/*
	dot_flow.c

	"emit" flow graphs to dot (graphvis).

	Copyright (C) 2012 Bill Currie <bill@taniwha.org>

	Author: Bill Currie <bill@taniwha.org>
	Date: 2012/11/01

	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 version 2
	of the License, or (at your option) any later version.

	This program 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 General Public License for more details.

	You should have received a copy of the GNU General Public License
	along with this program; if not, write to:

		Free Software Foundation, Inc.
		59 Temple Place - Suite 330
		Boston, MA  02111-1307, USA

*/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif

#ifdef HAVE_STRING_H
# include <string.h>
#endif
#ifdef HAVE_STRINGS_H
# include <strings.h>
#endif
#include <stdlib.h>

#include <QF/dstring.h>
#include <QF/quakeio.h>
#include <QF/va.h>

#include "dags.h"
#include "flow.h"
#include "function.h"
#include "expr.h"
#include "set.h"
#include "statements.h"
#include "strpool.h"

static void
print_flow_node (dstring_t *dstr, flowgraph_t *graph, flownode_t *node,
				 int level)
{
	int         indent = level * 2 + 2;
	set_iter_t *var_iter;
	flowvar_t  *var;
	int         live;

	live = node->live_vars.out && !set_is_empty (node->live_vars.out);

	if (live) {
		dasprintf (dstr, "%*ssubgraph sub_%p {\n", indent, "", node);
		//dasprintf (dstr, "%*s  rank=same;\n", indent, "");
		indent += 2;
	}
	if (node->dag) {
		print_dag (dstr, node->dag, va ("%d (%d)", node->id, node->dfn));
	} else {
		dasprintf (dstr, "%*s\"fn_%p\" [label=\"%d (%d)\"];\n", indent, "",
				   node, node->id, node->dfn);
	}
	if (live) {
		dasprintf (dstr, "%*slv_%p [shape=none,label=<\n", indent, "", node);
		dasprintf (dstr, "%*s<table border=\"0\" cellborder=\"1\" "
						 "cellspacing=\"0\">\n", indent + 2, "");
		dasprintf (dstr, "%*s<tr><td>Live Vars</td></tr>\n", indent + 4, "");
		for (var_iter = set_first (node->live_vars.out); var_iter;
			 var_iter = set_next (var_iter)) {
			var = graph->func->vars[var_iter->member];
			dasprintf (dstr, "%*s<tr><td>(%d) %s</td></tr>\n", indent + 4, "",
					   var->number, html_string(operand_string (var->op)));
		}
		dasprintf (dstr, "%*s</table>>];\n", indent + 2, "");
		if (node->dag) {
			dasprintf (dstr, "%*sdag_enter_%p -> lv_%p "
					   //"[constraint=false,style=dashed,weight=10];\n",
					   "[style=dashed,weight=10,ltail=cluster_dag_%p];\n",
					   indent, "", node->dag, node, node->dag);
		} else {
			dasprintf (dstr, "%*sfn_%p -> lv_%p "
					   //"[constraint=false,style=dashed,weight=10];\n",
					   "[style=dashed,weight=10];\n",
					   indent, "", node, node);
		}
		indent -= 2;
		dasprintf (dstr, "%*s}\n", indent, "");
	}
}

static void
print_flow_edges (dstring_t *dstr, flowgraph_t *graph, int level)
{
	int         indent = level * 2 + 2;
	int         i;
	flowedge_t *edge;
	flownode_t *t, *h;
	const char *tpref;
	const char *hpref;
	const char *style;
	const char *dir;
	int         weight;

	for (i = 0; i < graph->num_edges; i++) {
		edge = &graph->edges[i];
		t = graph->nodes[edge->tail];
		h = graph->nodes[edge->head];
		if (t->dfn >= h->dfn) {
			flownode_t *temp;
			temp = h;
			h = t;
			t = temp;

			tpref = "enter";
			hpref = "leave";
			dir = "dir=back,";
			style = "dashed";
			weight = 0;
		} else if (set_is_member (graph->dfst, i)) {
			tpref = "leave";
			hpref = "enter";
			dir = "";
			style = "bold";
			weight = 10;
		} else {
			tpref = "leave";
			hpref = "enter";
			dir = "";
			style = "solid";
			weight = 0;
		}
		dasprintf (dstr, "%*s", indent, "");
		if (t->dag)
			dasprintf (dstr, "dag_%s_%p -> ", tpref, t->dag);
		else
			dasprintf (dstr, "fn_%p -> ", t);
		if (h->dag)
			dasprintf (dstr, "dag_%s_%p [%sstyle=%s,weight=%d",
					   hpref, h->dag, dir, style, weight);
		else
			dasprintf (dstr, "fn_%p [%sstyle=%s,weight=%d",
					   h, dir, style, weight);
		if (t->dag)
			dasprintf (dstr, ",ltail=cluster_dag_%p", t->dag);
		if (h->dag)
			dasprintf (dstr, ",lhead=cluster_dag_%p", h->dag);
		dasprintf (dstr, "];\n");
	}
}

void
print_flowgraph (flowgraph_t *graph, const char *filename)
{
	int         i;
	dstring_t  *dstr = dstring_newstr();

	dasprintf (dstr, "digraph flowgraph_%p {\n", graph);
	dasprintf (dstr, "  layout=dot;\n");
	dasprintf (dstr, "  clusterrank=local;\n");
	dasprintf (dstr, "  rankdir=TB;\n");
	dasprintf (dstr, "  compound=true;\n");
	for (i = 0; i < graph->num_nodes; i++) {
		print_flow_node (dstr, graph, graph->nodes[i], 0);
	}
	print_flow_edges (dstr, graph, 0);
	dasprintf (dstr, "}\n");

	if (filename) {
		QFile      *file;

		file = Qopen (filename, "wt");
		Qwrite (file, dstr->str, dstr->size - 1);
		Qclose (file);
	} else {
		fputs (dstr->str, stdout);
	}
	dstring_delete (dstr);
}