More fine-grained Activatable interfaces (#42)

* `Plugins.plug` now takes a type and property, consumer connects signals.
* Generation of a GIR file.
* Preparation for built-in extensions in `extensions` folder.
* Tweaks to `Database` to avoid exposing `Sqlite` namespace in public API.

Note: Avoiding `owned get; construct;` with `Activatable` interfaces as
used in the definition of `Peas.Activatable` because it triggers a lot
of internal compiler assertions at build time.

Fixes: #35

12 files changed, 159 insertions, 35 deletions

diff --git a/CMakeLists.txt b/CMakeLists.txt
index fb461cb9..c1ae0918 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -81,6 +81,7 @@ set(DESKTOP_ICON "${CMAKE_PROJECT_NAME}" CACHE STRING "The Icon value to be used
 
 add_subdirectory (core)
 add_subdirectory (web)
+add_subdirectory (extensions)
 enable_testing()
 add_subdirectory (tests)
 add_subdirectory (po)
diff --git a/core/CMakeLists.txt b/core/CMakeLists.txt
index d12f5fb7..ff30f54e 100644
--- a/core/CMakeLists.txt
+++ b/core/CMakeLists.txt
@@ -1,7 +1,8 @@
 # Copyright (C) 2013-2018 Christian Dywan <christian@twotoasts.de>
 
-set(LIBCORE_VERSION ${CORE_VERSION})
+set(LIBCORE_VERSION 0.6)
 set(LIBCORE_SOVERSION 0)
+set(LIBCORE_GIR Midori-${LIBCORE_VERSION})
 
 file(GLOB LIBCORE_SOURCE *.vala)
 list(REMOVE_ITEM LIBCORE_SOURCE "main.vala")
@@ -21,6 +22,8 @@ CUSTOM_VAPIS
     ${EXTRA_VAPIS}
 GENERATE_VAPI
     "${LIBCORE}"
+GENERATE_GIR
+    ${LIBCORE_GIR}
 GENERATE_HEADER
     "${LIBCORE}"
 )
@@ -33,10 +36,6 @@ OPTIONS
     ${VALAFLAGS}
 CUSTOM_VAPIS
     ${EXTRA_VAPIS}
-GENERATE_VAPI
-    "${CMAKE_PROJECT_NAME}"
-GENERATE_HEADER
-    "${CMAKE_PROJECT_NAME}"
 )
 
 add_custom_command(OUTPUT ${CMAKE_CURRENT_BINARY_DIR}/resources.c
@@ -60,6 +59,17 @@ set_target_properties("${LIBCORE}" PROPERTIES
                       VERSION ${LIBCORE_VERSION}
                       )
 
+find_program (GIR_COMPILER_BIN g-ir-compiler)
+add_custom_target("g-ir-compiler_${LIBCORE}" ALL
+                  ${GIR_COMPILER_BIN} ${CMAKE_CURRENT_BINARY_DIR}/${LIBCORE_GIR}.gir
+                  --output ${CMAKE_CURRENT_BINARY_DIR}/${LIBCORE_GIR}.typelib
+                  WORKING_DIRECTORY "${CMAKE_CURRENT_BINARY_DIR}"
+                  DEPENDS ${LIBCORE_GIR}.gir)
+install(FILES "${CMAKE_CURRENT_BINARY_DIR}/${LIBCORE_GIR}.gir"
+        DESTINATION "${CMAKE_INSTALL_DATADIR}/gir-1.0/")
+install(FILES "${CMAKE_CURRENT_BINARY_DIR}/${LIBCORE_GIR}.typelib"
+        DESTINATION "${CMAKE_INSTALL_LIBDIR}/girepository-1.0/")
+
 include_directories(
                     ${CMAKE_SOURCE_DIR}
                     ${CMAKE_CURRENT_SOURCE_DIR}
diff --git a/core/about.vala b/core/about.vala
index a0662716..bfc87260 100644
--- a/core/about.vala
+++ b/core/about.vala
@@ -11,7 +11,7 @@
 
 namespace Midori {
     [GtkTemplate (ui = "/ui/about.ui")]
-    public class About : Gtk.AboutDialog {
+    class About : Gtk.AboutDialog {
         public About (Gtk.Window parent) {
            Object (transient_for: parent,
                    website: Config.PROJECT_WEBSITE,
diff --git a/core/app.vala b/core/app.vala
index 07b06926..a495effc 100644
--- a/core/app.vala
+++ b/core/app.vala
@@ -10,6 +10,11 @@
 */
 
 namespace Midori {
+    public interface AppActivatable : Peas.ExtensionBase {
+        public abstract App app { owned get; set; }
+        public abstract void activate ();
+    }
+
     public class App : Gtk.Application {
         public File? exec_path { get; protected set; default = null; }
 
@@ -119,6 +124,10 @@ namespace Midori {
             if (!Gtk.Settings.get_default ().gtk_shell_shows_app_menu){
                 app_menu = null;
             }
+
+            var extensions = Plugins.get_default ().plug<AppActivatable> ("app", this);
+            extensions.extension_added.connect ((info, extension) => ((AppActivatable)extension).activate ());
+            extensions.foreach ((extensions, info, extension) => { extensions.extension_added (info, extension); });
         }
 
         async void internal_scheme (WebKit.URISchemeRequest request) {
diff --git a/core/browser.vala b/core/browser.vala
index f64eda2d..c22b2417 100644
--- a/core/browser.vala
+++ b/core/browser.vala
@@ -10,6 +10,11 @@
 */
 
 namespace Midori {
+    public interface BrowserActivatable : Object {
+        public abstract Browser browser { owned get; set; }
+        public abstract void activate ();
+    }
+
     [GtkTemplate (ui = "/ui/browser.ui")]
     public class Browser : Gtk.ApplicationWindow {
         public WebKit.WebContext web_context { get; construct set; }
@@ -224,7 +229,10 @@ namespace Midori {
 
             // Reveal panel toggle after panels are added
             panel.add.connect ((widget) => { panel_toggle.show (); });
-            Plugins.get_default ().plug (panel);
+
+            var extensions = Plugins.get_default ().plug<BrowserActivatable> ("browser", this);
+            extensions.extension_added.connect ((info, extension) => ((BrowserActivatable)extension).activate ());
+            extensions.foreach ((extensions, info, extension) => { extensions.extension_added (info, extension); });
         }
 
         void update_decoration_layout () {
diff --git a/core/clear-private-data.vala b/core/clear-private-data.vala
index f2f33036..edf2181b 100644
--- a/core/clear-private-data.vala
+++ b/core/clear-private-data.vala
@@ -11,7 +11,7 @@
 
 namespace Midori {
     [GtkTemplate (ui = "/ui/clear-private-data.ui")]
-    public class ClearPrivateData : Gtk.Dialog {
+    class ClearPrivateData : Gtk.Dialog {
         [GtkChild]
         Gtk.ComboBoxText timerange;
         [GtkChild]
diff --git a/core/completion.vala b/core/completion.vala
index ddb9c0a3..fe6e726a 100644
--- a/core/completion.vala
+++ b/core/completion.vala
@@ -23,6 +23,11 @@ namespace Midori {
         }
     }
 
+    public interface CompletionActivatable : Peas.ExtensionBase {
+        public abstract Completion completion { owned get; set; }
+        public abstract void activate ();
+    }
+
     public class Completion : Object, ListModel {
         List<ListModel> models = new List<ListModel> ();
         public string? key { get; set; default = null; }
@@ -38,7 +43,10 @@ namespace Midori {
             } catch (DatabaseError error) {
                 debug ("Failed to initialize completion model: %s", error.message);
             }
-            Plugins.get_default ().plug (this);
+
+            var extensions = Plugins.get_default ().plug<CompletionActivatable> ("completion", this);
+            extensions.extension_added.connect ((info, extension) => ((CompletionActivatable)extension).activate ());
+            extensions.foreach ((extensions, info, extension) => { extensions.extension_added (info, extension); });
         }
 
         public Completion () {
@@ -48,7 +56,7 @@ namespace Midori {
          * Add a model to complete from. Items need to be based on DatabaseItem
          * and filtered by key if set.
          */
-        public virtual signal void add (ListModel model) {
+        public void add (ListModel model) {
             if (model is Database) {
                 bind_property ("key", model, "key");
             }
diff --git a/core/database.vala b/core/database.vala
index f47f96a7..748f54c3 100644
--- a/core/database.vala
+++ b/core/database.vala
@@ -22,11 +22,11 @@ namespace Midori {
     public delegate bool DatabaseCallback () throws DatabaseError;
 
     public class DatabaseStatement : Object, Initable {
-        public Sqlite.Statement? stmt { get { return _stmt; } }
-        protected Sqlite.Statement _stmt = null;
+        Sqlite.Statement stmt = null;
+        int64 last_row_id = -1;
+
         public Database? database { get; set construct; }
         public string? query { get; set construct; }
-        private int64 last_row_id = -1;
 
         public DatabaseStatement (Database database, string query) throws DatabaseError {
             Object (database: database, query: query);
@@ -34,9 +34,9 @@ namespace Midori {
         }
 
         public virtual bool init (Cancellable? cancellable = null) throws DatabaseError {
-            int result = database.db.prepare_v2 (query, -1, out _stmt, null);
+            int result = database.db.prepare_v2 (query, -1, out stmt, null);
             if (result != Sqlite.OK)
-                throw new DatabaseError.COMPILE ("Failed to compile statement '%s': %s".printf (query, database.db.errmsg ()));
+                throw new DatabaseError.COMPILE ("Failed to compile statement '%s': %s".printf (query, database.errmsg));
             return true;
         }
 
@@ -84,8 +84,8 @@ namespace Midori {
         public bool step () throws DatabaseError {
             int result = stmt.step ();
             if (result != Sqlite.DONE && result != Sqlite.ROW)
-                throw new DatabaseError.EXECUTE (database.db.errmsg ());
-            last_row_id = database.db.last_insert_rowid ();
+                throw new DatabaseError.EXECUTE (database.errmsg);
+            last_row_id = database.last_row_id;
             return result == Sqlite.ROW;
         }
 
@@ -187,12 +187,12 @@ namespace Midori {
     }
 
     public class Database : Object, Initable, ListModel, Loggable {
-        public Sqlite.Database? db { get { return _db; } }
-        protected Sqlite.Database? _db = null;
-        public string? table { get; protected set; default = null; }
-        public string path { get; protected set; default = ":memory:"; }
+        internal Sqlite.Database? db = null;
         string? _key = null;
         Cancellable? populate_cancellable = null;
+
+        public string? table { get; protected set; default = null; }
+        public string path { get; protected set; default = ":memory:"; }
         public string? key { get { return _key; } set {
             _key = value;
             if (populate_cancellable != null) {
@@ -209,6 +209,16 @@ namespace Midori {
         public bool first_use { get; protected set; default = false; }
 
         /*
+         * The ID of the last inserted row.
+         */
+        public int64 last_row_id { get { return db.last_insert_rowid (); } }
+
+        /*
+         * The error message of the last failed operation.
+         */
+        public string errmsg { get { return db.errmsg (); } }
+
+        /*
          * If a filename is passed it's assumed to be in the config folder.
          * Otherwise the database is in memory only (useful for private browsing).
          */
@@ -250,9 +260,10 @@ namespace Midori {
                 flags |= Sqlite.OPEN_READWRITE;
             }
 
-            if (Sqlite.Database.open_v2 (real_path, out _db, flags) != Sqlite.OK) {
+            if (Sqlite.Database.open_v2 (real_path, out db, flags) != Sqlite.OK) {
                 throw new DatabaseError.OPEN ("Failed to open database %s".printf (real_path));
             }
+            set_data<unowned Sqlite.Database> ("db", db);
 
             if (logging) {
                 debug ("Tracing %s", path);
@@ -274,9 +285,9 @@ namespace Midori {
             int64 user_version;
             Sqlite.Statement stmt;
             if (db.prepare_v2 ("PRAGMA user_version;", -1, out stmt, null) != Sqlite.OK)
-                throw new DatabaseError.EXECUTE ("Failed to compile statement %s".printf (db.errmsg ()));
+                throw new DatabaseError.EXECUTE ("Failed to compile statement %s".printf (errmsg));
             if (stmt.step () != Sqlite.ROW)
-                throw new DatabaseError.EXECUTE ("Failed to get row %s".printf (db.errmsg ()));
+                throw new DatabaseError.EXECUTE ("Failed to get row %s".printf (errmsg));
             user_version = stmt.column_int64 (0);
 
             if (user_version == 0) {
@@ -325,7 +336,7 @@ namespace Midori {
 
         public bool exec (string query) throws DatabaseError {
             if (db.exec (query) != Sqlite.OK)
-                throw new DatabaseError.EXECUTE (db.errmsg ());
+                throw new DatabaseError.EXECUTE (errmsg);
             return true;
         }
 
diff --git a/core/plugins.vala b/core/plugins.vala
index e10de4bc..a434da31 100644
--- a/core/plugins.vala
+++ b/core/plugins.vala
@@ -22,10 +22,25 @@ namespace Midori {
 
         Plugins () {
             enable_loader ("python");
-            string source_path = Path.build_path (Path.DIR_SEPARATOR_S,
+            // Plugins installed by the user
+            string user_path = Path.build_path (Path.DIR_SEPARATOR_S,
                 Environment.get_user_data_dir (), Environment.get_prgname (), "extensions");
-            debug ("Loading plugins from %s", source_path);
-            add_search_path (source_path, null);
+            add_search_path (user_path, null);
+            debug ("Loading plugins from %s", user_path);
+
+            var exec_path = ((App)Application.get_default ()).exec_path;
+            // Try and load plugins from build folder
+            var build_path = exec_path.get_parent ().get_child ("extensions");
+            if (build_path.query_exists (null)) {
+                debug ("Loading plugins from %s", build_path.get_path ());
+                add_search_path (build_path.get_path (), user_path);
+            }
+            // System-wide plugins
+            var system_path = exec_path.get_parent ().get_parent ().get_child ("lib").get_child (Environment.get_prgname ());
+            if (system_path.query_exists (null)) {
+                debug ("Loading plugins from %s", system_path.get_path ());
+                add_search_path (system_path.get_path (), user_path);
+            }
             foreach (var plugin in get_plugin_list ()) {
                 debug ("Found plugin %s", plugin.get_name ());
                 if (!try_load_plugin (plugin)) {
@@ -37,12 +52,10 @@ namespace Midori {
         /*
          * Plug the instance of the given object to make it extensible via Peas.
          */
-        public void plug (Object object) {
-            var extensions = new Peas.ExtensionSet (this, typeof (Peas.Activatable), "object", object, null);
-            extensions.extension_added.connect ((info, extension) => { ((Peas.Activatable)extension).activate (); });
-            extensions.extension_removed.connect ((info, extension) => { ((Peas.Activatable)extension).deactivate (); });
-            extensions.foreach ((extensions, info, extension) => { extensions.extension_added (info, extension); });
+        public Peas.ExtensionSet plug<T> (string name, Object object) {
+            var extensions = new Peas.ExtensionSet (this, typeof (T), name, object, null);
             object.set_data<Object> ("midori-plug", extensions);
+            return extensions;
         }
     }
 }
diff --git a/core/tab.vala b/core/tab.vala
index f2d8bbd5..e920d864 100644
--- a/core/tab.vala
+++ b/core/tab.vala
@@ -10,6 +10,11 @@
 */
 
 namespace Midori {
+    public interface TabActivatable : Peas.ExtensionBase {
+        public abstract Tab tab { owned get; set; }
+        public abstract void activate ();
+    }
+
     [GtkTemplate (ui = "/ui/tab.ui")]
     public class Tab : WebKit.WebView {
         public string id { owned get { return "%p".printf (this); } }
@@ -57,8 +62,10 @@ namespace Midori {
             settings.enable_developer_extras = true;
 
             if (pinned) {
+                var extensions = Plugins.get_default ().plug<TabActivatable> ("tab", this);
+                extensions.extension_added.connect ((info, extension) => ((TabActivatable)extension).activate ());
+                extensions.foreach ((extensions, info, extension) => { extensions.extension_added (info, extension); });
                 load_uri (uri ?? "internal:speed-dial");
-                Plugins.get_default ().plug (this);
             } else {
                 load_uri_delayed.begin (uri, title);
             }
@@ -86,8 +93,10 @@ namespace Midori {
         public override bool focus_in_event (Gdk.EventFocus event) {
             // Delayed load on focus
             if (display_uri != uri) {
+                var extensions = Plugins.get_default ().plug<TabActivatable> ("tab", this);
+                extensions.extension_added.connect ((info, extension) => ((TabActivatable)extension).activate ());
+                extensions.foreach ((extensions, info, extension) => { extensions.extension_added (info, extension); });
                 load_uri (display_uri);
-                Plugins.get_default ().plug (this);
             }
             return true;
         }
diff --git a/extensions/CMakeLists.txt b/extensions/CMakeLists.txt
new file mode 100644
index 00000000..aec67acb
--- /dev/null
+++ b/extensions/CMakeLists.txt
@@ -0,0 +1,52 @@
+# Copyright (C) 2013-2018 Christian Dywan <christian@twotoasts.de>
+
+set(EXTENSIONDIR "${CMAKE_INSTALL_FULL_LIBDIR}/${CMAKE_PROJECT_NAME}")
+include_directories(
+                    "${CMAKE_SOURCE_DIR}"
+                    "${CMAKE_SOURCE_DIR}/core"
+                    ${DEPS_INCLUDE_DIRS}
+                    ${DEPS_GTK_INCLUDE_DIRS}
+                    ${CMAKE_BINARY_DIR}
+                    "${CMAKE_BINARY_DIR}/core"
+                    )
+file(GLOB EXTENSIONS RELATIVE ${CMAKE_CURRENT_SOURCE_DIR} *.c *.vala)
+foreach(UNIT_SRC ${EXTENSIONS})
+    if (${UNIT_SRC} MATCHES "(.vala)$")
+        string(REPLACE ".vala" "" UNIT ${UNIT_SRC})
+        include(ValaPrecompile)
+        vala_precompile(UNIT_SRC_C ${UNIT}
+            ${UNIT_SRC}
+        PACKAGES
+            ${PKGS}
+        OPTIONS
+            ${VALAFLAGS}
+        CUSTOM_VAPIS
+            ${CMAKE_BINARY_DIR}/core/${LIBCORE}.vapi
+            ${EXTRA_VAPIS}
+        )
+
+        add_library(${UNIT} MODULE ${UNIT_SRC_C})
+        set_target_properties(${UNIT} PROPERTIES
+                              COMPILE_FLAGS "${VALA_CFLAGS}"
+                              )
+    else()
+        string(REPLACE ".c" "" UNIT ${UNIT_SRC})
+        add_library(${UNIT} MODULE ${UNIT_SRC})
+        set_target_properties(${UNIT} PROPERTIES
+                              COMPILE_FLAGS ${CFLAGS}
+                              )
+    endif()
+    target_link_libraries(${UNIT}
+                          ${DEPS_LIBRARIES}
+                          ${DEPS_GTK_LIBRARIES}
+                          ${LIBCORE}
+                          )
+    install(TARGETS ${UNIT}
+            LIBRARY DESTINATION ${EXTENSIONDIR}
+            )
+    set(MANIFEST "${UNIT}.plugin")
+    configure_file(${MANIFEST}.in ${MANIFEST})
+    install(FILES ${CMAKE_CURRENT_BINARY_DIR}/${MANIFEST}
+            DESTINATION ${EXTENSIONDIR}
+            )
+endforeach ()
diff --git a/snap/snapcraft.yaml b/snap/snapcraft.yaml
index 6d390dc8..a34b715c 100644
--- a/snap/snapcraft.yaml
+++ b/snap/snapcraft.yaml
@@ -99,7 +99,10 @@ parts:
       - gstreamer1.0-libav
       - pulseaudio-module-x11
       - libmirclient9
+    organize:
+      lib/girepository-1.0/Midori-0.6.typelib: usr/lib/girepository-1.0/Midori-0.6.typelib
     stage:
+      - -usr/share/gir-1.0/Midori-0.6.gir
       - -usr/lib/*/libcups.so.2
       - -usr/share/doc/libcups2/changelog.Debian.gz
       - -usr/lib/*/libsoup-2.4.so.1.7.0