/*
 * Copyright (c) 2014 Christian Schoenebeck
 *
 * http://www.linuxsampler.org
 *
 * This file is part of LinuxSampler and released under the same terms.
 * See README file for details.
 */

#ifndef LS_INSTRUMENT_SCRIPT_VM_H
#define LS_INSTRUMENT_SCRIPT_VM_H

#include "../../common/global.h"
#include "../../scriptvm/ScriptVM.h"
#include "Event.h"
#include "../../common/Pool.h"
#include "InstrumentScriptVMFunctions.h"

namespace LinuxSampler {

    class AbstractEngineChannel;

    /** @brief Real-time instrument script VM representation.
     *
     * Holds the VM representation of all event handlers of the currently loaded
     * script, ready to be executed by the sampler engine.
     */
    struct InstrumentScript {
        VMParserContext*      parserContext; ///< VM represenation of the currently loaded script or NULL if not script was loaded. Note that it is also not NULL if parser errors occurred!
        bool                  bHasValidScript; ///< True in case there is a valid script currently loaded, false if script processing shall be skipped.
        VMEventHandler*       handlerInit; ///< VM representation of script's initilization callback or NULL if current script did not define such an init handler.
        VMEventHandler*       handlerNote; ///< VM representation of script's MIDI note on callback or NULL if current script did not define such an event handler.
        VMEventHandler*       handlerRelease; ///< VM representation of script's MIDI note off callback or NULL if current script did not define such an event handler.
        VMEventHandler*       handlerController; ///< VM representation of script's MIDI controller callback or NULL if current script did not define such an event handler.
        Pool<ScriptEvent>*    pEvents; ///< Pool of all available script execution instances. ScriptEvents available to be allocated from the Pool are currently unused / not executiong, whereas the ScriptEvents allocated on the list are currently suspended / have not finished execution yet.
        AbstractEngineChannel* pEngineChannel;

        InstrumentScript(AbstractEngineChannel* pEngineChannel) {
            parserContext = NULL;
            bHasValidScript = false;
            handlerInit = NULL;
            handlerNote = NULL;
            handlerRelease = NULL;
            handlerController = NULL;
            pEvents = NULL;
            this->pEngineChannel = pEngineChannel;
        }

        ~InstrumentScript() {
            reset();
        }

        void load(const String& text);
        void reset();
    };

    /** @brief Real-time instrument script virtual machine.
     *
     * Extends the core ScriptVM implementation with MIDI specific built-in
     * script functions and MIDI specific built-in script variables required
     * for MIDI processing by instrument script for all sampler engine
     * implementations (sampler formats) of this sampler.
     *
     * Note that this class is currently re-entrant safe, but @b not thread
     * safe! See also comments of base class ScriptVM regarding this issue.
     */
    class InstrumentScriptVM : public ScriptVM {
    public:
        InstrumentScriptVM();
        VMExecStatus_t exec(VMParserContext* parserCtx, ScriptEvent* event);
        VMFunction* functionByName(const String& name) OVERRIDE;
        std::map<String,VMIntRelPtr*> builtInIntVariables() OVERRIDE;
        std::map<String,VMInt8Array*> builtInIntArrayVariables() OVERRIDE;
        std::map<String,int> builtInConstIntVariables() OVERRIDE;
    protected:
        ScriptEvent* m_event; ///< The event currently executed by exec().

        // buil-in script variables
        VMInt8Array m_CC;
        VMInt8RelPtr m_CC_NUM;
        VMIntRelPtr  m_EVENT_ID;
        VMInt8RelPtr m_EVENT_NOTE;
        VMInt8RelPtr m_EVENT_VELOCITY;
        //VMIntArray m_KEY_DOWN; //TODO: ...
        //VMIntArray m_POLY_AT; //TODO: ...
        //int m_POLY_AT_NUM; //TODO: ...

        // buil-in script functions
        InstrumentScriptVMFunction_play_note m_fnPlayNote;
        InstrumentScriptVMFunction_set_controller m_fnSetController;
        InstrumentScriptVMFunction_ignore_event m_fnIgnoreEvent;
        InstrumentScriptVMFunction_ignore_controller m_fnIgnoreController;

        friend class InstrumentScriptVMFunction_play_note;
        friend class InstrumentScriptVMFunction_set_controller;
        friend class InstrumentScriptVMFunction_ignore_event;
        friend class InstrumentScriptVMFunction_ignore_controller;
    };

} // namespace LinuxSampler

#endif // LS_INSTRUMENT_SCRIPT_VM_H