/*
ToolsMenu - Add tools to the Workbench Tools menu

Copyright (C) 2015, 2018  Kim Fastrup Larsen

This program is free software: you can redistribute it and/or
modify it under the terms of the GNU General Public License
as published by the Free Software Foundation, either ver-
sion 3 of the License, or (at your option) any later version.

This program is distributed in the hope that it will be use-
ful, but WITHOUT ANY WARRANTY; without even the implied war-
ranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
See the GNU General Public License for more details.

You should have received a copy of the GNU General Public Li-
cense along with this program. If not, see
<http://www.gnu.org/licenses/>.

The author can be contacted on <kimflarsen@hotmail.com>
*/

#include <dos/dos.h>
#include <dos/dostags.h>
#include <exec/memory.h>
#include <workbench/startup.h>

#include <clib/dos_protos.h>
#include <clib/exec_protos.h>
#include <clib/icon_protos.h>

#ifdef USE_PRAGMAS
#include <proto/dos.h>
#include <proto/exec.h>
#include <proto/icon.h>
#endif

#include <stdlib.h>
#include <string.h>

#include "common.h"
#include "toolrun.h"

#define MIN_STACK_SIZE 4000

/* We send this extended WBStartup to any tool that we launch. It will
   contain the Workbench arguments passed to run_tool(). Once the tool quits,
   it will reply to this message, and at that point we call the clean_up
   function (also passed to run_tool()) to let it clean up the arguments. */
typedef struct {
    struct WBStartup wb_startup;
    Tr_clean_up *clean_up;
    void *user_data;
} Startmsg;

/* The tools we run will be told to reply to this port when they quit. */
static struct MsgPort *reply_port;
/* The number of tools started that haven't quit yet. */
static int running;

static void free_startmsg(Startmsg *msg)
{
    FreeVec(msg->wb_startup.sm_ToolWindow);
    FreeMem(msg, sizeof *msg);
}

/* Create the reply port and return its signal bit as a mask. */
ULONG tr_set_up()
{
    if ((reply_port = CreateMsgPort()) == NULL)
        exit(RETURN_FAIL);
    return 1UL << reply_port->mp_SigBit;
}

Bool tr_run_tool(struct WBArg *arg_list, LONG num_args,
 Tr_clean_up *clean_up, void *user_data)
{
    BPTR old_dir;
    struct DiskObject *disk_obj;
    Startmsg *startmsg;
    LONG stack_size;
    BPTR home_dir;
    struct Process *process;

    /* Load the tool's icon and check that it really is a Workbench tool. */
    old_dir = CurrentDir(arg_list[0].wa_Lock);
    if ((disk_obj = GetDiskObject(arg_list[0].wa_Name)) == NULL)
        goto run_tool_failed1;
    if (disk_obj->do_Type != WBTOOL)
        goto run_tool_failed2;
    /* Use the stacksize specified in the icon unless it's too small. */
    if ((stack_size = disk_obj->do_StackSize) < MIN_STACK_SIZE)
        stack_size = MIN_STACK_SIZE;
    /* Set up startup message. */
    if ((startmsg=AllocMem(sizeof *startmsg,MEMF_PUBLIC|MEMF_CLEAR)) == NULL)
        goto run_tool_failed2;
    startmsg->wb_startup.sm_ArgList = arg_list;
    startmsg->wb_startup.sm_NumArgs = num_args;
    startmsg->clean_up = clean_up;
    startmsg->user_data = user_data;
    /* We copy the icon's ToolWindow if it isn't NULL. */
    if (disk_obj->do_ToolWindow != NULL &&
     (startmsg->wb_startup.sm_ToolWindow = copy_of(disk_obj->do_ToolWindow))
     == NULL)
        goto run_tool_failed3;
    /* Load the tool. */
    if ((startmsg->wb_startup.sm_Segment = NewLoadSegTags(
     arg_list[0].wa_Name, TAG_DONE)) == NULL)
        goto run_tool_failed3;
    /* Get a lock for PROGDIR. */
    if ((home_dir = DupLock(arg_list[0].wa_Lock)) == 0)
        goto run_tool_failed4;
    /* Run the tool as a non-CLI process. */
    if ((process = CreateNewProcTags(
     NP_Seglist, startmsg->wb_startup.sm_Segment,
     NP_FreeSeglist, (LONG) TRUE,
     NP_Input, NULL,
     NP_CloseInput, (LONG) FALSE,
     NP_Output, NULL,
     NP_CloseOutput, (LONG) FALSE,
     NP_Error, NULL,
     NP_CloseError, (LONG) FALSE,
     NP_CurrentDir, NULL,
     NP_StackSize, stack_size,
     NP_Name, arg_list[0].wa_Name,
     NP_Priority, 0L,
     NP_ConsoleTask, NULL,
     NP_WindowPtr, NULL,
     NP_HomeDir, home_dir,
     TAG_DONE)) == NULL)
        goto run_tool_failed5;
    /* We have started the process, so we mustn't do anything after this point
       that might fail. Send the startup message to the tool. */
    startmsg->wb_startup.sm_Process = &process->pr_MsgPort;
    startmsg->wb_startup.sm_Message.mn_ReplyPort = reply_port;
    PutMsg(startmsg->wb_startup.sm_Process, (struct Message *) startmsg);
    ++running;
    FreeDiskObject(disk_obj);
    CurrentDir(old_dir);
    return YES;

run_tool_failed5:
    UnLock(home_dir);

run_tool_failed4:
    UnLoadSeg(startmsg->wb_startup.sm_Segment);

run_tool_failed3:
    free_startmsg(startmsg);

run_tool_failed2:
    FreeDiskObject(disk_obj);

run_tool_failed1:
    CurrentDir(old_dir);
    return NO;
}

/* When a tool started by tr_run_tool() quits, we receive a reply to our
   startup message. At this point we call the clean up function provided,
   then clean up the message itself. */
void tr_handle_signal()
{
    Startmsg *msg;

    while ((msg = (Startmsg *) GetMsg(reply_port)) != NULL) {
        (*msg->clean_up)(msg->wb_startup.sm_ArgList,
         msg->wb_startup.sm_NumArgs, msg->user_data);
        free_startmsg(msg);
        --running;
    }
}

/* Wait for all currently running tools to quit before cleaning up the
   reply port and returning control to the caller. */
void tr_clean_up()
{
    while (running > 0 ) {
        WaitPort(reply_port);
        tr_handle_signal();
    }
    DeleteMsgPort(reply_port);    
}