/*-
 * Copyright (c) 2017-2021 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.
 *
 */

#include <dos/dos.h>
#include <dos/notify.h>
#include <assert.h>

#include "config.h"
#include "mem.h"

#include "logmod.h"
#define MODULENAME "Notify"

struct NotifyRequestNode
{
    long Registered;
    struct NotifyRequest *Request;
    struct NotifyRequestNode *Next;
};

static struct NotifyRequestNode *Last = NULL;

static void AddRequest(struct NotifyRequest *request)
{
    struct NotifyRequestNode *node = AllocStructSafe(struct NotifyRequestNode);
    if (node == NULL)
    {
        return;
    }

    // Init node
    node->Registered = DOSFALSE;
    node->Request = request;
    node->Next = NULL;

    // Add to list
    Forbid();
    if (Last == NULL)
    {
        Last = node;
    }
    else
    {
        node->Next = Last;
        Last = node;
    }
    Permit();
}

void ActivateNotifyPort(struct MsgPort *port)
{
    assert(port != NULL);

    struct NotifyRequestNode *current = Last;
    while (current != NULL)
    {
        if (current->Registered != DOSTRUE)
        {
            current->Request->nr_stuff.nr_Msg.nr_Port = port;
            current->Registered = StartNotify(current->Request);

            if (current->Registered == DOSTRUE)
            {
                LogInfo("Watching for changes in %s", current->Request->nr_Name);
            }
            else
            {
                LogWarn("Could not get notifications for %s", current->Request->nr_Name);
            }
        }
        current = current->Next;
    }
}

void WatchFile(char *file, long type)
{
    struct NotifyRequest *request;

    request = AllocStructSafe(struct NotifyRequest);
    if (request == NULL)
    {
        return;
    }

    request->nr_Name = (UBYTE *)StrDupSafe(file);
    if (request->nr_Name == NULL)
    {
        return;
    }

    request->nr_Flags = NRF_SEND_MESSAGE | NRF_WAIT_REPLY;
    request->nr_UserData = type;

    AddRequest(request);
}

void CleanupNotifications(void)
{
    volatile struct NotifyRequestNode *current, *next;

    current = Last;
    while (current != NULL)
    {
        if (current->Registered == DOSTRUE)
        {
            LogTrace("Removing notification for %s", current->Request->nr_Name);
            EndNotify(current->Request);
        }
        FreeMemSafe((void *)current->Request->nr_Name);
        FreeMemSafe((void *)current->Request);

        next = current->Next;
        FreeMemSafe((void *)current);
        current = next;
    }

    Last = NULL;
}