/**************************************************************************
 * Copyright 2014-2020 Olivier Belanger                                   *
 *                                                                        *
 * This file is part of pyo, a python module to help digital signal       *
 * processing script creation.                                            *
 *                                                                        *
 * pyo is free software: you can redistribute it and/or modify            *
 * it under the terms of the GNU Lesser General Public License as         *
 * published by the Free Software Foundation, either version 3 of the     *
 * License, or (at your option) any later version.                        *
 *                                                                        *
 * pyo is distributed in the hope that it will be useful,                 *
 * but WITHOUT ANY WARRANTY; without even the implied warranty of         *
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the          *
 * GNU Lesser General Public License for more details.                    *
 *                                                                        *
 * You should have received a copy of the GNU Lesser General Public       *
 * License along with pyo.  If not, see <http://www.gnu.org/licenses/>.   *
 *************************************************************************/
#include <stdlib.h>

#if !defined(_WIN32)
#include <dlfcn.h>
#endif

#include "Python.h"

#ifndef __m_pyo_h_
#define __m_pyo_h_

#if defined(_LANGUAGE_C_PLUS_PLUS) || defined(__cplusplus)
#define INLINE inline
extern "C" {
#else
#define INLINE
#endif

#if !defined(_WIN32)
/* libpython handle. libpython must be made available to the program loaded
** in a new interpreter. */
static void *libpython_handle;
#endif

/*
** Creates a new python interpreter and starts a pyo server in it.
** Each instance of pyo, in order to be fully independent of other
** instances, must be started in its own interpreter. An instance
** can be an object in a programming language or a plugin in a daw.
**
** arguments:
**  sr : float, host sampling rate.
**  bufsize : int, host buffer size.
**  chnls : int, number of in/out channels of the pyo server.
**
** returns the new python thread's interpreter state.
*/
INLINE PyThreadState * pyo_new_interpreter(float sr, int bufsize, int chnls) {
    char msg[64];
    PyThreadState *interp;
    if(!Py_IsInitialized()) {
        Py_InitializeEx(0);
    }

#if !defined(_WIN32)
    /* This call hardcodes 3.9 as the python version to be used to embed pyo in
       a C or C++ program. This is not a good idea and must be fixed when everthing
       is stable.
    */
    if (libpython_handle == NULL) {
#ifdef __linux__
        libpython_handle = dlopen("libpython3.9.so", RTLD_LAZY | RTLD_GLOBAL);
#elif __APPLE__
        libpython_handle = dlopen("libpython3.9.dylib", RTLD_LAZY | RTLD_GLOBAL);
#endif
    }
#endif

    PyGILState_Ensure();            /* get the GIL */

    interp = Py_NewInterpreter();   /* add a new sub-interpreter */

    /* On MacOS, trying to import wxPython in embedded python hang the process. */
    PyRun_SimpleString("import os; os.environ['PYO_GUI_WX'] = '0'");

    /* Force embedded audio server. */
    PyRun_SimpleString("os.environ['PYO_SERVER_AUDIO'] = 'embedded'");

    /* Set the default BPM (60 beat per minute). */
    PyRun_SimpleString("BPM = 60.0");

    PyRun_SimpleString("from pyo import *");
    sprintf(msg, "_s_ = Server(%f, %d, %d, 1)", sr, chnls, bufsize);
    PyRun_SimpleString(msg);
    PyRun_SimpleString("_s_.boot()\n_s_.start()\n_s_.setServer()");
    PyRun_SimpleString("_server_id_ = _s_.getServerID()");

    /* 
    ** printf %p specifier behaves differently in Linux/MacOS and Windows.
    */

#if defined(_WIN32)
    PyRun_SimpleString("_in_address_ = '0x' + _s_.getInputAddr().lower()");
    PyRun_SimpleString("_out_address_ = '0x' + _s_.getOutputAddr().lower()");
    PyRun_SimpleString("_emb_callback_ = '0x' + _s_.getEmbedICallbackAddr().lower()");
#else
    PyRun_SimpleString("_in_address_ = _s_.getInputAddr()");
    PyRun_SimpleString("_out_address_ = _s_.getOutputAddr()");
    PyRun_SimpleString("_emb_callback_ = _s_.getEmbedICallbackAddr()");
#endif

    PyEval_ReleaseThread(interp);

    return interp;
}

/*
** Returns the address, as unsigned long, of the pyo input buffer.
** Used this function if pyo's audio samples resolution is 32-bit.
**
** arguments:
**  interp : pointer, pointer to the targeted Python thread state.
**
** returns an "unsigned long" that should be recast to a float pointer.
*/
INLINE unsigned long pyo_get_input_buffer_address(PyThreadState *interp) {
    PyObject *module, *obj;
    const char *address;
    unsigned long uadd;
    PyEval_AcquireThread(interp);
    module = PyImport_AddModule("__main__");
    obj = PyObject_GetAttrString(module, "_in_address_");
    address = PyUnicode_AsUTF8(obj);
    uadd = strtoul(address, NULL, 0);
    PyEval_ReleaseThread(interp);
    return uadd;
}

/*
** Returns the address, as unsigned long long, of the pyo input buffer.
** Used this function if pyo's audio samples resolution is 64-bit.
**
** arguments:
**  interp : pointer, pointer to the targeted Python thread state.
**
** returns an "unsigned long long" that should be recast to a double pointer.
*/
INLINE unsigned long long pyo_get_input_buffer_address_64(PyThreadState *interp) {
    PyObject *module, *obj;
    const char *address;
    unsigned long long uadd;
    PyEval_AcquireThread(interp);
    module = PyImport_AddModule("__main__");
    obj = PyObject_GetAttrString(module, "_in_address_");
    address = PyUnicode_AsUTF8(obj);
    uadd = strtoull(address, NULL, 0);
    PyEval_ReleaseThread(interp);
    return uadd;
}

/*
** Returns the address, as unsigned long, of the pyo output buffer.
** Used this function if pyo's audio samples resolution is 32-bit.
**
** arguments:
**  interp : pointer, pointer to the targeted Python thread state.
**
** returns an "unsigned long" that should be recast to a float pointer.
*/
INLINE unsigned long pyo_get_output_buffer_address(PyThreadState *interp) {
    PyObject *module, *obj;
    const char *address;
    unsigned long uadd;
    PyEval_AcquireThread(interp);
    module = PyImport_AddModule("__main__");
    obj = PyObject_GetAttrString(module, "_out_address_");
    address = PyUnicode_AsUTF8(obj);
    uadd = strtoul(address, NULL, 0);
    PyEval_ReleaseThread(interp);
    return uadd;
}

/*
** Returns the address, as unsigned long long, of the pyo output buffer.
** Used this function if pyo's audio samples resolution is 64-bit.
**
** arguments:
**  interp : pointer, pointer to the targeted Python thread state.
**
** returns an "unsigned long long" that should be recast to a double pointer.
*/
INLINE unsigned long long pyo_get_output_buffer_address_64(PyThreadState *interp) {
    PyObject *module, *obj;
    const char *address;
    unsigned long long uadd;
    PyEval_AcquireThread(interp);
    module = PyImport_AddModule("__main__");
    obj = PyObject_GetAttrString(module, "_out_address_");
    address = PyUnicode_AsUTF8(obj);
    uadd = strtoull(address, NULL, 0);
    PyEval_ReleaseThread(interp);
    return uadd;
}

/*
** Returns the address, as unsigned long, of the pyo embedded callback.
** This callback must be called in the host's perform routine whenever
** pyo has to compute a new buffer of samples.
**
** arguments:
**  interp : pointer, pointer to the targeted Python thread state.
**
** returns an "unsigned long" that should be recast to a void pointer.
**
** The callback should be called with the server id (int) as argument.
**
** Prototype:
** void (*callback)(int);
*/
INLINE unsigned long pyo_get_embedded_callback_address(PyThreadState *interp) {
    PyObject *module, *obj;
    const char *address;
    unsigned long uadd;
    PyEval_AcquireThread(interp);
    module = PyImport_AddModule("__main__");
    obj = PyObject_GetAttrString(module, "_emb_callback_");
    address = PyUnicode_AsUTF8(obj);
    uadd = strtoul(address, NULL, 0);
    PyEval_ReleaseThread(interp);
    return uadd;
}

/*
** Returns the address, as unsigned long long, of the pyo embedded callback.
** This callback must be called in the host's perform routine whenever
** pyo has to compute a new buffer of samples.
**
** arguments:
**  interp : pointer, pointer to the targeted Python thread state.
**
** returns an "unsigned long long" that should be recast to a void pointer.
**
** The callback should be called with the server id (int) as argument.
**
** Prototype:
** void (*callback)(int);
*/
INLINE unsigned long long pyo_get_embedded_callback_address_64(PyThreadState *interp) {
    PyObject *module, *obj;
    const char *address;
    unsigned long long uadd;
    PyEval_AcquireThread(interp);
    module = PyImport_AddModule("__main__");
    obj = PyObject_GetAttrString(module, "_emb_callback_");
    address = PyUnicode_AsUTF8(obj);
    uadd = strtoull(address, NULL, 0);
    PyEval_ReleaseThread(interp);
    return uadd;
}

/*
** Returns the pyo server id of this thread, as an integer.
** The id must be pass as argument to the callback function.
**
** arguments:
**  interp : pointer, pointer to the targeted Python thread state.
**
** returns an integer.
*/
INLINE int pyo_get_server_id(PyThreadState *interp) {
    PyObject *module, *obj;
    int id;
    PyEval_AcquireThread(interp);
    module = PyImport_AddModule("__main__");
    obj = PyObject_GetAttrString(module, "_server_id_");
    id = PyLong_AsLong(obj);
    PyEval_ReleaseThread(interp);
    return id;
}

/*
** Closes the interpreter linked to the thread state given as argument.
**
** arguments:
**  interp : pointer, pointer to the targeted Python thread state.
*/
INLINE void pyo_end_interpreter(PyThreadState *interp) {
    /* Clean up pyo's server. */
    PyEval_AcquireThread(interp);
    PyRun_SimpleString("_s_.setServer()\n_s_.stop()\n_s_.shutdown()");
    PyEval_ReleaseThread(interp);

    PyGILState_STATE state = PyGILState_Ensure();

    /* End the sub-interpreter. */
    PyThreadState* _ts = PyThreadState_Swap(interp);
    Py_EndInterpreter(interp);
    PyThreadState_Swap(_ts);

    PyGILState_Release(state);

#if !defined(_WIN32)
    if (libpython_handle != NULL) {
        dlclose(libpython_handle);
    }
#endif

}

/*
** Shutdown and reboot the pyo server while keeping current in/out buffers.
**
** arguments:
**  interp : pointer, pointer to the targeted Python thread state.
*/
INLINE void pyo_server_reboot(PyThreadState *interp) {
    PyEval_AcquireThread(interp);
    PyRun_SimpleString("_s_.setServer()\n_s_.stop()\n_s_.shutdown()");
    PyRun_SimpleString("_s_.boot(newBuffer=False).start()");
    PyEval_ReleaseThread(interp);
}

/*
** Reboot the pyo server with new sampling rate and buffer size.
**
** arguments:
**  interp : pointer, pointer to the targeted Python thread state.
**  sr : float, host sampling rate.
**  bufsize : int, host buffer size.
*/
INLINE void pyo_set_server_params(PyThreadState *interp, float sr, int bufsize) {
    char msg[64];
    PyEval_AcquireThread(interp);
    PyRun_SimpleString("_s_.setServer()\n_s_.stop()\n_s_.shutdown()");
    sprintf(msg, "_s_.setSamplingRate(%f)", sr);
    PyRun_SimpleString(msg);
    sprintf(msg, "_s_.setBufferSize(%d)", bufsize);
    PyRun_SimpleString(msg);
    PyRun_SimpleString("_s_.boot(newBuffer=False).start()");
    PyEval_ReleaseThread(interp);
}

/*
** This function can be used to pass the DAW's bpm value to the 
** python interpreter. Changes the value of the BPM variable in
** the interpreter's global scope. (which defaults to 60).
**
** arguments:
**  interp : pointer, pointer to the targeted Python thread state.
**  bpm : double, new BPM.
*/
INLINE void pyo_set_bpm(PyThreadState *interp, double bpm) {
    char msg[64];
    PyEval_AcquireThread(interp);
    sprintf(msg, "BPM = %f", bpm);
    PyRun_SimpleString(msg);
    PyEval_ReleaseThread(interp);
}

/*
** Add a MIDI event in the pyo server processing chain. When used in 
** an embedded framework, pyo can't open MIDI ports by itself. MIDI
** inputs must be handled by the host program and sent to pyo with
** the pyo_add_midi_event function.
**
** arguments:
**  interp : pointer, pointer to the targeted Python thread state.
**  status : int, status byte.
**  data1 : int, first data byte.
**  data2 : int, second data byte.
*/
INLINE void pyo_add_midi_event(PyThreadState *interp, int status, int data1, int data2) {
    char msg[64];
    PyEval_AcquireThread(interp);
    sprintf(msg, "_s_.addMidiEvent(%d, %d, %d)", status, data1, data2);
    PyRun_SimpleString(msg);
    PyEval_ReleaseThread(interp);
}

/*
** Returns 1 if the pyo server is started for the given thread,
** Otherwise returns 0.
**
** arguments:
**  interp : pointer, pointer to the targeted Python thread state.
*/
INLINE int pyo_is_server_started(PyThreadState *interp) {
    int started;
    PyObject *module, *obj;
    PyEval_AcquireThread(interp);
    PyRun_SimpleString("started = _s_.getIsStarted()");
    module = PyImport_AddModule("__main__");
    obj = PyObject_GetAttrString(module, "started");
    started = PyLong_AsLong(obj);
    PyEval_ReleaseThread(interp);
    return started;
}

/*
** Execute a python script "file" in the given thread's interpreter (interp).
** A pre-allocated string "msg" must be given to create the python command
** used for error handling. An integer "add" is needed to indicate if the
** pyo server should be reboot or not.
**
** arguments:
**  interp : pointer, pointer to the targeted Python thread state.
**  file : char *, filename to execute as a python script. The file is first
**                 searched in the current working directory. If not found,
**                 the module will try to open it as an absolute path.
**  msg : char *, pre-allocated string used to create the python command
**                used for error handling.
**  add, int, if positive, the commands in the file will be added to whatever
**            is already running in the pyo server. If 0, the server will be
**            shutdown and reboot before executing the file.
**
** returns 0 (no error), 1 (failed to open the file) or 2 (bad code in file).
*/
INLINE int pyo_exec_file(PyThreadState *interp, const char *file, char *msg, int add) {
    int ok, isrel, badcode, err = 0;
    PyObject *module;
    PyEval_AcquireThread(interp);
    sprintf(msg, "import os\n_isrel_ = True\n_ok_ = os.path.isfile('./%s')", file);
    PyRun_SimpleString(msg);
    sprintf(msg, "if not _ok_:\n    _isrel_ = False\n    _ok_ = os.path.isfile('%s')", file);
    PyRun_SimpleString(msg);
    module = PyImport_AddModule("__main__");
    ok = PyLong_AsLong(PyObject_GetAttrString(module, "_ok_"));
    isrel = PyLong_AsLong(PyObject_GetAttrString(module, "_isrel_"));
    if (ok) {
        if (!add) {
            PyRun_SimpleString("_s_.setServer()\n_s_.stop()\n_s_.shutdown()");
            PyRun_SimpleString("_s_.boot(newBuffer=False).start()");
        }
        if (isrel) {
            sprintf(msg, "_badcode_ = False\ntry:\n    exec(open('./%s').read())\nexcept:\n    _badcode_ = True", file);
        } else {
            sprintf(msg, "_badcode_ = False\ntry:\n    exec(open('%s').read())\nexcept:\n    _badcode_ = True", file);
        }
        PyRun_SimpleString(msg);
        badcode = PyLong_AsLong(PyObject_GetAttrString(module, "_badcode_"));
        if (badcode) {
            err = 2; // err = 2 means bad code in the file.
        }
    }
    else {
        err = 1; // err = 1 means problem opening the file.
    }
    PyEval_ReleaseThread(interp);
    return err;
}

/*
** Execute a python statement "msg" in the thread's interpreter "interp".
** If "debug" is true, the statement will be executed in a try - except
** block. The error message, if any, will be write back in the *msg
** pointer and the function will return 1. If no error occured, the
** function returned 0. If debug is false, the statement is executed
** without any error checking (unsafe but faster).
**
** arguments:
**  interp : pointer, pointer to the targeted Python thread state.
**  msg : char *, pointer to a string containing the statement to execute.
**                In debug mode, if an error occured, the output log will
**                be write back in this string.
**  debug, int, if positive, the commands will be executed in a try-except
**              statement. If 0, there will be no error checking, which is
**              much faster.
**
** returns 0 (no error) or 1 (bad code in file).
*/
INLINE int pyo_exec_statement(PyThreadState *interp, char *msg, int debug) {
    int err = 0;
    if (debug) {
        PyObject *module, *obj;
        char pp[26] = "_error_=None\ntry:\n    ";
        memmove(msg + strlen(pp), msg, strlen(msg)+1);
        memmove(msg, pp, strlen(pp));
        strcat(msg, "\nexcept Exception, _e_:\n    _error_=str(_e_)");
        PyEval_AcquireThread(interp);
        PyRun_SimpleString(msg);
        module = PyImport_AddModule("__main__");
        obj = PyObject_GetAttrString(module, "_error_");
        if (obj != Py_None) {
            strcpy(msg, PyUnicode_AsUTF8(obj));
            err = 1;
        }
        PyEval_ReleaseThread(interp);
    }
    else {
        PyEval_AcquireThread(interp);
        PyRun_SimpleString(msg);
        PyEval_ReleaseThread(interp);
    }
    return err;
}

#if defined(_LANGUAGE_C_PLUS_PLUS) || defined(__cplusplus)
}
#endif

#endif /* __m_pyo_h_  */