/*
 * CIF support code for Tock programs
 * Copyright (C) 2008  University of Kent
 *
 * This library 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 2 of the License, or (at
 * your option) any later version.
 *
 * This library 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 this library.  If not, see <http://www.gnu.org/licenses/>.
 */

#ifndef TOCK_SUPPORT_CIF_H
#define TOCK_SUPPORT_CIF_H

#include <cif.h>
#include <glib.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/ioctl.h>
#include <termios.h>
#include <unistd.h>

//{{{  occam_stop
#define occam_stop(pos, nargs, format, args...) \
	do { \
		ExternalCallN (fprintf, 3 + nargs, stderr, \
		               "Program stopped at %s: " format "\n", \
		               pos, ##args); \
		SetErr (); \
	} while (0)
//}}}

#define occam_extra_param Workspace wptr,

#include <tock_support.h>

//{{{ Process starting and stopping

// This is a version of the CCSP function that uses malloc.  We should replace this eventually, preferably using LightProcAlloc.
static inline Workspace TockProcAlloc (Workspace wptr, word args, word stack)
{
    Workspace ws;
    word words = WORKSPACE_SIZE (args, stack);

    ws = malloc(words*sizeof(word));

    ws += CIF_PROCESS_WORDS;
    ws[BarrierPtr] = (word) NULL;
    ws[StackPtr] = words - CIF_PROCESS_WORDS;

    return ws;
}

//The corresponding version that frees the workspace
static inline void TockProcFree(Workspace wptr, Workspace ws)
{
	ws -= CIF_PROCESS_WORDS;
	free(ws);
}
//}}}

//{{{ channel array initialisation
static inline void tock_init_chan_array (Channel *, Channel **, int) occam_unused;
static inline void tock_init_chan_array (Channel *pointTo, Channel **pointFrom, int count) {
	for (int i = 0; i < count; i++) {
		pointFrom[i] = &(pointTo[i]);
	}
}
//}}}

//{{{ mobile intrinsics
static inline void occam_RESIZE_MOBILE_ARRAY_1D (Workspace wptr, const int element_size, mt_array_t ** pptr, const int count) occam_unused;
static inline void occam_RESIZE_MOBILE_ARRAY_1D (Workspace wptr, const int element_size, mt_array_t ** pptr, const int count) {
	*pptr = MTResize1D (wptr, *pptr, count*element_size);
	(*pptr)->dimensions[0] = count;
}

//}}}

//{{{ other mobile stuff
static inline void* TockMTLock(Workspace wptr, void* ptr, int lock) occam_unused;
static inline void* TockMTLock(Workspace wptr, void* ptr, int lock) {
	MTLock(wptr, ptr, lock);
	return ptr;
}

static inline mt_array_t* TockZeroMobileArray(mt_array_t* arr, int elem_size, int num_dims) occam_unused;
static inline mt_array_t* TockZeroMobileArray(mt_array_t* arr, int elem_size, int num_dims) {
  int total_size = elem_size;
  for (int i = 0; i < num_dims; i++) {
    total_size *= arr->dimensions[i];
  }
  memset(arr->data, 0, total_size);
  return arr;
}
//}}}

//{{{  top-level process interface
static void tock_tlp_input_bcall (FILE *in, int *ch) occam_unused;
static void tock_tlp_input_bcall (FILE *in, int *ch) {
	*ch = fgetc (in);
}

static void tock_tlp_input (Workspace wptr) occam_unused;
static void tock_tlp_input (Workspace wptr) {
	Channel *out	= ProcGetParam (wptr, 0, Channel *);
	Channel *kill	= ProcGetParam (wptr, 1, Channel *);
	FILE *in	= ProcGetParam (wptr, 2, FILE *);

	while (true) {
		int ch = -1;
		KillableBlockingCallN (wptr, tock_tlp_input_bcall, kill, 2, in, &ch);
		if (ch == -1) {
			// The call was killed -- exit.
			break;
		}

		ChanOutChar (wptr, out, ch);
	}
}

static void tock_tlp_input_kill (Workspace wptr, Channel *kill) occam_unused;
static void tock_tlp_input_kill (Workspace wptr, Channel *kill) {
	while (true) {
		// If KillBlockingCall returns -1, the call hasn't started yet,
		// so we reschedule and try again. (If tock_tlp_input is
		// blocked on output we should deadlock anyway.)
		if (KillBlockingCall (wptr, kill) != -1)
			break;
		Reschedule (wptr);
	}
}

static void tock_tlp_output (Workspace wptr) occam_unused;
static void tock_tlp_output (Workspace wptr) {
	Channel *in	= ProcGetParam (wptr, 0, Channel *);
	Channel *kill	= ProcGetParam (wptr, 1, Channel *);
	FILE *out	= ProcGetParam (wptr, 2, FILE *);

	while (true) {
		switch (ProcAlt (wptr, in, kill, NULL)) {
			case 0: {
				uint8_t ch;
				ChanIn (wptr, in, &ch, sizeof ch);
				if (ch == 255) { // FLUSH
					fflush (out);
				} else {
					ExternalCallN (fputc, 2, ch, out);
				}

				break;
			}
			case 1: {
				bool b;
				ChanIn (wptr, kill, &b, sizeof b);
				fflush (out);

				return;
			}
		}
	}
}

static void tock_tlp_output_kill (Workspace wptr, Channel *kill) occam_unused;
static void tock_tlp_output_kill (Workspace wptr, Channel *kill) {
	bool b = true;

	ChanOut (wptr, kill, &b, sizeof b);
}
//}}}

//{{{  CCSP startup and terminal handling
static void tock_exit_handler (int status, word core) occam_unused;
static void tock_exit_handler (int status, word core) {
	tock_restore_terminal ();
	ccsp_default_exit_handler (status, core);
}

static void tock_init_ccsp (bool uses_stdin) occam_unused;
static void tock_init_ccsp (bool uses_stdin) {
	ccsp_set_branding ("Tock");

	tock_configure_terminal (uses_stdin);

	if (!ccsp_init ())
		exit (1);

	ccsp_set_exit_handler (tock_exit_handler);
}
//}}}

//{{{ Helpers for lists

//Just like g_queue_push_tail, but returns the queue pointer:
static inline GQueue* tock_push_tail(GQueue*, gpointer) occam_unused;
static inline GQueue* tock_push_tail(GQueue* queue, gpointer data)
{
	g_queue_push_tail(queue,data);
	return queue;
}

static void tock_free_helper(gpointer, gpointer) occam_unused;
static void tock_free_helper(gpointer data, gpointer _unused)
{
	free(data);
}

//This should go away once we start using mobiles properly:
static gpointer tock_new_helper(gpointer, guint) occam_unused;
static gpointer tock_new_helper(gpointer src, guint sz)
{
	gpointer ret = malloc(sz);
	memcpy(ret,src,sz);
	return ret;
}

//Deletes everything in the queue and frees it:
static inline void tock_free_queue(GQueue*) occam_unused;
static inline void tock_free_queue(GQueue* queue)
{
	g_queue_foreach(queue, tock_free_helper, NULL);
	g_queue_free(queue);
}

//Moves both queues into a concatenated new queue.
//Don't rely on either of the passed arguments being
//valid afterwards
static inline GQueue* tock_queue_concat(GQueue*,GQueue*) occam_unused;
static inline GQueue* tock_queue_concat(GQueue* a, GQueue* b)
{
	a->length += b->length;
	a->head = g_list_concat(a->head, b-> head);
	a->tail = b->tail;
	b->head = NULL;
	b->tail = NULL;
	b->length = 0;
	g_queue_free(b);
	return a;
}

//}}}

#endif