Merge pull request #912 from andreasb242/scripting

Working on scripting / lua API

plugins/Example/main.lua

@@ -1,11 +1,19 @@
 -- This is an example Xournal++ Plugin - copy this to get started
 
-print("Hello from Lua Plugin\n");
+var_dump = require "var_dump"
 
--- Register all Toolbar actions and intialize all UI stuff  
+-- Register all Toolbar actions and intialize all UI stuff
 function initUi()
-  print("Plugin initUi called\n");
-end
+  print("Hello from Example: Plugin initUi called\n");
+
+  ref = app.registerUi({["menu"] = "Test123", ["callback"] = "exampleCallback"});
+  print("Menu reference:");
+  var_dump(ref);
 
-app.msgbox("Test123", "yes,no")
+  print("Example plugin registered\n");
+end
 
+-- Callback if the menu item is executed
+function exampleCallback()
+  app.msgbox("Test123", "yes,no");
+end

plugins/Example/var_dump.lua

@@ -0,0 +1,33 @@
+-- Source: https://gist.github.com/lunixbochs/5b0bb27861a396ab7a86#file-var_dump-lua-L1
+
+local function string(o)
+    return '"' .. tostring(o) .. '"'
+end
+
+local function recurse(o, indent)
+    if indent == nil then indent = '' end
+    local indent2 = indent .. '  '
+    if type(o) == 'table' then
+        local s = indent .. '{' .. '\n'
+        local first = true
+        for k,v in pairs(o) do
+            if first == false then s = s .. ', \n' end
+            if type(k) ~= 'number' then k = string(k) end
+            s = s .. indent2 .. '[' .. k .. '] = ' .. recurse(v, indent2)
+            first = false
+        end
+        return s .. '\n' .. indent .. '}'
+    else
+        return string(o)
+    end
+end
+
+local function var_dump(...)
+    local args = {...}
+    if #args > 1 then
+        var_dump(args)
+    else
+        print(recurse(args[1]))
+    end
+end
+return var_dump

src/plugin/Plugin.cpp

@@ -86,18 +86,26 @@ void Plugin::registerToolbar()
 		return;
 	}
 
-	// TODO Errorhandling etc.
-	// lua_register
-	// lua_atpanic
+	inInitUi = true;
 
-	if (callFunction("initUi"))
+	lua_getglobal(lua, "initUi");
+	if (lua_isfunction (lua, -1) == 1)
 	{
-		g_message("Plugin «%s» UI initialized", name.c_str());
+		if (callFunction("initUi"))
+		{
+			g_message("Plugin «%s» UI initialized", name.c_str());
+		}
+		else
+		{
+			g_warning("Plugin «%s» init failed!", name.c_str());
+		}
 	}
 	else
 	{
 		g_message("Plugin «%s» has no UI init", name.c_str());
 	}
+
+	inInitUi = false;
 }
 
 /**
@@ -110,6 +118,27 @@ string Plugin::getName()
 	return name;
 }
 
+/**
+ * @return Flag to check if init ui is currently running
+ */
+bool Plugin::isInInitUi()
+{
+	XOJ_CHECK_TYPE(Plugin);
+
+	return inInitUi;
+}
+
+/**
+ * Register a menu item
+ *
+ * @return Internal ID, can e.g. be used to disable the menu
+ */
+int Plugin::registerMenu(string menu, string callback)
+{
+	// TODO
+	return 0;
+}
+
 /**
  * Load ini file
  */
@@ -150,10 +179,43 @@ void Plugin::registerXournalppLibs(lua_State* lua)
 	for (const luaL_Reg* lib = loadedlibs; lib->func; lib++)
 	{
 		luaL_requiref(lua, lib->name, lib->func, 1);
-		lua_pop(lua, 1); /* remove lib */
+
+		// remove lib
+		lua_pop(lua, 1);
 	}
 }
 
+/**
+ * Add the plugin folder to the lua path
+ */
+void Plugin::addPluginToLuaPath()
+{
+	lua_getglobal(lua, "package");
+
+	// get field "path" from table at top of stack (-1)
+	lua_getfield(lua, -1, "path");
+
+	// For now: limit the include path to the current plugin folder, for security and compatibility reasons
+	// grab path string from top of stack
+	// string curPath = lua_tostring(lua, -1);
+	// curPath.append(";");
+	string curPath;
+	curPath.append(path);
+	curPath.append("/?.lua");
+
+	// get rid of the string on the stack we just pushed on line 5
+	lua_pop(lua, 1);
+
+	// push the new one
+	lua_pushstring(lua, curPath.c_str());
+
+	// set the field "path" in table at -2 with value at top of stack
+	lua_setfield(lua, -2, "path");
+
+	// get rid of package table from top of stack
+	lua_pop(lua, 1);
+}
+
 /**
  * Load the plugin script
  */
@@ -196,6 +258,8 @@ void Plugin::loadScript()
 
 	registerXournalppLibs(lua);
 
+	addPluginToLuaPath();
+
 	// Run the loaded Lua script
 	if (lua_pcall(lua, 0, 0, 0) != LUA_OK)
 	{
@@ -218,7 +282,10 @@ bool Plugin::callFunction(string fnc)
 	// Run the function
 	if (lua_pcall(lua, 0, 0, 0))
 	{
-		// Failed
+		const char* errMsg = lua_tostring(lua, -1);
+		XojMsgBox::showPluginMessage(name, errMsg, MSG_BT_OK, true);
+
+		g_warning("Error in Plugin: «%s», error: «%s»", name.c_str(), errMsg);
 		return false;
 	}
 

src/plugin/Plugin.h

@@ -41,6 +41,18 @@ public:
 	 */
 	string getName();
 
+	/**
+	 * @return Flag to check if init ui is currently running
+	 */
+	bool isInInitUi();
+
+	/**
+	 * Register a menu item
+	 *
+	 * @return Internal ID, can e.g. be used to disable the menu
+	 */
+	int registerMenu(string menu, string callback);
+
 private:
 	/**
 	 * Load ini file
@@ -62,6 +74,11 @@ private:
 	 */
 	void registerXournalppLibs(lua_State* lua);
 
+	/**
+	 * Add the plugin folder to the lua path
+	 */
+	void addPluginToLuaPath();
+
 public:
 	/**
 	 * Get Plugin from lua engine
@@ -101,6 +118,11 @@ private:
 	 */
 	lua_State* lua = NULL;
 
+	/**
+	 * Flag to check if init ui is currently running
+	 */
+	bool inInitUi = false;
+
 	/**
 	 * Flag if the plugin is valid / correct loaded
 	 */

src/plugin/PluginController.cpp

@@ -4,6 +4,8 @@
 #include "control/Control.h"
 #include "gui/GladeSearchpath.h"
 
+#include <StringUtils.h>
+
 #include <config-features.h>
 
 
@@ -13,7 +15,16 @@ PluginController::PluginController(Control* control)
 	XOJ_INIT_TYPE(PluginController);
 
 #ifdef ENABLE_PLUGINS
-	loadPluginsFrom(control->getGladeSearchPath()->getFirstSearchPath() + "/../plugins/");
+	string path = control->getGladeSearchPath()->getFirstSearchPath();
+	if (StringUtils::endsWith(path, "ui"))
+	{
+		path = path.substr(0, path.length() - 2) + "plugins";
+	}
+	else
+	{
+		path += "/../plugins";
+	}
+	loadPluginsFrom(path);
 #endif
 }
 

src/plugin/luapi_application.h

@@ -54,16 +54,77 @@ static int applib_msgbox(lua_State* L)
 }
 
 
+/**
+ * Allow to register menupoints or toolbar icons, this needs to be called from initUi
+ */
+static int applib_registerUi(lua_State* L)
+{
+	Plugin* plugin = Plugin::getPluginFromLua(L);
+	if (!plugin->isInInitUi())
+	{
+		luaL_error(L, "registerUi needs to be called within initUi()");
+	}
+
+	// discard any extra arguments passed in
+	lua_settop(L, 1);
+	luaL_checktype(L, 1, LUA_TTABLE);
+
+	// Now to get the data out of the table
+	// 'unpack' the table by putting the values onto
+	// the stack first. Then convert those stack values
+	// into an appropriate C type.
+	lua_getfield(L, 1, "menu");
+	lua_getfield(L, 1, "callback");
+	// stack now has following:
+	//   1  = {"menu"="MenuName", callback="functionName"}
+	//   -2 = "MenuName"
+	//   -1 = "functionName"
+
+	const char* menu = luaL_optstring(L, -2, NULL);
+	const char* callback = luaL_optstring(L, -1, NULL);
+	if (callback == NULL)
+	{
+		luaL_error(L, "Missing callback function!");
+	}
+
+	int menuId = -1;
+	int toolbarId = -1;
+
+	if (menu)
+	{
+		plugin->registerMenu(menu, callback);
+	}
+
+	// Make sure to remove all vars which are put to the stack before!
+	lua_pop(L, 2);
+
+	// Add return value to the Stack
+	lua_createtable(L, 0, 2);
+
+	lua_pushstring(L, "menuId");
+	lua_pushinteger(L, menuId);
+	lua_settable(L, -3);  /* 3rd element from the stack top */
+
+	lua_pushstring(L, "toolbarId");
+	lua_pushinteger(L, toolbarId);
+	lua_settable(L, -3);
+
+	return 1;
+}
+
+
+
 static const luaL_Reg applib[] = {
-  {"msgbox",   applib_msgbox},
+	{ "msgbox", applib_msgbox },
+	{ "registerUi", applib_registerUi },
 
-  // Placeholder
-  {"MSG_BT_OK", NULL},
-  {"MSG_BT_YES", NULL},
-  {"MSG_BT_NO", NULL},
-  {"MSG_BT_CANCEL", NULL},
+	// Placeholder
+	{"MSG_BT_OK", NULL},
+	{"MSG_BT_YES", NULL},
+	{"MSG_BT_NO", NULL},
+	{"MSG_BT_CANCEL", NULL},
 
-  {NULL, NULL}
+	{NULL, NULL}
 };
 
 /**