djview: choose Qt version to use based on macOS version

Author: szhorvat

aqua/djview/Portfile

@@ -32,24 +32,36 @@ depends_lib-append  port:djvulibre
 universal_variant   yes
 use_autoreconf      yes
 
-if {$subport eq $name} {
+if {${os.major} < 17} {
     PortGroup           qt4 1.0
-    conflicts           djview-qt5
-} else {
+
+} elseif {${os.major} < 21} {
     PortGroup           qt5 1.0
-    conflicts           ${name}
+
+    # Location of qmake
+    configure.env-append QMAKE=${prefix}/libexec/qt6/bin/qmake \
+                         QMAKESPEC=macx-clang
+} else {
+    PortGroup           qt6 1.0
+
+    qt6.depends_lib     qt5compat
+
+    # Location of qmake
+    configure.env-append QMAKE=${prefix}/libexec/qt6/bin/qmake \
+                         QMAKESPEC=macx-clang
 }
 
 subport djview-qt5 {
-    #Location of qmake
-    configure.env-append QMAKE=${prefix}/libexec/qt5/bin/qmake \
-                         QMAKESPEC=macx-clang
+    PortGroup           obsolete 1.0
+
+    replaced_by         djview
 }
 
 configure.ldflags
 configure.args \
     --disable-nsdejavu \
-    --disable-desktopfiles
+    --disable-desktopfiles \
+    --enable-mac
 
 build.args-append   V=1