use highest capable mouse flag (with care if 1003 is ignored in some …

…terminals)

tscreen.go

@@ -923,7 +923,7 @@ func (t *tScreen) EnableMouse(flags ...MouseFlags) {
 		flagsPresent = true
 	}
 	if !flagsPresent {
-		f = MouseMotionEvents | MouseDragEvents | MouseButtonEvents
+		f = MouseMotionEvents
 	}
 
 	t.Lock()
@@ -939,17 +939,14 @@ func (t *tScreen) enableMouse(f MouseFlags) {
 	if len(t.mouse) != 0 {
 		// start by disabling all tracking.
 		t.TPuts("\x1b[?1000l\x1b[?1002l\x1b[?1003l\x1b[?1006l")
-		if f&MouseButtonEvents != 0 {
-			t.TPuts("\x1b[?1000h")
-		}
-		if f&MouseDragEvents != 0 {
-			t.TPuts("\x1b[?1002h")
-		}
 		if f&MouseMotionEvents != 0 {
-			t.TPuts("\x1b[?1003h")
-		}
-		if f != 0 {
-			t.TPuts("\x1b[?1006h")
+			// Some terminals (putty, hterm, etc.) may ignore 1003,
+			// in which case use 1002 instead.
+			t.TPuts("\x1b[?1002h\x1b[?1003h\x1b[?1006h")
+		} else if f&MouseDragEvents != 0 {
+			t.TPuts("\x1b[?1002h\x1b[?1006h")
+		} else if f&MouseButtonEvents != 0 {
+			t.TPuts("\x1b[?1000h\x1b[?1006h")
 		}
 	}