ -360,6 +360,7 @@ char *editBuffer(size_t *pos);
 void editCompleteAdd(void);
 
 const char *complete(uint id, const char *prefix);
+const char *completeSubstr(uint id, const char *substr);
 void completeAccept(void);
 void completeReject(void);
 void completeAdd(uint id, const char *str, enum Color color);

command.c

@@ -379,7 +379,17 @@ static void commandWindow(uint id, char *params) {
 		uiShowNum(strtoul(params, NULL, 10));
 	} else {
 		id = idFind(params);
-		if (id) uiShowID(id);
+		if (id) {
+			uiShowID(id);
+			return;
+		}
+		for (const char *match; (match = completeSubstr(None, params));) {
+			id = idFind(match);
+			if (!id) continue;
+			completeAccept();
+			uiShowID(id);
+			break;
+		}
 	}
 }
 

complete.c

@@ -119,6 +119,15 @@ const char *complete(uint id, const char *prefix) {
 	return NULL;
 }
 
+const char *completeSubstr(uint id, const char *substr) {
+	for (match = (match ? match->next : head); match; match = match->next) {
+		if (match->id && match->id != id) continue;
+		if (!strcasestr(match->str, substr)) continue;
+		return match->str;
+	}
+	return NULL;
+}
+
 void completeAccept(void) {
 	if (match) prepend(detach(match));
 	match = NULL;