axmol/extensions/scripting/lua-bindings/manual/platform/android/CCLuaJavaBridge.h

/****************************************************************************
 Copyright (c) 2017-2018 Xiamen Yaji Software Co., Ltd.

 https://axis-project.github.io/

 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal
 in the Software without restriction, including without limitation the rights
 to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 copies of the Software, and to permit persons to whom the Software is
 furnished to do so, subject to the following conditions:

 The above copyright notice and this permission notice shall be included in
 all copies or substantial portions of the Software.

 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 THE SOFTWARE.
 ****************************************************************************/

#ifndef COCOS2DX_SCRIPT_LUA_COCOS2DX_SUPPORT_PLATFORM_ANDROID_LUA_JAVA_BRIDGE_H
#define COCOS2DX_SCRIPT_LUA_COCOS2DX_SUPPORT_PLATFORM_ANDROID_LUA_JAVA_BRIDGE_H
#if defined(__ANDROID__)

#    include <jni.h>
#    include <string.h>
#    include <string>
#    include <vector>

using namespace std;

extern "C" {
#    include "lua.h"
}

#    define LUAJ_ERR_OK 0
#    define LUAJ_ERR_TYPE_NOT_SUPPORT (-1)
#    define LUAJ_ERR_INVALID_SIGNATURES (-2)
#    define LUAJ_ERR_METHOD_NOT_FOUND (-3)
#    define LUAJ_ERR_EXCEPTION_OCCURRED (-4)
#    define LUAJ_ERR_VM_THREAD_DETACHED (-5)
#    define LUAJ_ERR_VM_FAILURE (-6)

#    define LUAJ_REGISTRY_FUNCTION "luaj_function_id"       // table[function] = id
#    define LUAJ_REGISTRY_RETAIN "luaj_function_id_retain"  // table[id] = retain count

/**
 * @addtogroup lua
 * @{
 */

/**
 * Build a bridge between Java and Lua script.
 * This mechanism make Lua and Java call each other easily.
 */
class LuaJavaBridge
{
public:
    ///@cond
    /**
     * Bind callStaticMethod of LuaJavaBridge to Lua.
     * In current mechanism, we could call LuaJavaBridge.callStaticMethod(className, methodName, args) in Lua directly.
     * Meanwhile the callStaticMethod of LuaObjcBridge binding function is wrapped in the luaj.lua
     */
    static void luaopen_luaj(lua_State* L);
    ///@endcond

    /**
     * Add a reference count for the Lua functionId,and save this reference in the Lua table named
     * luaj_function_id_retain.
     *
     * @param functionId the id of Lua function.
     * @return the reference count of the functionId if luaj_function_id_retain table exists and the corresponding value
     * for functionId exists, otherwise return 0.
     *
     * @lua NA
     * @js NA
     */
    static int retainLuaFunctionById(int functionId);

    /**
     * Release a reference count for the Lua functionId, If the reference count is still greater than 0,save this
     * reference in the Lua table named luaj_function_id_retain. Otherwise, remove the reference about this functionId
     * in the luaj_function_id table and the luaj_function_id_retain table by set the corresponding value nil.
     *
     * @param functionId the id of Lua function.
     * @return the reference count of the functionId if the luaj_function_id table, the luaj_function_id_retain table
     * and the corresponding value for functionId exists a reference count for the Lua functionId is still greater than
     * 0, and otherwise return 0.
     *
     * @lua NA
     * @js NA
     */
    static int releaseLuaFunctionById(int functionId);

    /**
     * Call the Lua function corresponding to the functionId with the string pointer arg.
     *
     * @param functionId the values corresponding to the Lua function.
     * @param arg the string pointer point to the argument.
     * @return a number value returned from the Lua function when call successfully, otherwise return -1 or the opposite
     * number for one of the three numbers LUA_ERRRUN, LUA_ERRMEM and LUA_ERRERR.
     *
     * @lua NA
     * @js NA
     */
    static int callLuaFunctionById(int functionId, const char* arg);

    /**
     * Call a global Lua function named functionName with the string pointer arg.
     *
     * @param functionName the name of global function.
     * @param arg the string pointer point to the argument.
     * @return a number value returned from the Lua function when call successfully, otherwise return -1 or the opposite
     * number for one of the three numbers LUA_ERRRUN, LUA_ERRMEM and LUA_ERRERR.
     *
     * @lua NA
     * @js NA
     */
    static int callLuaGlobalFunction(const char* functionName, const char* arg);

private:
    typedef enum
    {
        TypeInvalid  = -1,
        TypeVoid     = 0,
        TypeInteger  = 1,
        TypeFloat    = 2,
        TypeBoolean  = 3,
        TypeString   = 4,
        TypeVector   = 5,
        TypeFunction = 6,
    } ValueType;

    typedef vector<ValueType> ValueTypes;

    typedef union
    {
        int intValue;
        float floatValue;
        int boolValue;
        string* stringValue;
    } ReturnValue;

    class CallInfo
    {
    public:
        CallInfo(const char* className, const char* methodName, const char* methodSig)
            : m_valid(false)
            , m_error(LUAJ_ERR_OK)
            , m_className(className)
            , m_methodName(methodName)
            , m_methodSig(methodSig)
            , m_returnType(TypeVoid)
            , m_argumentsCount(0)
            , m_retjs(NULL)
            , m_env(NULL)
            , m_classID(NULL)
            , m_methodID(NULL)
        {
            memset(&m_ret, 0, sizeof(m_ret));
            m_valid = validateMethodSig() && getMethodInfo();
        }
        ~CallInfo();

        bool isValid() { return m_valid; }

        int getErrorCode() { return m_error; }

        JNIEnv* getEnv() { return m_env; }

        int argumentTypeAtIndex(size_t index) { return m_argumentsType.at(index); }

        bool execute();
        bool executeWithArgs(jvalue* args);
        int pushReturnValue(lua_State* L);

    private:
        bool m_valid;
        int m_error;

        string m_className;
        string m_methodName;
        string m_methodSig;
        int m_argumentsCount;
        ValueTypes m_argumentsType;
        ValueType m_returnType;

        ReturnValue m_ret;
        jstring m_retjs;

        JNIEnv* m_env;
        jclass m_classID;
        jmethodID m_methodID;

        bool validateMethodSig();
        bool getMethodInfo();
        ValueType checkType(const string& sig, size_t* pos);
    };

    static int callJavaStaticMethod(lua_State* L);
    static int retainLuaFunction(lua_State* L, int functionIndex, int* retainCountReturn);
    static int getMethodInfo(CallInfo* call, const char* className, const char* methodName, const char* paramCode);
    static int fetchArrayElements(lua_State* L, int index);
    static int callAndPushReturnValue(lua_State* L, CallInfo* call, jvalue* args);

    static lua_State* s_luaState;
    static int s_newFunctionId;
};

#endif

// end group
/// @}
#endif  // COCOS2DX_SCRIPT_LUA_COCOS2DX_SUPPORT_PLATFORM_ANDROID_LUA_JAVA_BRIDGE_H