Add flatpak metadata and improve meson system

data/meson.build

@@ -2,6 +2,7 @@ desktop_conf = configuration_data()
 desktop_conf.set('NAME', meson.project_name())
 desktop_conf.set('ICON', application_id)
 desktop_conf.set('APP_ID', application_id)
+desktop_conf.set('BASE_ID', base_id)
 desktop_conf.set('EXEC', meson.project_name())
 
 # Desktop file
@@ -10,19 +11,24 @@ configure_file(
   output: '@BASENAME@',
   install: true,
   configuration: desktop_conf,
-  install_dir: applicationsdir
+  install_dir: metainfodir
 )
 
-# Scalable icon
-install_data(
-  '@0@.svg'.format(base_id),
-  install_dir: iconsdir / 'hicolor' / 'scalable' / 'apps',
-  rename: '@0@.svg'.format(application_id)
+# Metainfo file
+configure_file(
+  input: '@0@.metainfo.xml.in'.format(base_id),
+  output: '@BASENAME@',
+  install: true,
+  configuration: desktop_conf,
+  install_dir: metainfodir
 )
 
-# Symbolic icon
-install_data(
-  '@0@-symbolic.svg'.format(base_id),
-  install_dir: iconsdir / 'hicolor' / 'symbolic' / 'apps',
-  rename: '@0@-symbolic.svg'.format(application_id)
+configure_file(
+  input: '@0@.gschema.xml.in'.format(base_id),
+  output: '@0@.gschema.xml'.format(application_id),
+  configuration: desktop_conf,
+  install: true,
+  install_dir: datadir / 'glib-2.0' / 'schemas'
 )
+
+subdir('icons')