/*-
 * Copyright (c) 2014-2018 Carsten Sonne Larsen <cs@innolan.net>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * Project homepage:
 * https://amath.innolan.net
 *
 */

#include "amathc.h"
#include "amiga_arexx.h"
#include "lib/charbuf.h"
#include "main/evaluator.h"

#if defined(AMIGA)
#include <dos/dostags.h>
#include <rexx/storage.h>
#include <rexx/rxslib.h>
#include <clib/exec_protos.h>
#include <clib/dos_protos.h>
#include <clib/rexxsyslib_protos.h>

#ifndef RXSNAME
#define RXSNAME "rexxsyslib.library"
#endif

struct RxsLib *RexxSysBase = NULL;

AmigaARexx::AmigaARexx()
{
    RexxSysBase = (struct RxsLib *)OpenLibrary((STRPTR)RXSNAME, 0);
}

AmigaARexx::~AmigaARexx()
{
    if (RexxSysBase != NULL)
    {
        CloseLibrary((struct Library *)RexxSysBase);
    }
}

void AmigaARexx::CreatePort()
{
    port = CreateMsgPort();
    if (port != NULL)
    {
        PublishPort();
    }
}

void AmigaARexx::DestroyPort()
{
    if (port != NULL)
    {
        RemPort(port);

        struct Message *msg;
        while ((msg = GetMsg(port)))
        {
            ReplyMsg(msg);
        }
        DeleteMsgPort(port);
    }
}

void AmigaARexx::PublishPort()
{
    CharBuffer *buf = new CharBuffer(12);
    bool published = false;
    int c = 0;

    do
    {
        c++;
        buf->ClearAndCopy(AREXXPORTNAME);
        buf->AppendNumber(c);
        buf->CopyTo(portName);

        Forbid();
        struct MsgPort *msgPort = FindPort((CONST_STRPTR)portName);
        if (msgPort == NULL)
        {
            port->mp_Node.ln_Pri = 0;
            port->mp_Node.ln_Name = portName;
            AddPort((struct MsgPort *)port);
            published = true;
        }
        Permit();
    } while (!published);

    delete buf;
}

static AmigaARexx *newProcess;
void AmigaARexx::ProcessEntry()
{
    newProcess->Process();
}

bool AmigaARexx::Start()
{
    Forbid();
    newProcess = this;
    process = CreateNewProcTags(
        NP_Entry, (void *)ProcessEntry,
        NP_Name, (APTR)AREXXPROCNAME,
        NP_StackSize, 64 * 1024,
        TAG_DONE);
    Permit();

    return (process != NULL);
}

void AmigaARexx::Stop()
{
    if (port == NULL)
    {
        return;
    }

    struct MsgPort *replyPort = CreateMsgPort();
    if (replyPort != NULL)
    {
        struct RexxMsg *message = (struct RexxMsg *)AllocVec(sizeof(struct RexxMsg), MEMF_ANY | MEMF_CLEAR);
        if (message != NULL)
        {
            message->rm_Node.mn_Node.ln_Type = NT_MESSAGE;
            message->rm_Node.mn_Length = sizeof(struct RexxMsg);
            message->rm_Node.mn_ReplyPort = replyPort;
            message->rm_Result1 = 99;

            Forbid();
            PutMsg(port, (struct Message *)message);
            Permit();

            WaitPort(replyPort);
            GetMsg(replyPort);
            FreeVec(message);
        }
        DeleteMsgPort(replyPort);
    }
}

void AmigaARexx::Process()
{
    CreatePort();
    if (port != NULL)
    {
        bool loop = true;

        do
        {
            WaitPort(port);

            struct RexxMsg *msg;
            while ((msg = (struct RexxMsg *)GetMsg(port)))
            {
                loop &= HandleMessage(msg);
                ReplyMsg((struct Message *)msg);
            }
        } while (loop);
    }

    DestroyPort();
}

bool AmigaARexx::HandleMessage(struct RexxMsg *message)
{
    if (message->rm_Result1 == 99)
    {
        return false;
    }

    message->rm_Result1 = 0;

    if (message->rm_Action & RXFF_RESULT)
    {
        Evaluator *evaluator = new Evaluator(message->rm_Args[0]);
        evaluator->Evaluate();
        const char *result = evaluator->GetResult();
        message->rm_Result2 = (LONG)CreateArgstring((STRPTR)result, (LONG)StrLen(result));
        delete evaluator;
    }

    return true;
}

#endif